Whole transcriptome sequencing of Treg with and without Rcor1 deletion

Foxp3+ T-regulatory (Treg) cells have well established roles in maintaining immune homeostasis and tolerance, but the contributions of several large multiprotein complexes that regulate gene expression remain unexplored in Tregs. We analyzed the role in Tregs of the evolutionarily conserved CoREST complex that consists of a scaffolding protein, Rcor1 or Rcor2, plus Hdac1, Hdac2 and Lsd1 enzymes. We found Rcor1, Rcor2 and Lsd1 were physically associated with Foxp3, and that mice with conditional deletion of Rcor1 in Foxp3+ Treg cells had decreased proportions of Tregs in their peripheral lymphoid tissues, and increased Treg expression of IL-2 and IFN-g compared to WT cells. In vivo, compared with WT mice, mice with conditional deletion of Rcor1 in their Tregs had reduced suppression of homeostatic proliferation, inability to maintain long-term allograft survival despite costimulation blockade, and enhanced antitumor immunity in syngeneic models. Comparable findings were seen in WT mice treated with a CoREST inhibitor. Our data point to the potential for therapeutic modulation of Treg functions by pharmacologic targeting of enzymatic components of the CoREST complex, and contribute to an understanding of the biochemical and molecular mechanisms by which Foxp3 represses large gene sets and maintains the unique properties of this key immune cell type. Overall design: Foxp3+ regulatory T cells from mice with or without a Foxp3-conditional Rcor1 deletion (Rcor1fl/flFoxp3YFPcre and Foxp3YFPcre mice) had RNA isolated. The RNA samples, with three independent biological replicates per group, were sent to NovoGene for mRNA sequencing using the Illuminia PE150 platform.