Role of D6^−/− Gr1⁺ cells in GVHD protection. (A) Survival curves and (B) clinical scores of WT (□) or D6^−/− (■) BALB/c mice transplanted with BM and WS taken from WT B6. Serum level of mIFN-γ (C) and mCCL2/JE (D) measured at day 3 and day 6 after transplantation (2 independent experiments, n = 6 mice/group). Data are mean ± SD. *P < .05, D6^−/− and WT versus control mice. #P < .05, D6^−/− versus WT mice. (E) Fold increase of absolute number ± SD of CD11b⁺/Ly6C^high and CD11b⁺ Ly6G⁺ cells of D6^−/− (black bar) mice versus WT (white bar) BALB/c recipients (2 independent experiments, n = 6 mice/group). *P < .05, D6^−/− versus WT mice. **P < .005, D6^−/− versus WT mice. (F) Survival curves of WT (open symbols) or D6^−/− (closed symbols) BALB/c mice transplanted with BM and WS taken from WT B6, treated with isotype (squares) or anti-Gr1 (circles). (G) WT BALB/c transplanted with BM and CD3⁺ cells taken from WT B6, treated with CD11b⁺/Gr1⁺ cells from WT (□) or D6^−/− (■) B6 mice. In all experiments, control mice (▾) were transplanted with syngeneic BM and WS. Data are representative of 2 independent experiments (n = 8 mice/group).