B6-into-BALB/c BMT was performed (850 cGy host irradiation). Cohorts received donor marrow alone ("BMT"); marrow and TS/A tumor cells ("TSA"); marrow, tumor cells, and additional donor T cells ("GVHD"); or marrow, tumor cells, donor T cells, and IL-2 therapy (“GVHD+IL-2”; 50,000 I.U., B.I.D. from day 14 to day 18 post-BMT). Other cohorts received marrow, tumor cells, donor T cells, and donor Th2 cells on day 14 post- BMT either alone ("Th2”) or with IL-2 infusion (“Th2+IL-2”). On day 19 post-BMT, lungs from treatment cohorts were removed to evaluate tumor burden; liver, stomach, small intestine, large intestine, cecum, and skin were harvested to assess GVHD. (a) For GVHD, each organ was scored on a scale of 0 to 4, with cumulative GVHD score shown (maximum value, 24). (b) For tumor burden, a semi-quantitative determination of tumor cell infiltration was scored on a scale of 0 to 4. n = 5 subjects were evaluated per cohort.