AhR agonist 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) activated AhR and induced the production of human Treg cells in vitro, as well as improved 2,4,6-trinitrobenzenesulfonic acid- (TNBS-) induced colitis humanized mice by upregulating the expression of CD39, granzyme B, and IL-10 in vivo [24]. The gene discussed is AHR; the disease is colitis.