We have previously shown that PGE2 promotes intestinal ILC3 activation and IL-22 production.7 To examine whether PGE2 similarly regulates lung ILC3s and whether this leads to suppression of acute lung inflammation, we treated naïve mice with indomethacin, a cyclooxygenase inhibitor that inhibits endogenous PGE2 synthesis. The gene discussed is IL22; the disease is inflammatory response.