Muscle-residing regulatory T cells (Tregs) control local tissue integrity and function. However, the molecular interface connecting Treg-based regulation with muscle function and regeneration remains largely unexplored. Here, we show that exercise fosters a stable induction of highly functional muscle-residing Tregs with increased expression of amphiregulin (Areg), EGFR, and ST2. Mechanistically, we find that mice lacking IL6Rα on T cells (TKO) harbor significant reductions in muscle Treg functionality and satellite and fibro-adipogenic progenitor cells, which are required for muscle regeneration. Using exercise and sarcopenia models, IL6Rα TKO mice demonstrate deficits in Tregs, their functional maturation, and a more pronounced decline in muscle mass. Muscle injury models indicate that IL6Rα TKO mice have significant disabilities in muscle regeneration. Treg gain of function restores impaired muscle repair in IL6Rα TKO mice. Of note, pharmacological IL6R blockade in WT mice phenocopies deficits in muscle function identified in IL6Rα TKO mice, thereby highlighting the clinical implications of the findings.
FörderungenResearch Group at Helmholtz Zentrum Munchen German Center for Diabetes Research (DZD) EFSD/JDRF/Lilly Program on Type 1 Diabetes Research 2020 Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) Deutsche Forschungsgemeinschaft Alexander von Humboldt Foundation Helmholtz Alliance ICEMED Helmholtz Initiative on Personalized Medicinei Med by the Helmholtz Association Excellence Program for Outstanding Female Scientists from the Helmholtz Association European Research Council(ERC) Helmholtz cross-program topic ''Metabolic Dysfunction'' Initiative and Networking Fund of the Helmholtz Association German Ministry of Education and Research(BMBF) State of Brandenburg (DZD) Core Facility Pathology & Tissue Analytics at Helmholtz Munich