Is regulatory B cell the cause of immunodeficiency in sepsis?: The relationship with PD-L1 expression

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K18327
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55060:Emergency medicine-related
• Research Institution: Ehime University
• Principal Investigator: Matsumoto Hironori 愛媛大学, 医学系研究科, 助教 (70772531)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 敗血症

Outline of Final Research Achievements

In recent years, the immunosuppressive state, one of the pathologies of sepsis, has been attracting attention, but the immune response in sepsis is not well understood in detail. Through animal experiments, we analyzed the dynamics of immune cells associated with sepsis and found that while B cells drastically decrease in the　acute phase, only IL-10 producing regulatory B cells remain and express PD-L1. In the current study, IL-5 was found to be associated with survival rate, coagulation disorders, and bacterial clearance in the peritoneal cavity during the septic state. IL-5 production by Th2 and ILC-2 cells was confirmed in the peritoneal cavity; however, no correlation was observed between IL-5 and the expression of PD-1 and PD-L1.

Free Research Field

敗血症

Academic Significance and Societal Importance of the Research Achievements

近年、PD-1/PD-L1の相互作用を抑制し、T細胞の活性化抑制を阻止することよる免疫賦活療法が、癌治療で劇的な効果を上げ注目を浴びている。今回、敗血症におけるPD-1抗体の敗血症への応用を目的として、PD-1、PD-L1の発現との関連を中心とした、敗血症に特徴的な免疫応答を明らかとすることである。