Figure 1. DLI-induced, mHA-mismatched non-lethal GVHD impairs efficacy of TCRTg CD8⁺ T cells.

(A) AlloBMT consisted of CD45.1⁺ T cell depleted (TCD) B6 bone marrow infused into lethally irradiated recipients (B6→B6 × C3H.SW [F1]), followed by an alloreactive CD45.1⁺ B6 DLI at day +14 and adoptive transfer of CD4⁺ CD45.2⁺ or CD8⁺ CD45.2⁺ B6 TCRTg cells +/- male B6 DC vaccine at day +28. F1 recipients were CD45.1⁺CD45.2⁺ double positive. Syngeneic BMT was F1→F1 on day +0 followed by F1 DLI on day +14 and adoptive transfer of CD4⁺ CD45.2⁺ or CD8⁺ CD45.2⁺ B6 TCRTg cells +/- male B6 DC vaccine at day +28. (B) Donor chimerism assessed by flow cytometric analysis for % donor cells in BMT recipient spleens on day +14, 5 mice/group, representative of two independent experiments. (C) Weights were recorded twice weekly per mouse, averaged for the group, and then compared as a % change from the day +0 weight for syngeneic and alloBMT recipients, 5-6 mice/group, representative of three independent experiments. (D) B6 Rag^-/- hosts were injected with CFSE-labeled T cells obtained from CD4⁺ (Marilyn) or CD8⁺ (Matahari) TCRTg splenocytes, and after 7 days, the spleens of the Rag^-/- hosts were analyzed for T cell proliferation. A representative mouse from each group is depicted, n = 3, representative of three independent experiments.