IFNG and colitis: To investigate the role of mPGES-1 in the development of Th17/Th1 immune responses involved in colitis, we next analyzed the proportions of Th17 and Th1 cells that produced IL-17A and IFNγ in mesenteric lymph nodes (MLNs) of mPGES-1−/− and WT mice following colitis induction.