TCR-transduced T cells do not induce graft versus host pathology in partially MHC-mismatched recipients. Colon and liver sections were obtained either 6 weeks after viral infection (A-B) or at the onset of clinical GvHD (C). L indicates lumen; LP, lamina propria; MM, muscularis mucosae; SM, submucosa; ME, muscularis externa; BD, bile duct; PV, portal vein. Lymphocytic infiltrates are present throughout the intestinal wall and in the periportal area of Balb.B recipients (C), whereas intestine and periportal area of partially MHC-mismatched recipients are unaffected (A-B). Original magnification, ×16 (A-B, left panels); ×32 (A-B, right panels); ×125 (C, left panel); and ×20 (C, right panel).