Survival and GVHD scores of B6D2 mice receiving WT or CCR7^−/− T_reg cells before WT T_n cell dosing. (A-B) B6D2 recipients were lethally irradiated on day −1 and then administered 3 × 10⁶ TCD BM cells from WT B6 donors with or without 1 × 10⁶ column-purified CD4⁺CD25⁺ T_reg cells from WT B6 or CCR7^−/− B6 mice on day 0. A total of 4 × 10⁶ CD25-depleted T_n cells from WT B6 donors were then administered on day +2.²³  n = 4 BM, 7 BM/T_n, 9 BM/T_n/WT T_reg, 9BM/T_n/CCR7^−/− T_reg. (B) *P = .094 for comparison of GVHD scores between WT T_reg and CCR7^−/− T_reg groups on day +70. Error bars indicate SEM.