Antigen degradation and presentation by gill-epithelial antigen sampling cells

2022 Fiscal Year Final Research Report

• Project/Area Number: 17KK0151
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Aquatic bioproduction science
• Research Institution: Tokyo University of Marine Science and Technology
• Principal Investigator: Kato Goshi 東京海洋大学, 学術研究院, 准教授 (50624219)
• Project Period (FY): 2018 – 2022
• Keywords: 魚類免疫学

Outline of Final Research Achievements

Bacterial antigen administrated by immersion vaccination were taken up by gill-epithelial antigen sampling (GAS) cells in rainbow trout. We aimed to elucidate the mechanisms of GAS cells to initialize mucosal immune respoonses after the immersion vaccination. GAS cells were positive for acid phosphatase and lysosome staining, and they can degrade bacterial antigen within 3 h after the immesion. gene expression of CD80 that is essential for antigen presentation was up-regulated at 3 h post immersion. Further, GATA3 gene expression level was up-regulated after the co-culture of GAS cells hoboring the bacterial antigen and lymphocytes of rainbow trout. These data suggest that GAS cells can degrade bacterial antigen within 3 h after uptake and directly present it to T cells for initialization of mucosal immune response in the gill epithelium.

Free Research Field

魚類免疫学

Academic Significance and Societal Importance of the Research Achievements

浸漬ワクチンは稚魚や小型の魚類でも投与することができ、一度に大量に処理できるため、養殖現場からの開発ニーズは非常に高い。しかし、浸漬ワクチンとして有効なものは日本国内で1種類、世界的に見ても3種類の病原体に対するものしかなく、浸漬ワクチン技術の適用範囲の拡大が喫緊の課題である。穂pン研究では浸漬ワクチンの根幹ともなるGAS細胞に焦点を当てて研究を行い、GAS細胞が取り込んだ最近抗原を分解し、抗原提示を行うことで鰓粘膜免疫応答の起点となることを示した。今後、さらに浸漬ワクチンによる免疫応答の誘導機序を明らかにすることで、魚類の新たな浸漬ワクチン技術の開発に貢献できる。