GVHD after a B6→B6 × C3H.SW T cell–depleted BMT is both subclinical and sublethal, with hepatic inflammation evident before development of weight loss, and a DLI dose-dependent reduction in lymphocyte reconstitution. (A) In all experiments, T cell–depleted bone marrow was given to irradiated F1 recipients on day 0, followed by a delayed DLI with or without a male DC vaccine on days 14 and 28. (B) Histopathologic analysis of liver GVHD with a dose escalation of DLI. * P < .01, compared with no DLI group, 5 mice/group. (C) Only the liver showed significant lymphocytic infiltration on day 42, shown at both original magnifications ×10 (top panels) and ×40 (bottom panels) from recipients of allogeneic bone marrow alone and allogeneic BMT followed by DLI. (D) Spleens harvested on day 42 were analyzed by flow cytometry for enumeration of lymphocyte subsets. The percentage of the lymphocyte subset was multiplied by the splenocyte count to obtain an absolute number of cells. *P < .01; **P < .001. (E) The DLI dose-response of 0 to 20 × 10⁶ lymph node cells was compared for GVHD-associated weight loss, 5 or 6 mice/group.