Control of dynamics and function of T cells by glucocorticoids via IL-7 receptor expression

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K15288
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Immunology
• Research Institution: Kyoto University
• Principal Investigator: Ikuta Koichi 京都大学, ウイルス・再生医科学研究所, 教授 (90193177)
• Co-Investigator(Kenkyū-buntansha): 谷一 靖江 京都大学, 医学研究科, 助教 (50432331)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: ステロイド / T細胞 / IL-7 / 概日リズム / 内分泌系 / 適応免疫 / 糖質コルチコイド

Outline of Final Research Achievements

Glucocorticoids are a group of steroid hormones with strong anti-inflammatory and immunosuppressive effects. However, the physiological function of glucocorticoids in the immune system remains largely unclear. We found that the glucocorticoid receptor induces IL-7 receptor (IL-7R) expression in T cells by binding to the enhancer of the IL-7R locus, and that the induction followed diurnal rhythm of glucocorticoid concentration. The diurnal expression of IL-7R supported T cell survival and triggered T cell redistribution between lymph nodes, spleen, Peyer’s patches and blood by inducing the chemokine receptor, CXCR4. CXCR4 induction triggered T cell migration to spleen and Peyer’s patches. Consequently, T cell accumulation in spleen promoted immune responses against systemic bacterial infection and antigen administration. Our study reveals the immunoenhancing role of glucocorticoids, and provides insights how the immune function is controlled by the diurnal rhythm.

Free Research Field

免疫学