Using a clinically relevant model of H-2b MHC-matched, multiple minor antigen–mismatched BMT (B6→129) involving transfer of polyclonal donor CD4+ and CD45.1+ CD8+ T cells, we flow sorted to high purity CD45.1+ CD8+ TE from individual SLOs (blood, spleen, mesenteric/peripheral LNs) and GVHD target organs (skin dermis and epidermis, small intestinal lamina propria [LP] and intraepithelial lymphocyte [IEL] compartments, liver) on day 6 following transplant. Here, CD8A is linked to graft versus host disease.