Kinetics of B cell subset for antibody production in alloresponse

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K07254
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 48010:Anatomy-related
• Research Institution: Dokkyo Medical University
• Principal Investigator: Kitazawa Yusuke 獨協医科大学, 医学部, 助教 (00467581)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: アロ抗体産生応答 / 辺縁帯B細胞 / 濾胞B細胞 / FITC-Ficoll / FITC-KLH / FITC-Allo T cell / αFITC-AFCs / 形質細胞

Outline of Final Research Achievements

There are two major subgroups of mature B cells in the spleen: follicular B cells (FOB) and marginal zone B cells (MZB), both of which are important cells for inducing humoral immunity. However, their behavior in alloreaction has not been reported. Therefore, we set up an animal model in which MZB or FOB-dependent responses occur, and the dynamic patterns of the AlloB reaction were compared using immunohistochemical staining. The result, alloresponses induced T cell responses (T-dependent) and showed FOB-dominant proliferative responses, such as GC formation associated with FOB responses. Furthermore, antigen-specific AFCs did not show early induction into AFCs as in MZB responses, and showed characteristics similar to those of FOB responses (induction time, kinetic pattern, properties). Therefore, at this stage, it is suggested that alloresponses are FOB-dominant reactions.

Free Research Field

移植免疫学

Academic Significance and Societal Importance of the Research Achievements

研究代表者は、アロT細胞移入後の宿主脾臓outer PALS領域にて独特なB細胞動態を発見した。それは、胚中心（GC）形成前に辺縁帯B細胞（MZB）由来と考えられるAFC応答が起こり、GC形成後に濾胞B細胞（FOB）由来のAFC応答を示したことである。さらに脾摘した宿主に、アロT細胞移入後の宿主血中のドナー抗体価を測定すると、正常（脾臓有り）に比べアロIgM抗体産生が顕著に低下していた。本研究は、アロB応答は、MZBとFOBが混在した独特の動態を示し、脾臓特有のMZBが記憶免疫に関与するとういう新しい学説になるという意義がある。