Project/Area Number |
22KJ1390
|
Project/Area Number (Other) |
20J22961 (2020-2022)
|
Research Category |
Grant-in-Aid for JSPS Fellows
|
Allocation Type | Multi-year Fund (2023) Single-year Grants (2020-2022) |
Section | 国内 |
Review Section |
Basic Section 40040:Aquatic life science-related
|
Research Institution | Tokyo University of Marine Science and Technology |
Principal Investigator |
Lau Lik Ming 東京海洋大学, 大学院海洋科学技術研究科, 特別研究員(DC1)
|
Project Period (FY) |
2023-03-08 – 2024-03-31
|
Project Status |
Completed (Fiscal Year 2023)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 2023: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 2022: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2021: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2020: ¥600,000 (Direct Cost: ¥600,000)
|
Keywords | CD4-1 / CD4-2 / Ginbuna crucian carp / Cell-mediated immunity / CD8α |
Outline of Research at the Start |
The largest obstacle in vaccine development for aquaculture is that the mechanism of cell-mediated immunity (CMI) has not been fully understood in fish. Fish has two types of CD4: CD4-1 resembles the mammalian CD4 while CD4-2 is a unique CD4 homolog. Fish CD4-1 cells play an important role in humoral immunity, but not in the CMI. Hence, CD4-2 cells may include the CMI of fish. Hence, a monoclonal antibody against fish CD4-2 was developed to study the unique CD4-2 cells from different perspectives:(1) morphological characteristics; (2) tissue distribution; and (3) roles in CMI of fish.
|
Outline of Annual Research Achievements |
In fiscal year (FY) 2023, in vivo transplantation of stimulated leukocytes from donor fish into recipient fish, and in vitro cytotoxicity assay of effector cells were studied using ginbuna as a model fish species. Through in vivo transplantation studies, I found that naive recipients who received stimulated leukocytes from peripheral blood and spleen of vaccinated donors tend to have a higher survival rate (90%) than those who received stimulated leukocytes from trunk-kidney and head-kidney (40%). These findings indicated that the majority of memory cells moved to a major secondary lymphoid organ such as the spleen and circulated in the systemic blood of ginbuna. Through in vitro cytotoxicity studies, regardless of stimulated or non-stimulated leukocytes, I realized that the cytotoxic activities of naive recipients who received donor cells with CD4-1 positive cells were higher than those of fish who received donor cells with CD4-2 positive cells. These results suggested that the adoptive transfer of stimulated leukocytes with CD4-1 positive cells rather than CD4-2 positive cells provided naive recipients efficient cytotoxic activity against virus-infected cells. However, naive recipients that received unsorted leukocytes from vaccinated donors following a secondary virus infection showed higher cytotoxic activities than those aforementioned treatment groups. These results suggested that secondary cell-mediated immunity is probably enhanced by CD4-1 and CD4-2 positive cells in ginbuna against a virus infection.
|