CD4/CD8 reconstitution after Alem/TBI/Cy, compared with that after TBI/Cy and auto-SCT. (A) CD4 and CD8 counts (per microliter) and CD4/CD8 ratios at different time points after SCT for patients receiving Alem/TBI/Cy (n = 16) (▪) and patients receiving TBI/Cy (University of Ulm and Kiel) (n = 14) (□). P values (t test) at different time points are shown if they are lower than .05. Patients in the Alem/TBI/Cy group experienced severe depletion of CD4 and CD8 cells with a highly abnormal CD4/CD8 ratio in the first year after SCT caused by severe CD8 lymphopenia. As shown in panel B, the difference was caused by the severe depletion of CD8 cells (hence the high CD4/CD8 ratio) in patients with auto-GVHD. (B) CD4 and CD8 counts (per microliter) and CD4/CD8 ratios at different time points after SCT for patients receiving Alem/TBI/Cy who acquired GVHD (n = 7) (•) and patients receiving Alem/TBI/Cy who did not acquire GVHD (n = 9) (○). P values (t test) at different time points are shown if they are lower than .05. Although the differences in CD4 cell counts were not significant, differences in CD8 counts and CD4/CD8 ratios were highly significant at different time points in the first year after SCT. Bars represent mean value.