GFAP and colorectal carcinoma: To determine whether lymphocytes as a whole were required for the protective effect of enteric glia depletion, we bred Rag2-/- γc-/- mice to Gfap-tk mice to obtain Gfap-tk mice lacking all lymphocyte populations, then induced CRC in the mice with AOM/DSS and depleted the GFAP+ enteric glia with ganciclovir.