Regulation of pathogenic T helper 17 cell differentiation by steroid receptor coactivator-3

T helper 17 (Th17) cell development is programmed by the orphan nuclear receptor RORgt, but the underlying mechanism is not well understood. Nuclear receptor-mediated transcriptional activation depends on coactivators. Here we show that the steroid receptor coactivator-3 (SRC-3) critically regulates Th17 cell differentiation. Reduced incidence of experimental autoimmune encephalitis (EAE) associated with decreased Th17 cell generation in vivo was observed in mice with SRC-3 deletion specifically in T cells. In vitro, SRC-3 deficiency did not affect TGF-/IL-6-induced Th17 cell generation but severely impaired pathogenic Th17 differentiation induced by IL-1/IL-6/IL-23.

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