CD4 and Endarteritis: In the present study, we found significant infiltration of donor leukocytes in the kidney, and that infiltration of CD3+ T-cells, CD8+ T-cells, CD4+ T-cells, and macrophages mediated renal inflammation with peritubular capillaritis, tubulitis, acute glomerulitis, and endarteritis in allogeneic BMT recipients with systemic acute GVHD.