Allogeneic SCT with RANTES-deficient donor cells results in significantly decreased IPS severity. Lethally irradiated B6D2F1 mice received SCT from either syngeneic B6D2F1 (□), or allogeneic B6 wild-type (▪) or B6 RANTES-/- (▦) donors. Animals that received transplants were analyzed at 4 and 6 weeks after SCT. (A) Photomicrographs of lung tissue 6 weeks after SCT (HE; × 200). (B) Lung injury as assessed by a semiquantitative scoring index at 4 and 6 weeks after SCT. Data are presented as mean ± SEM and are combined from 2 comparable experiments at week 6 (n = 9 to 11 per group; ^*P < .01) or from 1 experiment at week 4 (n = 4-8 per group; ^*P < .05). BALF cellularity (C), CD4⁺ T cells (D), CD8⁺ T cells (E), monocytes/macrophages (F), and GR-1⁺ cells (G) 4 and 6 weeks after SCT. Data are expressed as mean ± SEM and are either combined from 2 comparable experiments (n = 9 to 11 per group) at week 6 or from 1 experiment (n = 4 to 8 per group) at week 4; ^*P < .05.