Fig. 3

CXCR4 antibody-induced cell death is dependent on CXCR4-expression and independent of CLL disease risk factor or stromal presence. a CXCR4 expression profiling was done using an anti-CXCR4 antibody for staining in the MEC1 cell line and primary CLL-B cells from a representative patient, followed by analysis using flow cytometry. The CXCR4 expression is presented in ∆MFI. b MEC1 and CLL-B cells were treated with different concentrations of m15-IgG1 (2–2000 nM) or IgG1 control antibody, for 48 h followed by flow cytometry analysis to determine % SICD. Samples were tested in duplicates, with the mean and standard deviation shown for each group. c The CLL-B cells derived from a CLL patient were treated with either F-ara-A (3 and 10 μM), AMD3100 (4 and 40 μM), IgG1 control antibody, or m15-IgG1 antibody, in presence or absence of stroma NK-tert cells, for 48 h followed by analysis using flow cytometry. The results of samples analyzed in duplicates with the mean ± SD are shown for each group. d Primary leukemia CLL-B cells were obtained from CLL patients, with high-risk or low-risk phenotypes, or carrying TP53 17pDel mutation (n = 10 per group). Normal B and T lymphocytes were obtained from healthy donors (n = 10 per group). The % SICD was determined after treatment with 100 nM of m15-IgG1 for 48 h. The figure shows the mean ± SD for % SICD in different cell types. Statistical significance was determined using Bonferroni’s correction test for multiple comparison tests, where *, **, ***, and **** represent p < 0.05; p < 0.01, p < 0.001, and p < 0.0001, respectively