IL22 and graft versus host disease: To determine whether IL-22 from RORγt+ Th/Tc17 cells is required for induction of SR-Gut-aGVHD, we compared 4-DEX-treated GVHD recipients given 1.5 × 106 splenic T cells from WT or RORγt−/− C57BL/6 donors with TCD-BM from WT C57BL/6 donors.