BioProject

IL-27 is a potent antagonist of TH1-mediated inflammation, but the basis for this effect is not fully understood. More...

IL-27 is a potent antagonist of TH1-mediated inflammation, but the basis for this effect is not fully understood. Recent studies identified a population of T-bet+ CXCR3+ Treg that limit TH1-mediated immune pathology. The studies presented here demonstrate that IL-27-mediated STAT1 activation promotes Treg expression of T-bet and CXCR3. Infection with Toxoplasma gondii induced a similar Treg population that limits T cell responses and this population at mucosal sites is IL-27-dependent. Furthermore, transfer of Treg ameliorated the infection-induced CD4+ T cell-mediated pathology observed in IL-27p28-/- mice. Although IFN-γ promoted a similar population of cells in the periphery, it did not compensate for the absence of IL-27 at mucosal sites and microarray analysis revealed that Treg exposed to either cytokine have distinct transcriptional profiles. These findings suggest that IFN-γ and IL-27 have different roles in Treg biology but define IL-27 as a key cytokine that promotes the development of Treg specialized to control TH1 immunity. Overall design: Three conditions were analyzed across two timepoints. Inducible regulatory T cells (iTreg) were generated in vitro in the presence of IL-27, IFNg or under 'Neutral' conditions as a control. Samples were collected at 10 hours and 2 days during the culture period. Three biological replicates were used for each condition. Less...