A previous study showed that IFNγ+IL-17+coproducing CD4+ T cells as a pathogenic Th17 cells are specifically enriched in the inflamed mucosal tissue of IBD patients but not healthy individuals [70].These enhanced colonic Th17 and Th1 immune responses observed in mPGES-1−/− mice seems to be associated with the abnormalities consistent with the colitis. This evidence concerns the gene IL17A and colitis.