JAK2 and enterocolitis: It was reported that STAT3 activation in myeloid cells increased anti-inflammatory actions of IL-10, whereas deletion of STAT3 resulted in severe enterocolitis.38 The inhibitory effects of IL-6 on DCs differentiation could be partially prevented by inhibition of STAT3 by the JAK2 inhibitor AG490.39 In STAT3-deficient mice,40 STAT3-dependent regenerating genes Reg3β and Reg3g are also deleted, while colonic expression of SOCS3, a direct downstream gene of STAT3, is significantly increased.