TFF3 and colitis: Indeed, CDX2 is a positive regulator of the Muc2 and Trefoil Factor 3 (TFF3) genes [56,118] involved in the production and stabilization of the mucus layer, respectively, and whose deficiency induces hypersensitivity to chemically-induced colitis (such as that induced by dextran sulfate sodium (DSS)) [15,56].