Impairing CD62L on donor T cells has minimal impact on GVHD. Survival curves are shown. (A) On day 0, BALB/c recipients received 800 cGy and 10⁷ BM cells from WT B6 donors with or without 3 × 10⁵ CD4⁺CD25⁻ cells from WT B6 or CD62L^−/− (B6) donors. Mice that received WT CD4⁺CD25⁻ cells were injected on days −1 (intravenous), +2 (intraperitoneal) and +5 (intraperitoneal) with 250 μg of Mel-14 or control Rat IgG. *P < .05 for CD4 + Mel-14 versus CD4 + Rat IgG. P = .3334 for WT CD4 + Rat IgG versus CD62L^−/− CD4. (B) BALB/c recipients were splenectomized (Spl⁻) or left intact (Spl intact) 3 weeks before BMT. On day 0, recipients received 800 cGy and 10⁷ BM cells from WT B6 donors with or without 3 × 10⁵ CD4⁺ cells from WT B6 or CD62L^−/− (B6) donors. *P < .05 for Spl intact versus Spl⁻ recipients of CD4 T cells. (C) On day 0, BALB.B recipients received 850 cGy and 10⁷ BM cells from WT B6 donors with or without 3 × 10⁶ total T cells from WT B6 or CD62L^−/− (B6) donors. NS indicates not significant for recipients of WT versus CD62L^−/− T cells.