IFNG and autoimmune disease: However, when hMSCs were treated with IFN-γ and TNF-α, prominent cytokines in type 1 helper T cell-mediated autoimmune diseases, such as inflammatory bowel disease, multiple sclerosis and type I diabetes, early-passage hMSCs produced a much higher level of PGE2 in response to cytokine treatment compared to late-passage hMSCs.