ADSL and colitis: Commensal bacteria or their metabolites have been shown to activate AhR, which reduces microbial translocation and fibrosis in the gut, thus contributing to the restoration of gut homeostasis.[7, 18] Also, it has been demonstrated that gut microbiota stimulate the expression of antimicrobial peptides such as RegIIIc and certain defensins by the CECs, and that epithelial cell‐produced AMPs are essential for maintaining intestinal homeostasis by controlling microbiota.[10, 27] We therefore studied the impact of AhR‐mediated induction of mBD‐1 on microbial dysbiosis in colitis mice.