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Last Updated :2024/10/27

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Master

Affiliation (Master)

  • Faculty of Veterinary Medicine　Veterinary Medicine　Preventive Veterinary Medicine

Affiliation (Master)

  • Faculty of Veterinary Medicine　Veterinary Medicine　Preventive Veterinary Medicine

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Degree

  • Ph.D（Hokkaido University）

Profile and Settings

  • Name (Japanese)

    Kariwa

  • Name (Kana)

    Hiroaki

  • Name

    200901056681540702

Alternate Names

Achievement

Research Interests

  • 人獣共通感染症   ウイルス学   公衆衛生学   Zoonosis   Virology   Public Health   

Research Areas

  • Life sciences / Veterinary medicine

Awards

  • 2007/04 The Japanese Society of Veterinary Science The Award of the Japanese Society of Veterinary Science
     Comparative epidemiological study of hantavirus infection among wild rodents 
    受賞者: KARIWA Hiroaki

Published Papers

  • Duong Thi Ngoc Thuy, Michihito Sasaki, Yasuko Orba, Passawat Thammahakin, Keisuke Maezono, Shintaro Kobayashi, Hiroaki Kariwa
    Virology 597 110168 - 110168 2024/07/03 
    Viruses in the genus Orthohantavirus within the family Hantaviridae cause human hantavirus infections and represent a threat to public health. Hokkaido virus (HOKV), a genotype of Orthohantavirus puumalaense (Puumala virus; PUUV), was first identified in Tobetsu, Hokkaido, Japan. Although it is genetically related to the prototype of PUUV, the evolutionary pathway of HOKV is unclear. We conducted a field survey in a forest in Tobetsu in 2022 and captured 44 rodents. Complete coding genome sequences of HOKVs were obtained from five viral-RNA-positive rodents (four Myodes rufocanus bedfordiae and one Apodemus speciosus). Phylogenetic analysis revealed a close relationship between the phylogenies and geographical origins of M. rufocanus-related orthohantaviruses. Comparison of the phylogenetic trees of the S segments of orthohantaviruses and the cytochrome b genes of Myodes species suggested that Myodes-related orthohantaviruses evolved in Myodes rodent species as a result of genetic isolation and host switching.
  • Shintaro Kobayashi, Seira Kawai, Yukine Fukuda, Haruto Eguchi, Keisuke Maezono, Passawat Thammahakin, Hirofumi Sawa, Hiroaki Kariwa
    iScience 27 (4) 109539 - 109539 2024/04/19 
    Rab27a, a Rab family small GTPases, plays an important role in the trafficking and secretion of the intracellular proteins and has been reported to promote various viral multiplication. However, whether Rab27a is involved in West Nile virus (WNV) multiplication is unknown. This study examined the ability of Rab27a to suppress WNV multiplication. The inhibition of Rab27a expression increased viral multiplication and the intracellular levels of WNV structural proteins, E and prM proteins. Rab27a partially colocalized with E protein, mainly in the perinuclear region, while inhibition of Rab27a expression resulted in diffuse subcellular localization of E protein. In addition, some of the perinuclear E protein colocalized with the lysosomal marker LAMP1, and inhibition of lysosomal acidification increased intracellular levels of Rab27a and E proteins. These observations suggested that Rab27a inhibits WNV multiplication by inducing the degradation of viral protein in lysosomes.
  • Shintaro Kobayashi, Ryoko Kawakami, Chisaki Takeda, Keisuke Maezono, Passawat Thammahakin, Haruto Eguchi, Bernard M Hang'ombe, Yasuko Orba, Hirofumi Sawa, Kentaro Yoshii, Hiroaki Kariwa
    Virology 588 109902 - 109902 2023/11 
    West Nile virus (WNV) causes encephalitis in human and animals. WNV is phylogenetically classified into at least five distinct genetic lineages with different pathogenicity. The pathogenesis of West Nile encephalitis is affected by ubiquitin accumulation in infected cells, but the mechanism is unknown. In this study, the association between ubiquitin accumulation and WNV pathogenicity was investigated. Ubiquitin accumulation was detected in cells infected with NY99 strain belonging to lineage-1, but not FCG and Zmq16 strains belonging to lineage-2. Substitution of the Finger and Palm sub-domains of NS5 from lineage-1 to -2 decreased ubiquitin accumulation and viral replication. Furthermore, the survival rate was increased, and viral replication and ubiquitin accumulation in the brain were attenuated, in mice inoculated with the substituted WNV compared with lineage-1 WNV. Therefore, the intracellular ubiquitin accumulation induced by the Finger and Palm sub-domains of NS5 is linked to the differences in pathogenicity among WNV lineages.
  • ウエストナイルウイルスの脳内侵入機構解明のための脳組織の病理組織学的解析
    梶山 実紗, 福田 幸音, 佐々木 道仁, Passawat Thammahkin, 前園 佳祐, 長谷部 理絵, 村上 正晃, 苅和 宏明, 小林 進太郎
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 166回 150 - 150 1347-8621 2023/09
  • ダニ媒介脳炎における検査法の評価および後方視的調査結果について
    山口 宏樹, 駒込 理佳, 三好 正浩, 伊東 拓也, 後藤 明子, 三津橋 和也, 渡 慧, 山野 公明, 小林 進太郎, 苅和 宏明, 好井 健太朗
    病原微生物検出情報月報 国立感染症研究所 44 (8) 128 - 130 0915-5813 2023/08 
    2017年6月～2023年3月までのダニ媒介脳炎の検査結果を示し、その検査法の有用性について検討した。さらに、2017年6月以前のダニ媒介感染症疑い症例における後方視的調査結果を報告した。当所に搬入された294症例369検体についてELISAおよび中和試験を実施した。その結果、新たに3症例(6検体)からダニ媒介脳炎ウイルス(TBEV)に対する特異的抗体が検出された。ELISAと中和試験の結果を比較した結果、IgM捕捉ELISAにおいて陽性の6検体では偽陰性・偽陽性はみられず、IgG-ELISAで陰性、中和試験において抗体が検出された3検体はそれぞれの回復期血清においてIgG抗体陽転が確認された。2017年6月以前に当所に搬入された88症例99検体において後方視的調査を実施した。その結果、3症例(3検体)からIgM抗体および中和抗体が検出され、新たに2名のTBEV抗体陽性症例の存在が明らかとなった。
  • Passawat Thammahakin, Keisuke Maezono, Naoya Maekawa, Hiroaki Kariwa, Shintaro Kobayashi
    Journal of neurovirology 29 (4) 367 - 375 2023/08 
    West Nile virus (WNV) has emerged as a significant cause of viral encephalitis in humans and horses. However, the pathogenesis of the West Nile encephalitis remains unclear. Microglia are activated by WNV infection, and the pathogenic involvement of their phenotypes is controversial. In this study, we examined the diversity of microglia phenotypes caused by WNV infection by assessing various microglia markers and identified disease-associated microglia in WNV-infected mouse brain tissue. Cells positive for general microglia markers such as Iba1, P2RY12, or TMEM119 were detected in the control and WNV-infected brain tissue. The morphology of the positive cells in brain tissue infected by WNV was different from that of control brain tissue, indicating that WNV infection induced activation of microglia. The activated microglia were classified into various phenotypes by investigation of specific marker expression. Among the activated microglia, disease-associated microglia that were positive for CD11c and weakly positive for TMEM119 were detected close to the WNV-infected cells. These results indicate that WNV infection induces activation of diverse microglia phenotypes and that disease-associated microglia may be associated with the pathogenicity of WNV infection in the mouse brain.
  • Shintaro Kobayashi, Yukine Fukuda, Kentaro Yoshii, Passawat Thammahakin, Keisuke Maezono, Luděk Eyer, Daniel Růžek, Hiroaki Kariwa
    Journal of virological methods 317 114744 - 114744 2023/07 
    West Nile virus (WNV) is transmitted to humans and animals by a mosquito and enters the central nervous system, leading to lethal encephalitis. Reporter viruses expressing fluorescent proteins enable detection of infected cells in vitro and in vivo, facilitating evaluation of the dynamics of viral infection, and the development of diagnostic or therapeutic methods. In this study, we developed a method for production of a recombinant replication-competent WNV expressing mCherry fluorescent protein. The expression of mCherry was observed in viral antigen-positive cells in vitro and in vivo, but the growth of the reporter WNV was reduced as compared to the parental WNV. The expression of mCherry was stable during 5 passages in reporter WNV-infected culture cells. Neurological symptoms were observed in mice inoculated intracranially with the reporter WNV. The reporter WNV expressing mCherry will facilitate research into WNV replication in mouse brains.
  • Dai Tsujino, Kentaro Yoshii, Misa Kajiyama, Yuji Takahashi, Naoya Maekawa, Hiroaki Kariwa, Shintaro Kobayashi
    Virus research 321 198914 - 198914 2022/09/03 [Refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) is a zoonotic virus that causes tick-borne encephalitis (TBE) in humans. Infections of Sapporo-17-Io1 (Sapporo) and Oshima 5-10 (Oshima) TBEV strains showed different pathogenic effects in mice. However, the differences between the two strains are unknown. In this study, we examined neuronal degeneration and death, and activation of glial cells in mice inoculated with each strain to investigate the pathogenesis of TBE. Viral growth was similar between Sapporo and Oshima, but neuronal degeneration and death, and activation of glial cells, was more prominent with Oshima. In human neuroblastoma cells, apoptosis and pyroptosis were not observed after TBEV infection. However, the expression of the necroptosis marker, mixed lineage kinase domain-like (MLKL) protein, was upregulated by TBEV infection, and this upregulation was more pronounced in Oshima than Sapporo infections. As necroptosis is a pro-inflammatory type of cell death, differences in necroptosis induction might be involved in the differences in neuropathogenicity of TBE.
  • ダニ媒介性脳炎の治療法開発に向けた血液脳関門透過性分子の研究
    福田 美津紀, 深野 紗代, 小林 進太郎, 前川 直也, 高橋 侑嗣, 平野 港, 苅和 宏明, 今内 覚, 好井 健太朗
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 165回 [F1P - 12] 1347-8621 2022/09
  • ダニ媒介性脳炎の治療法開発に向けた血液脳関門透過性分子の研究
    福田 美津紀, 深野 紗代, 小林 進太郎, 前川 直也, 高橋 侑嗣, 平野 港, 苅和 宏明, 今内 覚, 好井 健太朗
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 165回 [F1P - 12] 1347-8621 2022/09
  • Kazuma Tamiya, Shintaro Kobayashi, Kentaro Yoshii, Hiroaki Kariwa
    Virus research 318 198830 - 198830 2022/05/28 [Refereed][Not invited]
     
    Hantaviruses are potentially fatal zoonotic pathogens of the family Hantaviridae. No human infection by the Hokkaido genotype of Puumala orthohantavirus (PUUV-Hok) has been reported. However, other PUUV genotypes cause hemorrhagic fever with renal syndrome (HFRS) in humans. Autophagy is a highly conserved lysosomal degradation process in eukaryotic cells that affects the replication of various viruses. In this study, we examined the role of autophagy in PUUV-Hok replication. PUUV-Hok infection induced the expression of LC3-II, an autophagosome marker, and the nucleocapsid protein (NP) of PUUV-Hok was colocalized with punctate structures of LC3. Inhibition of autophagy using an siRNA for Atg5, an autophagy-related gene, increased the replication of PUUV-Hok, whereas an autophagy inducer decreased its replication. Inhibition of lysosomal degradation increased the expression of NP and LC3-II. In summary, autophagy was induced by PUUV-Hok infection, which inhibited PUUV-Hok replication in a manner related to the degradation of the NP in lysosomes.
  • Shoko Nishiyama, Minato Hirano, Memi Muto, Mao Kambara, Naoto Ito, Shintaro Kobayashi, Hiroaki Kariwa, Kentaro Yoshii
    Microbiology and immunology 66 (5) 234 - 237 2022/05 [Refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) is a zoonotic virus that causes encephalitis in humans. Various deletions have been reported in a variable region of the 3' untranslated region of the TBEV genome. This study analyzed the role of a Y-shaped secondary structure in the pathogenicity of TBEV by using reverse genetics. Deletion of the structure increased the mortality rate of virus-infected mice but did not affect the virus multiplication in cultured cells and organs. The results indicate that the secondary structure is involved in the regulation of TBEV pathogenesis.
  • Yuji Takahashi, Shintaro Kobayashi, Ryo Nakao, Hiroaki Kariwa, Kentaro Yoshii
    Ticks and tick-borne diseases 13 (2) 101900 - 101900 2022/03 [Refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) is a zoonotic virus belonging to the genus Flavivirus of the family Flaviviridae, causing meningitis or meningoencephalitis in humans. TBEV is widely distributed across the Eurasian northern regions, including Japan. Dogs have been reported to be sentinel hosts of TBEV in endemic areas, but studies of ticks infesting dogs are limited in Japan. This study isolated a novel TBEV strain from a tick (Ixodes ovatus) collected on a dog from central Hokkaido. Whole-genome sequencing revealed that the isolated strain belonged to the Far Eastern subtype of TBEV and was classified under a different subcluster of other Japanese isolates. Nanporo-18-44 showed growth properties similar to those of Oshima 5-10 both in vitro and in vivo. The pathogenicity of both viruses was similar in mice infected intracerebrally, however they showed a distinct distribution in the infected neurons of the mouse brain. Our results suggest that infections of humans and animals by unknown strains of TBEV exist in other areas of Japan. Further surveys including those conducted outside of Hokkaido, are required to elucidate the epidemiological risk of TBEV in Japan.
  • Kentaro Uemura, Haruaki Nobori, Akihiko Sato, Takao Sanaki, Shinsuke Toba, Michihito Sasaki, Akiho Murai, Noriko Saito-Tarashima, Noriaki Minakawa, Yasuko Orba, Hiroaki Kariwa, William W Hall, Hirofumi Sawa, Akira Matsuda, Katsumi Maenaka
    iScience 24 (10) 103120 - 103120 2021/10/22 [Refereed][Not invited]
     
    Newly emerging or re-emerging viral infections continue to cause significant morbidity and mortality every year worldwide, resulting in serious effects on both health and the global economy. Despite significant drug discovery research against dengue viruses (DENVs) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), no fully effective and specific drugs directed against these viruses have been discovered. Here, we examined the anti-DENV activity of tubercidin derivatives from a compound library from Hokkaido University and demonstrated that 5-hydroxymethyltubercidin (HMTU, HUP1108) possessed both potent anti-flavivirus and anti-coronavirus activities at submicromolar levels without significant cytotoxicity. Furthermore, HMTU inhibited viral RNA replication and specifically inhibited replication at the late stages of the SARS-CoV-2 infection process. Finally, we demonstrated that HMTU 5'-triphosphate inhibited RNA extension catalyzed by the viral RNA-dependent RNA polymerase. Our findings suggest that HMTU has the potential of serving as a lead compound for the development of a broad spectrum of antiviral agents, including SARS-CoV-2.
  • Fumihiro Kodama, Hiroki Yamaguchi, Eunsil Park, Kango Tatemoto, Mariko Sashika, Ryo Nakao, Yurino Terauchi, Keita Mizuma, Yasuko Orba, Hiroaki Kariwa, Katsuro Hagiwara, Katsunori Okazaki, Akiko Goto, Rika Komagome, Masahiro Miyoshi, Takuya Ito, Kimiaki Yamano, Kentaro Yoshii, Chiaki Funaki, Mariko Ishizuka, Asako Shigeno, Yukari Itakura, Lesley Bell-Sakyi, Shunji Edagawa, Atsushi Nagasaka, Yoshihiro Sakoda, Hirofumi Sawa, Ken Maeda, Masayuki Saijo, Keita Matsuno
    Nature communications 12 (1) 5539 - 5539 2021/09/20 [Refereed][Not invited]
     
    The increasing burden of tick-borne orthonairovirus infections, such as Crimean-Congo hemorrhagic fever, is becoming a global concern for public health. In the present study, we identify a novel orthonairovirus, designated Yezo virus (YEZV), from two patients showing acute febrile illness with thrombocytopenia and leukopenia after tick bite in Hokkaido, Japan, in 2019 and 2020, respectively. YEZV is phylogenetically grouped with Sulina virus detected in Ixodes ricinus ticks in Romania. YEZV infection has been confirmed in seven patients from 2014-2020, four of whom were co-infected with Borrelia spp. Antibodies to YEZV are found in wild deer and raccoons, and YEZV RNAs have been detected in ticks from Hokkaido. In this work, we demonstrate that YEZV is highly likely to be the causative pathogen of febrile illness, representing the first report of an endemic infection associated with an orthonairovirus potentially transmitted by ticks in Japan.
  • Inactivation of SARS-CoV-2 by povidone-iodine products: implications for effective mouth rinsing and gargling
    Hiroaki Kariwa, Hirofumi Sawa, Shintaro Kobayashi
    The Japanese Journal of Veterinary Research 69 (3) 183 - 187 2021/09 [Refereed][Not invited]
  • Takuma Izumi, Yuhei Morioka, Syun-Ichi Urayama, Daisuke Motooka, Tomokazu Tamura, Takahiro Kawagishi, Yuta Kanai, Takeshi Kobayashi, Chikako Ono, Akinari Morinaga, Takahiro Tomiyama, Norifumi Iseda, Yukiko Kosai, Shoichi Inokuchi, Shota Nakamura, Tomohisa Tanaka, Kohji Moriishi, Hiroaki Kariwa, Tomoharu Yoshizumi, Masaki Mori, Yoshiharu Matsuura, Takasuke Fukuhara
    Viruses 13 (7) 2021/07/06 [Refereed][Not invited]
     
    Although viruses infect various organs and are associated with diseases, there may be many unidentified pathogenic viruses. The recent development of next-generation sequencing technologies has facilitated the establishment of an environmental viral metagenomic approach targeting the intracellular viral genome. However, an efficient method for the detection of a viral genome derived from an RNA virus in animal or human samples has not been established. Here, we established a method for the efficient detection of RNA viruses in human clinical samples. We then tested the efficiency of the method compared to other conventional methods by using tissue samples collected from 57 recipients of living donor liver transplantations performed between June 2017 and February 2019 at Kyushu University Hospital. The viral read ratio in human clinical samples was higher by the new method than by the other conventional methods. In addition, the new method correctly identified viral RNA from liver tissues infected with hepatitis C virus. This new technique will be an effective tool for intracellular RNA virus surveillance in human clinical samples and may be useful for the detection of new RNA viruses associated with diseases.
  • Keisuke Maezono, Shintaro Kobayashi, Koshiro Tabata, Kentaro Yoshii, Hiroaki Kariwa
    Scientific reports 11 (1) 9213 - 9213 2021/04/28 [Refereed][Not invited]
     
    West Nile virus (WNV), a member of the Japanese encephalitis virus (JEV) serocomplex group, causes lethal encephalitis in humans and horses. Because serodiagnosis of WNV and JEV is hampered by cross-reactivity, the development of a simple, secure, and WNV-specific serodiagnostic system is required. The coexpression of prM protein and E protein leads to the secretion of subviral particles (SPs). Deletion of the C-terminal region of E protein is reported to affect the production of SPs by some flaviviruses. However, the influence of such a deletion on the properties and antigenicity of WNV E protein is unclear. We analyzed the properties of full-length E protein and E proteins lacking the C-terminal region as novel serodiagnostics for WNV infection. Deletion of the C-terminal region of E protein suppressed the formation of SPs but did not affect the production of E protein. The sensitivity of an enzyme-linked immunosorbent assay (ELISA) using the full-length E protein was higher than that using the truncated E proteins. Furthermore, in the ELISA using full-length E protein, there was little cross-reactivity with anti-JEV antibodies, and the sensitivity was similar to that of the neutralization test.
  • Mai Kishimoto, Kentaro Uemura, Takao Sanaki, Akihiko Sato, William W Hall, Hiroaki Kariwa, Yasuko Orba, Hirofumi Sawa, Michihito Sasaki
    Viruses 13 (3) 2021/02/28 [Refereed][Not invited]
     
    Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) utilizes host proteases, including a plasma membrane-associated transmembrane protease, serine 2 (TMPRSS2) to cleave and activate the virus spike protein to facilitate cellular entry. Although TMPRSS2 is a well-characterized type II transmembrane serine protease (TTSP), the role of other TTSPs on the replication of SARS-CoV-2 remains to be elucidated. Here, we have screened 12 TTSPs using human angiotensin-converting enzyme 2-expressing HEK293T (293T-ACE2) cells and Vero E6 cells and demonstrated that exogenous expression of TMPRSS11D and TMPRSS13 enhanced cellular uptake and subsequent replication of SARS-CoV-2. In addition, SARS-CoV-1 and SARS-CoV-2 share the same TTSPs in the viral entry process. Our study demonstrates the impact of host TTSPs on infection of SARS-CoV-2, which may have implications for cell and tissue tropism, for pathogenicity, and potentially for vaccine development.
  • ウエストナイルウイルス感染の特異性の高い新規血清診断系の開発
    前園 佳祐, 小林 進太郎, 好井 健太朗, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 163回 253 - 253 1347-8621 2020/10
  • 抗核蛋白質抗体を用いた各種ハンタウイルス抗原の新規検出法の確立
    三橋 健斗, 小林 進太郎, 好井 健太朗, 吉松 組子, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 163回 253 - 253 1347-8621 2020/10
  • ウエストナイルウイルス感染で認められるユビキチンの蓄積に関わるウイルス因子の特定
    小林 進太郎, 川上 怜子, 好井 健太朗, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 163回 261 - 261 1347-8621 2020/10
  • siRNAによるダニ媒介性フラビウイルスの増殖抑制の検討
    深野 紗代, 小林 進太郎, 苅和 宏明, 好井 健太朗
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 163回 261 - 261 1347-8621 2020/10
  • Yuji Takahashi, Shintaro Kobayashi, Mariko Ishizuka, Minato Hirano, Memi Muto, Shoko Nishiyama, Hiroaki Kariwa, Kentaro Yoshii
    The Journal of general virology 101 (5) 497 - 509 2020/05 [Refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) is a zoonotic virus in the genus Flavivirus, family Flaviviridae. TBEV is widely distributed in northern regions of the Eurasian continent, including Japan, and causes severe encephalitis in humans. Tick-borne encephalitis (TBE) was recently reported in central Hokkaido, and wild animals with anti-TBEV antibodies were detected over a wide area of Hokkaido, although TBEV was only isolated in southern Hokkaido. In this study, we conducted a survey of ticks to isolate TBEV in central Hokkaido. One strain, designated Sapporo-17-Io1, was isolated from ticks (Ixodes ovatus) collected in Sapporo city. Sequence analysis revealed that the isolated strain belonged to the Far Eastern subtype of TBEV and was classified in a different subcluster from Oshima 5-10, which had previously been isolated in southern Hokkaido. Sapporo-17-Io1 showed similar growth properties to those of Oshima 5-10 in cultured cells and mouse brains. The mortality rate of mice infected intracerebrally with each virus was similar, but the survival time of mice inoculated with Sapporo-17-Io1 was significantly longer than that of mice inoculated with Oshima 5-10. These results indicate that the neurovirulence of Sapporo-17-Io1 was lower than that of Oshima 5-10. Using an infectious cDNA clone, the replacement of genes encoding non-structural genes from Oshima 5-10 with those from Sapporo-17-Io1 attenuated the neuropathogenicity of the cloned viruses. This result indicated that the non-structural proteins determine the neurovirulence of these two strains. Our results provide important insights for evaluating epidemiological risk in TBE-endemic areas of Hokkaido.
  • Shintaro Kobayashi, Chisato Kaneko, Ryoko Kawakami, Rie Hasebe, Hirofumi Sawa, Kentaro Yoshii, Hiroaki Kariwa
    Scientific reports 10 (1) 7168 - 7168 2020/04/28 [Refereed][Not invited]
     
    West Nile virus (WNV) is an important cause of viral encephalitis in birds and animals, including humans. Amino acid 159 of the envelope (E) protein is reportedly implicated in the different levels of neurovirulence in mice infected with WNV NY99 or Eg101. We investigated the role of amino acid 159 of the E protein in the pathogenesis of WNV infection. We produced recombinant WNV with the structural proteins of the NY99 or Eg101 strain (NY-WT or EgCME-WT) and mutant viruses with substitutions of amino acid 159 of the E protein (NY-E-V159I or EgCME-E-I159V). The NY-WT and NY-E-V159I or EgCME-WT and EgCME-E-I159V titers in culture supernatant were similar. The mortality rate and viral titer in the brains of mice inoculated intraperitoneally with NY-WT or NY-E-V159I were also similar. In contrast, the mortality rate and viral titer in the brains of mice inoculated intracranially with EgCME-E-I159V were significantly higher than those of mice inoculated with EgCME-WT. The numbers of CD3-positive and CD8-positive T cells were greater in brains inoculated with EgCME-E-I159V than in those inoculated with EgCME-WT. Therefore, amino acid 159 of the E protein modulates the pathogenicity of WNV by affecting viral replication and T-cell infiltration in the brain.
  • Jan Clement, Clas Ahlm, Tatjana Avšič-Županc, Jason Botten, Kartik Chandran, Colleen B Jonsson, Hiroaki Kariwa, Jonas Klingström, Boris Klempa, Detlev H Krüger, Herwig Leirs, Dexin Li, Mifang Liang, Alemka Markotić, Anna Papa, Connie S Schmaljohn, Nicole D Tischler, Rainer G Ulrich, Antti Vaheri, Cecilia Vial, Richard Yanagihara, Piet Maes
    Antiviral research 176 104733 - 104733 2020/04 [Not refereed][Invited]
     
    The 2019 11th International Conference on Hantaviruses (ICH 2019) was organized by the International Society for Hantaviruses (ISH), and held on September 1-4, 2019, at the Irish College, in Leuven, Belgium. These ICHs have been held every three years since 1989. ICH 2019 was attended by 158 participants from 33 countries. The current report summarizes research presented on all aspects of hantavirology: ecology; pathogenesis and immune responses; virus phylogeny, replication and morphogenesis; epidemiology; vaccines, therapeutics and prevention; and clinical aspects and diagnosis.
  • Taishi Kidaka, Sithumini M.W. Lokupathirage, Bungiriye Devinda Shameera Muthusinghe, Boniface Lombe Pongombo, Christida Estu Wastika, Zhouxing Wei, Shizuka Yoshioka, Mayumi Ishizuka, Yoshihiro Sakoda, Hiroaki Kariwa, Norikazu Isoda
    Japanese Journal of Veterinary Research 68 (3) 133 - 150 0047-1917 2020 [Refereed][Not invited]
     
    An outbreak of novel coronavirus infection occurred in China at the end of 2019, which was designated as coronavirus disease 2019 (COVID-19), and spread to regions across Asia and ultimately all over the world. As of 21 May 2020, a total of more than 5 million cases with more than 350 thousand deaths were reported worldwide. Evaluation of the pathogenicity of the disease and determining the efficacy of control measures are essential for rapid containment of the disease. However, the world is facing difficulties in controlling COVID-19 at both of the national and global levels due to variations in pathogenicity of infection by severe acute respiratory syndrome coronavirus 2, the causal agent of COVID-19, and to diverse measures applied in each country based on their control capacities and policies. In the present review, we summarize the basic information and findings related to the COVID-19 pandemic, including pathogen agent, epidemiology, disease transmission, and clinical manifestations. Diagnosis, treatment, and preventive measures applied or under development all over the world are also reviewed to provide the opportunity to establish a more effective scenario for disease containment. Humanity has progressed by developing countless great technologies and immense scientific theories, however it may be a fact that we cannot conquer all risks to humanity. New findings and challenges for the unprecedented pandemic at the global level, such as COVID-19, should also contribute to preparedness for unknown diseases in future, similar to the lessons learnt from severe acute respiratory syndrome and the pandemic A(H1N1)pdm09 influenza.
  • Shintaro Kobayashi, Kentaro Yoshii, Wallaya Phongphaew, Memi Muto, Minato Hirano, Yasuko Orba, Hirofumi Sawa, Hiroaki Kariwa
    PLoS pathogens 16 (1) e1008238  2020/01 [Refereed][Not invited]
     
    West Nile virus (WNV) belongs to the Flaviviridae family and has emerged as a significant cause of viral encephalitis in birds and animals including humans. WNV replication directly induces neuronal injury, followed by neuronal cell death. We previously showed that accumulation of ubiquitinated protein aggregates was involved in neuronal cell death in the WNV-infected mouse brain. In this study, we attempted to elucidate the mechanisms of the accumulation of protein aggregates in the WNV-infected cells. To identify the viral factor inducing the accumulation of ubiquitinated proteins, intracellular accumulation of ubiquitinated proteins was examined in the cells expressing the viral protein. Expression of capsid (C) protein induced the accumulation, while mutations at residues L51 and A52 in C protein abrogated the accumulation. Wild-type (WT) or mutant WNV in which mutations were introduced into the residues was inoculated into human neuroblastoma cells. The expression levels of LC3-II, an autophagy-related protein, and AMP-activated protein kinase (AMPK), an autophagy inducer, were reduced in the cells infected with WT WNV, while the reduction was not observed in the cells infected with WNV with the mutations in C protein. Similarly, ubiquitination and degradation of AMPK were only observed in the cells infected with WT WNV. In the cells expressing C protein, AMPK was co-precipitated with C protein and mutations in L51 and A52 reduced the interaction. Although the viral replication was not affected, the accumulation of ubiquitinated proteins in brain and neurological symptoms were attenuated in the mouse inoculated with WNV with the mutations in C protein as compared with that with WT WNV. Taken together, ubiquitination and degradation of AMPK by C protein resulted in the inhibition of autophagy and the accumulation of protein aggregates, which contributes to the development of neurological disease.
  • Christida E Wastika, Michihito Sasaki, Kentaro Yoshii, Paulina D Anindita, Bernard M Hang'ombe, Aaron S Mweene, Shintaro Kobayashi, Hiroaki Kariwa, Michael J Carr, William W Hall, Yuki Eshita, Yasuko Orba, Hirofumi Sawa
    Archives of virology 164 (8) 2165 - 2170 0304-8608 2019/08 [Refereed][Not invited]
     
    Zika virus (ZIKV) circulation occurs between non-human primates (NHPs) in a sylvatic transmission cycle. To investigate evidence of flavivirus infection in NHPs in Zambia, we performed a plaque reduction neutralization test (PRNT) to quantify neutralizing antibodies. PRNT revealed that sera from NHPs (African green monkeys and baboons) exhibited neutralizing activity against ZIKV (34.4%; 33/96), whereas a PRNT for yellow fever virus using NHP sera showed no neutralization activity. ZIKV genomic RNA was not detected in splenic tissues from NHPs, suggesting that the presence of anti-ZIKV neutralizing antibodies represented resolved infections. Our evidence suggests that ZIKV is maintained in NHP reservoirs in Zambia.
  • Jamsransuren, Dulamjav, Yoshii, Kentaro, Kariwa, Hiroaki, Asakawa, Mitsuhiko, Okuda, Kei, Fujii, Kei, Fukumoto, Shinya, Umemiya-Shirafuji, Rika, Sasaki, Motoki, Matsumoto, Kotaro, Yamaguchi, Emi, Ogawa, Haruko, Imai, Kunitoshi
    Japanese Journal of Veterinary Research 67 (2) 163 - 172 0047-1917 2019/05 [Refereed][Not invited]
     
    The first human case of tick-borne encephalitis (TBE) in Japan was recorded in southern Hokkaido in 1993 and was followed by four further cases in southern, central, and northern Hokkaido during 20162018. However, the distribution of TBE virus (TBEV) foci in Japan is unclear. Therefore, here, we serologically examined raccoons (Procyon lotor), sika deer (Cervus nippon), and wild boars (Sus scrofa) as sentinels of TBEV infection in Hokkaido and in Fukushima and Tochigi Prefectures in Honshu. A total of 1,649 serum samples collected between 2003 and 2018 were screened by enzyme-linked immunosorbent assay using subviral particles and confirmed using the virus neutralization test. In raccoons, the seroprevalence of TBEV was 5.9% (39/662 samples) in central Hokkaido in 2003-2005 and 0.8% (3/368 samples) in eastern Hokkaido in 2010-2018, revealing the presence of TBEV foci in these areas. In addition, 0.5% (2/414) of deer sampled in eastern Hokkaido in 2010-2017 and 2.4% (1/42) of deer sampled in Tochigi Prefecture in 2016-2018 were seropositive. On Honshu, seropositive rodents have previously been detected only in Shimane Prefecture. Therefore, the detection of seropositive animals in Tochigi Prefecture may indicate the widespread distribution of TBEV foci throughout Japan. TBEV and viral genes were not detected in 507 ticks collected in the same area of eastern Hokkaido where seropositive animals were found, reemphasizing the value of using serological examination of wild animals as a tool for revealing unknown TBE risk areas. Our findings also indicate that raccoons may be particularly useful sentinels.
  • Tapiwa Lundu, Kentaro Yoshii, Shintaro Kobayashi, Shigeru Morikawa, Toshio Tsubota, Naoaki Misawa, Daisuke Hayasaka, Hiroaki Kariwa
    Japanese Journal of Veterinary Research 66 (1) 21 - 28 0047-1917 2018 [Refereed][Not invited]
     
    Severe fever with thrombocytopenia syndrome (SFTS) is a newly recognized zoonosis that occurs in China, Japan, and South Korea and is caused by the SFTS virus (SFTSV), which is in the genus Phlebovirus, family Phenuiviridae. Since its discovery in Japan in 2013, SFTS has been reported in the western parts of the country. To elucidate the distribution of SFTSV, we conducted a serological survey of deer and rodents. Serum was screened using enzyme-linked immunosorbent assay (ELISA) and suspected cases were further tested with an indirect immunofluorescence antibody (IFA) assay. Serum samples from 315 deer from Hokkaido (non-endemic area), 41 deer from Miyazaki (endemic area), and 910 rodents from six locations in Japan were tested. Of the 41 deer from Miyazaki, 2 (4.9%) had high ELISA optical density (OD) values (0.1 < OD < 0.3) and a positive IFA result. All of the deer samples from Hokkaido were negative by ELISA (OD < 0.1). No SFTSV-positive rodents were found. Our results indicate that deer in Miyazaki were exposed to SFTSV, unlike deer from Hokkaido (P < 0.05).
  • Tapiwa Lundu, Yoshimi Tsuda, Ryo Ito, Kenta Shimizu, Shintaro Kobayashi, Kentaro Yoshii, Kumiko Yoshimatsu, Jiro Arikawa, Hiroaki Kariwa
    Biomedical research (Tokyo, Japan) 39 (1) 27 - 38 0388-6107 2018 [Refereed][Not invited]
     
    Severe fever with thrombocytopenia syndrome phlebovirus (SFTSV) is a newly emerged phlebovirus identified in China, Japan, and South Korea. Phlebovirus glycoproteins (GP) play a key role in targeting viral structural components to the budding compartments in the ER-Golgi intermediate compartment (ERGIC) and Golgi complex. However, the role of SFTSV GP in targeting structural proteins to the ERGIC and Golgi complex remains unresolved. In this study, we show that SFTSV GP plays a significant role in targeting RNA-dependent RNA polymerase (L) and nucleocapsid protein (NP) to the budding sites. Confocal microscopy was used to investigate the subcellular localization of SFTSV structural proteins. In SFTSV-infected cells, GP and L localized to the ER, ERGIC and Golgi complex, whereas NP localized to the ERGIC and Golgi complex. In addition, GP colocalized with L and NP in infected cells. In cells singly transfected with GP, L or NP, GP localized to the same subcellular compartments as in infected cells. However, L or NP alone did not localize to the ER, ERGIC, or Golgi complex. Cotransfection experiments showed that GP altered the localization of L to the ERGIC and Golgi complex but not that of NP. Interestingly, plasmid-expressed NP fused with a hemagglutinin tag localized to the ERGIC and Golgi complex when expressed in SFTSV-infected cells and colocalised with GP, suggesting that GP plays a role in the subcellular localization of L and NP in infected cells. Thus, the SFTSV structural components start to assemble at the ERGIC to Golgi complex. GP is required for transporting L and NP to the ERGIC and Golgi complex. In addition, targeting of NP requires interaction with other factors besides GP.
  • Ludek Eyer, Hirofumi Kondo, Darina Zouharova, Minato Hirano, James J Valdés, Memi Muto, Tomas Kastl, Shintaro Kobayashi, Jan Haviernik, Manabu Igarashi, Hiroaki Kariwa, Marketa Vaculovicova, Jiri Cerny, Rene Kizek, Andrea Kröger, Stefan Lienenklaus, Milan Dejmek, Radim Nencka, Martin Palus, Jiri Salat, Erik De Clercq, Kentaro Yoshii, Daniel Ruzek
    Journal of virology 91 (21) 0022-538X 2017/11/01 [Refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) causes a severe and potentially fatal neuroinfection in humans. Despite its high medical relevance, no specific antiviral therapy is currently available. Here we demonstrate that treatment with a nucleoside analog, 7-deaza-2'-C-methyladenosine (7-deaza-2'-CMA), substantially improved disease outcomes, increased survival, and reduced signs of neuroinfection and viral titers in the brains of mice infected with a lethal dose of TBEV. To investigate the mechanism of action of 7-deaza-2'-CMA, two drug-resistant TBEV clones were generated and characterized. The two clones shared a signature amino acid substitution, S603T, in the viral NS5 RNA-dependent RNA polymerase (RdRp) domain. This mutation conferred resistance to various 2'-C-methylated nucleoside derivatives, but no cross-resistance was seen with other nucleoside analogs, such as 4'-C-azidocytidine and 2'-deoxy-2'-beta-hydroxy-4'-azidocytidine (RO-9187). All-atom molecular dynamics simulations revealed that the S603T RdRp mutant repels a water molecule that coordinates the position of a metal ion cofactor as 2'-C-methylated nucleoside analogs approach the active site. To investigate its phenotype, the S603T mutation was introduced into a recombinant TBEV strain (Oshima-IC) generated from an infectious cDNA clone and into a TBEV replicon that expresses a reporter luciferase gene (Oshima-REP-luc2A). The mutants were replication impaired, showing reduced growth and a small plaque size in mammalian cell culture and reduced levels of neuroinvasiveness and neurovirulence in rodent models. These results indicate that TBEV resistance to 2'-C-methylated nucleoside inhibitors is conferred by a single conservative mutation that causes a subtle atomic effect within the active site of the viral NS5 RdRp and is associated with strong attenuation of the virus.IMPORTANCE This study found that the nucleoside analog 7-deaza-2'-C-methyladenosine (7-deaza-2'-CMA) has high antiviral activity against tick-borne encephalitis virus (TBEV), a pathogen that causes severe human neuroinfections in large areas of Europe and Asia and for which there is currently no specific therapy. Treating mice infected with a lethal dose of TBEV with 7-deaza-2'-CMA resulted in significantly higher survival rates and reduced the severity of neurological signs of the disease. Thus, this compound shows promise for further development as an anti-TBEV drug. It is important to generate drug-resistant mutants to understand how the drug works and to develop guidelines for patient treatment. We generated TBEV mutants that were resistant not only to 7-deaza-2'-CMA but also to a broad range of other 2'-C-methylated antiviral medications. Our findings suggest that combination therapy may be used to improve treatment and reduce the emergence of drug-resistant viruses during nucleoside analog therapy for TBEV infection.
  • Minato Hirano, Memi Muto, Mizuki Sakai, Hirofumi Kondo, Shintaro Kobayashi, Hiroaki Kariwa, Kentaro Yoshii
    Proceedings of the National Academy of Sciences of the United States of America 114 (37) 9960 - 9965 0027-8424 2017/09/12 [Refereed][Not invited]
     
    Neurological diseases caused by encephalitic flaviviruses are severe and associated with high levels of mortality. However, little is known about the detailed mechanisms of viral replication and pathogenicity in the brain. Previously, we reported that the genomic RNA of tick-borne encephalitis virus (TBEV), a member of the genus Flavivirus, is transported and replicated in the dendrites of neurons. In the present study, we analyzed the transport mechanism of the viral genome to dendrites. We identified specific sequences of the 5' untranslated region of TBEV genomic RNA that act as a cis-acting element for RNA transport. Mutated TBEV with impaired RNA transport in dendrites caused a reduction in neurological symptoms in infected mice. We show that neuronal granules, which regulate the transport and local translation of dendritic mRNAs, are involved in TBEV genomic RNA transport. TBEV genomic RNA bound an RNA-binding protein of neuronal granules and disturbed the transport of dendritic mRNAs. These results demonstrated a neuropathogenic virus hijacking the neuronal granule system for the transport of viral genomic RNA in dendrites, resulting in severe neurological disease.
  • Shintaro Kobayashi, Kentaro Yoshii, Minato Hirano, Memi Muto, Hiroaki Kariwa
    Journal of virological methods 240 14 - 20 0166-0934 2017/02 [Refereed][Not invited]
     
    Reverse genetics systems facilitate investigation of many aspects of the life cycle and pathogenesis of viruses. However, genetic instability in Escherichia coli has hampered development of a reverse genetics system for West Nile virus (WNV). In this study, we developed a novel reverse genetics system for WNV based on homologous recombination in mammalian cells. Introduction of the DNA fragment coding for the WNV structural protein together with a DNA-based replicon resulted in the release of infectious WNV. The growth rate and plaque size of the recombinant virus were almost identical to those of the parent WNV. Furthermore, chimeric WNV was produced by introducing the DNA fragment coding for the structural protein and replicon plasmid derived from various strains. Here, we report development of a novel system that will facilitate research into WNV infection.
  • Hiroaki Kariwa
    Uirusu 67 (1) 25 - 32 0042-6857 2017 [Refereed][Not invited]
     
    Hantaviruses belongs to the genus Hantavirus in the family Bunyaviridae are maintained in rodents and infects to humans by inhalation of the aerosol of infected rodent excreta. In this article, the epidemiology of hantavirus infection and the special relationship between rodent and hantavirus are described. Hantavirus infections include hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). HFRS is characterized high fever, hemorrhage, and renal disorder. HFRS is distributed in East Asia, Europe, and Russia. While HCPS is characterized acute respiratory dysfunction and cardiogenic shock. The distribution of HCPS is limited in North and South Americas. In Japan's neighboring countries, such as Russia, China, and Korea, large numbers of HFRS patients are reported in association with multiple hantaviruses. In Japan, hantavirus infection has not been reported since 1985 but grey red-backed vole (Myodes rufocanus bedfordiae) inhabiting Hokkaido maintain one of the hantaviruses. Coevolution between hantavirus and host may have been occurred during a long period. The endemic areas of hantavirus infection are strongly associated with the distribution of host animal carrying pathogenic hantaviruses.
  • Targeting of severe fever with thrombocytopenia syndrome virus structural proteins to the ERGIC (endoplasmic reticulum Golgi intermediate compartment) and Golgi complex.
    Lundu T, Tsuda Y, Ito R, Shimizu K, Kobayashi S, Yoshii K, Yoshimatsu K, Arikawa J, Kariwa H
    Biomed Res-Tokyo 78 (8) 1453 - 1460 2017 [Refereed][Not invited]
  • HokkaidoウイルスとPuumalaウイルスの遺伝子再集合体の作出とその性状解析
    岩崎 里菜, 真田 崇弘, 好井 健太朗, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 157回 439 - 439 1347-8621 2014/08 [Refereed][Not invited]
  • 初代培養マウス脳細胞を用いた脳炎フラビウイルスの増殖機構の解析
    平野 港, 好井 健太朗, 境 瑞樹, 長谷部 理絵, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 156回 302 - 302 1347-8621 2013/08 [Refereed][Not invited]
  • 極東型ダニ媒介性脳炎ウイルスの強毒化に関わるウイルス側因子の特定
    境 瑞紀, 好井 健太朗, 寸田 祐嗣, 横澤 香菜, 平野 港, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 156回 303 - 303 1347-8621 2013/08 [Refereed][Not invited]
  • 新世界ハンタウイルス感染のためのハンタウイルス組み換え核蛋白を用いた血清型鑑別ELISA法の開発
    駒 貴明, 吉松 組子, 垂石 みどり, 宮下 大輔, 遠藤 理香, 清水 健太, 安田 俊平, 天田 貴子, 瀬戸 隆, 村田 亮, 吉田 喜香, 苅和 宏明, 高島 郁夫, 有川 二郎
    北海道医学雑誌 88 (1) 35 - 35 2013/01 [Not refereed][Not invited]
  • ダニ媒介性フラビウイルスによる中枢神経系障害に関わるウイルス因子の同定
    好井 健太朗, 寸田 祐嗣, 境 瑞紀, 苅和 宏明, Holbrook Michael, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 154回 264 - 264 1347-8621 2012/08 [Refereed][Not invited]
  • 極東型ダニ媒介性脳炎ウイルスの強毒化に関わるウイルス側因子の特定
    境 瑞紀, 好井 健太朗, 横澤 香菜, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 154回 264 - 264 1347-8621 2012/08 [Refereed][Not invited]
  • ダニ媒介性フラビウイルスのインターフェロンアンタゴニスト作用の解析
    鶴田 征太郎, 好井 健太朗, 境 瑞紀, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 154回 264 - 264 1347-8621 2012/08 [Refereed][Not invited]
  • 新たに分離されたHokkaidoウイルスの性状解析
    真田 崇弘, 尾崎 由佳, 瀬戸 隆弘, 中尾 桃子, Saasa Ngonda, 吉松 組子, 有川 二郎, 好井 健太朗, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 154回 265 - 265 1347-8621 2012/08 [Refereed][Not invited]
  • 好井健太朗, 山崎翔子, 持舘景太, 苅和宏明, 高島郁夫
    獣医畜産新報 (1090) 377-378  0447-0192 2012/05/01 [Not refereed][Not invited]
  • 好井 健太朗, 持舘 景太, 苅和 宏明
    獣医畜産新報 文永堂出版 64 (10) 801 - 803 0447-0192 2011/10 [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのE蛋白糖鎖は哺乳動物細胞におけるウイルス粒子分泌に影響する
    柳原 なつみ, 好井 健太朗, 後藤 明子, 伊川 綾恵, 石塚 万里子, 苅和 宏明, 高島 郁夫
    北海道獣医師会雑誌 (公社)北海道獣医師会 55 (8) 415 - 415 0018-3385 2011/08 [Refereed][Not invited]
  • 2008年北海道で分離されたダニ媒介性脳炎ウイルスOshima 08-AS株の病原性解析
    山崎 翔子, 好井 健太朗, 真田 崇弘, 苅和 宏明, 高島 郁夫
    北海道獣医師会雑誌 (公社)北海道獣医師会 55 (8) 416 - 416 0018-3385 2011/08 [Refereed][Not invited]
  • 2008年北海道で分離されたダニ媒介性脳炎ウイルスOshima 08-AS株の病原性解析
    山崎 翔子, 好井 健太朗, 真田 崇弘, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 152回 255 - 255 1347-8621 2011/08 [Refereed][Not invited]
  • 野生マウス由来Oas遺伝子座導入コンジェニックマウスにおけるダニ媒介性脳炎ウイルスの神経病原性の解析
    好井 健太朗, 森藤 可南子, 永田 典代, 佐々木 宣哉, 苅和 宏明, 安居院 高志, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 152回 256 - 256 1347-8621 2011/08 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのE蛋白糖鎖は哺乳動物細胞におけるウイルス粒子分泌に影響する
    柳原 なつみ, 好井 健太朗, 石塚 万里子, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 152回 256 - 256 1347-8621 2011/08 [Refereed][Not invited]
  • エゾヤチネズミ(Myodes rufocanus)の腎臓由来細胞系の確立とHokkaidoウイルス分離への応用
    真田 崇弘, 瀬戸 隆弘, 尾崎 由佳, Ngonda Saasa, 好井 健太朗, 苅和 宏明
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 152回 256 - 256 1347-8621 2011/08 [Refereed][Not invited]
  • 苅和 宏明, 好井 健太朗, 高島 郁夫
    公衆衛生 医学書院 75 (1) 36 - 38 0368-5187 2011/01 [Not refereed][Not invited]
  • 2008年北海道におけるダニ媒介性脳炎ウイルスの分離と性状解析
    山崎 翔子, 好井 健太朗, 持舘 景太, 村田 亮, 真田 崇弘, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 247 - 247 1347-8621 2010/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのE蛋白の糖鎖付加がウイルス性状に与える影響
    柳原 なつみ, 好井 健太朗, 後藤 明子, 伊川 綾恵, 石塚 万里子, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 248 - 248 1347-8621 2010/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスSofjin株の感染性cDNAの構築
    高野 絢子, 大森 優紀, 好井 健太朗, 横澤 香菜, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 248 - 248 1347-8621 2010/09 [Refereed][Not invited]
  • ダニ媒介性脳炎/オムスク出血熱のキメラウイルスの作成と性状解析
    好井 健太朗, 寸田 祐嗣, 苅和 宏明, Holbrook Michael, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 248 - 248 1347-8621 2010/09 [Refereed][Not invited]
  • メキシコ由来のハンタウイルスに対するモノクローナル抗体の作出と各種ハンタウイルスに対する反応性の検討
    吉田 喜香, 苅和 宏明, 真田 崇弘, Saasa Ngonda, 瀬戸 隆弘, 吉松 組子, 有川 二郎, 好井 健太朗, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 249 - 249 1347-8621 2010/09 [Refereed][Not invited]
  • Puumalaウイルスを感染させたシリアンハムスター(Mesocricetus auratus)の感染動態の解析
    真田 崇弘, 苅和 宏明, 谷川 洋一, Nur Hardy Abu Daud, 瀬戸 隆弘, 永田 典代, 吉松 組子, 有川 二郎, 好井 健太朗, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 150回 252 - 252 1347-8621 2010/09 [Refereed][Not invited]
  • 村田亮, 好井健太朗, 苅和宏明, 高島郁夫
    獣医畜産新報 (1064) 208-209  0447-0192 2010/03/01 [Not refereed][Not invited]
  • 好井健太朗, 苅和宏明, 高島郁夫
    北海道獣医師会雑誌 54 (1) 2-7  0018-3385 2010/01/10 [Not refereed][Not invited]
  • 日本国内におけるダニ媒介性脳炎の血清疫学調査
    持舘 景太, 好井 健太朗, 大森 優紀, 千葉 裕美子, 村田 亮, 真田 崇弘, 前田 潤子, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 148回 236 - 236 1347-8621 2009/09 [Refereed][Not invited]
  • 極東ロシアの野鳥におけるウエストナイル熱の血清疫学調査と中和試験の評価
    村田 亮, 橋口 和明, 好井 健太朗, 野田 寛, 伊川 綾恵, 原田 祐里, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 148回 236 - 236 1347-8621 2009/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスSofjin株のレプリコンの構築
    高野 絢子, 大森 優紀, 好井 健太朗, 石塚 万里子, 村田 亮, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 148回 236 - 236 1347-8621 2009/09 [Refereed][Not invited]
  • オムスク出血熱ウイルスの感染性cDNAの構築
    好井 健太朗, 苅和 宏明, 高島 郁夫, Holbrook Michael
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 148回 237 - 237 1347-8621 2009/09 [Refereed][Not invited]
  • メキシコの野生げっ歯類が保有するハンタウイルスの遺伝子解析
    吉田 喜香, 苅和 宏明, 高野 絢子, 戸谷 理詩, 宮下 大輔, Ngonda Saasa, 瀬戸 隆弘, 真田 崇弘, 吉川 佳佑, 好井 健太朗, 吉松 組子, 有川 次郎, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 148回 237 - 237 1347-8621 2009/09 [Refereed][Not invited]
  • 日本国内におけるダニ媒介性脳炎の血清疫学調査
    持舘 景太, 好井 健太朗, 大森 優紀, 千葉 裕美子, 村田 亮, 真田 崇弘, 前田 潤子, 苅和 宏明, 高島 郁夫
    北海道獣医師会雑誌 (公社)北海道獣医師会 53 (8) 111 - 111 0018-3385 2009/08 [Refereed][Not invited]
  • 極東ロシアの野鼠からのハンタウイルスの分離と人におけるウイルス感染状況の調査
    吉川 佳佑, 苅和 宏明, 瀬戸 隆弘, 真田 崇弘, 石塚 万里子, 吉松 組子, 有川 二郎, Ivanov Leonid, Slonova Raisa, 好井 健太朗, 高島 郁夫
    北海道獣医師会雑誌 (公社)北海道獣医師会 53 (8) 112 - 112 0018-3385 2009/08 [Refereed][Not invited]
  • 極東ロシアのげっ歯類からのハンタウイルスの分離とウイルス遺伝子の性状解析
    吉川 佳佑, 苅和 宏明, 瀬戸 隆弘, 真田 崇弘, 石塚 万里子, 吉松 組子, 有川 二郎, Ivanov Lenid, 好井 健太朗, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 147回 260 - 260 1347-8621 2009/03 [Refereed][Not invited]
  • ウエストナイル熱の血清診断法の評価と極東ロシアにおける疫学調査
    村田 亮, 橋口 和明, 好井 健太朗, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 146回 225 - 225 1347-8621 2008/09 [Refereed][Not invited]
  • 多種類のハンタウイルス血清型の検出が可能な抗原検出法の開発
    真田 崇弘, 苅和 宏明, 瀬戸 隆弘, 谷川 洋一, 宮下 大輔, 吉松 組子, 有川 二郎, 好井 健太朗, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 146回 225 - 225 1347-8621 2008/09 [Refereed][Not invited]
  • ウイルス様粒子を用いたダニ媒介性脳炎の新たな診断法の開発
    千葉 裕美子, 伊川 綾恵, 好井 健太朗, 大森 優紀, 村田 亮, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 146回 226 - 226 1347-8621 2008/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスの中空ウイルス様粒子のワクチンへの応用
    大森 優紀, 伊川 綾恵, 川上 和江, 好井 健太朗, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 146回 226 - 226 1347-8621 2008/09 [Refereed][Not invited]
  • SARSコロナウイルスのNおよびM蛋白質の粒子形成における機能解析
    中内 美名, 藤井 寛子, 苅和 宏明, 前田 秋彦, 好井 健太朗, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 145回 204 - 204 1347-8621 2008/03 [Refereed][Not invited]
  • ウエストナイルウイルスのE蛋白上糖鎖が宿主内におけるウイルス増殖に与える影響
    村田 亮, 好井 健太朗, 苅和 宏明, 江下 優樹, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 145回 205 - 205 1347-8621 2008/03 [Refereed][Not invited]
  • Arch Virol
    Nakamura, I, Yoshimatsu, K, Lee, B. H, Okumura, M, Taruishi, M, Araki, K, Kariwa, H, Takashima, I, Arikawa, J
    Development of a serotyping ELISA system for Thailand virus infection. 153 (1537) 1542  2008 [Not refereed][Not invited]
  • ウエストナイルウイルスのE蛋白上糖鎖付加がウイルス増殖に与える影響
    村田 亮, 好井 健太朗, 原田 祐里, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 144回 127 - 127 1347-8621 2007/08 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのウイルス様粒子およびその組換え発現プラスミドを抗原とした針無加圧式注射によるワクチン接種の有効性の検討
    大森 優紀, 伊川 綾恵, 川上 和江, 好井 健太朗, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 144回 128 - 128 1347-8621 2007/08 [Refereed][Not invited]
  • レプリコンを利用したウエストナイルウイルスとダニ媒介性脳炎ウイルスのキメラウイルス様粒子の作製
    原田 祐里, 好井 健太朗, 伊川 綾恵, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 142回 121 - 121 1347-8621 2006/08 [Refereed][Not invited]
  • 苅和宏明, 谷川洋一, 萩谷友洋, LOKUGAMAGE Kumari, LOKUGAMAGE Nandadeva, DAUD Nur Hardy Bin Abu, 好井健太朗, 高島郁夫
    獣医畜産新報 文永堂出版 59 (1021) 633-638 - 638 0447-0192 2006/08/01 [Not refereed][Not invited]
  • ウイルス様粒子を用いたフラビウイルスの粒子形成機構の解析,および診断法・予防法開発への応用
    好井 健太朗, 後藤 明子, 小原 真弓, 川上 和江, 伊川 綾江, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 141回 73 - 73 1347-8621 2006/03 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルス組み換え蛋白を用いたELISA法による野鼠血清スクリーニング法の開発
    伊川 綾恵, 好井 健太朗, 川上 和江, 後藤 明子, 小原 真弓, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 140回 147 - 147 1347-8621 2005/08 [Refereed][Not invited]
  • 高島 郁夫, 早坂 大輔, 後藤 明子, 好井 健太朗, 苅和 宏明
    ウイルス 日本ウイルス学会 55 (1) 35 - 44 0042-6857 2005/06 [Refereed][Not invited]
     
    北海道と極東ロシアのダニ媒介性脳炎ウイルスの系統解析の結果,北海道株は極東地区において数百年前に出現したと推定された.イルクーツク地区のダニ媒介性脳炎ウイルスはシベリア亜型と同定された.ダニ媒介性脳炎ウイルスのBHK細胞適応変異株はマウスにおける神経侵襲性毒力が低下していた.変異株はエンベロープ蛋白に1ヶ所のアミノ酸置換があり,荷電が陽性に変化する変異であった.変異株はウイルス血症と脾臓でのウイルス価が親株に比べ低下していた.ダニ媒介性脳炎ウイルスの感染性cDNAクローンの作製に成功し,神経毒力の解析を行った.エンベロープ蛋白の1ヶ所とNs5の2ヶ所のアミノ酸変異が相乗的に神経毒力の低下に関与していた(著者抄録)
  • 有川二郎, 吉松組子, KUMPERASART Sanit, THANG Truong Thua, 荒木幸一, LEE Byoung‐Hee, KRUGER Detlev H, 苅和宏明, 高島郁夫
    獣医畜産新報 (1005) 326 - 328 0447-0192 2005/04/01 [Not refereed][Not invited]
  • 野生げっ歯類からのハンタウイルス抗原検出用ELISAの開発
    谷川 洋一, 苅和 宏明, 萩谷 友洋, Lokugamage Nandadeva, Lokugamage Kumari, 舘 敦史, 好井 健太朗, 吉松 組子, 有川 二郎, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 139回 185 - 185 1347-8621 2005/03 [Refereed][Not invited]
  • フラビウイルスのウイルス粒子分泌におけるユビキチン-プロテアソーム系の関与
    好井 健太朗, 後藤 明子, 川上 和江, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 138回 129 - 129 1347-8621 2004/08 [Refereed][Not invited]
  • 日本におけるハンタウイルス感染の動物伝染病学的及び疫学的研究(Epizootiological and epidemiological study of hantavirus infection in Japan)
    Lokugamage Nandadeva, 苅和 宏明, 好井 健太朗, 舘 敦史, 安藤 秀二, 福島 博, 土屋 公幸, 岩崎 琢也, 吉松 組子, 有川 二郎, 高島 郁夫
    日本獣医学会学術集会講演要旨集 138回 130 - 130 1347-8621 2004/08 [Refereed][Not invited]
  • タイリクヤチネズミから分離されたPuumala型近縁ハンタウイルスの遺伝子解析
    谷川 洋一, 苅和 宏明, Lokugamage Nandadeva, 萩谷 友洋, Lokugamage Kumari, 舘 敦史, 好井 健太朗, 岩佐 真宏, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 138回 130 - 130 1347-8621 2004/08 [Refereed][Not invited]
  • Amur型ハンタウイルス糖蛋白の哺乳類細胞での発現と抗原性解析
    舘 敦史, 苅和 宏明, Lokugamage Kumari, Lokugamage Nandadeva, 谷川 洋一, 好井 健太朗, 吉松 組子, 有川 二郎, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 138回 131 - 131 1347-8621 2004/08 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルス組み替え蛋白を用いたELISAによる野ネズミ血清スクリーニング法の開発
    川上 和江, 好井 健太朗, 後藤 明子, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 137回 114 - 114 1347-8621 2004/03 [Refereed][Not invited]
  • repliconを利用したフラビウイルスのキメラウイルス様粒子の作成
    好井 健太朗, 早坂 大輔, 後藤 明子, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 137回 114 - 114 1347-8621 2004/03 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのE蛋白の糖鎖修飾がウイルス粒子分泌に与える影響
    後藤 明子, 好井 健太朗, 小原 真弓, 植木 智隆, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 137回 115 - 115 1347-8621 2004/03 [Refereed][Not invited]
  • Mizutani T., Eshita Y., Ako Y., Miyoshi H., Kariwa H., Takashima I.
    Medical Entomology and Zoology 日本衛生動物学会 55 56 - 56 2004
  • ダニ媒介性脳炎ウイルスの感染性cDNAクローンを用いた病原性解析
    植木 智隆, 早坂 大輔, 後藤 明子, 好井 健太朗, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 136回 176 - 176 1347-8621 2003/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのrepliconおよびpackaging systemの構築
    好井 健太朗, 早坂 大輔, 後藤 明子, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 136回 257 - 257 1347-8621 2003/09 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのエンベロープ糖蛋白の糖鎖欠損がウイルス粒子形成に与える影響
    後藤 明子, 好井 健太朗, 小原 真弓, 植木 智隆, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 135回 156 - 156 1347-8621 2003/03 [Refereed][Not invited]
  • Mizutani T., Kobayashi M., Eshita Y., Shirato K., Ako Y., Miyoshi H., Kariwa H., Takashima I.
    Medical Entomology and Zoology 日本衛生動物学会 54 24 - 24 2003
  • ダニ媒介性脳炎ウイルスのウイルス粒子放出抑制に関する解析
    好井 健太朗, 後藤 明子, 小原 真弓, 植木 智隆, 早坂 大輔, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 134回 195 - 195 1347-8621 2002/08 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルス神経侵入性弱毒変異株のマウス体内での動態
    後藤 明子, 好井 健太朗, 早坂 大輔, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 134回 195 - 195 1347-8621 2002/08 [Refereed][Not invited]
  • 北海道におけるダニ媒介性脳炎ウイルスの血清疫学調査
    小原 真弓, 好井 健太朗, 後藤 明子, 早坂 大輔, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 134回 195 - 195 1347-8621 2002/08 [Refereed][Not invited]
  • Daisuke Hayasaka, Akiko Goto, Kentaro Yoshii, Tetsuya Mizutani, Hiroaki Kariwa, Ikuo Takashima
    Vaccine 19 (32) 4774 - 4779 2001/09 [Not refereed][Not invited]
  • Araki K, Yoshimatsu K, Ogino M, Ebihara H, Lundkvist A, Kariwa H, Takashima I, Arikawa J
    Journal of clinical microbiology 7 39 2397 - 2404 0095-1137 2001/07 [Refereed][Not invited]
  • Arikawa J, Yoshimatsu K, Kariwa H
    Japanese journal of infectious diseases 3 54 95 - 102 1344-6304 2001/06 [Refereed][Not invited]
  • Daisuke Hayasaka, Leonid Ivanov, Galina N. Leonova, Akiko Goto, Kentaro Yoshii, Tetsuya Mizutani, Hiroaki Kariwa, Ikuo Takashima
    J. Gen. Virol. Society for General Microbiology. 82 (Pt6) 1319 - 1328 0022-1317 2001/06 [Not refereed][Not invited]
     
    In this study, tick-borne encephalitis (TBE) viruses from Siberia and far-eastern Asia were characterized in order to determine virus subtype distribution. TBE viruses were isolated from ticks (Ixodes persulcatus) collected in the far-eastern (Khabarovsk and Vladivostok) and Siberian (Irkutsk) regions of Russia in 1999. Phylogenetic analysis showed that isolates formed distinct clusters of far-eastern and Siberian subtypes. There was also a minor difference in antigenicity between the Irkutsk isolates and other TBE virus strains, as demonstrated by the reactivity of monoclonal antibodies. Amino acid alignments of the E gene showed that the Irkutsk isolates had a single amino acid change at position 234 (Q or H); this amino acid position is considered to be a 'signature' of Siberian subtype TBE viruses. Strains isolated in Irkutsk also exhibited equivalent or somewhat higher virulence in mice compared with far-eastern TBE virus isolates. All viruses isolated in this study (i.e. far-east Asian and Siberian isolates) have 3' non-coding regions (NCRs) of almost the same length, which contrasts with the various sizes of 3'NCRs of other TBE viruses strains reported previously. The data presented in this study show that the 3'NCR is uniform among TBE viruses isolated from Siberia and far-eastern Asia and that the 3'NCR is essential for TBE virus growth in tick and/or rodent host cells.
  • Michael E. Murphy, Hiroaki Kariwa, Tetsuya Mizutani, Hiroki Tanabe, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima
    J Vet Med Sci. 社団法人日本獣医学会 63 (6) 637 - 645 0916-7250 2001/06 [Not refereed][Not invited]
     
    Mechanisms of anti-hantaviral activities of bovine lactoferrin (LF) and ribavirin (Rbv) were investigated. Hantavirus focus formation at 48 hr was 15% of the control in cells treated with 400μg/ml LF for 1 hr at 37℃ prior to viral infection. Post infection treatment with 100 μg/ml Rbv also inhibited the focus formation to 2.5% of the control. Combined LF pre- and Rbv post-infection treatment completely inhibited focus formation. Viral glycoprotein (G2) and nucleocapsid protein (NP) syntheses were delayed in LF pre-treated cells up to 24 hr post infection (hpi) but became comparable to the control by 48 hpi. Further, LF inhibited viral shedding at 24 hpi but did not inhibit shedding after 48 hpi. However, Rbv was able to inhibit synthesis of viral proteins, (+) and (-) stand RNAs also inhibited viral shedding after 24 hr. These results suggest that LF inhibits viral adsorption to cells, while Rbv inhibits viral RNA synthesis. For in vivo trials of LF and Rbv, LF pre- and Rbv post-treatment were evaluated in suckling mice infected with hantavirus, of which 7% survived. LF concentrations of 40 and 160 mg/kg administered prior to viral challenge improved survival rates to 15% and 70%, respectively for single administration and 85% and 94%, respectively, for double administration. Rbv concentrations of 25 and 50 mg/kg gave survival rates of 68% and 81%, respectively. This suggests that both LF and Rbv are efficacious in hantavirus infection in vivo.
  • ダニ媒介性脳炎(TBE)ウイルスシベリア型及び極東型の病原性の比較とワクチンの効果
    早坂 大輔, 後藤 明子, 好井 健太朗, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 131回 121 - 121 1347-8621 2001/03 [Refereed][Not invited]
  • ダニ媒介性脳炎ウイルス組み換え蛋白の作成と抗原性状の解析
    好井 健太朗, 早坂 大輔, 後藤 明子, 水谷 哲也, 苅和 宏明, 高島 郁夫
    日本獣医学会学術集会講演要旨集 (公社)日本獣医学会 131回 121 - 121 1347-8621 2001/03 [Refereed][Not invited]
  • Epidemiology of tick-borne encephalitis (TBE) and phylogenetic analysis of TBE viruses in Japan and Far Eastern Russia
    Ikuo Takashima, Daisuke Hayasaka, Akiko Goto, Hiroaki Kariwa, Tetsuya Mizutani
    Jpn J Infect Dis. 54 (1) 1 - 11 2001/01 [Not refereed][Not invited]
  • TAKASHIMA Ikuo, HAYASAKA Daisuke, KARIWA Hiroaki
    Journal of the Japan Veterinary Medical Association 日本獸医師会 53 (12) 793 - 799 0446-6454 2000/12/20
  • Michael E. Murphy, Hiroaki Kariwa, Tetsuya Mizutani, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima
    Arch. Virol. 145 (8) 1571 - 1582 2000/08 [Not refereed][Not invited]
  • Tetsuya Mizutani, Hisae Inagaki, Mitsuhiro Tada, Daisuke Hayasaka, Michael E. Murphy, Toshiyoshi Fujiwara, Jun-ichi Hamada, Hiroaki Kariwa, Ikuo Takashima
    Microbirol. Immunol. 44 (7) 597 - 603 2000/07 [Not refereed][Not invited]
  • Kimiyo Komoro, Daisuke Hayasaka, Tetsuya Mizutani, Hiroaki Kariwa, Ikuo Takashima
    Microbiol Immunol. Center for Academic Pub. Japan 44 (6) 533 - 536 0385-5600 2000/06 [Not refereed][Not invited]
  • Hiroaki Kariwa, Kumiko Yoshimatsu, Kouichi Araki, Chayama K, Kumada H, Michiko Ogino, Ebihara H, Michael E. Murphy, Tetsuya Mizutani, Ikuo Takashima, Jiro Arikawa
    Microbiol Immunol. Center for Academic Pub. Japan 44 (5) 357 - 362 0385-5600 2000/05 [Not refereed][Not invited]
  • Daisuke Hayasaka, Yoshiyuki Suzuki, Hiroaki Kariwa, Leonid Ivanov, Vladimir Volkov, Vladimir Demenev, Tetsuya Mizutani, Takashi Gojobori, Ikuo Takashima
    J. Gen. Virol. Society for General Microbiology 80 (Pt12) 3127 - 3135 0022-1317 1999/12 [Not refereed][Not invited]
     
    We have previously reported that tick-borne encephalitis (TBE) is endemic in a specific area of Hokkaido, Japan. In Oshima, the southern part of Hokkaido, TBE virus was isolated from sentinel dogs, ticks and rodents in 1995 and 1996. To identify when these TBE viruses emerged in Hokkaido, the times of divergence of TBE virus strains isolated in Oshima and far-eastern Russia were estimated. TBE virus was isolated in Khabarovsk in 1998 and the nucleotide sequences of viral envelope protein genes of isolates from Oshima and Khabarovsk were compared. From the synonymous substitution rate of these virus strains, the lineage divergence time of these TBE virus strains was predicted phylogenetically to be about 260–430 years ago. Furthermore, the virulence of TBE virus isolates from Oshima and Khabarovsk were compared in a mouse model. The results showed that the isolates possessed very similar virulence in mice. This report provides evidence that the Oshima strains of TBE virus in Hokkaido emerged from far-eastern Russia a few hundred years ago and this explains why these strains possess virulence similar to the TBE viruses isolated in Russia.
  • Tetsuya Mizutani, Hisae Inagaki, Daisuke Hayasaka, Hiroaki Kariwa, Ikuo Takashima
    Journal of Veterinary Medical Science 61 (7) 831 - 834 1782-155X 1999/07 [Refereed][Not invited]
     
    Transcription of Borna disease virus (BDV) in persistently infected MDCK (MDCK/BDV) cells increased in the fetal bovine serum free media as detected by Northern blot analysis. Especially, the amount of 1.9-kb RNA without cap formation at the 5' end and polyadenylation at the 3' end, increased as compared to other mRNA molecules of BDV. Growth arrest of MDCK/BDV cells observed in the condition of serum starvation might be important for increasing viral transcription. Since N-cadherin is the responsible factor for cell-to-cell contact, MDCK/BDV cells were cultured in calcium free medium which inhibits the interaction of N-cadherin. However, inhibition of cell-to-cell contact by N-cadherin is not effective on up regulation of viral transcription. Our finding in this study indicates that enhancement of BDV transcription by serum starvation is a useful technique for further investigation in understanding of mechanisms of BDV transcription.
  • Tetsuya Mizutani, Hisae Inagaki, Daisuke Hayasaka, Hiroaki Kariwa, Ikuo Takashima
    J. Vet. Med. Sci. 社団法人日本獣医学会 61 (7) 831 - 834 0916-7250 1999/07 [Not refereed][Not invited]
     
    Transcription of Borna disease virus (BDV) in persistently infected MDCK (MDCK/BDV) cells increased in the fatal bovine serum free media as detected by Northern blot analysis. Especially, the amount of 1.9-kb RNA without cap formation at the 5' end and polyadenylation at the 3' end, increased as compared to other mRNA molecules of BDV. Growth arrest of MDCK/BDV cells observed in the condition of serum starvation might be important for increasing viral transcription. Since N-cadherin is the responsible factor for cell to-cell contact, MDCK/BDV cells were cultured in calcium free medium which inhibits the interaction of N-cadherin. However, inhibition of cell-to-cell contact by N-cadlnerin is not effective on up regulation of viral transcription. Our finding in this study indicates that enhancement of BDV transcription by serum starvation is a useful technique for further investigation in understanding of mechanisms of BDV transcription.
  • 腎症候性出血熱
    苅和宏明, 水谷哲也, 高島郁夫
    「最新医学」 6月増刊号 54 1425 - 1431 1999/06 [Not refereed][Not invited]
  • Nobuyuki Chiba, Mihoro Osada, Kimiyo Komoro, Tetsuya Mizutani, Hiroaki Kariwa, Ikuo Takashima
    Vaccine 17 (11-12) 1532 - 1539 1999/03 [Not refereed][Not invited]
  • Koji Tsujimura, Tetsuya Mizutani, Hiroaki Kariwa, Kumiko Yoshimatsu, Michiko Ogino, Yuko Morii, Hisae Inagaki, Jiro Arikawa, Ikuo Takashima
    Journal of Veterinary Medical Science 61 (2) 113 - 117 1782-155X 1999/02 [Refereed][Not invited]
     
    For a serological diagnostic test for Borna disease (BD), we developed a capture ELISA with specificity and sensitivity based on detection of antibodies against BD virus (BDV) p40 protein. Using our capture ELISA system, the antibody response of rats inoculated intracerebrally with BDV at 4 weeks after birth showed a sharp increase from 1 to 4 weeks postinoculation (p.i.) and a steady level after 5 weeks p.i. To investigate prevalence of BDV infection among wild rats, we examined sera of Rattus norvegicus in Kami-iso town, Oshima district, Hokkaido, suggesting that rats in this area had not been infected by BDV.
  • T Mizutani, M Ogino, Y Nishino, T Kimura, H Inagaki, D Hayasaka, H Kariwa, Takashima, I
    JAPANESE JOURNAL OF VETERINARY RESEARCH 46 (4) 165 - 169 0047-1917 1999/02 [Refereed][Not invited]
     
    There are few copies of Borna disease virus (BDV) genome in peripheral blood mononuclear cells and no reliable standard reverse transcriptase-polymerase chain reaction (RT-PCR) method for the detection of BDV RNA, which is both highly sensitive and free of contamination. Single-step RT-PCR, in which both reverse transcription and amplification by Tag DNA polymerase work efficiently in a single buffer, was applied to detect the p24 region of BDV RNA in vitro and in vivo. Using in vitro synthesized RNA, it was demonstrated that at least 100 copies of BDV RNA could be detected and the sensitivity and specificity were nearly equal to those obtained by RT-nested PCR. We could detect BDV RNA from more than 1 pg of cellular RNA obtained from BDV-persistently infected MDCK cells. Furthermore, this method was successfully performed on brain specimens obtained from a BDV-infected rat at II weeks post-inoculation. This single-step RT-PCR method will be convenient for detecting limited amounts of BDV RNA in various cells and tissue samples.
  • Nobuyuki Chiba, Takuya Iwasaki, Tetsuya Mizutani, Hiroaki Kariwa, Takeshi Kurata, Ikuo Takashima
    Vaccine 17 (7-8) 779 - 787 1999/02 [Not refereed][Not invited]
  • Koji Tsujimura, Tetsuya Mizutani, Kumiko Yoshimatsu, Michiko Oginio, Yuko Morii, Hisae Inagaki, Jiro Arikawa, Hiroaki Kariwa, Ikuo Takashima
    J. Vet. Med. Sci. 社団法人日本獣医学会 61 (2) 113 - 117 0916-7250 1999/02 [Not refereed][Not invited]
     
    For a serological diagnostic test for Borna disease (BD), we developed a capture ELISA with specificity and sensitivity based on detection of antibodies against BD virus (BDV) p40 protein. Using our capture ELISA system, the antibody response of rats inoculated intracerebrally with BDV at 4 weeks after birth showed a sharp increase from 1 to 4 weeks postinoculation (p.i.) and a steady level after 5 weeks p.i. To investigate prevalence of BDV infection among wild rats, we examined sera of Rattus norvegicus in Kami-iso town, Oshima district, Hokkaido, suggesting that rats in this area had not been infected by BDV.
  • T Mizutani, H Inagaki, D Hayasaka, S Shuto, N Minakawa, A Matsuda, H Kariwa, Takashima, I
    ARCHIVES OF VIROLOGY 144 (10) 1937 - 1946 0304-8608 1999 [Refereed][Not invited]
     
    Regulation of viral RNA levels in infected cells is considered important in the investigation of viral transcription and replication. Amounts of Borna disease virus (BDV) RNAs were increased in confluent persistently BDV-infected MDCK cells (MDCK/BDV) cells, while maintained at low levels in growing cells. The amount of 1.9-kb RNA without cap formation and polyadenylation at the 5' and 3' ends respectively were remarkably increased (200% per day) in confluent MDCK/BDV cells. Both the full-length genomic and anti-genomic RNAs were increased accompained by 1.9-kb RNA, suggesting the transcription of the 1.9-kb RNA was important for replication of BDV. Ribavirin has an inhibitory effect on replication and transcription of BDV at concentrations from 1 to 10 mu g/ml [Mizutani T et al., Arch Virol (1998) 143: 2039-2044]. BDV transcripts were decreased with ribavirin treatment and increased after its removal which indicated that ribavirin has a reversible inhibitory effect on BDV transcription. Furthermore, BDV transcription was also decreased by two agents, RMNPA and EICAR, which selectively inhibit enzyme activity related to cap formation at the 5' end of mRNA. On the contrary, when the growing MDCK/BDV cells were treated with actinomycin D, transcripts of BDV RNA were increased for 24 h. These agents and culture conditions in this study were found to be useful tools for up-and down-regulation of BDV transcription in persistently BDV-infected cells.
  • Tetsuya Mizutani, Yoshii Nishino, Hiroaki Kariwa, Ikuo Takashima
    J. Vet. Med. Sci. 公益社団法人 日本獣医学会 61 (1) 77 - 80 0916-7250 1999/01 [Not refereed][Not invited]
     
    Several methods for the detection of Borna disease virus (BDV) RNA have been reported, one being the reverse transcription-nested polymerase chain reaction (RT-nested PCR) method. However, due to the possibility of contamination of the cloned DNA in a reaction tube, false-positive results might be obtained by RT-nested PCR. To detect only BDV RNA without anxiety of contamination, we developed an RT-nested PCR system using "mRNA selective PCR kit". Using this system, cDNA of BDV p40 in the plasmid (up to 5 × 107 molecules) was not amplified. BDV specific sequence was amplified from total RNA (more than 50 pg) of MDCK/BDV cells, which were persistently infected with BDV. These results indicate that this mRNA selective RT-nested PCR system can specifically amplify target RNA as distinguished from plasmid contaminated.
  • TAKASHIMA IKUO, ARIKAWA JIRO, KARIWA HIROAKI, NEURA TETSUYA
    北海道の研究開発 1998 95 - 100 1998/12 [Not refereed][Not invited]
  • Mizutani T, Ogino M, Nishino Y, Kimura T, Kariwa H, Tsujimura K, Inagaki H, Takashima I
    The Japanese journal of veterinary research 2-3 46 (2) 73 - 81 0047-1917 1998/11 [Refereed][Not invited]
     
    For detecting Borna disease virus (BDV) genomic stranded RNA, single-tube reverse transcription-polymerase chain reaction (St RT-PCR) was developed to equal the sensitivity of RT-nested PCR but with reduced risk of contamination. BDV-genomic stranded RNA was synthesized in vitro using plasmid cDNA of BDV p24 region as a template and RNA was also extracted from BDV-persistently infected MDCK (MDCK/BDV) cells. Both RNAs were amplified by St RT-PCR in which a single round of RT and a single round of PCR were performed in the same tube. Ten copies of synthesized RNA could be amplified by St RT-PCR, indicating that St RT-PCR method is as sensitive as the ordinary RT-nested PCR method. Furthermore, this method was applied to quantify the exact copy number of genomic RNA in MDCK/BDV cells. Signals were obtained from the samples containing more than 1 pg total cellular RNA. From the results, approximately 100 copies of BDV genomic RNA exist in one MDCK/BDV cell. BDV genomic RNA from the in vivo RNA samples using St RT-PCR, indicating this method is applicable for the epidemiological study of BDV without contamination.
  • Tetsuya Mizutani, Hisae Inagaki, Koichi Araki, Hiroaki Kariwa, Jiro Arikawa, Ikuo Takashima
    Arch. Virol. 143 (10) 2039 - 2044 1998/10 [Not refereed][Not invited]
  • M Morii, K Yoshimatsu, J Arikawa, GZ Zhou, H Kariwa, Takashima, I
    JOURNAL OF CLINICAL MICROBIOLOGY 36 (9) 2514 - 2521 0095-1137 1998/09 [Refereed][Not invited]
     
    Hantaan virus (HTN) and Seoul virus (SEO) are members of the genus Hantavirus in the family Bunyaviridae and are causative agents of hemorrhagic fever with renal syndrome. The complete and truncated nucleocapsid proteins (NP) of HTN and SEO were expressed by a recombinant baculovirus system, Antigenic characterization of the NP using monoclonal antibodies (Mabs)indicated that the binding sites For the serotype-specific MAbs were located between amino acids (aa) 155 and 429, a Western blot assay indicated that the serotype-specific epitopes were conformation dependent. An indirect immunofluorescence antibody (IFA) assay with the truncated NP (aa 155 to 429) was able to distinguish convalescent-phase sera from HTN and SEO patients. However, the antibody liters with the truncated NP were lower than those with the whole NP, The truncated NP of SEO (aa 155 to 429) could be used as an enzyme-linked immunosorbent assay (ELISA) antigen, but the truncated NP from HTN lost its reactivity when used for ELISA. The LFA assay using baculovirus-expressed truncated NP as an antigen is a rapid, simple, and safe test for distinguishing between HTN and SEO infections by serotype.
  • H Kariwa, M Fujiki, K Yoshimatsu, J Arikawa, Takashima, I, N Hashimoto
    ARCHIVES OF VIROLOGY 143 (2) 365 - 374 0304-8608 1998 [Refereed][Not invited]
     
    To understand the mode of transmission of Seoul type hantavirus in Wistar rats, we examined the shedding of the virus and antibody production in infected rats. When 1-day-old rats were inoculated with KI-83-262 strain of Seoul virus, the S segment of the viral genome was detected in lungs, clots, urine, saliva, submaxillary glands, rectums, and-kidneys by nested reverse transcriptase PCR. On the other hand, when 8-week-old rats were infected with the virus, viral genome was detected only in the lungs and rectum. In uninfected newborn rats intranasally administered urine from infected newborn rats, four of six rats shed the virus into their urine. In addition, three of eight rats kept in a same cage with infected animals also shed the virus into urine. Moreover, the virus genome was detected in the urine of urban rats (Rattus norvegicus) in an enzootic focus. These findings suggest that the urine containing virus from infected rats is an actual source of Seoul virus infection.
  • Takashima, I, H Kariwa, T Mizutani
    JAPANESE JOURNAL OF VETERINARY RESEARCH 45 (3) 176 - 177 0047-1917 1997/11 [Refereed][Not invited]
  • Takashima, I, M Hiyoshi, H Kariwa, R Mukaiya, N Hashimoto
    MICROBIOLOGY AND IMMUNOLOGY 40 (4) 265 - 270 0385-5600 1996 [Refereed][Not invited]
     
    Japanese quail were used for the infection model of avian chlamydiosis. One-day-old Japanese quail were highly susceptible to lethal infection by a Chlamydia psittaci strain of budgerigar origin upon inoculation via the air sac route with 10(4.1) FFU of the organism, showing an acute and lethal course with chlamydial propagation. In contrast, 7-day-old quail developed resistance to the infection as shown by the lack of lethal effect with the same dose. The resistance of 7-day-old birds was abolished by immunosuppressive treatment with cyclophosphamide. Upon inoculation with a sublethal dose of 10(2.1) FFU, latent infection was established in 1-day-old birds with a minimum number of the organism. The latent infection in the birds was converted to the lethal form by treatment with cyclophosphamide along with chlamydial propagation and suppression of antibody production.
  • Kariwa H, Kimura M, Yoshizumi S, Arikawa J, Yoshimatsu K, Takashima I, Hashimoto N
    Archives of virology 12 141 (12) 2327 - 2338 0304-8608 1996 [Refereed][Not invited]
  • Yoshimatsu K, Arikawa J, Yoshida R, Li H, Yoo YC, Kariwa H, Hashimoto N, Kakinuma M, Nobunaga T, Azuma I
    Laboratory animal science 6 45 641 - 646 0023-6764 1995/12 [Refereed][Not invited]
  • Kariwa H, Yoshizumi S, Arikawa J, Yoshimatsu K, Takahashi K, Takashima I, Hashimoto N
    The American journal of tropical medicine and hygiene 3 53 222 - 227 0002-9637 1995/09 [Refereed][Not invited]
  • Kariwa H, Kamimura M, Arikawa J, Yoshimatsu K, Takashima I, Hashimoto N
    Microbiology and immunology 1 39 (1) 35 - 41 0385-5600 1995 [Refereed][Not invited]
  • Kariwa H, Arikawa J, Takashima I, Isegawa Y, Yamanishi K, Hashimoto N
    Journal of virological methods 2 49 (2) 235 - 244 0166-0934 1994/09 [Refereed][Not invited]
  • Kariwa H, Isegawa Y, Arikawa J, Takashima I, Ueda S, Yamanishi K, Hashimoto N
    Virus research 1 33 (1) 27 - 38 0168-1702 1994/07 [Refereed][Not invited]
  • JG GARCIA, TAKASHIMA, I, H KARIWA, N HASHIMOTO
    JOURNAL OF VIROLOGICAL METHODS 48 (1) 31 - 41 0166-0934 1994/06 [Refereed][Not invited]
     
    A modified antibody-forming cell assay was used to enumerate splenocytes secreting antibodies to Japanese encephalitis (JE) virus and four other flaviviruses in infected cells as the target antigens. The optimal viral antigen expression for the assay was standardized in the infected cells for each virus and the incubation time varied depending of the cell line and the virus. The kinetics of response of JE virus-infected mice readily showed IgG isotype switching. Antibody-forming splenocytes of mice primed or boosted with one flavivirus could distinguish, in variable proportions, the homologous virus antigen from heterologous ones depending on the serocomplex of the virus. Antibody-forming cells from flavivirus-infected mice were flavivirus specific as evidenced by the lack of recognition of Getah virus (alphavirus) antigen. After JE virus-infected mice were cross-primed with another flavivirus, the IgG-forming cell response resembled the secondary response to both viruses but had higher affinity to JE virus than to the cross-priming virus.
  • Arikawa J, Ito M, Yao JS, Kariwa H, Takashima I, Hashimoto N
    The Journal of veterinary medical science / the Japanese Society of Veterinary Science 1 56 (1) 27 - 32 0916-7250 1994/02 [Refereed][Not invited]
     
    Epizootiological studies of hantavirus infection among urban rats were carried out through the surveys repeated 11 times at the same dumping ground area in 1983 to 1988. A total of 279 rats (Rattus norvegicus) were captured during the surveys. Sero-positive animals to hantavirus strain SR-11 were detected in all the surveys. Overall positive rate of rats 6 months old or more (94/128, 73.4%) was significantly higher than that of younger rats (23/151, 15.2%, x^2=96.4, P<0.001). Therefore, age dependent acquisition of hantavirus infection among rats was confirmed. Seven hantavirus strains, KI-83-262 (August, in 1983, designated as strain KI-262 in our previous report (2)), KI-85-1 and 85-2 (July in 1985), KI-88-4, 88-11, 88-15 and 88-24 (October, 1988) were isolated from lung tissues of adult rats which have high titers of neutralizing antibody. Although the serum specimens of virus carrier rats neutralized the infectivity of all the KI isolates, no apparent antigenic change in the isolates was detected by indirect immunofluorescent antibody (IFA) assay using polyclonal and monoclonal antibodies (MAbs) regardless of isolation years. However, neutralization test showed slight difference of antigenicity among KI strains. These results epizootiologically confirmed that hantavirus infected persistently among urban rats in a presence of neutralizing antibody.
  • Yoshimatsu K, Arikawa J, Kariwa H
    The Journal of veterinary medical science / the Japanese Society of Veterinary Science 6 55 (6) 1047 - 1050 0916-7250 1993/12 [Refereed][Not invited]
     
    Recombinant baculovirus-infected insect cells which expressed recombinant protein, analogous to the nucleocapsid protein (NP) of Seoul type hantavirus, strain SR-11 (rNP-SR-Sf9) were applied to the indirect immunofluorescent antibody (IFA) test. The rNP-SR-Sf9 reacted with anti NP MAb clones which recognized strain specific or hantavirus common epitopes in the IFA test. The recombinant antigen was detected by antibodies to 3 serotypes of hantaviruses (Hantaan 76-118, SR-11, Puumala). Antibody titers of a group of experimentally infected mouse and urban rat sera using rNP-SR-Sf9 and strain SR-11-infected Vero cell antigens were mutual correlative. These results indicated that the rNP-SR-Sf9 were an effective and safety substitute for Vero E6 cells in the IFA test for serosurveys of hantavirus infection.
  • J GARCIAGARCIA, TAKASHIMA, I, H KARIWA, N HASHIMOTO
    JOURNAL OF IMMUNOLOGICAL METHODS 157 (1-2) 259 - 267 0022-1759 1993/01 [Refereed][Not invited]
     
    A sensitive modified method for the detection in vitro of antibody-forming cells (AFCs) in Japanese encephalitis (JE) virus infected mice is described. The procedure involves the selection of the most appropriate incubation period, after the infection of monolayer cells, for expression of viral antigens to be recognized by AFCs. Adequate preservation of the expressed antigens was achieved after fixation with paraformaldehyde-lysine-periodate buffer (PLP). The development of spots which corresponded to AFCs was successfully obtained with the use of the avidin-biotin complex (ABC) amplification reaction. The number of the spots developing after completion of the assay was greater after PLP fixation compared with other fixation solutions such as methanol, formalin and acetone-water. Optimum antigen expression on the infected cells for recognition by lymphoid cells was reached after 24 h of infection. However, it was possible to detect viral antigens on the infected cells 8 h after infection. The ABC reaction was shown to be the best procedure for developing spots compared with other immunocytochemical methods. A linear increment was observed in the number of spots that developed at different spleen cell densities. This assay is simple to perform and could detect virus-specific Ig producing cells from the spleens of mice infected with JE virus. It also makes it possible to enumerate accurately the kinetics of the AFC response in different lymphoid organs during infection or after vaccination.
  • JS YAO, J ARIKAWA, H KARIWA, K YOSHIMATSU, TAKASHIMA, I, N HASHIMOTO
    JAPANESE JOURNAL OF VETERINARY RESEARCH 40 (2-3) 87 - 97 0047-1917 1992/09 [Refereed][Not invited]
     
    The effect of neutralizing monoclonal antibodies (N MAbs) on Hantaan virus infection of macrophages was investigated using P388D1 cells, a murine macrophage cell line. MAbs to the G1 protein (G1b) and the G2 protein (G2a and G2c) neutralized viral infectivity in P388D1 cells. N MAbs to G1b showed much higher neutralizing potency than those to G2a and G2c. With each N MAbs, two distinct effects were observed: neutralization of viral infectivity occurring at high concentrations and enhancement of that at low concentrations. Non-neutralizing MAbs, on the other hand, showed only enhancement of viral infectivity even at high concentrations without any inhibitory effects. The Fab fragments of N MAbs showed neither neutralizing nor enhancing activities. However, when the virus-Fab complexes were reacted with the anti-Fab antibodies, both neutralization and enhancement of viral infectivity were restored depending on the dose of Fab fragments. These results indicate that Hantaan virus infection of P388D1 cells is mediated by the Fc portion of the antibodies and neutralization is dependent on the concentration of N antibodies bound bivalently to the neutralization site on the virion.
  • H KARIWA, J ARIKAWA, TAKASHIMA, I, N HASHIMOTO
    JOURNAL OF VIROLOGICAL METHODS 37 (3) 345 - 354 0166-0934 1992/06 [Refereed][Not invited]
     
    A new serodiagnostic method designated protein-G antibody assay (PGA) was developed for detection of hantavirus infection in various species of animals. The assay procedure includes reacting the sera with hantavirus-infected cells on glass slides, followed by incubation of biotinylated protein G and amplification with the avidin-biotinylated peroxidase complex. Specific antibody in rabbit, rat, mouse and Mongolian gerbil serum was detected by this method. The PGA titres were similar to those of the neutralization titre. In the sera of Mongolian gerbils infected with strain SR-11, antibody was first detected 10 days post infection, and the titre increased to 1:256 at 18 days post-infection. PGA was evaluated using sera of urban rats (Rattus norvegicus) captured in an endemic area of hantavirus infection. The negative (less-than-or-equal-to 1:1, 24/62, 38.7%) and positive groups (greater-than-or-equal-to 1:16, 38/62, 61.3%) were clearly distinguished. PGA titres were closely related to IFA titres in the sera. Two of 10 sera from Clethrionomys rufocanus and one from Apodemus speciosus captured in the same endemic area were positive to both PGA and IFA. These data indicate that PGA is a simple and useful method for seroepizootiological surveys of hantavirus infection, especially in wild rodent reservoirs.
  • JS YAO, H KARIWA, TAKASHIMA, I, K YOSHIMATSU, J ARIKAWA, N HASHIMOTO
    ARCHIVES OF VIROLOGY 122 (1-2) 107 - 118 0304-8608 1992 [Refereed][Not invited]
     
    Antibody-dependent enhancement (ADE) of hantavirus infections (strains Hantaan 76-118 and SR-11) was studied using macrophage-like cell lines (J774.1, P388D 1, and U937). Significantly higher virus titers (1,000 to 4,000 FFU/ml) were obtained by pretreatment of the virus with immune serum as compared to normal serum (< 20 FFU/ml). Monoclonal antibodies (MAbs) to strain Hantaan 76-118 were employed to determine the antigenic determinants responsible for the ADE activity. ADE of the infection occurred with MAbs to both G1 and G2 envelope glycoproteins, but not with MAbs to nucleocapsid protein. Antigenic determinants related to haemagglutination or virus neutralization were found to cause ADE of the infection.
  • KARIWA HIROAKI, ARIKAWA JIRO, YO KENSHO, TAKASHIMA IKUO, HASHIMOTO NOBUO
    北海道獣医師会雑誌 35 (3) 69 - 74 0018-3385 1991/03 [Not refereed][Not invited]

MISC

  • 梶山実紗, 福田幸音, 佐々木道仁, THAMMAHAKIN Passawat, 前園佳祐, 長谷部理絵, 村上正晃, 村上正晃, 村上正晃, 村上正晃, 苅和宏明, 小林進太郎, 小林進太郎  日本獣医学会学術集会講演要旨集  166th-  2023
  • 梶山実紗, 福田幸音, 佐々木道仁, THAMMAHKIN Passawat, 前園佳祐, 長谷部理絵, 村上正晃, 村上正晃, 村上正晃, 村上正晃, 苅和宏明, 小林進太郎, 小林進太郎  日本ウイルス学会学術集会プログラム・予稿集(Web)  70th-  2023
  • 各分野で活躍する獣医師のさらなる飛躍に向けて 大学間連携による獣医学教育改善と獣医学生の就職動向
    苅和 宏明, 日本獣医師会獣医学術学会誌編集委員会  日本獣医師会雑誌  75-  (7)  290  -292  2022/07
  • 地球温暖化 地球規模で考える環境と健康
    岩田 敏, 有吉 紅也, 押谷 仁, 苅和 宏明, 橋爪 真弘  Modern Media  68-  (7)  283  -308  2022/07
  • 福田幸音, 高橋侑嗣, 佐々木道仁, 長谷部理絵, 村上正晃, 村上正晃, 村上正晃, 苅和宏明, 小林進太郎  日本ウイルス学会学術集会プログラム・予稿集(Web)  69th-  2022
  • 国内で分離されたダニ媒介性脳炎ウイルスの病原性の比較解析
    辻野 代, 好井 健太朗, 高橋 侑嗣, 苅和 宏明, 小林 進太郎  日本獣医学会学術集会講演要旨集  164回-  [FO  -2]  2021/09
  • 感染細胞内でmCherryをレポーターとして発現するウエストナイルウイルスの作製
    福田 幸音, 好井 健太郎, 苅和 宏明, 小林 進太郎  日本獣医学会学術集会講演要旨集  164回-  [FO  -3]  2021/09
  • ユビキチンの蓄積に着目したウエストナイルウイルスの脳炎病態の形成機構の解析
    武田 千咲, 川上 怜子, 好井 健太朗, 苅和 宏明, 小林 進太郎  日本獣医学会学術集会講演要旨集  164回-  [FO  -4]  2021/09
  • Hokkaidoウイルスの複製機構とオートファジーの関係性についての解析
    田宮 和真, 小林 進太郎, 苅和 宏明  日本獣医学会学術集会講演要旨集  164回-  [FO  -9]  2021/09
  • ウエストナイルウイルス感染によるタンパク質の核内輸送への影響
    小林 進太郎, 好井 健太朗, 澤 洋文, 苅和 宏明  日本獣医学会学術集会講演要旨集  164回-  [FO  -24]  2021/09
  • 小林進太郎, 好井健太朗, 松野啓太, 大場靖子, 澤洋文, 苅和宏明  日本分子生物学会年会プログラム・要旨集(Web)  44th-  2021
  • ウエストナイルウイルスのカプシドタンパク質とAMPKの相互作用の解析
    鈴木 健矢, 小林 進太郎, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  162回-  420  -420  2019/08  [Not refereed][Not invited]
  • 2017、2018年に北海道道央地域のヤマトマダニから分離されたダニ媒介性脳炎ウイルスの性状解析
    高橋 侑嗣, 小林 進太郎, 石塚 万里子, 中尾 亮, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  162回-  421  -421  2019/08  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルス由来非コードRNAと相互作用するマダニ宿主蛋白質の同定及び機能解析
    西山 祥子, 平野 港, 武藤 芽未, 小林 進太郎, 神谷 亘, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  162回-  421  -421  2019/08  [Not refereed][Not invited]
  • エンベロープタンパク質のアミノ酸変異によるウエストナイルウイルスの増殖および病態形成への影響
    小林 進太郎, 金子 知里, 川上 怜子, 長谷部 理絵, 澤 洋文, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  162回-  431  -431  2019/08  [Not refereed][Not invited]
  • 小林進太郎, 金子知里, 川上怜子, 長谷部理絵, 澤洋文, 好井健太朗, 苅和宏明  日本ウイルス学会学術集会プログラム・予稿集(Web)  67th-  2019
  • 小林進太郎, 好井健太朗, PHONGPAEW Wallaya, 武藤芽未, 平野港, 大場靖子, 澤洋文, 苅和宏明  日本分子生物学会年会プログラム・要旨集(Web)  42nd-  2019
  • 中釜尚人, 平野港, 武藤芽未, 西山祥子, 中尾亮, 小林進太郎, 苅和宏明, 好井健太朗  日本獣医学会学術集会講演要旨集  161st-  383  2018/08/21  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのウイルス様粒子を用いた新規IgM-ELISA系の開発
    中安 美樹, 小林 進太郎, 平野 港, 武藤 芽未, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  161回-  384  -384  2018/08  [Not refereed][Not invited]
  • 2017年に北海道道央地域で分離されたダニ媒介性脳炎ウイルスの性状解析
    高橋 侑嗣, 石塚 万里子, 平野 港, 武藤 芽未, 西山 祥子, 小林 進太郎, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  161回-  384  -384  2018/08  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルス由来非コードRNAの感染時における機能解析
    西山 祥子, 平野 港, 武藤 芽未, 神原 真生, 小林 進太郎, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  161回-  384  -384  2018/08  [Not refereed][Not invited]
  • ユビキチンの蓄積に着目したウエストナイルウイルスの病原性解析
    川上 怜子, 小林 進太郎, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  161回-  384  -384  2018/08  [Not refereed][Not invited]
  • Hokkaidoウイルスのエンベロープ糖タンパク質Gnの組換えタンパク質発現とその応用
    岡崎 はるか, 小林 進太郎, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  161回-  385  -385  2018/08  [Not refereed][Not invited]
  • 北海道のアライグマを対象としたダニ媒介性脳炎ウイルスの血清疫学調査
    佐鹿 万里子, 石塚 万里子, 三瓶 孝男, 小林 進太郎, 西山 祥子, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  161回-  394  -394  2018/08  [Not refereed][Not invited]
  • 北海道と福島県の野生動物におけるダニ媒介性脳炎ウイルス(TBEV)の血清学的調査(A serological survey for tick-borne encephalitis virus(TBEV) in wild animals in Hokkaido and Fukushima prefecture)
    Dulamjav Jamsransuren, 小川 晴子, 佐々木 基樹, 福本 晋也, 松本 高太郎, 好井 健太朗, 苅和 宏明, 浅川 満彦, 奥田 圭, 山口 英美  日本獣医学会学術集会講演要旨集  161回-  395  -395  2018/08  [Not refereed][Not invited]
  • ウエストナイルウイルス感染で起こるオートファジーの抑制と神経病態形成の関係
    小林 進太郎, 好井 健太朗, Wallaya Phongpaew, 武藤 芽未, 平野 港, 大場 靖子, 澤 洋文, 苅和 宏明  日本獣医学会学術集会講演要旨集  161回-  395  -395  2018/08  [Not refereed][Not invited]
  • ウエストナイルウイルスのカプシドタンパク質によるオートファジーの抑制による変性タンパク質の蓄積と神経病態形成についての解析
    小林 進太郎, 好井 健太朗, Phonqphaew Wallaya, 武藤 芽未, 平野 港, 大場 靖子, 澤 洋文, 苅和 宏明  生命科学系学会合同年次大会  2017年度-  [3P  -1110]  2017/12  [Not refereed][Not invited]
  • ウエストナイルウイルスの脳内侵入におけるエンベロープタンパク質のアミノ酸の解析
    金子 知里, 小林 進太郎, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  160回-  411  -411  2017/08  [Not refereed][Not invited]
  • ダニ媒介性ウイルス感染におけるダニRNAi関連因子の機能解析
    神原 真生, 平野 港, 武藤 芽未, 石塚 万里子, 小林 進太郎, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  160回-  411  -411  2017/08  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスの3'非翻訳領域に関わる宿主因子の検索
    武藤 芽未, 神谷 亘, 境 瑞紀, 平野 港, 小林 進太郎, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  160回-  411  -411  2017/08  [Not refereed][Not invited]
  • Hokkaidoウイルスと他のハンタウイルスの共感染による増殖性の補完に関する研究
    梶河 紗代, 岩崎 里奈, 真田 崇弘, 小林 進太郎, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  159回-  408  -408  2016/08  [Not refereed][Not invited]
  • フラビウイルスゲノムの神経細胞内輸送機構の解析
    平野 港, 境 瑞紀, 武藤 芽未, 小林 進太郎, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  159回-  409  -409  2016/08  [Not refereed][Not invited]
  • ウエストナイルウイルスの粒子放出過程におけるRab8bタンパク質の役割
    小林 進太郎, 鈴木 忠樹, 川口 晶, Phongphaew Wallaya, 好井 健太朗, 苅和 宏明, 大場 靖子, 澤 洋文  日本獣医学会学術集会講演要旨集  159回-  409  -409  2016/08  [Not refereed][Not invited]
  • In trans補完系によるダニ媒介性脳炎ウイルスのゲノム複製機構の解析
    山内 沙也果, 小林 進太郎, 平野 港, 武藤 芽未, 石塚 万里子, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  159回-  409  -409  2016/08  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのNucleoside Inhibitor耐性変異の解析
    近藤 寛史, 平野 港, 石塚 万里子, 武藤 芽未, 小林 進太郎, 苅和 宏明, Daniel Ruzek, 好井 健太朗  日本獣医学会学術集会講演要旨集  159回-  423  -423  2016/08  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスの神経細胞内におけるウイルスゲノムRNA輸送機構の解析
    平野 港, 境 瑞紀, 苅和 宏明, 小林 進太郎, 好井 健太朗  日本生化学会大会・日本分子生物学会年会合同大会講演要旨集  88回・38回-  [1P1134]  -[1P1134]  2015/12  [Not refereed][Not invited]
  • ウエストナイルウイルス感染による変性タンパク質蓄積機構の解析
    小林 進太郎, Phongphaew Wallaya, 好井 健太朗, 平野 港, 武藤 芽未, 大場 靖子, 澤 洋文, 苅和 宏明  日本生化学会大会・日本分子生物学会年会合同大会講演要旨集  88回・38回-  [1P1135]  -[1P1135]  2015/12  [Not refereed][Not invited]
  • ダニ媒介性脳炎ウイルスのウイルス様粒子を用いた動物種非特異的な新規血清学的診断法の開発
    稲垣 恵理, 境 瑞紀, 平野 港, 武藤 芽未, 苅和 宏明, 好井 健太朗  日本獣医学会学術集会講演要旨集  158回-  365  -365  2015/08  [Not refereed][Not invited]
  • イムノクロマトグラフィー法によるハンタウイルスの迅速診断法の開発
    小山 芽以, 吉松 組子, 好井 健太朗, 有川 二郎, 苅和 宏明  日本獣医学会学術集会講演要旨集  158回-  373  -373  2015/08  [Not refereed][Not invited]
  • 中尾亮, 梶原将大, 邱永晋, 森亜紀奈, 直亨則, 村松美笑子, 好井健太朗, 苅和宏明, 澤洋文, 杉本千尋, 高田礼人  日本獣医学会学術集会講演要旨集  157th-  451  2014/08/11  [Not refereed][Not invited]
  • モンゴルにおけるダニ媒介性脳炎ウイルスの分離と性状解析
    武藤 芽未, Bazartseren Boldbaatar, 好井 健太朗, 苅和 宏明  日本獣医学会学術集会講演要旨集  157回-  439  -439  2014/08  [Not refereed][Not invited]
  • レポーター遺伝子発現ダニ媒介性脳炎ウイルスの作製と性状解析
    池端 真帆, 好井 健太朗, 境 瑞紀, 平野 港, 苅和 宏明  日本獣医学会学術集会講演要旨集  157回-  450  -450  2014/08  [Not refereed][Not invited]
  • 苅和宏明, 好井健太朗, 高島郁夫  日本臨床  618  -621  2013/12/20  [Not refereed][Not invited]
  • Hiroaki Kariwa, Ryo Murata, Masashi Totani, Kentaro Yoshii, Ikuo Takashima  INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH  10-  (12)  7144  -7164  2013/12  [Not refereed][Not invited]
     
    In this review, we discuss the possibility that the glycosylation of West Nile (WN) virus E-protein may be associated with enhanced pathogenicity and higher replication of WN virus. The results indicate that E-protein glycosylation allows the virus to multiply in a heat-stable manner and therefore, has a critical role in enhanced viremic levels and virulence of WN virus in young-chick infection model. The effect of the glycosylation of the E protein on the pathogenicity of WN virus in young chicks was further investigated. The results indicate that glycosylation of the WN virus E protein is important for viral multiplication in peripheral organs and that it is associated with the strong pathogenicity of WN virus in birds. The micro-focus reduction neutralization test (FRNT) in which a large number of serum samples can be handled at once with a small volume (15 L) of serum was useful for differential diagnosis between Japanese encephalitis and WN virus infections in infected chicks. Serological investigation was performed among wild birds in the Far Eastern region of Russia using the FRNT. Antibodies specific to WN virus were detected in 21 samples of resident and migratory birds out of 145 wild bird samples in the region.
  • 好井健太朗, 寸田祐嗣, 五十嵐学, 横澤香菜, 境瑞紀, 苅和宏明, HOLBROOK Michael  日本ウイルス学会学術集会プログラム・抄録集  61st-  233  2013/10/29  [Not refereed][Not invited]
  • 好井健太朗, 寸田祐嗣, 五十嵐学, 横澤香菜, 境瑞紀, 苅和宏明, HOLBROOK Michael, 高島郁夫  日本獣医学会学術集会講演要旨集  156th-  303  -303  2013/08/30  [Not refereed][Not invited]
  • 苅和 宏明, 尾崎 由佳, 真田 崇弘, 池中 良徳, 石塚 真由美, 坪田 敏男, 好井 健太朗, 吉松 組子, 有川 二郎, 高島 郁夫  獣医畜産新報  66-  (4)  262  -264  2013/04  [Not refereed][Not invited]
     
    ハンタウイルスはげっ歯類媒介性の人獣共通感染症の病原体で、腎症候性出血熱(HFRS)またはハンタウイルス肺症候群(HPS)を引き起こす。近年の日本におけるげっ歯類のハンタウイルス感染状況を明らかにするために、1994年から2010年にかけて国内の様々な地域で捕獲された1658匹のげっ歯類の血清について、抗ハンタウイルス抗体の検出を行った。840例のRattus属げっ歯類(ドブネズミとクマネズミ)は全て抗体陰性であった。北海道以外の地域で捕獲された野生げっ歯類113例はいずれも抗体陰性であったのに対し、北海道で捕獲された705例の野性げっ歯類のうち、エゾヤチネズミの7.4%(26/352)とアカネズミの1.2%(2/168)が抗体を保有していた。(著者抄録)
  • 牧雅大, 真田崇弘, 瀬戸隆弘, 永田典代, 好井健太郎, 苅和宏明  日本獣医学会学術集会講演要旨集  156th-  2013
  • 牧雅大, 真田崇弘, 瀬戸隆弘, 永田典代, 好井健太朗, 苅和宏明  日本ウイルス学会学術集会プログラム・抄録集  61st-  2013
  • 駒 貴明, 吉松 組子, 垂石 みどり, 宮下 大輔, 遠藤 理香, 清水 健太, 安田 俊平, 天田 貴子, 瀬戸 隆弘, 村田 亮, 吉田 喜香, 苅和 宏明, 高島 郁夫, 有川 二郎  北海道醫學雜誌 = Acta medica Hokkaidonensia  88-  (1)  35  -35  2013/01/01  [Not refereed][Not invited]
  • 中尾桃子, 真田崇弘, 佐々木宣哉, サーサ ンゴンダ, 好井健太朗, 亀山武志, 高岡晃教, 苅和宏明  日本ウイルス学会学術集会プログラム・抄録集  60th-  429  2012/10/31  [Not refereed][Not invited]
  • 中尾桃子, 真田崇弘, 佐々木宣哉, SAASA Ngonda, 好井健太朗, 亀山武志, 高岡晃教, 苅和宏明  日本獣医学会学術集会講演要旨集  154th-  265  2012/08/31  [Not refereed][Not invited]
  • Hiroaki Kariwa, Haruka Yoshida, Cornelio Sanchez-Hernandez, Maria de Lourdes Romero-Almaraz, Jose Alberto Almazan-Catalan, Celso Ramos, Daisuke Miyashita, Takahiro Seto, Ayako Takano, Masashi Totani, Ryo Murata, Ngonda Saasa, Mariko Ishizuka, Takahiro Sanada, Kentaro Yoshii, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima  VIRUS RESEARCH  163-  (2)  486  -494  2012/02  [Not refereed][Not invited]
     
    A variety of hantaviruses are harbored by rodents in North and South America, some of which can cause hantavirus pulmonary syndrome. To obtain greater evolutionary insight into hantaviruses in the Americas, a total of 211 rodents were captured in the Mexican states of Guerrero and Morelos in 2006. Anti-hantavirus antibodies were detected in 27 of 211 serum samples (12.8%) by ELISA. The distribution of seropositive rodents was: 17 Peromyscus beatae, 1 Megadontomys thomasi,1 Neotoma picta, 6 Reithrodontomys sumichrasti, and 2 Reithrodontomys megalotis. The hantavirus small (S), medium (M), and large (L) genome segments from P. beatae, R. sumichrasti, and R. megalotis were amplified and the sequences covering the open reading frames were determined. The hantaviruses from P. beatae, R. sumichrasti, and R. megalotis were provisionally designated Montano (MTN), Carrizal (CAR), and Huitzilac (HUI), respectively. The M segment amino acid identities among the Mexican hantaviruses were 80.8-93.0%. When these M segments were compared to those of known hantaviruses, MTN virus was most closely related to Limestone Canyon (LSC) virus (88.9% amino acid identity), while the CAR and HUI viruses were most closely related to El Moro Canyon (ELMC) virus (90-91% identity). Phylogenetic analysis revealed that the MTN, CAR, and HUI viruses occupy a monophyletic clade with the LSC, ELMC, and Rio Segundo viruses, which are harbored by Peromyscus boylii, R. megalotis, and Reithrodontomys mexicanus, respectively. The data obtained in this study provide important information for understanding the evolution of hantaviruses in the Americas. (C) 2011 Elsevier B.V. All rights reserved.
  • 真田崇弘, 瀬戸隆弘, 尾崎由佳, NGONDA Saasa, 吉松組子, 有川二郎, 好井健太朗, 苅和宏明  日本ウイルス学会北海道支部夏季シンポジウム講演抄録  46th-  2012
  • Takahiro Seto, Noriyo Nagata, Keisuke Yoshikawa, Osamu Ichii, Takahiro Sanada, Ngonda Saasa, Yuka Ozaki, Yasunori Kon, Kentaro Yoshii, Ikuo Takashima, Hiroaki Kariwa  VIRUS RESEARCH  163-  (1)  284  -290  2012/01  [Not refereed][Not invited]
     
    Hantaan virus (HTNV) is a causative agent of hemorrhagic fever with renal syndrome (HFRS). The pathogenesis of HFRS has not been fully elucidated, mainly due to the lack of a suitable animal model. In laboratory mice, HTNV causes encephalitis. However, that symptom is dissimilar to human hantavirus infections. We found that HTNV strain AA57 (isolated from Apodemus agrarius in Far East Russia) caused pulmonary disease in 2-week-old ICR mice. The clinical signs of the infected mice were piloerection, trembling, hunching, labored breathing, and body-weight loss. A large volume of pleural effusion was collected from thoracic cavities of the dead mice. Overall, 45% of the mice inoculated with 3000 focus forming units (FFU) of the virus began to show clinical symptoms at 8 days post-inoculation, and 25% of the inoculated mice died within 3 days of onset of the disease. The morbidity and mortality rates of the mice inoculated with 30-30,000 FFU of HTNV strain AA57 were roughly equivalent. The highest rates of virus positivity (11/12) and the highest titers of HTNV strain AA57 were detected in the lungs of the dead mice, while lower detection rates and viral titers were found in the heart, kidneys, spleen, and brain. Interstitial pneumonia, perivascular edema, hemorrhage, inflammatory infiltration and vascular failure were observed in the lungs of the sick mice. Hantaviral antigens were detected in the lung endothelial cells of the sick mice. The symptoms and pathology of this mouse model resemble those of hantavirus pulmonary syndrome (HPS) and, to a certain extent, those of HFRS. This is the first report that, in laboratory mice, the HFRS-related hantavirus causes a HPS-like disease and shares some symptom similarities with HFRS. (C) 2011 Elsevier B.V. All rights reserved.
  • Kentaro Yoshii, Manabu Igarashi, Osamu Ichii, Kana Yokozawa, Kimihito Ito, Hiroaki Kariwa, Ikuo Takashima  JOURNAL OF GENERAL VIROLOGY  93-  (1)  27  -38  2012/01  [Not refereed][Not invited]
     
    Flaviviruses are assembled to bud into the lumen of the endoplasmic reticulum (ER) and are secreted through the vesicle transport pathway, but the details of the molecular mechanism of virion assembly remain largely unknown. In this study, a highly conserved region in the prM protein was identified among flaviviruses. In the subviral particle (SP) system of tick-borne encephalitis virus (TBEV) and Japanese encephalitis virus, secretion of SPs was impaired by a mutation in the conserved region in the prM protein. Viral proteins were sparse in the Golgi complex and accumulated in the ER. Ultrastructural analysis revealed that long filamentous structures, rather than spherical SPs, were observed in the lumen of the ER as a result of the mutation. The production of infectious virions derived from infectious cDNA of TBEV was also reduced by mutations in the conserved region. Molecular modelling analysis suggested that the conserved region is important for the association of prM-envelope protein heterodimers in the formation of a spike of immature virion. These results are the first demonstration that the conserved region in the prM protein is a molecular determinant for the flavivirus assembly process.
  • Masashi Totani, Kentaro Yoshii, Hiroaki Kariwa, Ikuo Takashima  AVIAN DISEASES  55-  (4)  561  -568  2011/12  [Not refereed][Not invited]
     
    Birds are important for the transmission of West Nile virus (WNV) in nature, but the significance of the potential N-linked glycosylation at position 154 in the WNV envelope (E) protein with regard to viral replication in young chickens has not been assessed. In this study, the effect of glycosylation of the WNV E protein on viral pathogenicity in birds was investigated using young domestic chicks. A higher viral load was detected in the blood and the peripheral organs, particularly the hearts, of 2-day-old chicks inoculated with a glycosylated WNV variant compared to those inoculated with the nonglycosylated variant. There was no significant difference in the neutralizing antibody titers and cytokine expression profiles in chickens inoculated with the glycosylated and the nonglycosylated WNV variants. In contrast, no virus was detected in the blood and the tissues of 3-wk-old chicks, although the host immune response was induced to similar levels as in the 2-day-old chicks. These data indicate the utility of young domestic chicks as an animal model of WNV infection; they also indicate that glycosylation of the E protein of WNV enhances multiplication in the blood and peripheral organs, which is associated with the strong pathogenicity of WNV in birds.
  • Yuki Omori-Urabe, Kentaro Yoshii, Ayae Ikawa-Yoshida, Hiroaki Kariwa, Ikuo Takashima  MICROBIOLOGY AND IMMUNOLOGY  55-  (12)  893  -897  2011/12  [Not refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) causes severe encephalitis in humans. It is endemic in one area of Japan; however no commercial vaccine is available in that country. In this Japan-based study, the efficacy of subviral particles (SPs) of TBEV administered by needle-free injector was evaluated as a vaccine candidate. Inoculation with SP-encoding DNA by needle-free injector induced neutralizing antibodies more efficiently than when administered by needle and syringe, and mice vaccinated with one dose by needle-free injector survived challenge with a lethal dose of TBEV. These results suggest that SP vaccines delivered by needle-free injector can protect against TBEV infection.
  • Ayako Takano, Kentaro Yoshii, Yuki Omori-Urabe, Kana Yokozawa, Hiroaki Kariwa, Ikuo Takashima  ARCHIVES OF VIROLOGY  156-  (11)  1931  -1941  2011/11  [Not refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) causes severe encephalitis in humans. The Sofjin-HO strain is the prototype strain of the TBEV Far-Eastern subtype and is highly pathogenic in a mouse model. In this study, we constructed replicons and infectious cDNA clones of the Sofjin-HO strain. The replication of the replicon RNA was confirmed, and infectious viruses were recovered from the infectious cDNA clone. The recombinant viruses showed similar virulence characteristics to those of the parental virus. While characterizing the replicon and infectious cDNA, several amino acid differences derived from cell culture adaptations were analysed. The amino acids differences at E position 496 and NS4A position 58 were found to affect viral replication. The Gly- or Ala-to-Glu substitution at E position 122 was shown to increase neuroinvasiveness in mice. These replicons and infectious cDNA clones are useful in revealing the viral molecular determinants involved in the replication and pathogenicity of TBEV.
  • Takahiro Sanada, Hiroaki Kariwa, Noriyo Nagata, Yoichi Tanikawa, Takahiro Seto, Kumiko Yoshimatsu, Jiro Arikawa, Kentaro Yoshii, Ikuo Takashima  VIRUS RESEARCH  160-  (1-2)  108  -119  2011/09  [Not refereed][Not invited]
     
    The mechanism of hantavirus persistent infection in natural hosts is poorly understood due to a lack of laboratory animal models. Herein, we report that Syrian hamsters (Mesocricetus auratus) infected with Puumala virus (PUUV) at 4 weeks old show persistent infection without clinical symptoms for more than 2 months. IgG and IgM antibodies against the viral nucleocapsid protein and neutralizing antibody were first detectable at 14 days postinoculation (dpi) and maintained through 70 dpi. Viral RNA was first detected from 3 dpi in lungs and blood clots, and was detected in all tissues tested at 7 dpi. The viral RNA persisted for at least 70 days in the lungs, kidney, spleen, heart, and brain. The highest level of RNA copies was observed at 14 dpi in the lungs. Slight inflammatory reactions were observed in the lungs, adrenal glands, and brain. Immunohistochemical analysis revealed that PUUV antigen persisted until 56 dpi in the kidneys and adrenal glands. Infected hamsters showed no body weight loss or clinical signs. These results indicate that PUUV infection in hamsters is quite similar to the hantavirus infection of natural host rodents. (C) 2011 Elsevier B.V. All rights reserved.
  • 尾崎由佳, 萩谷友洋, 真田崇弘, 瀬戸隆弘, TAYLOR Kyle, 吉川佳佑, IVANOV Leonid, 好井健太朗, 坪田敏男, 池中良徳, 石塚真由美, 吉松組子, 有川二郎, 苅和宏明  日本獣医学会学術集会講演要旨集  152nd-  256  -256  2011/08/31  [Not refereed][Not invited]
  • 尾崎由佳, 萩谷友洋, 真田崇弘, 瀬戸隆弘, TAYLOR Kyle, 吉川佳佑, IVANOV Leonid I, 好井健太朗, 坪田敏男, 池中良徳, 石塚真由美, 吉松組子, 有川二郎, 苅和宏明  北海道獣医師会雑誌  55-  (8)  415  -415  2011/08/10  [Not refereed][Not invited]
  • Mayumi Obara, Takeo Yamauchi, Mamoru Watanabe, Sumiyo Hasegawa, Yasufumi Ueda, Kentaro Matsuno, Masae Iwai, Eiji Horimoto, Takeshi Kurata, Takenori Takizawa, Hiroaki Kariwa, Ikuo Takashima  AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE  84-  (5)  695  -708  2011/05  [Not refereed][Not invited]
     
    To determine the mechanisms of maintenance and evolution of Japanese encephalitis virus (JEV) in a temperate zone, we attempted to isolate JEV from mosquitoes and pigs in Toyama Prefecture, Japan. A total of 87 JEVs were isolated from female Culex tritaeniorhynchus mosquitoes and pigs during 2005-2009. The prevalence of JEV in Toyama Prefecture was seasonally late in comparison with that of the virus during 1966-1972. Furthermore, JEVs were isolated after the peak in the number of female Cx. tritaeniorhynchus. Among JEV strains isolated in this study, two distinct groups were observed within genotype I of the phylogeny generated from nucleotide sequence information derived from the envelope and capsid/premembrane genes: strains belonging to the major type were isolated during 2005-2009, and strains from the minor type were isolated only in 2007. The major type has exhibited gradual change in its envelope and capsid/premembrane genes, and all isolates obtained in 2008 and 2009 had a novel deletion of seven nucleotides in the variable region of the 3'-untranslated region.
  • Takahiro Seto, Evgeniy A. Tkachenko, Vyacheslav G. Morozov, Yoichi Tanikawa, Sergey I. Kolominov, Sergey N. Belov, Ichiro Nakamura, Nobuo Hashimoto, Yasuhiro Kon, Alexander E. Balakiev, Tamara K. Dzagurnova, Olga A. Medvedkina, Mina Nakauchi, Mariko Ishizuka, Kentaro Yoshii, Kumiko Yoshimatsu, Leonid V. Ivanov, Jiro Arikawa, Ikuo Takashima, Hiroaki Kariwa  JOURNAL OF VIROLOGICAL METHODS  173-  (1)  17  -23  2011/04  [Not refereed][Not invited]
     
    Puumala virus (PUUV) and other Arvicolinae-borne hantaviruses are difficult to cultivate in cell culture. To isolate these hantaviruses efficiently, hantavirus nucleocapsid protein (NP)-positive but seronegative wild rodents were selected by NP-detection ELISA. Three of 68 Myodes glareolus captured in Samara, Russia, were NP-positive and seronegative. Syrian hamsters were inoculated with lung homogenates from NP-positive rodents for virus propagation. Virus isolation in vitro was carried out by inoculation of lung homogenates of NP-positive hamsters to Vero E6 cell monolayers. Two PUUV strains (Samara49/CG/2005 and Samara94/CG/2005) from M. glareolus were isolated in Vero E6 cells. Nucleotide and amino acid sequence identities of the S segment of these isolates to those of PUUV F-s808 from a fatal HFRS patient in Samara region were 96.7-99.3% and 99.3-100.0%, respectively. Morphologic features of Vero E6 cells infected with PUUV strain Samara49/CG/2005 were quite similar to those of Hantaan virus-infected cells. Isolation of Hokkaido virus from Myodes rufocanus captured in Hokkaido, Japan, was also performed. Hokkaido virus NP and RNA were recovered and maintained in hamsters. These results suggest that inoculation of Syrian hamsters with rodent samples is an efficient method for the isolation and maintenance of PUUV and other Arvicolinae-borne hantaviruses. (C) 2011 Elsevier B.V. All rights reserved.
  • 瀬戸隆弘, 吉川佳佑, 真田崇弘, SAASA Ngonda, 尾崎由佳, 市居修, 好井健太朗, 昆泰寛, 苅和宏明  日本獣医学会学術集会講演要旨集  151st-  245  -245  2011/03/01  [Not refereed][Not invited]
  • Ryo Murata, Kazuaki Hashiguchi, Kentaro Yoshii, Hiroaki Kariwa, Kensuke Nakajima, Leonid I. Ivanov, Galina N. Leonova, Ikuo Takashima  AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE  84-  (3)  461  -465  2011/03  [Not refereed][Not invited]
     
    West Nile (WN) virus has been spreading geographically to non-endemic areas in various parts of the world. However, little is known about the extent of WN virus infection in Russia. Japanese encephalitis (JE) virus, which is closely related to WN virus, is prevalent throughout East Asia. We evaluated the effectiveness of a focus reduction neutralization test in young chicks inoculated with JE and WN viruses, and conducted a survey of WN infection among wild birds in Far Eastern Russia. Following single virus infection, only neutralizing antibodies specific to the homologous virus were detected in chicks. The neutralization test was then applied to serum samples from 145 wild birds for WN and JE virus, Twenty-one samples were positive for neutralizing antibodies to WN. These results suggest that WN virus is prevalent among wild birds in the Far Eastern region of Russia.
  • Kentaro Yoshii, Keita Mottate, Yuki Omori-Urabe, Yumiko Chiba, Takahiro Seto, Takahiro Sanada, Junko Maeda, Mayumi Obara, Shuji Ando, Naoto Ito, Makoto Sugiyama, Hiroshi Sato, Hiroshi Fukushima, Hiroaki Kariwa, Ikuo Takashima  JOURNAL OF VETERINARY MEDICAL SCIENCE  73-  (3)  409  -412  2011/03  [Not refereed][Not invited]
     
    Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis in humans. Rodent species that are potential hosts for TBEV are widely distributed in various regions in Japan. In this study, we carried out large-scale epizootiological surveys in rodents from various areas of Japan. A total of 931 rodent and insectivore sera were collected from field surveys. Rodents seropositive for TBEV were found in Shimane Prefecture in Honshu and in several areas of Hokkaido Prefecture. These results emphasize the need for further epizootiological and epidemiological research of TBEV and preventive measures for emerging tick-borne encephalitis in Japan.
  • Ayae Ikawa-Yoshida, Kentaro Yoshii, Kazue Kuwahara, Mayumi Obara, Hiroaki Kariwa, Ikuo Takashima  MICROBIOLOGY AND IMMUNOLOGY  55-  (2)  100  -107  2011/02  [Not refereed][Not invited]
     
    Tick-borne encephalitis (TBE) virus causes severe encephalitis with serious sequelae in humans. An epizootiological survey of wild rodents is effective to detect TBE virus-endemic areas; however, limited serological diagnostic methods are available to detect anti-TBE virus antibodies in wild rodents. In this study, ELISAs for the detection of rodent antibodies against the TBE virus were developed using two recombinant proteins, domain III of the E protein (EdIII) and subviral particles (SPs), as the antigens. As compared with the neutralization test, the ELISA using EdIII had 77.1% sensitivity and 80.0% specificity, and the ELISA using SPs had 91.4% sensitivity and 100% specificity. Furthermore, when the ELISAs were applied to the epizootiological survey in the TBE virus-endemic area, both of the ELISAs was able to detect wild rodents with TBE virus-specific antibodies. This is the first study to show that ELISAs using recombinant antigens can be safe and useful in the detection of TBE virus-infected wild rodents in epizootiological research.
  • Kentaro Yoshii, Manabu Igarashi, Kimihito Ito, Hiroaki Kariwa, Michael R. Holbrook, Ikuo Takashima  VIRUS RESEARCH  155-  (1)  61  -68  2011/01  [Not refereed][Not invited]
     
    Omsk hemorrhagic fever virus (OHFV) is a member of the tick-borne encephalitis serocomplex of flaviviruses, and causes hemorrhagic disease in humans. In this study, an infectious cDNA of OHFV was constructed to investigate the molecular mechanisms involved in OHFV pathogenesis for the first time. Our cDNA clone was capable of producing infectious virus which is genetically identical to the parental Guriev strain, and the recombinant virus showed similar biological properties to the parental virus including growth kinetics and virulence characteristics. While characterizing the cDNAs, fortuitous mutations at NS2A position 46 and NS5 position 836 were found to affect viral production. By using a viral replicon expressing luciferase, it was shown that both of the mutations produced a defect in RNA replication and that the NS5 mutation induced a temperature-sensitive phenotype, indicating the importance of these residues in RNA replication. This infectious cDNA will be a useful tool to study the replication and pathogenesis of OHFV. (C) 2010 Elsevier B.V. All rights reserved.
  • Erdenesaikhan Tegshduuren, Kumiko Yoshimatsu, Midori Taruishi, Rika Endo, Kenta Shimizu, Takaaki Koma, Shumpei P. Yasuda, Hiroaki Kariwa, Jiro Arikawa, Chiaki Ishihara  COMPARATIVE IMMUNOLOGY MICROBIOLOGY AND INFECTIOUS DISEASES  33-  (6)  E67  -E73  2010/12  [Not refereed][Not invited]
     
    Tula virus (TULV) and Puumala virus (PUUV) are hantaviruses carried by the bank vole (Myodes glareolus) and European common vole (Microtus arvalis), respectively. PUUV is a causative agent of hemorrhagic fever with renal syndrome (HFRS), while TULV is thought to be apathogenic to humans. The N-terminal regions of the N proteins from TULV and PUUV were expressed and applied as enzyme-linked immunosorbent assay (ELISA) antigens. Colonized Japanese grass voles (Microtus montebelli) and BALB/c mice were used for experimental inoculation of the vole-borne hantaviruses TULV and PUUV. Voles and mice showed significant antibody production toward both viruses, but these antisera showed little cross-reactivity between TULV and PUUV in the immunofluorescence antibody assay and ELISA. In contrast, sera from patients with HFRS caused by PUUV exhibited high cross-reactivity against the TULV antigen, and sera from a natural rodent reservoir showed moderate cross-reactivity against the heterologous antigen, indicating that the antigenic cross-reactivity between TULV and PUUV differs in sera from rodents and humans. (C) 2010 Elsevier Ltd. All rights reserved.
  • Hyun-Kyoung Lee, Byoung-Hee Lee, Seung-Hyeok Seok, Min-Won Baek, Hui-Young Lee, Dong-Jae Kim, Yi-Rang Na, Kyoung-Jin Noh, Sung-Hoon Park, Dutta Noton Kumar, Hiroaki Kariwa, Mina Nakauchi, Suk-Jin Heo, Jae-Hak Park  JOURNAL OF VETERINARY SCIENCE  11-  (2)  165  -167  2010/06  [Not refereed][Not invited]
     
    Severe acute respiratory syndrome (SARS) is a life-threatening disease for which accurate diagnosis is essential. Although many tools have been developed for the diagnosis of SARS, false-positive reactions in negative sera may occur because of cross-reactivity with other coronaviruses. We have raised polyclonal and monoclonal antibodies (Abs) using a recombinant form of the SARS virus nucleocapsid protein. Cross-reactivity of these anti-SARS Abs against human coronavirus (HCoV) 229E and HCoV OC43 were determined by Western blotting. The Abs produced reacted with recombinant SARS virus nucleocapsid protein, but not with HCoV 229E or HCoV OC43.
  • Ryo Murata, Yuki Eshita, Akihiko Maeda, Junko Maeda, Saki Akita, Tomohisa Tanaka, Kentaro Yoshii, Hiroaki Kariwa, Takashi Umemura, Ikuo Takashima  AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE  82-  (4)  696  -704  2010/04  [Not refereed][Not invited]
     
    Many West Nile (WN) virus isolates associated with significant outbreaks possess a glycosylation site on the envelope (E) protein. E-protein glycosylated variants of New York (NY) strains of WN virus are more neuroinvasive in mice than the non-glycosylated variants. To determine how E protein glycosylation affects the interactions between WN virus and avian hosts, we inoculated young chicks with NY strains of WN virus containing either glycosylated or nonglycosylated variants of the E protein. The glycosylated variants were more virulent and had higher viremic levels than the non-glycosylated variants. The glycosylation status of the variant did not affect viral multiplication and dissemination in mosquitoes in vivo. Glycosylated variants showed more heat-stable propagation than non-glycosylated variants in mammalian (BHK) and avian (QT6) cells but not in mosquito (C6/36) cells. Thus, E-protein glycosylation may be a requirement for efficient transmission of WN virus from avian hosts to mosquito vectors.
  • 吉田喜香, 苅和宏明, 真田崇弘, NGONDA Saasa, 瀬戸隆弘, 吉松組子, 有川二郎, 好井健太朗, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  58th-  2010
  • Hiroaki Kariwa, Evgeniy A. Tkachenko, Vyacheslav G. Morozov, Takahiro Seto, Yoichi Tanikawa, Sergey I. Kolominov, Sergey N. Belov, Ichiro Nakamura, Nobuo Hashimoto, Alexander E. Balakiev, Tamara K. Dzagurnova, Nur Hardy bin Abu Daud, Daisuke Miyashita, Olga A. Medvedkina, Mina Nakauchi, Mariko Ishizuka, Kentaro Yoshii, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima  JOURNAL OF VETERINARY MEDICAL SCIENCE  71-  (12)  1569  -1578  2009/12  [Not refereed][Not invited]
     
    European Russia is a highly endemic area of hemorrhagic fever with renal syndrome (HFRS), a rodent-borne zoonotic disease, caused by hantaviruses. In total, 145 small mammals of four species (Myodes glareolus, Apodemus flavicollis, A. agrarius, and A. uralensis) were trapped in the Samara region of European Russia in August 2005 and examined for the presence of hantavirus (HV). Anti-HV antibodies were found in six of 68 (8.8%) M. glareolus and in one of 19 (5.3%) A. flavicollis by indirect immunofluorescent antibody assay (IFA). The Puumala virus (PUUV), which is one of the hantavirus species, was detected in the lungs of seven M. glareolus by RT-PCR. The virus S-segment was extremely similar (96.2% to 99.3%) to the sequence found in a fatal case of HFRS in the Samara region. Phylogenetic analyses of S and M segments showed that the Samara PUUVs form a cluster within the Russian Volga lineage and apparently differ from other European PUUVs. Anti-PUUV antibodies were found in blood sera from seven HFRS patients and from one undiagnosed patient from the Samara region, using IFA and an enzyme-linked immunosorbent assay (ELISA). These data Suggest that the bank vole M. glareolus is a primary natural reservoir and vector for PUUV, which is the main causative agent of HFRS in humans in the Samara region.
  • Kentaro Yoshii, Ayae Ikawa, Yumiko Chiba, Yuki Omori, Junko Maeda, Ryo Murata, Hiroaki Kariwa, Ikuo Takashima  JOURNAL OF VIROLOGICAL METHODS  161-  (1)  173  -176  2009/10  [Not refereed][Not invited]
     
    Previously, a system for packaging tick-borne encephalitis virus (TBEV) subgenomic replicon RNAs into single-round infectious virus-like particles (VLPs) was developed. In the present study, VLPs were applied to measuring the levels of neutralizing antibodies against TBEV as an alternative to performing neutralization tests with live virus. As markers of VLP infection, the genes for GFP and luciferase were inserted into the TBEV replicon, which was then packaged into VLPs. The reporter genes were expressed in cells that were infected with the VLPs, and this infection was inhibited by neutralizing antibodies to TBEV. Serum samples from wild rodents were used to evaluate the neutralization test using VLPs. All the sera that were positive in the conventional neutralization test were also found to be positive in the neutralization test using VLPs, and there were highly significant correlations between the neutralization titres obtained using the native virus and those using VLPs. These results indicate that VLPs that express reporter genes represent a useful and safe alternative to conventional neutralization testing using live virus. (C) 2009 Elsevier B.V. All rights reserved.
  • Akihiko Maeda, Ryo Murata, Minoru Akiyama, Ikuo Takashima, Hiroaki Kariwa, Tomomasa Watanabe, Ichiro Kurane, Junko Maeda  VIRUS RESEARCH  144-  (1-2)  35  -43  2009/09  [Not refereed][Not invited]
     
    Viral reverse genetics, particularly infectious cloning, is a valuable tool with applications to many areas of viral research including the generation of vaccine candidates. However, this technology is sometimes insufficient for the construction cDNA clones as the genome sequences and/or encoding proteins of some viral agents may be toxic to the host cells used for cloning. To circumvent this problem, we developed a polymerase chain reaction (PCR)-based protocol for generating a complete West Nile virus (WNV) cDNA. The fragmented cDNAs were synthesized from WNV RNA by reverse transcription-PCR, and subsequently cloned into plasmids for use as templates for WNV cDNA synthesis. The fragmented cDNAs were amplified and assembled by PCR to generate a full-length WNV cDNA. Using this ONA as a template, WNV RNA was synthesized in vitro and transfected into mammalian cells. We also examined the generation of a mutant recombinant WNV containing a site-directed mutation within the viral genome sequence. Here, we discuss the possibility of developing a method for the generation of recombinant WNVs. (C) 2009 Elsevier B.V. All rights reserved.
  • Kanako Moritoh, Hideto Yamauchi, Atsushi Asano, Kentaro Yoshii, Hiroaki Kariwa, Ikuo Takashima, Norikazu Isoda, Yoshihiro Sakoda, Hiroshi Kida, Nobuya Sasaki, Takashi Agui  JAPANESE JOURNAL OF VETERINARY RESEARCH  57-  (2)  89  -99  2009/08  [Not refereed][Not invited]
     
    Mx1 (Myxovirus resistance protein) and Oas1b (Oligoadenylate synthetase-1), induced by type 1 interferon (IFN), play a role in early antiviral innate immunity by inhibiting the replication of viruses. In mice, Mx1 and Oas1b confer resistance to the infection of orthomyxoviruses including influenza viruses and flaviviruses including West Nile viruses, respectively. Laboratory mice have been used to study the mechanisms of the pathogenesis of these virus infections; however, it is possible that they are not a suitable model system to study these viruses, since most of the inbred laboratory mouse strains lack both genes. It has been reported that feral mouse-derived inbred strains show resistance to the infection of these viruses due to the presence of intact both genes. In this study, we generated congenic strains in which the Mx or Oas locus of the MSM/Ms (MSAI) mouce was introduced to the most widely used mouse strain, C57BL/6J (136). B6.MSM-Mx mice showed resistance to the infection of influenza virus but not of West Nile virus. On the other hand, B6.MSM-Oas mice showed resistance to the infection of West Nile virus but not of influenza virus. Our results indicate that Mx1 and Oas1b show highly antiviral specificity in mice possessing the same genetic background. Therefore, these congenic mice are useful for not only infection study but also investigation of host defense mechanism to these viruses.
  • 苅和 宏明  臨床とウイルス  37-  (2)  S26  2009/04/30
  • 遠藤理香, 吉松組子, 駒貴明, 清水健太, 安田俊平, TEGSHDUUREN Erdenesaihan, 垂石みどり, 海老原秀喜, 宮下大輔, 瀬戸隆弘, HERNANDEZ Cornelio S., ALMARAZ Maria L.R., RAMOS Celso, 苅和宏明, 高島郁夫, 有川二郎  日本ウイルス学会学術集会プログラム・抄録集  57th-  2009
  • 駒貴明, 吉松組子, 垂石みどり, 遠藤理香, 清水健太, 安田俊平, エルテネサイハンテグシドーレン, 海老原秀喜, HERNANDEZ Cornelio S., ALMARAZ Maria L.R., RAMOS Celso, 宮下大輔, 瀬戸隆弘, 苅和宏明, 高島郁夫, ENRIA Delia, 有川二郎  日本ウイルス学会学術集会プログラム・抄録集  57th-  2009
  • 駒貴明, 吉松組子, 垂石みどり, 遠藤理香, 清水健太, 安田俊平, テグシドーレン エルデネサイハン, 海老原秀喜, HERNANDEZ Cornelio S., ALMARAZ Maria L.R., RAMOS Celso, 宮下大輔, 瀬戸隆弘, 苅和宏明, 高島郁夫, ENRIA Delia, 有川二郎  日本ウイルス学会北海道支部夏季シンポジウム講演抄録  43rd-  2009
  • 真田崇弘, 苅和宏明, 瀬戸隆弘, 谷川洋一, 宮下大輔, 吉松組子, 有川二郎, 好井健太朗, 高島郁夫  日本ウイルス学会北海道支部夏季シンポジウム講演抄録  43rd-  2009
  • Mina Nakauchi, Hiroaki Kariwa, Yasuhiro Kon, Kentaro Yoshii, Akihiko Maeda, Ikuo Takashima  MICROBIOLOGY AND IMMUNOLOGY  52-  (12)  625  -630  2008/12  [Not refereed][Not invited]
     
    SARS-CoV has four major structural proteins: the N, S, M, and E proteins. To investigate the mechanism of SARS-CoV assembly, we cloned the genes encoding these four proteins into the eukaryotic expression vector pCAGGS and transfected them into 293T cells. When all four expression vectors were co-transfected VLP formed, as confirmed using electron microscopy. Using a rabbit polyclonal antibody specific to the N protein, N-protein-containing particles similar in size to the VLP were also observed by immunoelectron microscopy, indicating that the VLP contained the N protein. Co-immunoprecipitation analyses demonstrated an interaction between the N and M proteins, suggesting that N protein binds directly to M protein to be incorporated into VLP.
  • Nur Hardy Abu Daud, Hiroaki Kariwa, Evgeniy Tkachenko, Tamara Dzagurnova, Olga Medvedkina, Petr Tkachenko, Mariko Ishizuka, Takahiro Seto, Daisuke Miyashita, Takahiro Sanada, Mina Nakauchi, Kentaro Yoshii, Akihiko Maeda, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima  JAPANESE JOURNAL OF VETERINARY RESEARCH  56-  (3)  151  -165  2008/11  [Not refereed][Not invited]
     
    Puumala virus (PUUV), a causative agent of hemorrhagic fever with renal syndrome (HFRS), is prevalent in Europe and European Russia. No vaccine has been developed for PUUV-associated HFRS, primarily because of the low viral yield in cultured cells. A PUUV strain known as DTK/Ufa-97 was isolated in Russia and adapted for growth in Vero E6 cells maintained in serum-free medium. The DTK/Ufa-97 strain produced a higher viral titer in serum-free medium, suggesting that it may prove useful in the development of an HFRS vaccine. When PUUV-infected Vero E6 cells were grown in serum-free medium, the DTK/Ufa-97 strain yielded more copies of intracellular viral RNA and a higher viral titer in the culture fluid than did the Sotkamo strain. Phylogenetic analysis revealed that PUUVs can be classified into multiple lineages according to geographical origin, and that the DTK/Ufa-97 strain is a member of the Bashkiria-Saratov lineage. The deduced amino acid sequences of the small, medium, and large segments of the DTK/Ufa-97 strain were 99.2% to 100%, 99.3% to 99.8%, and 99.8% identical, respectively, to those of the Bashkirian PUUV strains and 96.9%, 92.6%, and 97.4% identical, respectively, to those of the Sotkamo strain, indicating that the PUUVs are genetically diverse. However, DTK/Ufa-97 and other strains of PUUV exhibited similar patterns of binding to a panel of monoclonal antibodies against Hantaan virus. In addition, diluted antisera (i.e., ranging from 1:160 to 1:640) specific to three strains of PUUV neutralized both homologous and heterologous viruses. These results suggest that the DTK/Ufa-97 strain is capable of extensive growth and is antigenically similar to genetically distant strains of PUUV.
  • Hyun-Kyoung Lee, Byoung-Hee Lee, Noton Kumar Dutta, Seung-Hyeok Seok, Min-Won Baek, Hui-Young Lee, Dong-Jae Kim, Yi-Rang Na, Kyoung-Jin Noh, Sung-Hoon Park, Hiroaki Kariwa, Mina Nakauchi, Le Quynh Mai, Suk-Jin Heo, Jae-Hak Park  JOURNAL OF MICROBIOLOGY AND BIOTECHNOLOGY  18-  (10)  1717  -1721  2008/10  [Not refereed][Not invited]
     
    Severe acute respiratory syndrome (SARS) is a life-threatening emerging respiratory disease caused by the coronavirus, SARS-CoV The nucleocapsid (N) protein of SARS-CoV is highly antigenic and may be a suitable candidate for diagnostic applications. We constructed truncated recombinant N proteins (N1 |1-422 aa|, N2 |-109 aa|, and N3 |110-422 aa|) and determined their antigenicity by Western blotting using convalescent SARS serum. The recombinants containing N1 and N3 reacted with convalescent SARS serum in Western blotting. However, the recombinant with N2 did not. In ELISA using N1 or N3 as the antigens. positive results were observed in 10 of 10 (100%,) SARS-CoV-positive human sera. None of 50 healthy sera gave positive results in either assay. These data indicate that the ELISA using NI or N3 has high sensitivity and specificity. These results suggest that the middle or C-terminal region of the SARS N protein is important for eliciting antibodies against SARS-CoV during, the immune response, and ELISA reactions using N1 or N3 may be a valuable tool for SARS diagnosis.
  • Ichiro Nakamura, Kumiko Yoshimatsu, Byoung-Hee Lee, Megumi Okumura, Midori Taruishi, Koichi Araki, Hiroaki Kariwa, Ikuo Takashima, Jiro Arikawa  ARCHIVES OF VIROLOGY  153-  (8)  1537  -1542  2008/08  [Not refereed][Not invited]
     
    To distinguish Thailand virus infection from infections with other hantaviruses, we established an ELISA serotyping system using a truncated nucleocapsid protein of Thailand virus lacking 49 amino acids at the N-terminus. In evaluations using patient and rodent sera, Thailand virus infection was readily distinguished from Hantaan and Seoul virus infections. Therefore, this ELISA system is an effective alternative to neutralization tests.
  • Noton Kumar Dutta, Kaushiki Mazumdar, Byoung-Hee Lee, Min-Won Baek, Dong-Jae Kim, Yi-Rang Na, Sung-Hoon Park, Hyun-Kyoung Lee, Hiroaki Kariwa, Le Quynh Mai, Jae-Hak Park  IMMUNOLOGY LETTERS  118-  (1)  65  -71  2008/06  [Not refereed][Not invited]
     
    It is believed today that nucleocapsid protein (N) of severe acute respiratory syndrome (SARS)-CoV is one of the most promising antigen candidates for vaccine design. In this study, three fragments [NI (residues: 1-422); N2 (residues: 1-109); N3 (residues: 110-422)] of N protein of SARS-CoV were expressed in Escherichia coli and analyzed by pooled sera of convalescence phase of SARS patients. Three gene fragments [N1 (1-1269 nt), N2 (1-327 nt) and N3 (328-1269 nt)-expressing the same proteins of NI, N2 and N3, respectively] of SARS-N were cloned into pVAX-1 and used to immunize BALB/c mice by electroporation. Humoral (by enzyme-linked immunosorbent assay, ELISA) and cellular (by cell proliferation and CD4(+):CD8(+) assay) immunity was detected by using recombinant N1 and N3 specific antigen. Results showed that NI and N3 fragments of N protein expressed by E. coli were able to react with sera of SARS patients but N2 could not. Specific humoral and cellular immunity in mice could be induced significantly by inoculating SARS-CoV N1 and N3 DNA vaccine. In addition, the immune response levels in N3 were significantly higher for antibody responses (IgG and IgG1 but not IgG2a) and cell proliferation but not in CD4(+):CD8(+) assay compared to N1 vaccine. The identification of antigenic N protein fragments has implications to provide basic information for the design of DNA vaccine against SARS-CoV. The present results not only suggest that DNA immunization with pVax-N3 could be used as potential DNA vaccination approaches to induce antibody in BALB/c mice, but also illustrates that gene immunization with these SARS DNA vaccines can generate different immune responses. (c) 2008 Elsevier B.V. All rights reserved.
  • Hiroaki Kariwa, Hiroshi Noda, Mina Nakauchi, Mariko Ishizuka, Kazuaki Hashiguchi, Shingo Hashimoto, Kentaro Yoshii, Atsushi Asano, Takashi Agui, Hiroyuki Kogaki, Yoshihiro Kurano, Yoshiaki Uchida, Nobuyuki Fuji, Masahisa Okada, Ikuo Takashima  JAPANESE JOURNAL OF VETERINARY RESEARCH  55-  (4)  115  -127  2008/02  [Not refereed][Not invited]
     
    The sudden emergence of severe acute respiratory syndrome (SARS) at the end of 2002 resulted in 774 reported deaths from more than 8000 cases worldwide. As no effective vaccines or antiviral agents are available, the most effective measure to prevent the expansion of a SARS epidemic is the rapid diagnosis and isolation of SARS patients. To establish specific diagnostic methods, we generated nine clones of monoclonal antibodies to nucleocapsid protein (NP) of SARS-coronavirus (SARS-CoV). On immunofluorescent antibody assay and Western blotting analysis, none of the monoclonal antibodies showed cross-reactivity to authentic and recombinant NPs of human coronavirus (HCoV) 229E strain. To determine the region on the NP molecule where the monoclonal antibodies bind, we generated four truncated recombinant NPs and analyzed the reactivity between monoclonal antibodies and truncated NPs. Two monoclonal antibodies reacted with a truncated NP covering from amino acid residues 111 to 230, and seven reacted with another truncated NP covering from amino acid residues 221 to 340. Epitope mapping analysis indicated that monoclonal antibody SN5-25 recognized the amino acid sequence Q(245)TVTKW(250) on SARS-NP. Within the epitope, Q245, T246, V247, K249, and K250 appeared to form an essential motif for monoclonal antibody SN5-25 to bind. The information about binding sites and epitopes of monoclonal antibodies may be useful for the development of new diagnostic methods for SARS and for analyzing the function of N protein of SARS-CoV.
  • Kentaro Yoshii, Akiko Goto, Kazue Kawakami, Hiroaki Kariwa, Ikuo Takashima  JOURNAL OF GENERAL VIROLOGY  89-  (1)  200  -211  2008/01  [Not refereed][Not invited]
     
    We have previously reported a system for packaging tick-borne encephalitis (TBE) virus subgenomic replicon RNAs into single-round infectious virus-like particles (VLPs) by using in trans expression of viral C/prM/E structural proteins. In this study, the trans-packaging system was applied to the generation of chimeric VLPs with mosquito-borne Japanese encephalitis (JE) virus. Although trans-expression of TBE virus C and JE virus prM/E proteins resulted in the secretion of VLPs, the expression of JE virus C/prM/E proteins did not lead to the secretion of VLPs, suggesting that homologous interaction between C and non-structural proteins or the genomic RNA is important for efficient assembly of infectious particles. Neutralization testing showed that the antigenic characteristics of the VLPs; were similar to those of the native virus. Furthermore, the infectivities of the TBE virus- and JE virus-enveloped VLPs for the ISE6 tick cell line and C6/36 mosquito cell line were investigated. The VLPs were able to enter only those cells that were derived from the natural vectors for the respective viruses. TBE virus replicon RNA packaged in VLPs produced TBE virus non-structural proteins in tick cells, but could neither replicate nor produce viral proteins in mosquito cells. These findings indicate the importance of specific cellular factors for virus entry and replication during flavivirus infection of arthropods. These results demonstrate that chimeric VLPs are useful tools for the study of viral genome packaging and cellular factors involved in vector specificity, with the additional safety aspect that these chimeric VLPs can be used instead of full-length chimeric viruses.
  • 瀬戸隆弘, 苅和宏明, 谷川洋一, 吉松組子, 中村一郎, 宮下大輔, 中内美名, 好井健太朗, 有川二郎, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  55th-  2007
  • 瀬戸隆弘, 苅和宏明, 谷川洋一, AD Nur Hardy, 中村一郎, 宮下大輔, 好井健太郎, 高島郁夫  日本獣医学会学術集会講演要旨集  143rd-  2007
  • 宮下大輔, 苅和宏明, 村田亮, NUR Hardy A D, 瀬戸隆弘, 好井健太郎, 高島郁夫  日本獣医学会学術集会講演要旨集  144th-  2007
  • 宮下大輔, 苅和宏明, 瀬戸隆弘, 好井健太郎, 吉松組子, 有川二郎, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  55th-  2007
  • Nur Hardy Abu Daud, Hiroaki Kariwa, Yoich Tanikawa, Ichiro Nakamura, Takahiro Seto, Daisuke Miyashita, Kentaro Yoshii, Mina Nakauchi, Kumiko Yoshimatsu, Jiro Arikawa, Ikuo Takashima  MICROBIOLOGY AND IMMUNOLOGY  51-  (11)  1081  -1090  2007  [Not refereed][Not invited]
     
    Hokkaido virus (HOKV) is a member of the genus Hantavirus, in the family Bunyaviridae. To investigate HOKV infection in the host Myodes rufocanus, the grey red-backed vole, 199 animals were captured at Tobetsu (October 2004 and July 2005) and Nakagawa (October 2004) in Hokkaido, Japan, for detection of antibody, antigen, and viral RNA. In the surveys in Tobetsu (2004) and Nakagawa (2004), seropositive animals were detected at a frequency of 6.0% (5/84) and 10.4% (5/48), respectively. No seropositive animals were detected in Tobetsu in 2005. Seroprevalence in males in Tobetsu and Nakagawa in 2004 was 25 % (1/4) and 45.5 % (5111), respectively, which was higher than in females, at 5.0 % (4/80) and 0% (0/37), respectively (P<0.01). These results suggest that male animals play an important role in the maintenance of HOKV in M. rufocanus. Two females were seronegative but viral RNA-positive, indicating that these animals had acute infections before antibody was produced. Another five infected animals in Nakagawa were all male and had high levels of antibodies and viral RNA, suggesting that they had persistent infections. Viral RNA copies in organs of infected animals in Nakagawa were quantified by real-time polymerase chain reaction. Two acutely infected animals had >= 10 times the number of RNA copies in their lungs compared to those of persistently infected animals. In most cases, lungs or spleen had the highest RNA copy number, regardless of infection status.
  • Sirima Pattamadilok, Byoung-Hee Lee, Sanit Kumperasart, Kumiko Yoshimatsu, Megumi Okumura, Ichiro Nakamura, Koichi Araki, Yuvaluk Khoprasert, Prayadh Dangsupa, Pornpitak Panlar, Burkhard Jandrig, Detlev H. Krueger, Boris Klempa, Thomas Jaekel, Jonas Schmidt, Rainer Ulrich, Hiroaki Kariwa, Jiro Arikawa  AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE  75-  (5)  994  -1002  2006/11  [Not refereed][Not invited]
     
    Phylogenetic investigations, sequence comparisons, and antigenic cross-re activity studies confirmed the classification of Thailand virus (THAIV) as a distinct hantavirus species. The examination of sera from 402 rodents trapped in 19 provinces of Thailand revealed that five greater bandicoot rats (Bandicota indica) and one lesser bandicoot rat (B. savilei) from four provinces were focus reduction neutralization test (FRNT) antibody-positive for THAIV. One of 260 patients from Surin province in Thailand (initially suspected of having contracted leptospirosis, but found to be negative) showed symptoms compatible with hemorrhagic fever with renal syndrome (HFRS). The serum of this patient showed high titers of hantavirus-reactive IgM and IgG. FRNT investigations confirmed virus-neutralizing antibodies against THAIV. These observations suggest that THAIV or THAI-like viruses occur throughout Indochina and may represent an additional causative agent of HFRS.
  • Kazuya Shirato, Hirotsugu Miyoshi, Hiroaki Kariwa, Ikuo Takashima  VIRUS RESEARCH  121-  (1)  11  -16  2006/10  [Not refereed][Not invited]
     
    The envelope (E) protein glycosylation status of the New York strain of West Nile (WN) virus is an important determinant of virus neuroinvasiveness. To elucidate the determinant of the difference between E protein-glycosylated and non-glycosylated WN virus infections, the cytokine expression of murine peritoneal macrophages infected with each virus was examined. Tumor necrosis factor (TNF) alpha and interleukin (IL)-1 beta were up-regulated with replication of the E protein-glycosylated virus. Interferon (IFN) beta and IL-6 were up-regulated with the clearance of both viruses. These results suggest that TNF alpha and IL-1 beta expression are related to the virulence of E protein-glycosylated WN virus. (c) 2006 Elsevier B.V. All rights reserved.
  • M Obara, K Yoshii, T Kawata, D Hayasaka, A Goto, T Mizutani, H Kariwa, Takashima, I  JOURNAL OF VIROLOGICAL METHODS  134-  (1-2)  55  -60  2006/06  [Not refereed][Not invited]
     
    The similarity of symptoms produced by tick-borne encephalitis (TBE) and Japanese encephalitis (JE) and the high degree of cross-reactivity between TBE and JE viruses by serological tests make the development of a differential diagnostic test a priority. In this study, recombinant prM/E proteins of TBE virus strain Oshima 5-10 expressed in mammalian cells resulted in the release of subviral particles (SPs) into the culture medium. Using the SPs as antigens, enzyme-linked immunosorbent assay (ELISA) systems were developed to detect TBE virus-specific IgM and IgG antibodies, designated SP-IgG and SP-IgM ELISAs, respectively. Of 83 serum samples from encephalitis patients in Khabarovsk, Russia, which were positive with the neutralization test (NT), 82 were positive by the SP-IgG ELISA, for a sensitivity of 98.8%, which was higher than that of a commercial ELISA kit. All 12 NT-negative samples were also negative by the SP-IgG ELISA (specificity, 100%). Of 17 patient samples that were NT-positive, 16 (94.1%) were positive by the SP-IgM ELISA. Of 15 paired serum samples that yielded equivocal results by NT, 11 had positive results with the SP-IgM ELISA, indicating a diagnosis of TBE infection. The SP-IgG and SP-IgM ELISAs showed no cross-reactivity with antibodies to the JE virus. The results indicate that these ELISAs will be useful for the detection of TBE-specific antibodies. (c) 2005 Elsevier B.V. All rights reserved.
  • T Okabayashi, H Kariwa, S Yokota, S Iki, T Indoh, N Yokosawa, Takashima, I, H Tsutsumi, N Fujii  JOURNAL OF MEDICAL VIROLOGY  78-  (4)  417  -424  2006/04  [Not refereed][Not invited]
     
    The pathogenesis of severe acute respiratory syndrome (SARS) is poorly understood and cytokine dysregulation has been suggested as one relevant mechanism to be explored. We compared the cytokine profile in Caco2 cells after infection of SARS coronavirus (SARS-CoV) with other respiratory viruses including respiratory syncytial virus (RSV), influenza A virus (FluAV), and human parainfluenza virus type 2 (hPIV2). Interferon (IFN) system (production and response) was not suppressed by SARS-CoV infection. Therefore, SARS-CoV replication was suppressed by pretreatment with IFN. SARS-CoV and RSV induced high levels of IL-6 and RANTES compared with FluAV and hPIV2. Induction level of suppressor of cytokine signaling-3 (SOCS3) by SARS-CoV was significantly lower than that by RSV in spite of the significant production of IL-6. Toll-like receptors 4 and 9, which correlate with the induction of inflammatory response, were upregulated by SARS-CoV infection. Collectively, overinduction of inflammatory cytokine and dysregulation of cytokine signaling may contribute to the immunopathology associated with "severe" inflammation in SARS.
  • LJ Baek, H Kariwa, K Lokugamage, K Yoshimatsu, J Arikawa, Takashima, I, JI Kang, SS Moon, SY Chung, EJ Kim, HJ Kang, KJ Song, TA Klein, R Yanagihara, JW Song  JOURNAL OF MEDICAL VIROLOGY  78-  (2)  290  -297  2006/02  [Not refereed][Not invited]
     
    Hantaan (HTN) virus, the etiologic agent of clinically severe hemorrhagic fever with renal syndrome (HFRS), was first isolated in 1976 from lung tissue of a striped-field mouse (Apodemus agrarius) captured in Songnae-ri, Gyeonggi Province, Republic of Korea. Found primarily in mountainous areas, the Korean field mouse (A. peninsulae) is the second-most dominant field rodent species found throughout Korea. A new hantavirus, designated Soochong (SOO), was isolated in Vero E6 cells from four A. peninsulae captured in August 1997 at Mt. Gyebang in Hongcheon-gun, Mt. Gachil, Inje-gun, Gangwon Province, and in September 1998 at Mt. Deogyu, Muju-gun, Jeollabuk Province. The entire S, M, and L genomic segments of SOO virus, amplified by RT-PCR from lung tissues of seropositive A. peninsulae and from virus-infected Vero E6 cells, diverged from HTN virus (strain 76-118) by 15.6%, 22.8%, and 21.7% at the nucleotide level and 3.5%, 9.5%, and 4.6% at the amino acid level, respectively. Phylogenetic analyses of the nucleotide and deduced amino acid sequences, using the maximum parsimony and neighbor-joining methods, indicated that SOO virus was distinct from A. agrarius-borne HTN virus. SOO virus shared a common ancestry with Amur virus from Far East Russia, as well as with H5 and B78 hantaviruses, previously isolated from HFRS patients in China. Cross-focus-reduction neutralizating antibody tests showed that SOO virus which is the first hantavirus isolated in cell culture from A. peninsulae, could be classified as a new hantavirus serotype.
  • 好井健太朗, 小原真弓, 小原真弓, 後藤明子, 苅和宏明, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  54th-  2006
  • H Kariwa, N Fujii, K Takashima  DERMATOLOGY  212-  (Suppl 1)  119  -123  2006  [Not refereed][Not invited]
     
    The efficacy of several povidone-iodine (PVP-I) products, a number of other chemical agents and various physical conditions were evaluated for their ability to inactivate the severe acute respiratory syndrome coronavirus; (SARS-CoV). Treatment of SARS-CoV with PVP-I products for 2 min reduced the virus infectivity from 1.17 x 10(6) TCID50/ml to below the detectable level. The efficacy of 70% ethanol was equivalent to that of PVP-I products. Fixation of SARS-CoV-infected Vero E6 cells with a fixative including formalin, glutaraldehyde, methanol and acetone for 5 min or longer eliminated all infectivity. Heating the virus at 56 degrees C for 60 min or longer reduced the infectivity of the virus from 2.6 x 10(7) to undetectable levels. Irradiation with ultraviolet light at 134 mu W/cm(2) for 15 min reduced the infectivity from 3.8 x 10(7) to 180 TCID50/ml; however, prolonged irradiation (60 min) failed to eliminate the remaining virus, leaving 18.8 TCID50/ml. Copyright (c) 2006 S. Karger AG, Basel.
  • 苅和 宏明  Virus report  2-  (2)  27  -34  2005/11
  • K Yoshii, D Hayasaka, A Goto, K Kawakami, H Kariwa, Takashima, I  VACCINE  23-  (30)  3946  -3956  2005/06  [Not refereed][Not invited]
     
    The sub-genomic replicon of tick-borne encephalitis (TBE) virus (Far-Eastern subtype) was packaged into infectious particles by providing the viral structural proteins in trans. Sequential transfection of TBE replicon RNA and a plasmid that expressed the structural proteins led to the secretion of infectious particles that contained TBE replicon RNA. The secreted particles had single-round infectivity, which was inhibited by TBE virus-neutralizing antibody. The physical structure of the particles was almost identical to that of infectious virions, and the packaged replicon RNA showed no recombination with the mRNAs of the viral structural proteins. Furthermore, heterologous genes were successfully delivered and expressed by packaging TBE replicon RNA with inserted GFP and Neo, genes. This replicon packaging system may be a useful tool for the molecular study of the TBE virus genome packaging mechanism, and for the development of vaccine delivery systems. (c) 2005 Elsevier Ltd. All rights reserved.
  • K Shirato, H Miyoshi, H Kariwa, Takashima, I  JOURNAL OF VIROLOGICAL METHODS  126-  (1-2)  119  -125  2005/06  [Not refereed][Not invited]
     
    A diagnostic method to distinguish between West Nile virus (WNV) and Japanese encephalitis virus (JEV) based on fluorogenic real-time polymerase chain reaction (TaqMan) assays was developed. To detect WNV and JEV with a single probe, a probe was designed to correspond to sequences in the core protein region that are shared by both viruses. The specificity of this assay depended on the primer sets used, which were specific to the target virus sequences: the primer set for WNV Could detect only WNV strains and the primer set for JEV could detect only JEV strains. The assays were tested by detection of viruses from experimentally infected animal tissues. The method described in this study will be useful for the simultaneous discrimination of WNV and JEV in areas where JEV is endemic, such as East Asia. © 2005 Elsevier B.V. All rights reserved.
  • 好井健太朗, 後藤明子, 小原真弓, 伊川綾恵, 苅和宏明, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  53rd-  2005
  • 好井健太朗, 後藤明子, 小原真弓, 伊川綾恵, 苅和宏明, 高島郁夫  日本分子生物学会年会講演要旨集  28th-  2005
  • Kogaki, H., Uchida, Y., Fujii, N., Kurano, Y., Miyake, K., Kido, Y., Kariwa, H., Takashima, I., Tamashiro, H., Ling, A.E., and Okada, M.:"Novel rapid immunochromatographic test based on an enzyme immunoassay for detecting nucleocapsid antigen in SARS-a・・・
    2005  [Not refereed][Not invited]
     
    Kogaki, H., Uchida, Y., Fujii, N., Kurano, Y., Miyake, K., Kido, Y., Kariwa, H., Takashima, I., Tamashiro, H., Ling, A.E., and Okada, M.:"Novel rapid immunochromatographic test based on an enzyme immunoassay for detecting nucleocapsid antigen in SARS-associated coronavirus", J Clin Lab Anal, 19:150-159. (2005)*
  • Goto, A., Yoshii, K., Obara, M., Ueki, T., Mizutani, T., Kariwa, H., and Takashima, I.:"Role of the N-linked glycans of the prM and E envelope proteins in tick-borne encephalitis virus particle secretion", Vaccine, 23:3043-3052(2005)*
    2005  [Not refereed][Not invited]
  • H Kariwa, N Fujii, Takashima, I  JAPANESE JOURNAL OF VETERINARY RESEARCH  52-  (3)  105  -112  2004/11  [Not refereed][Not invited]
     
    number of other chemical agents, and various physical conditions were evaluated for their ability to inactivate the severe acute respiratory syndrome coronavirus (SARS-CoV). Treatment of SARS-CoV with PVP-I products for 2 min reduced the virus infectivity from 1.17 x 10(6) TCID50/Ml to below the detectable level. The efficacy of 70% ethanol was equivalent to that of PVP-I products. Fixation of SARS-CoV-infected Vero E6 cells with a fixative including formalin, glutaraldehyde, methanol, and acetone for 5 min or longer eliminated all infectivity. Heating the virus at 56degreesC for 5 min dramatically reduced the infectivity of the virus from 2.6 x 10(7) to 40 TCID50/ml, whereas heating the virus for 60 min or longer eliminated all infectivity. Irradiation with ultraviolet light at 134mu W/cm(2) for 15 min reduced the infectivity from 3.8 x 10(7) to 180 TCID50/ml; however, prolonged irradiation (60 min) failed to eliminate the remaining virus, leaving 18.8 TCID50/ml. We believe that these findings will be useful for the implementation of infection control measures against SARS, and for the establishment of effective guidelines for the prevention of SARS outbreaks.
  • MA Iwasa, H Kariwa, BZ Cui, K Lokugamage, N Lokugamage, T Hagiya, T Mizutani, Takashima, I  ARCHIVES OF VIROLOGY  149-  (5)  929  -941  2004/05  [Not refereed][Not invited]
     
    To elucidate the mode of transmission of Puumala-related hantavirus in a population of gray red-backed voles, Clethrionomys rufocanus bedfordiae, in Hokkaido, Japan, we analyzed the kin structure and dispersal patterns of individual voles using microsatellite and mitochondrial DNA markers. Siblings or dam/offsprings was identified within the population based on the relatedness calculation with the microsatellite data. The pairwise relatedness values obtained could reveal kinship among all vole individuals within the population. Based on the assessment of kinship, we did not find a positive relationship between hantavirus transmission and close kinship. Males infected with the hantavirus carried a relatively uncommon mitochondrial haplotype. However, these infected males shared low relatedness values and were not considered closely related, i.e., they were not siblings or parent/offspring. These observations imply that hantavirus transmission in the vole population may not be related to close kinship but by random horizontal infection.
  • 好井健太朗, 早坂大輔, 後藤明子, 苅和宏明, 小西英二, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  52nd-  2004
  • 白戸憲也, 三好洋嗣, 後藤明子, 赤穂芳彦, 植木智隆, 苅和宏明, 高島郁夫  日本獣医学会学術集会講演要旨集  137th-  2004
  • 白戸憲也, 三好洋嗣, 後藤明子, 赤穂芳彦, 植木智隆, 苅和宏明, 高島郁夫  日本ウイルス学会学術集会プログラム・抄録集  52nd-  2004
  • 好井健太朗, 早坂大輔, 後藤明子, 川上和江, 小西英二, 苅和宏明, 高島郁夫  日本分子生物学会年会プログラム・講演要旨集  27th-  2004
  • Zamoto A, Tsuji M, Wei Q, Cho SH, Shin EH, Kim TS, Leonova GN, Hagiwara K, Asakawa M, Kariwa H, Takashima I, Ishihara C. Epizootiologic survey for Babesia microti among small wild mammals in northeastern Eurasia and a geographic diversity in the beta-t・・・
    2004  [Not refereed][Not invited]
     
    Zamoto A, Tsuji M, Wei Q, Cho SH, Shin EH, Kim TS, Leonova GN, Hagiwara K, Asakawa M, Kariwa H, Takashima I, Ishihara C. Epizootiologic survey for Babesia microti among small wild mammals in northeastern Eurasia and a geographic diversity in the beta-tubulin gene sequences. J Vet Med Sci. 66(7):785-792, 2004*
  • Kazuya Shirato, Hirotsugu Miyoshi, Akiko Goto, Yoshihiko Ako, Tomotaka Ueki, Hiroaki Kariwa, Ikuo Takashima  The Journal of general virology  85-  (Pt 12)  3637  -3645  2004  [Not refereed][Not invited]
     
    Two New York (NY) strains of the West Nile (WN) virus were plaque-purified and four variants that had different amino acid sequences at the N-linked glycosylation site in the envelope (E) protein sequence were isolated. The E protein was glycosylated in only two of these strain variants. To determine the relationship between E protein glycosylation and pathogenicity of the WN virus, 6-week-old mice were infected subcutaneously with these variants. Mice infected with viruses that carried the glycosylated E protein developed lethal infection, whereas mice infected with viruses that carried the non-glycosylated E protein showed low mortality. In contrast, intracerebral infection of mice with viruses carrying either the glycosylated or non-glycosylated forms of the E protein resulted in lethal infection. These results suggested that E protein glycosylation is a molecular determinant of neuroinvasiveness in the NY strains of WN virus.
  • Lokugamage K, Kariwa H, Lokugamage N, Iwasa M, Hagiya T, Araki K, Tachi A, Mizutani T, Yoshimatsu K, Arikawa J, Iwasaki T, Takashima I. Comparison of virulence of various hantaviruses related to hemorrhagic fever with renal syndrome in newborn mouse mo・・・
    2004  [Not refereed][Not invited]
     
    Lokugamage K, Kariwa H, Lokugamage N, Iwasa M, Hagiya T, Araki K, Tachi A, Mizutani T, Yoshimatsu K, Arikawa J, Iwasaki T, Takashima I. Comparison of virulence of various hantaviruses related to hemorrhagic fever with renal syndrome in newborn mouse model. Jpn J Vet Res. 51(3-4): 143-149, 2004.*
  • Araki K, Yoshimatsu K, Lee BH, Okumura M, Kariwa H, Takashima I, Arikawa J. Age-dependent hantavirus-specific CD8(+) T-cell responses in mice infected with Hantaan virus. Arch Virol. 149(7): 1373-1382, 2004.*
    2004  [Not refereed][Not invited]
  • Lokugamage N, Kariwa H, Lokugamage K, Iwasa MA, Hagiya T, Yoshii K, Tachi A, Ando S, Fukushima H, Tsuchiya K, Iwasaki T, Araki K, Yoshimatsu K, Arikawa J, Mizutani T, Osawa K, Sato H, Takashima I. Epizootiological and epidemiological study of hantavir・・・
    2004  [Not refereed][Not invited]
     
    Lokugamage N, Kariwa H, Lokugamage K, Iwasa MA, Hagiya T, Yoshii K, Tachi A, Ando S, Fukushima H, Tsuchiya K, Iwasaki T, Araki K, Yoshimatsu K, Arikawa J, Mizutani T, Osawa K, Sato H, Takashima I. Epizootiological and epidemiological study of hantavirus infection in Japan. Microbiol Immunol. 48(11): 843-851, 2004.*
  • Hayasaka D, Gritsun TS, Yoshii K, Ueki T, Goto A, Mizutani T, Kariwa H, Iwasaki T, Gould EA, Takashima I. Amino acid changes responsible for attenuation of virus neurovirulence in an infectious cDNA clone of the Oshima strain of tick-borne encephaliti・・・
    2004  [Not refereed][Not invited]
     
    Hayasaka D, Gritsun TS, Yoshii K, Ueki T, Goto A, Mizutani T, Kariwa H, Iwasaki T, Gould EA, Takashima I. Amino acid changes responsible for attenuation of virus neurovirulence in an infectious cDNA clone of the Oshima strain of tick-borne encephalitis virus. J Gen Virol. 85(Pt 4): 1007-1018, 2004.*
  • Lokugamage K, Kariwa H, Lokugamage N, Miyamoto H, Iwasa M, Hagiya T, Araki K, Tachi A, Mizutani T, Yoshimatsu K, Arikawa J, Takashima I. Genetic and antigenic characterization of the Amur virus associated with hemorrhagic fever with renal syndrome. Vir・・・
    2004  [Not refereed][Not invited]
     
    Lokugamage K, Kariwa H, Lokugamage N, Miyamoto H, Iwasa M, Hagiya T, Araki K, Tachi A, Mizutani T, Yoshimatsu K, Arikawa J, Takashima I. Genetic and antigenic characterization of the Amur virus associated with hemorrhagic fever with renal syndrome. Virus Res. 101(2): 127-134, 2004.*
  • Shirato K, Kimura T, Mizutani T, Kariwa H, Takashima I. Different chemokine expression in lethal and non-lethal murine West Nile virus infection. J Med Virol. 74(3): 507-513, 2004.*
    2004  [Not refereed][Not invited]
  • 2004  [Not refereed][Not invited]
  • Yoshii K, Konno A, Goto A, Nio J, Obara M, Ueki T, Hayasaka D, Mizutani T, Kariwa H, Takashima I. Single point mutation in tick-borne encephalitis virus prM protein induces a reduction of virus particle secretion. J Gen Virol. 85(Pt 10):3049-3058, 20・・・
    2004  [Not refereed][Not invited]
     
    Yoshii K, Konno A, Goto A, Nio J, Obara M, Ueki T, Hayasaka D, Mizutani T, Kariwa H, Takashima I. Single point mutation in tick-borne encephalitis virus prM protein induces a reduction of virus particle secretion. J Gen Virol. 85(Pt 10):3049-3058, 2004.*
  • J Arikawa, K Yoshimatsu, H Wang, H Kariwa, K Lokugamage, N Lokugamage, Takashima, I  JOURNAL OF CLINICAL VIROLOGY  28-  S28  -S28  2003/12  [Not refereed][Not invited]
  • 岩崎 琢也, 早坂 大輔, 永田 典代, 清水 博之, 小池 智, 細沼 美樹, 野本 明男, 苅和 宏明, 荒尾 雄二郎  長崎大学熱帯医学研究所共同研究報告集  14-  46  -49  2003/08
  • Mizutani, T., Kobayashi, M., Eshita, Y., Shirato, K., Kimura, T., Ako, Y., Miyoshi, H., Takasaki, T., Kurane, I., Kariwa, H., Umemura, T., and Takashima, I.:"Involvement of the JNK-like protein of the Aedes albopictus mosquito cell line, C6/36, in phag・・・
    2003  [Not refereed][Not invited]
     
    Mizutani, T., Kobayashi, M., Eshita, Y., Shirato, K., Kimura, T., Ako, Y., Miyoshi, H., Takasaki, T., Kurane, I., Kariwa, H., Umemura, T., and Takashima, I.:"Involvement of the JNK-like protein of the Aedes albopictus mosquito cell line, C6/36, in phagocytosis, endocytosis and infection of West Nile virus", Insect Molecular Biology, 12:491-499(2003)*
  • Goto, A., Hayasaka, D., Yoshii, K., Mizutani, T., Kariwa, H., and Takashima, I.:"A BHK-21 cell culture-adapted tick-borne encephalitis virus mutant is attenuated for neuroinvasiveness", Vaccine 21:4043-4051(2003)*
    2003  [Not refereed][Not invited]
  • Mizutani, T., Kobayashi, M., Eshita, Y., Inanami, O., Yamamori, T., Goto, A., Ako, Y., Miyoshi, H., Miyamoto, H., Kariwa, H., Kuwabara, M., and Takashima, I.:"Characterization of JNK-like protein derived from a mosquito cell line, C6/36", Insect Molec・・・
    2003  [Not refereed][Not invited]
     
    Mizutani, T., Kobayashi, M., Eshita, Y., Inanami, O., Yamamori, T., Goto, A., Ako, Y., Miyoshi, H., Miyamoto, H., Kariwa, H., Kuwabara, M., and Takashima, I.:"Characterization of JNK-like protein derived from a mosquito cell line, C6/36", Insect Molecular Biology, 12(1):61-66(2003)*
  • Kariwa, H., Tanabe, H., Mizutani, T., Kon, Y., Lokugamage, K., Lokugamage, N., Iwasa, M.A., Hagiya, T., Araki, K., Yoshimatsu, K., Arikawa, J., and Takashima, I.:"Synthesis of Seoul virus RNA and structural proteins in cultured cells", Archives of Viro・・・
    2003  [Not refereed][Not invited]
     
    Kariwa, H., Tanabe, H., Mizutani, T., Kon, Y., Lokugamage, K., Lokugamage, N., Iwasa, M.A., Hagiya, T., Araki, K., Yoshimatsu, K., Arikawa, J., and Takashima, I.:"Synthesis of Seoul virus RNA and structural proteins in cultured cells", Archives of Virology 148:1671-1685(2003)*
  • Lee, B.H., Yoshimatsu, K., Araki, K., Ogino, M., Okumura, M., Tsuchiya, K., Kariwa, H., and Arikawa, J.:"Detection of antibody for the serodiagnosis of hantavirus infection in different rodent species", Archives of Virology, 148:1885-1897(2003)*
    2003  [Not refereed][Not invited]
  • Shirato, K., Mizutani, T., Kariwa, H., and Takashima, I.:"Discrimination of West Nile virus and Japanese encephalitis virus strains using RT-PCR RFLP analysis", Microbiology and Immunology, 47:439-445(2003)*
    2003  [Not refereed][Not invited]
  • Miyamoto, H., Kariwa, H., Araki, K., Lokugamage, K., Hayasaka, D., Cui, B.Z., Lokugamage, N., Ivanov, L.I., Mizutani, T., Iwasa, M.A., Yoshimatsu, K., Arikawa, J., and Takashima, I.:" Serological analysis of hemorrhagic fever with renal syndrome (HFRS)・・・
    2003  [Not refereed][Not invited]
     
    Miyamoto, H., Kariwa, H., Araki, K., Lokugamage, K., Hayasaka, D., Cui, B.Z., Lokugamage, N., Ivanov, L.I., Mizutani, T., Iwasa, M.A., Yoshimatsu, K., Arikawa, J., and Takashima, I.:" Serological analysis of hemorrhagic fever with renal syndrome (HFRS) patients in Far Eastern Russia and identification of the causative hantavirus genotype", Archives of Virology, 148:1543-1556(2003)*
  • Araki, K., Yoshimatsu, K., Lee, B.H., Kariwa, H., Takashima, I., and Arikawa, J.:"Hantavirus-specific CD8(+)-T-cell responses in newborn mice persistently infected with Hantaan virus", Journal of Virology, 77:8408-8417(2003)*
    2003  [Not refereed][Not invited]
  • Lokugamage, N., Kariwa, H., Lokugamage, K., Hagiya, T., Miyamoto, H., Iwasa, M.A., Araki, K., Yoshimatsu, K., Arikawa, J., Mizutani, T., and Takashima, I.:"Development of an efficient method for recovery of Puumala and Puumala-related viruses by inocul・・・
    2003  [Not refereed][Not invited]
     
    Lokugamage, N., Kariwa, H., Lokugamage, K., Hagiya, T., Miyamoto, H., Iwasa, M.A., Araki, K., Yoshimatsu, K., Arikawa, J., Mizutani, T., and Takashima, I.:"Development of an efficient method for recovery of Puumala and Puumala-related viruses by inoculation of Mongolian gerbils", Journal of Veterinary Medical Science 65:1189-1194(2003)*
  • Yoshii, K., Hayasaka, D., Goto, A., Obara, M., Araki, K., Yoshimatsu, K., Arikawa, J., Ivanov, L., Mizutani, T., Kariwa, H., and Takashima, I.:"Enzyme-linked immunosorbent assay using recombinant antigens expressed in mammalian cells for serodiagnosis ・・・
    2003  [Not refereed][Not invited]
     
    Yoshii, K., Hayasaka, D., Goto, A., Obara, M., Araki, K., Yoshimatsu, K., Arikawa, J., Ivanov, L., Mizutani, T., Kariwa, H., and Takashima, I.:"Enzyme-linked immunosorbent assay using recombinant antigens expressed in mammalian cells for serodiagnosis of tick-borne encephalitis", Journal of Virological Methods, 108:171-179(2003)*
  • Y Yahara, Y Ohkubo, H Kariwa, Takashima, I  JOURNAL OF VETERINARY MEDICAL SCIENCE  64-  (7)  583  -588  2002/07  [Not refereed][Not invited]
     
    To evaluate the immunofluorescent antibody (IFA) test and enzyme-linked immunosorbent assay (ELISA) for detecting the porcine reproductive and respiratory syndrome virus (PRRSV) antibody, conventional pigs in PRRSV-positive and -negative commercial farms were examined. Antibody development patterns in ELISA and IFA tests were compared in 3 week old piglets experimentally infected with the PRRSV. The virus was detected from 2 days post infection (PI) and then the antibody titers and S/P ratios rose by both methods. A total of 208 serum samples were collected from 4 PRRSV-negative farms and 210 samples from PRRSV-positive farms, and were tested for the PRRSV antibody by IFA and ELISA. The titer of 64 should be set as the cut-off point in IFA for field sera. Similarly, the cut-off S/P ratio should be set at 0.4 in ELISA. A high degree of correlation was observed between antibody titers by the two methods in these 418 samples, with a correlation coefficient of 0.84. The coincidence rate between the two tests was 84.7% (354/418). In non-coincident cases, ELISA was able to detect the antibody with a low titer in the serum samples which were negative in IFA but from PRRSV positive farms. ELISA was more sensitive than IFA to detect PRRSV infected animals or farms.
  • 後藤明子, 早坂大輔, 水谷哲也, 苅和宏明, 高島郁夫  日本獣医学会学術集会講演要旨集  133rd-  2002
  • Goto, A., Hayasaka, D., Yoshii, K., Mizutani, T., Kariwa, H., Takashima, I. :"Genetic and biological comparison of tick-borne encephalitis viruses from Hokkaido and far-eastern Russia": Jpn J Vet Res, 49:297-307(2002)*
    2002  [Not refereed][Not invited]
  • Lokugamage, K., Kariwa, H., Hayasaka, D., Cui, B.Z., Iwasaki, T., Lokugamage, N., Ivanov, L.I., Volkov, V.I., Demenev, V.A., Slonova, R., Kompanets, G., Kushnaryova, T., Kurata, T., Maeda, K., Araki, K., Mizutani, T., Yoshimatsu, K., Arikawa, J., Takas・・・
    2002  [Not refereed][Not invited]
     
    Lokugamage, K., Kariwa, H., Hayasaka, D., Cui, B.Z., Iwasaki, T., Lokugamage, N., Ivanov, L.I., Volkov, V.I., Demenev, V.A., Slonova, R., Kompanets, G., Kushnaryova, T., Kurata, T., Maeda, K., Araki, K., Mizutani, T., Yoshimatsu, K., Arikawa, J., Takashima, I.:"Genetic characterization of hantaviruses transmitted by the Korean field mouse (Apodemus peninsulae), Far East Russia"
    Emerg Infect Dis, 8:768-776(2002)*
  • H Wang, K Yoshimatsu, H Ebihara, M Ogino, K Araki, H Kariwa, ZX Wang, ZZ Luo, DX Li, CS Hang, J Arikawa  VIROLOGY  278-  (2)  332  -345  2000/12  [Not refereed][Not invited]
     
    The antigenic and genetic properties of 46 hantaviruses from China, 13 from patients, 23 from rodents, and 10 from unknown hosts, were compared with those of other hantaviruses. The viruses were classified as either Hantaan (HTN) or Seoul (SEO) viruses. A phylogenetic analysis of the partial M (300 bp) and S (around 485 bp) genomes of HTN viruses identified nine distinct genetic subtypes, one consisting of isolates from Korea. The SEC viruses were divided into five genetic subtypes, although they had less variability than the HTN subtypes. There was a correlation between the subtype and province of origin for four subtypes of HTN viruses, confirming geographical clustering. Hantaan virus NC167 isolated from Niviventer confucianus and SEO virus Gou3 isolated from Rattus rattus were the basal clades in each virus. The phylogenetic trees constructed from the entire S and M segments suggested that NC167 was introduced to N. confucianus in a host-switching event. The reactivity of a panel of 35 monoclonal antibodies was almost exactly the same in NC167 and a representative HTN virus and in Gou3 and a representative SEC virus. However. there was a one-way cross-neutralization between them. These results confirm the varied nature of Murinae-associated hantaviruses in China. (C) 2000 Academic Press.
  • H Ebihara, K Yoshimatsu, M Ogino, K Araki, Y Ami, H Kariwa, Takashima, I, DX Li, J Arikawa  JOURNAL OF VIROLOGY  74-  (19)  9245  -9255  2000/10  [Not refereed][Not invited]
     
    Two Hantaan virus strains, clone 1 (cl-1), which is virulent in newborn mice, and its attenuated mutant (mul1E10), were used to examine the pathogenesis of Hantaan virus infection in a mouse model and identify virus factors relating to virulence. After subcutaneous inoculation of newborn BALB/c mice, cl-1 caused fatal disease with high viral multiplication in peripheral organs, but mul1E10 produced nonfatal infection with a low level of virus multiplication. Intracerebral inoculation of either strain caused fatal disease. Histopathological changes in the dead animals were prominent in the brain, indicating that the brain is the target organ and produces the fatal outcome. These results indicate that mul1E10 has a generally less virulent phenotype, and because of decreased multiplication in peripheral tissues, neuroinvasiveness is also decreased. An experiment with genetic reassortant viruses showed that in newborn mice the M segment is the most related to virulence and the L segment is partly related. Sequence comparison detected a single deduced amino acid change (cl-l Ile to mul1E10 Thr) at amino acid number 515 in glycoprotein G1. One nucleotide change, but no amino acid substitution, was observed in the noncoding region of the L segment. In mouse brain microvascular endothelial cells in vitro, viruses possessing a cl-1-derived M segment grew more rapidly than viruses containing a mul1E10 derived M segment. These results suggest that the single amino acid change in the glycoprotein alters peripheral growth, which affects invasion of the central nervous system in mice.
  • 後藤明子, 早坂大輔, 水谷哲也, 苅和宏明, 高島郁夫  日本獣医学会学術集会講演要旨集  129th-  2000
  • Wang, H., Yoshimatsu, K., Ebihara, H., Ogino, M., Araki, K., Kariwa, H., Wang, Z., Luo, Z., Li, D., Hang, C. and Arikawa, J.: "Genetic diversity of hantaviruses isolated in china and characterization of novel hantaviruses isolated from Niviventer confu・・・
    2000  [Not refereed][Not invited]
     
    Wang, H., Yoshimatsu, K., Ebihara, H., Ogino, M., Araki, K., Kariwa, H., Wang, Z., Luo, Z., Li, D., Hang, C. and Arikawa, J.: "Genetic diversity of hantaviruses isolated in china and characterization of novel hantaviruses isolated from Niviventer confucianus and Rattus rattus", Virology, 278:332-345(2000)*
  • Kariwa, H., Yoshimatsu, K., Araki, K., Chayama, K., Kumada, H., Ogino, M., Ebihara, H., Murphy, M.E., Mizutani, T., Takashima, I. and Arikawa, J.: "Detection of hantaviral antibodies among patients with hepatitis of unknown etiology in Japan", Microbio・・・
    2000  [Not refereed][Not invited]
     
    Kariwa, H., Yoshimatsu, K., Araki, K., Chayama, K., Kumada, H., Ogino, M., Ebihara, H., Murphy, M.E., Mizutani, T., Takashima, I. and Arikawa, J.:
    "Detection of hantaviral antibodies among patients with hepatitis of unknown etiology in Japan", Microbiology and Immunology, 44:357-362(2000)*
  • Murphy, M.E., Kariwa, H., Mizutani, T., Yoshimatsu, K., Arikawa, J. and Takashima I.: "In vitro antiviral activity of lactoferrin and ribavirin upon hantavirus", Archives of Virology, 145:1571-1582(2000)*
    2000  [Not refereed][Not invited]
  • Tetsuya Mizutani, Hisae Inagaki, Mitsuhiro Tada, Daisuke Hayasaka, Michael Murphy, Toshiyoshi Fujiwara, Jun-Ichi Hamada, Hiroaki Kariwa, Ikuo Takashima  Microbiology and Immunology  44-  (7)  597  -603  2000  [Not refereed][Not invited]
     
    The transcriptional mechanism of Borna disease virus (BDV) has been poorly understood. We have analyzed transcription of the virus upon various stimuli in Madin-Darby canine kidney cells which were persistently infected by BDV (MDCK/BDV). Treatment with actinomycin D (ActD) increased the level of BDV RNA, shifting the size of RNA from 1.9 kb to 2.3 kb beginning 5 hr after the treatment. To understand the mechanism of tills unique modulation of BDV RNA, we conducted several experiments. The RNA increase occurred at the stage in which synthesis of cellular intrinsic mRNA was intact, suggesting BDV does not compete with cellular transcriptional machinery for intrinsic RNA polymerase II. The BDV transcription was also enhanced by cycloheximide treatment, indicating that newly synthesized viral or cellular proteins are not necessary for viral transcription. However, a shift in the RNA size was not observed for cycloheximide-induced BDV RNA. The increase in viral transcription persisted during the cellular apoptotic process consequent to p53 gene accumulation beginning 1 hr after ActD treatment. Caspase inhibitors Z-VAD and DEVD-CHO repressed the apoptotic process but failed to block the increase in BDV transcription. In addition, adenovirus-mediated transduction of wild-type p53 did not alter the BDV transcription, indicating that the increase in BDV transcription was independent of the p53-mediated apoptotic process. Other various stimuli that evoke cellular signal transductions failed to alter BDV transcription. Agents inhibitory to topoisomerase except adriamycin failed to enhance BDV transcription, indicating that the increase in BDV transcription is not mediated by an inhibitory action to the topoisomerase II of ActD. Adriamycin showed an increase and size-shift of BDV RNA similar to ActD. These results suggest that intercalation of the viral genome itself with ActD is related to the stabilization of viral RNA and alteration of RNA size rather titan secondary host cell changes.
  • Komoro, K., Hayasaka, D., Mizutani, T., Kariwa, H. and Takashima, I.: "Characterization of monoclonal antibodies against Hokkaido strain tick-borne encephalitis virus", Microbiology and Immunology,44:533-536(2000)*
    2000  [Not refereed][Not invited]
  • H Kariwa, K Yoshimatsu, J Sawabe, E Yokota, J Arikawa, Takashima, I, H Fukushima, A Lundkvist, FN Shubin, LM Isachkova, RA Slonova, GN Leonova, N Hashimoto  VIRUS RESEARCH  59-  (2)  219  -228  1999/02  [Not refereed][Not invited]
     
    Seroepizootiologic surveys among wild rodents were carried out in Japan and Far East Russia in 1995 and 1996. Seropositive animals were only identified in Clethrionomys rufocanus (23/134) in Hokkaido, Japan. On the other hand, seropositives were identified in C. rufocanus (1/8), Apodemus argrarius (2/66), Apodemus spp. (2/26) and Microtus fortis (3/22) in Vladivostok, Far East Russia. Total RNA was isolated from lungs of seropositive animals and the S genome segments were amplified by PCR, cloned and sequenced. The S and M genomes of hantavirus, derived from Japanese C. rufocanus (Tobetsu genotype), were most closely related with Puumala viruses (76-79% nucleotide and 95% amino acid identities for S genome, 70-78% nucleotide and 87-92% amino acid identities for M genome). The recombinant nucleocapsid protein of Tobetsu genotype was antigenically quite similar with that of Sotkamo. These suggest that the virus endemic in Japanese C. rufocanus belongs to Puumala virus. Phylogenetic analysis indicates that the genotype forms a distinct lineage within Puumala viruses. Partial S segment (1-1251 nt), derived from seropositive M. fortis in Vladivostok, was sequenced and analyzed. The S genome segment, which was designated Vladivostok genotype, was most closely related with Khabarovsk virus (79% nucleotide and 90% amino acid identities) which was isolated from M. fortis. (C) 1999 Elsevier Science B.V. All rights reserved.
  • Kariwa H, Yoshimatsu K, Sawabe J, Yokota E, Arikawa J, Takashima I, Fukushima H, Lundkvist A, Shubin FN, Isachkova LM, Slonova RA, Leonova GN, Hashimoto N.:"Genetic diversities of hantaviruses among rodents in Hokkaido, Japan and Far East Russia", Viru・・・
    1999  [Not refereed][Not invited]
     
    Kariwa H, Yoshimatsu K, Sawabe J, Yokota E, Arikawa J, Takashima I, Fukushima H, Lundkvist A, Shubin FN, Isachkova LM, Slonova RA, Leonova GN, Hashimoto N.:"Genetic diversities of hantaviruses among rodents in Hokkaido, Japan and Far East Russia", Virus Res., 59(2):219-28 (1999)*
  • Hayasaka D, Suzuki Y, Kariwa H, Ivanov L, Volkov V, Demenev V, Mizutani T, Gojobori T, Takashima I.:"Phylogenetic and virulence analysis of tick-borne encephalitis viruses from Japan and far-Eastern Russia", J Gen Virol., 80 (12):3127-3135 (1999)*
    1999  [Not refereed][Not invited]
  • Mizutani T, Inagaki H, Hayasaka D, Kariwa H, Takashima I.:"Enhancement of Borna disease virus transcription in persistently infected cells by serum starvation", J Vet Med Sci., 61(7):831-834 (1999)*
    1999  [Not refereed][Not invited]
  • Chiba N, Osada M, Komoro K, Mizutani T, Kariwa H, Takashima I.:"Protection against tick-borne encephalitis virus isolated in Japan by active and passive immunization", Vaccine., 17(11-12):1532-1539 (1999)*
    1999  [Not refereed][Not invited]
  • T. Mizutani, H. Inagaki, D. Hayasaka, S. Shuto, N. Minakawa, A. Matsuda, H. Kariwa, I. Takashima  Archives of Virology  144-  (10)  1937  -1946  1999  [Not refereed][Not invited]
     
    Regulation of viral RNA levels in infected cells is considered important in the investigation of viral transcription and replication. Amounts of Borna disease virus (BDV) RNAs were increased in confluent persistently BDV-infected MDCK cells (MDCK/BDV) cells, while maintained at low levels in growing cells. The amount of 1.9-kb RNA without cap formation and polyadenylation at the 5' and 3' ends respectively were remarkably increased (200% per day) in confluent MDCK/BDV cells. Both the full-length genomic and anti-genomic RNAs were increased accompanied by 1.9-kb RNA, suggesting the transcription of the 1.9-kb RNA was important for replication of BDV. Ribavirin has an inhibitory effect on replication and transcription of BDV at concentrations from 1 to 10 μg/ml [Mizutani T et al., Arch Virol (1998)143:2039-2044]. BDV transcripts were decreased with ribavirin treatment and increased after its removal which indicated that ribavirin has a reversible inhibitory effect on BDV transcription. Furthermore, BDV transcription was also decreased by two agents, RMNPA and EICAR, which selectively inhibit enzyme activity related to cap formation at the 5' end of mRNA. On the contrary, when the growing MDCK/BDV cells were treated with actinomycin D, transcripts of BDV RNA were increased for 24 h. These agents and culture conditions in this study were found to be useful tools for up- and down-regulation of BDV transcription in persistently BDV-infected cells.
  • Mizutani T, Nishino Y, Kariwa H, Takashima I.:"Reverse transcription-nested polymerase chain reaction for detecting p40 RNA of Borna disease virus, without risk of plasmid contamination", J Vet Med Sci., 61(1):77-80 (1999)*
    1999  [Not refereed][Not invited]
  • Mizutani T, Ogino M, Nishino Y, Kimura T, Inagaki H, Hayasaka D, Kariwa H, Takashima I.:"Single-step reverse transcriptase-polymerase chain reaction for detection of Borna disease virus RNA in vitro and in vivo", Jpn J Vet Res., 46(4):165-169 (1999)*
    1999  [Not refereed][Not invited]
  • Tsujimura K, Mizutani T, Kariwa H, Yoshimatsu K, Ogino M, Morii Y, Inagaki H, Arikawa J, Takashima I.:"A serosurvey of Borna disease virus infection in wild rats by a capture ELISA", J Vet Med Sci., 61(2):113-7 (1999)*
    1999  [Not refereed][Not invited]
  • Chiba N, Iwasaki T, Mizutani T, Kariwa H, Kurata T, Takashima I.:"Pathogenicity of tick-borne encephalitis virus isolated in Hokkaido, Japan in mouse model", Vaccine., 17(7-8):779-787 (1999)*
    1999  [Not refereed][Not invited]
  • MIZUTANI Tetsuya, NISHINO Yoshii, KARIWA Hiroaki, TAKASHIMA Ikuo  日本分子生物学会年会プログラム・講演要旨集  21-  319  -319  1998/12/01
  • 苅和 宏明, 高島 郁夫  小児科臨床  51-  (12)  2547  -2550  1998/12
  • H Kariwa, M Fujiki, K Yoshimatsu, J Arikawa, Takashima, I, N Hashimoto  ARCHIVES OF VIROLOGY  143-  (1)  15  -24  1998  [Not refereed][Not invited]
     
    To understand the mode of transmission of Seoul type hantavirus in Wistar rats, we examined the shedding of the virus and antibody production in infected rats. When 1-day-old rats were inoculated with the KI-83-262 strain of Seoul virus, S segment of the viral genome was detected in lungs, clots, urine, saliva, submaxillary glands, rectums, and kidneys by nested reverse transcriptase PCR. On the other hand, when 8-week-old rats were infected with the virus, viral genome was detected only in the lungs and rectum. In newborn rats intranasally administered urine from infected newborn rats, four of six rats shed the virus into their urine. In addition, three of eight rats kept in the same cage with infected animals also shed the virus into urine. Moreover, the virus genome was detected in the urine of urban rats (Rattus norvegicus) in an enzootic focus. These findings suggest that the urine containing virus from infected rats is an actual source of the Seoul virus infection.
  • ＊Kariwa, H., Fujiki, M., Yoshimatsu, K., Arikawa, J., Takashima, I., Hashimoto, N. "Urine-associated horizontal transmission of Seoul virus among rats", Archives of Virology, 143: 15-24 (1998）*
    1998  [Not refereed][Not invited]
  • Morii, M., Yoshimatsu, K., Arikawa, J., Zhou, G, Kariwa, H., Takashima, I. "Antigenic characterization of Hantaan and Seoul virus nucleocapsid proteins expressed by recombinant baculovirus: application of a truncated protein, lacking an antigenic regio・・・
    1998  [Not refereed][Not invited]
     
    Morii, M., Yoshimatsu, K., Arikawa, J., Zhou, G, Kariwa, H., Takashima, I. "Antigenic characterization of Hantaan and Seoul virus nucleocapsid proteins expressed by recombinant baculovirus: application of a truncated protein, lacking an antigenic region common to the two viruses, as a serotyping antigen", Journal of Clinical Microbiology, 36: 2514-2521 (1998) *
  • TAKASHIMA Ikuo, KARIWA Hiroaki, MIZUTANI Tetsuya  Japanese journal of veterinary research  45-  (3)  176  -177  1997/11/28
  • 苅和 宏明  臨床と微生物 = Clinical microbiology  24-  (5)  557  -565  1997/09/25
  • Takashima, I, K Morita, M Chiba, D Hayasaka, T Sato, C Takezawa, A Igarashi, H Kariwa, K Yoshimatsu, J Arikawa, N Hashimoto  JOURNAL OF CLINICAL MICROBIOLOGY  35-  (8)  1943  -1947  1997/08  [Not refereed][Not invited]
     
    A case of tick-borne encephalitis (TEE) has not been reported for many years in Japan, although a serological survey of sera from domestic animals suggested the presence of TEE foci in Hokkaido, the northern island of Japan. Studies were conducted to prove the presence of an endemic focus of TEE virus in Japan by means of serology and virus isolation. In October 1993 in Hokkaido, a severe case of encephalitis in a dairy farmer's nife was diagnosed as TEE. Serological examination of paired serum specimens showed a rise in the neutralization antibody titer to Russian spring summer encephalitis virus. A seroepizootiological survey of dogs showed that the TEE-related virus was prevalent in the area. Three virus isolates were obtained from the blood of sentinel dogs, and antigenic analysis grouped the isolates into TEE-related viruses. Sequence analysis of the envelope protein gene identified one of the isolates as being of the same subtype as the Russian spring summer encephalitis (Far Eastern TEE) virus. The results provide evidence that TEE is endemic in a certain area of Japan.
  • Takashima, I., Morita, K., Chiba, M., Hayasaka, D., Sato, T., Takezawa, C., Igarashi, A., Kariwa, H., Yoshimatsu, K., Arikawa, J. and Hashimoto, N. : "A case of tick-borne encephalitis in Japan and isolation of the the virus", J. Clin. Microbiol., 35 :・・・
    1997  [Not refereed][Not invited]
     
    Takashima, I., Morita, K., Chiba, M., Hayasaka, D., Sato, T., Takezawa, C., Igarashi, A., Kariwa, H., Yoshimatsu, K., Arikawa, J. and Hashimoto, N. : "A case of tick-borne encephalitis in Japan and isolation of the the virus", J. Clin. Microbiol., 35 : 1943-1947 (1997)＊
  • Ennis, F. A., Cruz, J., Spiropoulou, C. F., Waite, D., Peters, C. J., Nichol, S. T., Kariwa, H. and Koster, F. T. : "Hantavirus pulmonary syndrome : CD8＋ and CD4＋ cytotoxic T lymphocytes to epitopes on Sin Nombre virus nucleocapsid protein isolated dur・・・
    1997  [Not refereed][Not invited]
     
    Ennis, F. A., Cruz, J., Spiropoulou, C. F., Waite, D., Peters, C. J., Nichol, S. T., Kariwa, H. and Koster, F. T. : "Hantavirus pulmonary syndrome : CD8＋ and CD4＋ cytotoxic T lymphocytes to epitopes on Sin Nombre virus nucleocapsid protein isolated during acute illness", Virology, 238 : 380-390 (1997)＊
  • A Ito, M Okamoto, H Kariwa, T Ishiguro, A Hashimoto, M Nakao  JOURNAL OF HELMINTHOLOGY  70-  (4)  355  -357  1996/12  [Not refereed][Not invited]
     
    Two Norway rats, Rattus norvegicus, were found to be naturally infected with Echinococcus multilocularis in Japan. One of them was simultaneously infected with at least three different sized metacestodes of Taenia taeniaeformis. These two R. norvegicus rats and another R. norvegicus naturally infected with T. taeniaeformis and Capillaria hepatica were examined to see if they showed any antibody responses against these two cestode parasites with the view to obtaining more information on the importance of rats as the intermediate host for E. multilocularis. These R. norvegicus showed very poor antibody responses against the two cestode species, although the Wistar rats, R. rattus, experimentally infected with a single smaller sized metacestode of T. taeniaeformis showed stronger responses not only against T. taeniaeformis but also against E. multilocularis. Therefore the three R. norvegicus naturally infected with E. multilocularis and/or T. taeniaeformis demonstrated virtually no immune response, at least against these cestodes.
  • K Yoshimatsu, J Arikawa, M Tamura, R Yoshida, A Lundkvist, B Niklasson, H Kariwa, Azuma, I  JOURNAL OF GENERAL VIROLOGY  77-  695  -704  1996/04  [Not refereed][Not invited]
     
    We characterized the antigenic sites on the nucleocapsid protein (NP) of Hantaan virus (HTN) using 10 monoclonal antibodies (MAbs). At least seven antigenic sites were revealed by a competitive binding assay and divided into three partially overlapping antigenic regions (I, II and III). Regions I [amino acids (aa) 1-103], II (aa 104-204) and III (aa 205-402) were mapped on NP by examinincr the reactivity of truncated gene products. Those that corresponded to region I reacted with immune mouse serum, indicating that the region contained major linear epitopes as reported with Four corners virus (FCV) and Puumala virus (PUU) NP. At least one MAb to each region inhibited viral growth when they were introduced into cells by scrape-loading. In addition, they conferred protection from a lethal HTN challenge to newborn mice. A PEPSCAN assay localized the epitope of MAb E5/G6 between aa 166-175. Since E5/G6, which had the highest inhibitory effect both in cells and in mice, showed no virus neutralization activity by ordinary neutralization test, this region is suggested to be important for the virus growth after entry into the cells.
  • TAKASHIMA Ikuo, IMAI Yumi, ITOH Norihiko, KARIWA Hiroaki, HASHIMOTO Nobuo  Microbiol Immunol  40-  (1)  21  -26  1996/01/20
  • Kumiko Yoshimatsu, Jiro Arikawa, Mizuho Tamura, Ryu Yoshida, Lundkvist, B. Niklasson, H. Kariwa, Ichiro Azuma.  Collected papers from the Institute of Immunological Science Hokkaido University  19-  143  -152  1996
  • K Yoshimatsu, J Arikawa, H Li, H Kariwa, N Hashimoto  JOURNAL OF VETERINARY MEDICAL SCIENCE  58-  (1)  71  -74  1996/01  [Not refereed][Not invited]
     
    Recombinant Hantaan virus nucleocapsid protein expressed in silkworm larvae was applied as a serological diagnostic antigen in Western blots (WE) of human sera. The sensitivity of this method was similar to that of the IFA test. Hemorrhagic fever with renal syndrome (HFRS) and nephropathia epidemica diagnosed by their cross-reactivity in WE. The specificity of this method was higher than that of IFA test because the background was low. Sera that exhibited high background staining in the IFA test were readily diagnosed with this method. We recommended WE using recombinant Hantaan virus nucleocapsid antigen as a confirmatory procedure for the serodiagnosis of hantavirus.
  • I. Takashima, M. Hiyoshi, H. Kariwa, R. Mukaiya and N. Hashimoto : "Experimental Chlamydia psittaci infection of Japanese quail", Microbiol. Immunol., 40 : 265-701 (1996)＊
    1996  [Not refereed][Not invited]
  • I. Takashima, Y. Imai, N. Itoh, H. Kariwa and N. Hashimoto : "Polymerase chain reaction for the detection of Chlamydia psittaci in the feces of budgerigars", Microb. Immunol., 40 : 21-26 (1996)＊
    1996  [Not refereed][Not invited]
  • H. Kariwa, M. Kimura, S. Yoshizumi, J. Arikawa, K. Yoshimatsu, I. Takashima and N. Hashimoto : "Different modes of Seoul virus infection : persistency in newborn rats and transiency in adult rats", Arch. Virol., 141 : 2327-2338 (1996)＊
    1996  [Not refereed][Not invited]
  • Yoshimatsu Kumiko, Arikawa Jiro, Yoshida Ryu, Li Hong, Yoo Yong-Chun, Kariwa Hiroaki, Hashimoto Nobuo, Kakinuma Mitusaki, Nobunaga Toshima, Azuma Ichiro  Collected papers from the Institute of Immunological Science Hokkaido University  18-  358  -363  1995
  • Kariwa Hiroaki, Kamimura Mizuho, Arikawa Jiro, Yoshimatsu Kumiko, Takashima Ikuo, Hashimoto Nobuo  Collected papers from the Institute of Immunological Science Hokkaido University  18-  345  -351  1995
  • Kariwa Hiroaki, Yoshizumi Shima, Arikawa Jiro, Yoshimatsu Kumiko, Takahashi Kenichi, Takashima Ikuo, Hashimoto Nobuo  Collected papers from the Institute of Immunological Science Hokkaido University  18-  352  -357  1995
  • Kariwa Hiroaki, Arikawa Jiro, Takashima Ikuo, Isegawa Yuji, Yamanishi Koichi, Hashimoto Nobuo  Collected papers from the Institute of Immunological Science Hokkaido University  17-  427  -436  1994
  • Kariwa Hiroaki, Isegawa Yuji, Arikawa Jiro, Takashima Ikuo, Ueda Shigeharu, Yamanishi Koichi, Hashimoto Nobuo  Collected papers from the Institute of Immunological Science Hokkaido University  17-  437  -448  1994
  • Arikawa Jiro, Ito Mikiko, Yao Jian-Sheng, Kariwa Hiroaki, Takashima Ikuo, Hashimoto Nobuo  Collected papers from the Institute of Immunological Science Hokkaido University  17-  421  -426  1994
  • MIYAMOTO Chikako, TAKASHIMA Ikuo, KARAIWA Hiroaki, SUGIURA Takeo, KAMADA Masanobu, HASHIMOTO Nobuo  The journal of veterinary medical science  55-  (2)  333  -335  1993/04/15  
    To investigate the overall prevalance of chlamydial infections in light (i.e. non-draught) horses in Japan, 599 sera obtained from 12 1ocalities in 1991 were tested for complement fixation antibodies. The mean antibody positive rates of the all sera were 15.2% (91/599) and the regional positive rates were higher in Honshu (19.1%, 48/251) and Kyushu (20.0%, 20/100) than in Hokkaido (9.3%, 23/248). In Honshu, the highest rate (56.0%, 28/50) was observed in Utsunomiya. Analysis of the positive rate in different age groups showed that the 2-5 years age-group had the highest prevalance of chlamydial infections. This indicates that chlamydial infection is prevalant in light horses in Japan.
  • Yoshimatsu Kumiko, Arikawa Jiro, Kariwa Hiroaki  Collected papers from the Institute of Immunological Science Hokkaido University  16-  425  -428  1993
  • KARIWA Hiroaki  Japanese journal of veterinary research  34-  (2)  136  -136  1986/04/30

Books etc

  • Animal viruses
    Transworld Research Network 2010
  • SARS
    Transworld Research Network 2006
  • Hantaviruses and Hantavirus infections
    Times New Roman 2003

Association Memberships

  • 人と動物の共通感染症研究会   獣医疫学会   日本ウイルス学会   日本獣医学会   日本獣医公衆衛生学会   The Japan Society of Veterinary Epidemiology   The Japanese Society for Virology   The Japanese Society of Veterinary Science   The Japanese Society of Veterinary Public Health   

Research Projects

  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2024/04 -2027/03 
    Author : 苅和 宏明, 小林 進太郎
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2013/04 -2017/03 
    Author : KARIWA Hiroaki
     
    In this study, simple diagnostic methods were developed for zoonoses, such as hantavirus infections, tick-borne encephalitis, and West Nile fever, which are severe and fatal diseases, and are considered as major problems in many countries. ELISA and immunochromatography were developed to detect anti-hantavirus antibodies in various rodents. ELISA systems using viral-like particles (SPs) of tick-borne encephalitis virus conjunctive with IgG and Strep-tag were established. A stable reverse genetics system for West Nile virus was developed by using homologous recombination.
  • 近隣地域からの侵入が危惧されるわが国にない感染症の発生予防に関する研究
    厚生労働省：厚生労働科学研究費補助金
    Date (from‐to) : 2013/04 -2016/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    Date (from‐to) : 2012/04 -2014/03 
    Author : YOSHII KENTARO, KARIWA Hiroaki
     
    Flaviviruses include many clinically important zoonotic pathogens, and some of them cause severe encephalitis in humans and domestic animals. In study, we showed that congenic mice expressing intact Oas1b can be applied for detailed analysis of pathogenicity of flavivirus encephalitis. Furthermore, we revealed that mutations which arose during adaptation in mammals increased the virulence of tick-borne flaviviruses.
  • 海外からの侵入が危惧される野生鳥獣媒介性感染症の疫学、診断・予防法等に関する研究
    厚生労働省：厚生労働科学研究費補助金
    Date (from‐to) : 2010/04 -2013/03 
    Author : 苅和 宏明
  • わが国とアメリカ大陸のウイルス性人獣共通感染症の流行阻止のための研究
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 2009/04 -2013/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2009 -2012 
    Author : KARIWA Hiroaki, ARIKAWA Jiro, YOSHII Kentaro, MORIMATSU Kumiko
     
    Three novel hantaviruses were detected in Mexican rodents. The antibody detection method for various hantavirus infections was developed. Five of six monoclonal antibodies to nucleocapsid protein (NP) of Mexican hantavirus were broadly reacted with NPs of rodent-borne hantaviruses. Glycosylation of West Nile virus E protein made great influence in the pathogenesis in chicks infected with West Nile virus.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    Date (from‐to) : 2010 -2011 
    Author : YOSHII Kentaro, TAKASHIMA Ikuo, KARIWA Hiroaki, AGUI Takashi
     
    The interferon-inducible 2'-5'-oligoadenylate synthetases(OAS) play important roles in the antiviral activity against RNA virus infection. The murine isoform Oas1b gene has been identified as a critical determinant for genetic susceptibility to flavivirus infection. In this study, we analyzed the mechanism of the flavivirus-specific antiviral activity of Oas1b, and indicated that OAS plays crucial roles in the pathogenesis of flavivirus.
  • 国内で発生のないベクター媒介性感染症の疫学診断法等の研究
    厚生労働省：厚生労働科学研究費補助金
    Date (from‐to) : 2007/04 -2010/03 
    Author : 苅和 宏明
  • 日本に侵入する危険性の高い北米産ウイルス性人獣共通感染症の疫学的研究
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 2004/04 -2008/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2006 -2008 
    Author : ARIKAWA Jiro, MORIMATSU Kumiko, ENDO Rika, KARIWA Hiroaki
     
    ハンタウイルスは持続感染齧歯類が感染源となる人獣共通感染症でヒトに腎症候性出血熱やハンタウイルス肺症候群という重篤な疾病を引き起こす。齧歯類は血中に高い中和抗体を保有しつつ不顕性にウイルスを排泄し続けるというきわめて特徴的な持続感染を成立させている。本研究では齧歯類におけるウイルス特異的CTL抑制を中心とする免疫抑制を介したハンタウイルス持続感染成立機構の詳細を明らかにすることを目的とする。
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2005 -2008 
    Author : TAKASHIMA Ikuo, KARIWA Hiroaki, MAEDA Akihiko, ARIKAWA Jiro
     
    近年、国内外で問題となっているウイルス性人獣共通感染症のうち、侵入または流行の危険性があり、重篤に経過し致死率が高いウエストナイル熱、ダニ媒介性脳炎およびハンタウイルス感染症について診断法を開発し、疫学調査を実施し、分離ウイルスの性状解析を行った。 ウエストナイルウイルスと日本脳炎ウイルスの遺伝子鑑別診断法としてリアルタイムPCR法を開発した。さらに準ウイルス粒子とウイルス様粒子を用いた血清学的な鑑別診断法を開発した。極東ロシアの野鳥の中和抗体を測定したところ、91羽中15羽(16.5%)にウエストナイル特異的な中和抗体が検出されたことから、極東ロシアの野鳥間にウエストナイルウイルスの流行していることが示唆された。 ダニ媒介性脳炎については準ウイルス粒子を用いたヒトおよび野ネズミ用の抗体検出ELISA を開発した。本ELISAを用いて国内各地の野ネズミ血清について抗体調査を実施したところ、島根県の野ネズミ58検体中2検体がダニ媒介性脳炎ウイルス特異抗体陽性となり、新しいウイルス汚染地が特定された。 ハンタウイルス感染症では、ウイルス核タンパクを対象にしたヒトおよび野ネズミの抗体検出ELISA および抗原検出ELISAを開発した。この抗体検出ELISAを用いてタイのレプトスピラ感染症を疑われた患者に、ハンタウイルス抗体陽性例を検出したため、ハンタウイルス感染症と症状の関連が示唆された。ロシアのボルガ川流域のサマラ市において、野ネズミの疫学調査を行い、流行中のウイルスはPuumala型のハンタウイルスであることを明らかにした。北海道の中川町と当別町においてエゾヤチネズミの疫学調査を行い、ハンタウイルスの野ネズミ集団内では、オスがメスよりも有意に高い感染率を示すことを明らかにした。
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2004 -2007 
    Author : KARIWA Hiroaki, TAKASHIMA Ikuo, ARIKAWA Jiro, YOSHIMATSU Kumiko
     
    In this study, new diagnostic methods were developed and the epidemiological surveys were carried out on West Nile fever and hantavirus infections which are potentially introduced into Japan. 1) Development of diagnostic methods for West Nile fever: To establish the surveillance system to West Nile virus introduction to Japan, serological diagnostic methods for anti-West Nile virus antibodies were developed. The newly developed methods were the micro-neutralization test and inhibition ELISA. 2) Epidemiological study of West Nile fever in wild birds in Far East Russia: Total RNA was extracted from kidneys of 98 birds captured in Far East Russia and West Nile virus RNA was tried to detect by RT-PCR. Although no West Nile virus RNA was detected, neutralizing antibodies to West Nile virus were detected in 15 bird sera out of 91 samples. Therefore, it is suggested that West Nile virus is circulating among wild birds in Far East Russia. Since a lot of wild birds migrate from Far East Russia to Japan, reinforcement of control measures to West Nile fever is highly required. 3) Epidemiological study of hantavirus infections among rodents in Mexico: Virus genome detection method for hantaviruses existing in North America was developed by RT-PCR. Total RNA was extracted from lungs of 213 rodents captured in Mexico and hantavirus genome was tried to detect by RT-PCR. Among 213 samples, hantavirus RNAs were detected from 21 samples. Among these 21 virus-RNA positive rodents, 19 animals had anti-hantavirus antibodies. Therefore, it was revealed that hantaviruses are circulating among rodents in Mexico where the information of hantavirus infection is extremely limited.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2005 -2006 
    Author : INANAMI Osamu, HORIUCHI Motohiro, KARIWA Hiroaki, INABA Mustumi, KUWABARA Mikinori
     
    We examined the influence of D177N (178N in humans) mutation on the conformational stability of the S2 region of moPrPc with varying pHs by using the SDSL-ESR technique. We prepared moPrPc mutants that reacted with methane thiosulfonate spin-probes (Y161R1 and Y161R1/D177N). The ESR spectrum of D177N at pH 7.5 was narrower than that of Y161R1, referred to as WT^*. The ESR spectrum of D177N did not change when pH in the solution decreased from 7.5 to 4.0.These results suggested that the disappearance of a salt bridge (D177-R163) induced the increase in the instability of S2 region. The values of 1/ H of the central component (Mi=0) in the ESR spectrum obtained from WT^* remained constant from pH 7.5 to pH 6.5, whereas an abrupt increase of 1/Ho occurred when the pH in the solution decreased to under 6.0. These findings indicated that the conformational transition from a rigid structure to a flexible structure existed at between pH 6.5 and pH 6.0. Moreover, the line shape of the ESR spectrum obtained from H176S neighboring the salt bridge linked to the S2 region was narrower than that of WT^* at pH 7.5. When the pH in the solution decreased from 7.5 to 4.0, the change in the spectrum of H176S was small. These results indicate that the protonation of H 176 is strongly associated with the stability of S2 region. These findings are important for understanding the mechanism by which the disruption of the salt bridge in the S2 region forms the pathogenic PrP_Sc structure in hereditary Creutzfeldt-Jacob disease and fatal familial insomnia.
  • 日本と極東ロシアの野生げっ歯類を病原巣動物とする人獣共通感染症の比較疫学的研究
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 2001/04 -2004/03 
    Author : 苅和 宏明
  • わが国のげっ歯類を病原巣動物とするウイルス性人獣共通感染症の疫学的研究
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 2001/04 -2004/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2003 -2004 
    Author : MIZUTANI Tetsuya, ESHITA Yuki, KARIWA Hiroaki, KURANE Ichiro
     
    The purpose of this research is establishment the method of controlling mosquito's growth by clarifying biological functions of JNK, and development of a new insecticide based on this fundamental research. The following were clarified from the research in 2003 and 2004. 1.It was succeeded in the obstruction of growth by exposing a JNK inhibitor (SP600125) to first instar larvae of Aedes albopictus In mosquito cultured cell, JNK was confirmed to have a function of anti-apoptosis. 2.JNK was observed the activation by adding Lipopolysaccharide(LPS) to mosquito cells, and a novel gene, which should code anti-bacterial peptide, was discovered from the cells. 3.The transfection method of siRNA was examined for evaluating the function of JNK. Although inicroinjection siRNA against JNK to third instar larvae lead to decrease growth of mosquito, it was impossible to handle microinjection method to a lot of larvas. Then, we tried to improve the method of siRNA using reagents for transfection. However, we could not obtain superior to the microinjection method. 4.First instar larvae was bred in the culture medium containing potent insect chitinase inhibitors of fungal origin, and the growth was obstructed by two kinds of culture medium. The gene that codes the inhibitors is now under identification. In this research, we clarified that JNK plays important roles in mosquito. Moreover, potent inhibitors of chitinase are useful for inhibition growth of mosquito.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2002 -2004 
    Author : TAKASHIMA Ikuo, KARIWA Hiroaki, MORITA Koichi, TADANO Masayuki, TAKEGAMI Tsutomu, ESHITA Yuki
     
    In order to prevent the outbreaks of flavivirus infections, we developed the diagnostic tests, examined pathogenecity of the viruses and examined vector susceptibility of the Japanese mosquitoes. The results are summarized as follows. 1.Development of diagnostic tests. 1)As the genetic diagnostic tests of West Nile virus, RT-PCR RFLP method, a real time PCR method and RT-LAMP method were developed. 2)For tick-borne encephalitis, IgG-and IgM-ELISA using subviral particles were developed as serological diagnostic tests for human. 2.Studies on pathogenecity of flavivirus 1)Neuroinvasive virulence of West Nile virus New York strain was found to be associated with glysosylation of envelope protein. 2)Neuroinvasive virulence of tick-borne encephalitis virus was reduced due to one amino acid change of envelope protein which led to the reduced vircemia. 3.Japanese encephalitis 1)Japanese encephalitis virus from South-East Asian countries often invaded into Japan. 2)RNAi was found to be effective as antiviral agent to Japanese encephalitis viris. 4.Mosquito studies 1)Japanese indigenous mosquitoes of 4 species were found to be susceptible to West Nile virus.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2001 -2003 
    Author : MORIMATSU Kumiko, ONO Eriko, MORIMATSU Masami, KARIWA Hiroaki, ARIKAWA Jiro
     
    1. It was clarified that recombinant Hantavirus envelope glycoproteins G1 and G2 (GPs) had the cell-fusion activity by using CAG promotor-expression system. Fusion-responsible epitope on GPs was found to locate in the neutralization (FRNT)-relating epitope. Therefore, the recombinant GPs was considered to possess neutralization-and fusion-relating epitopes. In addition, hantavirus nucleocapsid (N) protein was also expressed in mammalian cells by using same vector. As the result the N protein may suppress that expression and transportation of the envelope protein. It was also shown that the virus like particle was not formed by GPs and N protein alone. 2. By using recombinant GPs, pseudotype vesicular stomatitis virus (VSV) enveloped with hantavirus GPs altered to VSV G protein was produced (VSVΔG*HTN). Similar pseudotype VSV was produced with recombinant GPs of Seoul virus (VSVΔG*SEO). These pseudotypes were applied to rapid neutralization assay as safety alternatives of authentic viruses. These pseudotype virus particles were also applied to vaccination as alternatives to authentic virion. Mice were immunized with soluble recombinant GPs or pseudotype virion. In mice immunized with soluble recombinant GPs, FRNT antibody was not detected. Contrary, in mice immunized with VSVΔG*HTN virion, FRNT antibody was detected. Challenge administration of hantavirus was carried out by s.c. inoculation of 4 FFU of hantavirus. These mice did not show the elevation of anti-N antibody and hantavirus specific CD8 T cell response, indicating that the FRNT antibody could protect mice from hantavirus infection. On the other hand, all control mice immunized with VSVΔG*G or PBS could not escape from hantavirus infection. These results indicated that packaged recombinant GPs on VSV particle were possible to induce protective FRNT antibody. This study shows that novel approach for the development of vaccination of viruses that have difficulties in preparation of authentic virus particles.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2001 -2003 
    Author : KARIWA Hiroaki, ARIKAWA Jiro, MIZUTANI Tetsuya, TAKASIMA Ikuo, IWASAKI Takuya
     
    To know the epidemiology of viral zoonotic diseases such as hemorrhagic fever with renal syndrome (HFRS) and tick-borne encephalitis (TBE) in Far East Russia, we Conducted an epizootiological survey in Khabarovsk. Anti-hantavirus antibodies were detected in Apodemus.agrarius (5/47), and Clethrionomys rufocanus (7/40) among 102 small animals captured. Partial M segments were amplified from seropositive A.agrarius. The virus nucleotide sequence in G2 region (2695-2926nt) from A agrarius had 97.0 -99.6% identities with those of FE genotypes which were identified from blood samples of HFRS patients. On the contrary, the sequence had 80.7 to 82.5% identities with those of AMR. These results suggest that hantavirus FE genotype cases severe HFRS and is carried by A agrarius. We established the ELISA to detect anti-TBE virus antibodies by using the recombinant viral E protein expressed in E.coli expression system. The ELISA could detected anti-TBE virus antibodies in C.rufocanus captured in Khabarovsk, which were also positive by authentic neutralization test. This indicate that the ELISA can be a useful method to identify the endemic areas of TBE.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2001 -2003 
    Author : KARIWA Hiroaki, ARIKAWA Jiro, MIZUTANI Tetsuya, TAKASHIMA Ikuo, FUKUSHIMA Hiroshi, TUCHIYA Kimiyuki, ANDO Shuji
     
    To know the epidemiology of viral zoonotic diseases such as hemorrhagic fever with renal syndrome (HFRS) and tick-borne encephalitis (TBE) in Japan, we conducted an epizootiological survey in various points of Japan. Anti-hantavirus antibodies were detected in Apodemus. speciosus (5/482), and Clethnonomys rufocanus (7/197), Rattus norvegicus (4/364), and Rattus rattus (3/45) by Indirect fluorescent antibody assay (IFA). The positive sera from A.speciosus neutralized Hantaan virus at 1:20 but did not neutralize Seoul virus. This indicate that hantavirus carried by A.speciosus is closer to Hantaan virus than Seoul virus. The partial S gene was amplified from seropositive R.rattus and sequenced. The virus sequence had 96% identitiy with SR-11 which is Seoul virus prototype strain. These results suggest that main reservoir animals of hantavirus in Japan are A.speciosus, C. rufocanus, R.norvegicus, and R rattus. The rodent sera were applied to the newly established ELISA by using recombinant E protein of TBE virus to detected anti-TBE virus antibodies. The ELISA could detect anti-TBE antibodies in sera positive by neutralization test. However, no antibodies were detected in rodent sera from Toyama prefecture, in which TBE infections has not confirmed. These results suggest that the ELISA can be a useful method to identify the endemic areas of TBE in Japan.
  • SARSコロナウイルスのウイルス粒子形成機構に関する研究
    Date (from‐to) : 2003
  • Study on the mechanism of virion formation of SARS-coronavirus
    Date (from‐to) : 2003
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2000 -2002 
    Author : TAKASHIMA Ikuo, TAKAHASHI Kenichi, MIZUTANI Tetsuya, KARIWA Hiroaki, KURATA Takeshi, NEJIME Tetsuya
     
    We conducted epidemiological study to specify the endemic area of tick-borne encephalitis (TBE), evaluated the pathogenicity of TBE virus Hokkaido strain and tested the efficacy of European TBE vaccine to Hokkaido TBE virus strain. We also performed phylogenetic study of TBE virus Hokkaido strainsto estimate the origin. The results showed that TBE virus distribute in southern part of Hokkaido from the positive antibody results in dog and horse sera. Reservoir animals of TBE virus in Hokkaido were found to be Clethrionomys rufocanus and Apodemus speciosus from virus isolation results. TBE virus Hokkaido strains possessed common pathogenicity shared among TBE virus strains. TBE virus Hokkaido strain diverged from ancestor virus in Far East several hundred years ago. Another subtype of TBE virus, Siberian subtype was found to distribute in Siberian area of Russia. European type TBE virus vaccine was found to be efficacious to TBE virus Hokkaido, Far Eastern and Siberian strains. Monochlonal antibodies against TBE virus Hokkaido strain were produced and found to be useful for diagnosis.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1999 -2001 
    Author : TAKASHIMA Ikuo, TAKAHASHI Kenichi, IWASAKI Takuya, KARIWA Hiroaki, MIZUTANI Tetsuya, MARUYAMA Tsutomu
     
    We conducted epidemiclogical study to specify the endemic area of tick-borne encephalitis (TBE), evaluated the pathogenicity of TBE virus Hokkaido strain and tested the efficacy of European TBE vaccine to Hokkaido TBE virus strain. We also performed phylogenetic study of TBE virus Hokkai strains to estimate the origin. The results showed that TBE virus distribute in southern part of Hokkaido from the positive antibody results in dog and horse sera. Reservoir animals of TBE virus in Hokkaido were found to Clethrionomys rufocanus and Apodemus speciosus from virus isolation result. TBE virus Hokkaido strains possessed common pathogenicity shared among TBE virus strains. TBE virus Hokkaido strain diverged from ancestor virus in Far East several hundred years ago. Another subtype of TBE virus Siberian subtype was found to distribute in Siberian area of Russia. European type TBE virus vaccine was found to be efficacious to TBE virus Hokkaido, Far Eastern and Siberian strains. Monoclonal antibodies against TBE virus Hokkaido strain were produced and found to be useful for diagnosis.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1999 -2001 
    Author : ARIKAWA Jiro, MORIMATSU Kumiko, KARIWA Hiroaki, SATO Hiroshi, TAKAKURA Akira
     
    1. Nucleocapsid (N) proteins of Hantaan, Seoul and Dobrava viruses were expressed by E. coli and baculovirus systems. The recombinant proteins by both systems produced enough amount of recombinant proteins and retained the anti genicity similar to those of authentic viruses. They are considered to be a ble to apply for ELISA antigen. 2. The truncated N proteins which lacked 50 amino acids at N-terminal reduced the cross reactivity to antibody to heterologous serotypes. Therefore, the truncated antigens were applied as serotyping antigen.The ELISA with the truncated antigen able to serotype of patient and rodent sera from China and Far Eastern part of Russia as determined by ordinary neutralization test. 3. Mouse hepatitis virus N protein gene was expressed by yeast system of which maximum expression was observed at 72 hours after culture. However, the antigenicity was too low to apply for ELISA antigen. 4. cDNA of N protein of lymphocytic choriomeningitis (LCM) virus were cloned from Japanese isolate (strain OQ28) and prototype strain (strain WE). The cDNAs of full length, C-terminal region and central region were independently transfected to COS cells. Although they could express recombinant proteins, amount of antigen expressed was too small to apply to ELISA. 5. Recombinant baculovirus expressing LCM virus N protein was provided from National Institute of Infectious Diseases Japan. Both the recombinant baculovirus infected SF-9 cells and Tm5 cells were found to be applicable for IFA antigen and ELISA antigen, respectively. A total of 9,840 mouse sera from 1,117 animal facility in Japan were tested for LCM virus antibody by IFA and ELISA. From these results, screening with ELISA followed by confirmation by IFA was recommended.
  • 本邦と極東ロシアのげっ歯類におけるハンタウイルスの比較疫学的研究
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 1998/04 -2000/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B).
    Date (from‐to) : 1999 -2000 
    Author : ARIKAWA Jiro, MORIMATSU Kumiko, KARIWA Hiroaki, TAKASHIMA Ikuo, MORIKAWA Shigeru
     
    1. Epidemiologic conditions and status of vaccine development in China were investigated. Information regarding to nucleotide sequence of Chinese isolates and diagnostic procedures for serodiagnosis were exchanged. 2. Technical information for genetic characterization of hantavirus was obtained from Slovak scientist. 3. Technical information for characterization of hantavirus receptor and genetic reassortant virus was obtained from US scientist. 4. Techniques for construction of artificial hantavirus was obtained from scientist of Wisconsin University School of Veterinary Medicine. 5. Information regarding to Nephropathia epidemica virus pathogenicity was obtained from Dr.Antti Vaheri of Helsinki University. 6. Information of epidemiologic and epizootiologic conditions in South East Asia was obtained from scientist in Thai. 7. Infection enhancement by the GalNac specific lectin, DBA and SBA was confirmed. Involvement of cellular factor on the virus cell membrane fusion was elucidated. 8. Pathogenicity to mice was related to growth rated at peripheral cite. The difference was considered to caused by the point mutation at enveloped protein. 9. Viral S and M genome was cloned and expressed in the mammalian cells. Several kinds of mini-genomes were constructed for the examination of role for transcription and translation. For the next step, relationship between the minigenome expression and the proteins expressed by S and M genomes will be required.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A).
    Date (from‐to) : 1998 -2000 
    Author : ARIKAWA Jiro, MORIKAWA Shigeru, KARIWA Hiroaki, MORIMATSU Kumiko
     
    1. Hantavirus infection was enhanced about 10 times by addition of lectins (DBA and SBA) which specifically bind to N-acetylgalactosamine. This enhancement was considered to caused by the cross linking between receptor to virion by the lectins. 2. Two Vero E6 cell subclones, one induce low pH dependent cell fusion after hantavirus infection and the other resistant to cause cell fusion, were established. By using the two cell clones, the possible role for the cellular factor for responsible for induce infected cell fusion was considered. 3. After peripheral infection of hantavirus to mice, virulent virus reached to brain 4 to 5 days earlier than that of avirulent virus. This difference was considered as a mechanism which define the virulence of hantavirus in the mouse model. 4. Virulent hantavirus showed higher growth rate in the brain micro vascular cells and peritoneal macrophage, suggesting that virulence relates to the growth ability in the target organs. 5. Genetic reassortant virus between virulent and avirulent viruses were established. The comparison of the virulence of the reassortant viruses indicated that one amino acid difference at enveloped protein and nucleotide difference in the polymerase gene are related to the virulence. 6. Virulent hantavirus infected SCID mice were passively transferred with spleen cells of immunized BALB/c mice 3 weeks after infection. The recipient SCID mice represented apparent weight loss 4 days after the transfer, indicating the immune mediated pathogenicity. 7. Hantaan virus S and M genome segment which encoding nucleocapsid protein and enveloped glycoprotein, respectively were cloned and expressed in the mammalian cells. 8. Entire L genome segment which encodes polymerase was cloned. The expression of the L clone is under going.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 1998 -1999 
    Author : KARIWA Hiroaki, MIZUTANI Tetsuya, ARIKAWA Jiro, TAKASHIMA Ikuo, YOSHIMATSU Kumiko
     
    Epidemiological study was conducted in Japan and Far East Russia and the followings were revealed. 1. Hantavirus was identified in the urine from infected rats. Since newborn rats intranasally inoculated with the urine containing virus had the virus in their organs and urine, the virus may be maintained by the transmission with virus-contaminated urine by intranasal route in nature. 2. Enzyme linked immunosorbent assay (ELISA) using baculovirus-expressed nucleocapsid proteins of different hantaviruses as antigens was established. This assay made it possible to detect hantaviral antibody and also identify the type of infected hantavirus when sera were reacted with different antigens. 3. To evaluate the virus load in patients of hantavirus pulmonary syndrome (HPS), quantitative PCR system was established. According this PCR, it was revealed that high amount of virus was detectable in blood of acute HPS patients but the virus was disappeared form blood in convalescent phase. 4. Large scale of epidemiological study of hantavirus was conducted in Japan by using severa serological methods. In healthy adults, no one had hantaviral antibody while in hepatic disease patients of unknown etiology, 2 to 3 % of cases had the antibodies. Therefore, it is no doubt that the general public in Japan have hantavirus infections. 5. Epizootiologic study of hantavirus targeting for rodents was carried out in Vladivostok, Far East Russia. Hantaviral antibody was detected in gray-backed vole (Clethrionomys rufocanus), hich is known to be a reservoir of Puumala type hantavirus in Hokkaido, Japan. Since stripped field mice (Apodemus agrarius), which is a reservoir of Hantaan type hantavirus in China and Korea, also had the antibodies, highly virulent strain may be prevalent in Far Eastern Russia. In addition, hantavirus genome was identified in reed vole (Microtis fortis) and sequence analysis revealed that this virus was distinct from other known hantaviruses.
  • フラビウイルスの疫学的研究
    Date (from‐to) : 1999
  • Epidemiological study of flaviviruses
    Date (from‐to) : 1999
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 1996 -1998 
    Author : TAKASHIMA Ikuo, MARUYAMA Tsutomu, MORITA Chiharu, KANEKO Kenichi, ARIKAWA Jiro, KARIWA Hiroaki
     
    1) Tick-borne encephalitis ; Endemic areas of tick-borne encephalitis were distributed in 4 districs of southern Hokkaido. Two strains of tick-borne encephalitis were isolated from 600 individuals of Ixodes ovatus ticks, giving a field infection rate of 0.3% (2/600). Two strains of the virus were isolated from rodents, one from Apodemus speciosus and another from Clethrionomis rufocanus. Oshima Strain isolated previously from dog showed common neuro-invasive virulence. Vaccine in Austria was effective against Hokkaido strain of tick-borne encephalitis virus. 2) Hantavirus infection ; Enzyme-linked immunosorbent assay was developed to diagnose the hantavirus infection for laboratory rats by using antigen generated by vaculovirus expression vector system. 3) Q feve ; By nucleotide sequence anlysis of 16SrRNA of Coxiella burnetii Japanese isolate, they are found to be composed of one genus and one species. 4) Other zoonoses ; Wild rodents were found to be infected with Yersinia, Salmonella and spotted fever group of Rickettia.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 1995 -1997 
    Author : TAKASHIMA Ikuo, KARIWA Hiroaki
     
    Epidemiological investigations of tick-borne encephalitis were performed in the endemic foci where the tick-borne encephalitis patient was found and also in the other areas in Hokkaido. Results wre summarized as follows. 1) In 1995, three strains of tick-borne enchephalitis virus were isolated from the blood of the sentinel dogs which were kept in the area where the patient was found. 2) Two strains of tick-borne encephalitis were isolated from 600 individuals of Ixodes ovatus ticks, giving a field infection rate of 0.3% (2/600). 3) Two strains of tick-borne encephalitis virus were isolated from rodents, one from Apodemus speciosus and another from Clethrionomis rufocanus. 4) Virus strains isolated from dogs, ticks and rodents were identifiend as Russian Spring Summer encephalitis type of tick-borne encephalitis virus. 5) Endemic ares of the virus were distributed in 4 districs of southern Hokkaido. These results indicate that tick-borne encephalitis virus is endemic in Hokkaido and maintained by the vector ticks Ixodes ovatus and rodents.
  • わが国の野性げっ歯類におけるハンタウイルスの感染調査と新型ハンタウイルスの分離
    日本学術振興会：科学研究費補助金
    Date (from‐to) : 1995/04 -1996/03 
    Author : 苅和 宏明
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 1994 -1996 
    Author : ARIKAWA Jiro, TAKAKURA Akira, SUGIYAMA Kazuyoshi, YOSHIMATSU Kumiko, KARIWA Hiroaki
     
    1. Recombinant baculovirus expressing hantavirus nucleocapsid protein (Bac.HTN-NP) was applied for the antigen of ELISA.Specificity of the ELISA was the same to that of the IFA which uses infected Vero E6 cells as antigen. However, the ELISA had a sensitivity problem because of the relatively high background coloring. 2. cDNA which encoded hantavirus nucleocapsid protein was expressed by using E.coli system and established capture ELISA system. This ELISA was shown to have same specificity and sensitivity to that of the ordinally IFA,and therefore, considered as a useful screening method. 3. Bac.HTN-NP was successfully applied for the antigen for Western blotting (WB). The WB method readily distinguished specific reaction from nonspecific reaction from the WB pattern. Therefore, the WB was considered as an effective method for the serologic confirmation of hantavirus infection.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 1994 -1996 
    Author : ARIKAWA Jiro, TANIGUCHI Koki, KARIWA Hiroaki, KIDA Hiroshi, AZUMA Ichiro
     
    1. Animal models for studying respiratory infection, enteric infection and systemic infections were established by using mice and Sendai virus, rotavirus and hantavirus, respectively. 2. MDP-Lys (L18) was selected as a immunoadjuvant and examined its effect on the enhancement of protection from infection after its administration by oral, intranasal, intrarectal and subcutaneous routes. 3. Fatal Sendai virus infection was significantly reduced by administration of MDP-Lys (L18) through intranasal, ora and even intra rectal route. 4. Rota virus diarrhea was significantly reduced by administration of MDP-Lys (L18) through subcutaneous, oral and intrarectal route. 5. Fatal hantavirus infection was significantly reduced only by the administration of MDP-Lys (L18) through subcutaneous route. These results suggested the effect of immunoadjuvant on the augmentation of host immunity by common mucosa immune system. Further studies concerning to the quantitative estimation of the augmentation of host immunity. In addition, enhancement of specific immunity against vaccine antigen by the combination of the immunoadjuvant and mucosal administration should be studied.
  • ハンタウイルスの生態学的研究
    Date (from‐to) : 1990
  • Ecological study of hantaviruses
    Date (from‐to) : 1990

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