| 研究実績の概要 |
With the aid of monoclonal antibodies (mAbs) against CD4-1, CD4-2, and CD8α of ginbuna crucian carp (ginbuna), the roles of CD4-2 positive cells in the adaptive immunity of fish were investigated. In fiscal year (FY) 2022, the kinetics of CD4-1, CD4-2, and CD8α positive lymphocytes in ginbuna were studied through three kinds of in vivo experiments: (A) during cyprinid herpesvirus-2 (CyHV-2) infection; (B) under high-temperature water (HT) treatment after CyHV-2 infection; and (C) immunized with a live-attenuated vaccine against CyHV-2 infection. For experiment (A), I found that the number of CD4-1, CD4-2, and CD8α positive lymphocytes increased after CyHV-2 infection, indicating that CD4-2 positive lymphocytes play important roles against herpesvirus infection instead of Mycobacterial infection (reported in FY 2021) in fish. For experiment (B), I realized that the number of CD4-1, CD4-2, and CD8α positive lymphocytes increased rapidly after the secondary CyHV-2 challenge, indicating that the secondary immune responses require the help of both CD4-1 and CD4-2 positive lymphocytes in HT-treated fish. For experiment (C), after subsequent virulent virus challenge, I noticed that the number of CD4-2 positive lymphocytes significantly increased in ginbuna immunized with the live-attenuated vaccine whereas no significant difference was observed in CD4-1 positive lymphocytes. These results suggest that CD4-2 positive lymphocytes can have a different role from CD4-1 positive lymphocytes in fish.
|
| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
Following the original research plan in FY 2022, the roles of CD4-1 and CD4-2 positive lymphocytes were comparatively investigated in ginbuna through in vivo experiments. Through these experiments, CD4-2 positive lymphocytes can have a different role from CD4-1 positive lymphocytes in fish. The CD4-1 positive lymphocytes probably work in the primary immune responses against intracellular pathogens and the CD4-2 positive lymphocytes may have immunological memory function in the secondary immune responses of fish. Some of these research results have already been presented at three domestic conferences in FY 2022, and are also scheduled for an upcoming international conference in FY 2023. The research results obtained in FY 2020 and FY 2021 have been submitted to an international journal for publication.
|
| 今後の研究の推進方策 |
Following the original plan in FY 2023, the helper function of CD4-2 positive cells in the cell-mediated immunity of fish will be studied through in vivo adoptive transplantation of stimulated leukocytes from donor fish into recipient fish, and also in vitro cytotoxicity assay, using ginbuna as the model fish species.
|
