AHR and colitis: In mice with dextran sulfate sodium (DSS)-induced colitis, the activation of AHR by 6-Formylindolo (3,2-b) carbazole (FICZ) attenuates the apoptotic rate of CD8αα + TCRαβ+ IELs [52], probably as a result of the increased expression of the IL-15 receptor on the membrane of such cells, which serves as a positive regulator of IEL survival [53,54].