Correlation of sCD52 and WBC or lymph node reductions. (A) Before and during treatment in patients with ‘high risk’ CLL treated with chemo/chemo-immunotherapy in HOVON68 (n = 20, p < .0001). (B) In ‘ibrutinib-treated’ CLL (n = 11, p = ns). (C) Percent lymph node reduction by level of sCD52 at treatment baseline below or equal to (sCD52 low) or above (sCD52 high) sCD523 median in “ibrutinib-treated CLL” patients at 2, 6, and 12 months (n = 25). (D) Levels of sCD52 quantified by western blot in supernatants from anti-IgM bead stimulated and vehicle treated CLL PBMC (n = 4). Statistical analyses were performed by (A–C) linear mixed models and (D) paired t test, (D) data were logarithmically transformed, and (C–D) presented as normalized to pre-values and means with SD are shown. In (C) analysis was made by linear mixed models analyzing differences in lymph node reduction at all three time points in one model.