RORγt-driven T(H)17 Cell Differentiation Requires Epigenetic Control by the Swi/Snf Chromatin Remodeling Complex

Epigenetic regulation, including chromatin accessibility and posttranslational modifications of histones, is of importance for T cell lineage decision. T(H)17 cells play a critical role in protective mucosal immunity and pathogenic multiple autoimmune diseases. The differentiation of T(H)17 cells is dictated by a master transcription factor, RORγt. However, the epigenetic mechanism that controls T(H)17 cell differentiation remains poorly understood. Here we show that the Swi/Snf complex is required for T(H)17-mediated cytokine production both in vitro and in vivo. We demonstrate that RORγt recruits and forms a complex with the Swi/Snf complex to cooperate for the RORγt-mediated epigenetic modifications of target genes, including both permissive and repressive ones for T(H)17 cell differentiation. Our findings thus highlight the Swi/Snf complex as an essential epigenetic regulator of T(H)17 cell differentiation and provide a basis for the understanding of how a master transcription factor RORγt collaborates with the Swi/Snf complex to govern epigenetic regulation.