Combination of anti-CCL2 and venetoclax increased sensitivity of CMD CLL toward apoptosis. (A) Upper, delta priming measurement of CLL samples treated with either anti-CCL2 (1 μg/mL) alone for 48 hours, venetoclax (0.5 nM) alone for 1 hour, or with venetoclax + anti-CCL2 cultured in presence of CM. Delta priming was calculated from before and after treatment in response to BIM, BAD, and HRK peptides. (CMD, n = 5; CMI, n = 3). Lower, Comparison of delta priming among treatments. Each point represents a CLL sample. Data are means ± standard error of the mean. P values were calculated using 1-sided t test followed by a Bonferroni correction, and P value < .05 indicates statistically significance. (B) Cell viability of primary CLL samples was measured 48 hours after treatment with anti-CCL2, venetoclax, or anti-CCL2 + venetoclax cultured in CM (n = 4) independent samples for each group (CMD = patient #1, 2, 3, and 7 and CMI = patient #20, 21, 22, and 23), Error bars represent standard error of the mean. P values were calculated using 2-way analysis of variance, and P value < .05 indicates statistical significance.