 Constitutive overexpression and mir-shRNA-mediated knockdown studies showed that expression of Jak3 was necessary for IL-2-induced proliferation of IEC.Additionally, IL-2-induced downregulation of jak3-mRNA was responsible for higher IL-2-induced apoptosis in IEC.Thus IL-2-induced mucosal homeostasis through posttranslational and transcriptional regulation of Jak3.