IL1B and colitis: In the 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced mice model, exacerbation of colitis caused by high doses of misoprostol (PGE2 analogs) or PGE1-OH (EP4 agonist) correlated with increased IL-23, a significant accumulation of Th17 cells, together with upregulation of other proinflammatory cytokines including IL-1β and IL-6.