CD49d expression over time. CD49d expression was evaluated in 2 sequential samples from 94 CLL cases with CD49d bimodal expression either untreated (n = 52; A) or treated once between the samples (n = 42; B). (C) Variation of the amount of CD49d⁺ cells in sequential samples from 13 CD49d bimodal CLL treated with 2 lines of therapy (n = 3; blue symbols), 3 lines of therapy (n = 6; green symbols), or 4 lines of therapy (n = 4; red symbols). Each symbol corresponds to a different case; P values refer to the paired Wilcoxon test (A-B) and to the Bonferroni-corrected Student t test (α = 0.0125).