Figure 7.

Illustrative summary of IL22 signal modulation by AhR. IL22 is produced by gut immune cells, such as group 3 innate lymphoid cells (ILC3s), binds to the IL22 receptor in colonic stem/progenitor cells, and induces the phosphorylation of STAT3. pSTAT3 induces the expression of antimicrobial peptides Reg3β/γ. In addition, pSTAT3 enhances γH2AX levels to initiate DNA damage response. Increased expression of SOCS3 by AhR KO inhibits phosphorylation of STAT3 as a negative regulator, thereby attenuating IL22-pSTAT3-mediated effects. AhR, aryl hydrocarbon receptor; KO, knockout; SOCS3, suppressor of cytokine signaling 3; WT, wild type.