IL17A and colitis: Intriguingly, the signature cytokine of Th17 cells, IL-17, has been implicated in the suppression of Th1-mediated colitis [78] and even the regulation of Th17 responses themselves [5, 79, 80], Additionally, IL-17 is reported to contribute to the induction of Foxp3+ regulatory T cells (Tregs) in the context of autoimmune uveitis [16].