Whole-life tracing and cell-cell regulation in B cells

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22538
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 49:Pathology, infection/immunology, and related fields
• Research Institution: Hiroshima University
• Principal Investigator: YASUDA TOMOHARU 広島大学, 医系科学研究科(医), 教授 (40334429)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: B細胞 / 免疫老化 / 免疫寿命 / 細胞老化 / 免疫応答

Outline of Final Research Achievements

Labeled EYFP-expressing B cells could be rejected by the immune system, however T cells were not activated and labeled B cells had not rejected by the immune system more than 180 days after labeling. Thus confirmed that the labeling of differentiated B cells and the absolute measurement of lifespan are possible using this system. As a result of tracking the labeled B cells for one year, we found that the B cells were replaced in a short period during young age, but the turnover decreased as aging. In addition, we succeeded to find that naive B cells that have not been activated by the antigen stay circulation in vivo for a much longer period of time than previously thought.

Free Research Field

免疫

Academic Significance and Societal Importance of the Research Achievements

外来抗原に特異的な免疫記憶（抗体産生細胞、記憶B細胞、記憶T細胞から構成される）を形成する個々の細胞が維持される期間を明らかにすることは、免疫記憶の成り立ちを理解する根幹に関わりその重要性は明白である。記憶細胞の生存期間が定量化できるようになれば、生存期間ごとに細胞を解析できるようになるため特定細胞の長期生存を可能にする分子メカニズムに迫ることもできる。このような解析を進めていくことで免疫記憶の成り立ちや抗体選択のメカニズムのさらなる理解に貢献し、効果的なワクチン開発、アレルギーや自己免疫などの疾患治療に役立つことが期待できる。