TNF and IFN-γ impact antigen presentation after BMT. (A) A total of 10⁷ B6.WT TCD BM (non-GVHD) + 0.2 × 10⁶ CD3⁺ B6.WT CD3⁺ T cells (GVHD), or 0.2 × 10⁶ CD4 or CD8 T cells, or 0.2 × 10⁶ IFN-γ^−/− CD3⁺ T cells were transferred into lethally irradiated (900 cGy, day 0) BALB/c recipients on day 0. Anti-NK1.1 antibody was used to deplete donor NK cells and was administered to recipients at day 1, 3, 5, 7, and 9 after transplantation (1 mg/dose). B cell-deficient (μMT) donors were used to assess the role of donor B cells. B6.DEREG grafts were transferred in parallel to B6.WT grafts, and all recipient mice were treated with DT after transplantation to deplete T_reg cells. Grafts were B6.pfp^−/−, B6.Grzb^−/−, or B6.WT. TEa T cells were transferred at day 7 after transplantation, and proliferation was assessed as described. n = 15 in TCD, n = 16 in CD3⁺ control arm; n = 5 in CD4⁺/8⁺ and anti-NK1.1 treated groups; n = 4, μMT arm; n = 7, IFN-γ^−/− T cell arm. For T_reg depletion experiments, n = 4/group, B6.WT donors; n = 7 or 8/group, B6.DEREG donors; n = 4/group for pfp^−/− and grzb^−/− experiments. *Statistical significance between the relevant control non-GVHD arm and the GVHD test group: *P = .05 to .01. **P = .01 to .001. ***P < .001. (B) BM grafts deficient in cytokine receptors or incapable of cytokine production were used as labeled, and Ag presentation measured at day 10, as previously described. T cells were of WT.B6 origin. Blocking antibodies and 1-MT were used as described in “Cell depletion and cytokine neutralization,” and TEa T cells were transferred as described previously. Data are representative of 16 separate experiments. n = 3 (TGF-β TCD) − 36 (WT TCD and BM + T)/group. #Statistical significance between the test GVHD and WT GVHD arms: ##P = .01 to .001; ###P < .001. †Statistical significance between the test non-GVHD and WT non-GVHD arms: †††P < .001. (C) Serum cytokines were analyzed at day 3, 5, 7, and 10 after transplantation of either B6.WT TCD BM grafts (non-GVHD) or TCD BM + CD3⁺ T (GVHD).