Fig. 4

IQS019 interferes with malignant B cell chemotaxis. Representative, CXCR4-expressing B lymphoid cell lines (a) and a set of n = 7 CLL primary samples (b) were exposed for 1.5 h to 1 or 2.5 μM IQS019, with or without Ig-mediated BCR stimulation, followed by cytofluorimetric recounting of cells migrated towards recombinant CXCL12 in a 4-h transwell assay. Treatment with the CXCR4 antagonist AMD3100 (40 μM) was used as a control of chemotaxis blockade. Expressed are the ratios between CXCL12-dependent and CXCL12-unspecific migration. c Cell migration profiles from two representative CLL cases are shown. d A set of six CLL cultures were treated as above with CXCL12 +/- IQS019 and stained with phalloidin-TRITC. Cells with high levels of polymerized F-actin were recounted for each condition by two independent reviewers. Shown are the mean results obtained from the six cases. Statistical significance: * p < 0.05, ** p < 0.01, *** p < 0.001