Recombinant mycobacterial DNA-binding protein 1 with post-translational modifications boosts IFN-gamma production from BCG-vaccinated individuals' blood cells in combination with CpG-DNA.
Yuriko Ozeki, Akira Yokoyama, Akihito Nishiyama, Yutaka Yoshida, Yukiko Ohara, Tsukasa Mashima, Chikako Tomiyama, Amina K Shaban, Atsuki Takeishi, Mayuko Osada-Oka, Takehiro Yamaguchi, Yoshitaka Tateishi, Jun-Ichi Maeyama, Mariko Hakamata, Hiroshi Moro, Toshiaki Kikuchi, Daisuke Hayashi, Fumiko Suzuki, Toshiko Yamamoto, Sumiko Iho, Masato Katahira, Saburo Yamamoto, Sohkichi Matsumoto
Scientific reports, 14, 1, 9141, 9141, 21 Apr. 2024, [International Magazine]
English, Scientific journal, Tuberculosis remains a large health threat, despite the availability of the tuberculosis vaccine, BCG. As BCG efficacy gradually decreases from adolescence, BCG-Prime and antigen-booster may be an efficient strategy to confer vaccine efficacy. Mycobacterial DNA-binding protein 1 (MDP1, namely Rv2986c, hupB or HU) is a major Mycobacterium tuberculosis protein that induces vaccine-efficacy by co-administration with CpG DNA. To produce MDP1 for booster-vaccine use, we have created recombinant MDP1 produced in both Escherichia coli (eMDP1) and Mycolicibacterium smegmatis (mMDP1), an avirulent rapid-growing mycobacteria. We tested their immunogenicity by checking interferon (IFN)-gamma production by stimulated peripheral blood cells derived from BCG-vaccinated individuals. Similar to native M. tuberculosis MDP1, we observed that most lysin resides in the C-terminal half of mMDP1 are highly methylated. In contrast, eMDP1 had less post-translational modifications and IFN-gamma stimulation. mMDP1 stimulated the highest amount of IFN-gamma production among the examined native M. tuberculosis proteins including immunodominant MPT32 and Antigen 85 complex. MDP1-mediated IFN-gamma production was more strongly enhanced when combined with a new type of CpG DNA G9.1 than any other tested CpG DNAs. Taken together, these results suggest that the combination of mMDP1 and G9.1 possess high potential use for human booster vaccine against tuberculosis.

Genetic engineering employing MPB70 and its promoter enables efficient secretion and expression of foreign antigen in bacillus Calmette Guérin (BCG) Tokyo.
Atsuki Takeishi, Amina K Shaban, Taichi Kakihana, Hayato Takihara, Shujiro Okuda, Hidekazu Osada, Desak Nyoman Surya Suameitria Dewi, Yuriko Ozeki, Yutaka Yoshida, Akihito Nishiyama, Yoshitaka Tateishi, Yuki Aizu, Yasushi Chuma, Kazuyo Onishi, Daisuke Hayashi, Saburo Yamamoto, Tetsu Mukai, Manabu Ato, Duong Huu Thai, Huynh Thi Thao Nhi, Tsuyoshi Shirai, Satoshi Shibata, Fumiko Obata, Jun Fujii, Seiya Yamayoshi, Maki Kiso, Sohkichi Matsumoto
Microbiology and immunology, 68, 4, 130, 147, Apr. 2024, [International Magazine]
English, Scientific journal, Vaccination is an important factor in public health. The recombinant bacillus Calmette Guérin (rBCG) vaccine, which expresses foreign antigens, is expected to be a superior vaccine against infectious diseases. Here, we report a new recombination platform in which the BCG Tokyo strain is transformed with nucleotide sequences encoding foreign protein fused with the MPB70 immunogenic protein precursor. By RNA-sequencing, mpb70 was found to be the most transcribed among all known genes of BCG Tokyo. Small oligopeptide, namely, polyhistidine tag, was able to be expressed in and secreted from rBCG through a process in which polyhistidine tag fused with intact MPB70 were transcribed by an mpb70 promoter. This methodology was applied to develop an rBCG expressing the receptor binding domain (RBD) of severe acute respiratory syndrome coronavirus 2. Immunoblotting images and mass spectrometry data showed that RBD was also secreted from rBCG. Sera from mice vaccinated with the rBCG showed a tendency of weak neutralizing capacity. The secretion was retained even after a freeze-drying process. The freeze-dried rBCG was administered to and recovered from mice. Recovered rBCG kept secreting RBD. Collectively, our recombination platform offers stable secretion of foreign antigens and can be applied to the development of practical rBCGs.

【ワクチン設計のサイエンス】Bacterial vector BCGベクターワクチン設計のサイエンス
竹石 惇樹, 長田 秀和, 松本 壮吉, 医学のあゆみ, 279, 10, 1041, 1046, Dec. 2021
医歯薬出版(株), Japanese