Roles of OX40 and IL-7 in homeostasis of memory T cells

2014 Fiscal Year Final Research Report

• Project/Area Number: 24390118
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Immunology
• Research Institution: Tohoku University
• Principal Investigator: ISHII NAOTO 東北大学, 医学(系)研究科(研究院), 教授 (60291267)
• Co-Investigator(Kenkyū-buntansha): SO Takanori 東北大学, 大学院医学系研究科, 准教授 (60294964)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 免疫学 / T細胞 / 恒常性維持

Outline of Final Research Achievements

T-cell homeostasis preserves the numbers, the diversity and functional competence of different T cell subsets that are required for adaptive immunity. It is not clear how memory CD4+ T cell subsets are maintained in the periphery and what factors are responsible for the maintenance. To examine the homeostatic mechanisms, CFSE-labeled CD4+ effector memory T (TEM) cells were transferred into syngeneic C57BL/6 mice, and the systemic cell proliferative responses were assessed by CFSE dye dilution. We found that the fast homeostatic proliferation of TEM cells was strictly regulated by both antigen and OX40 costimulatory signals and that the slow proliferation was dependent on IL-7. The OX40-dependent fast proliferation preferentially expanded IL-17-producing helper T cells (Th17 cells). Together, both OX40 and IL-7 signals are required during homeostasis of TEM cells, and the synergistic signals may be critical for the expansion of Th17 cells.

Free Research Field

免疫学