CG-mediated sB1^−/− PMN death is cell intrinsic. (A) The relative percentage of cells from each donor is shown for PMNs and B cells from irradiated GFP⁺ mice 8 to 10 weeks after transfer of 1:1 mixture of WT (CD45.1) and sB1^−/− (CD45.2) BM. Data points are indicated for each mouse and means were compared by paired the Student t test (***P < .001). (B) Total PMN numbers in BM of irradiated GFP⁺ mice are shown 8 to 10 weeks after transplant with varying amounts (1:1 or 1:4) of BM cells of WT and sB1^−/− donors relative to the percentage of sB1^−/− input. The dotted line indicates negative correlation between sB1^−/− input and total PMN numbers. (C) The relative percentage of cells from each donor is shown for PMNs and B cells from irradiated GFP⁺ mice 8 to 10 weeks after transfer of 1:1 mixture of WT (CD45.1) and CG.sB1^−/− (CD45.2) BM. Data points are indicated for each mouse and means were compared by the paired Student t test. (D) Survival of WT and sB1^−/− PMNs in vitro in the presence of human CG for 3 hours in serum-free medium. Percentage of live cells (mean ± SD) of 2 to 5 independent experiments were compared by 2-way ANOVA with the Bonferroni posttest.