Effect of endogenous IL-8 inhibition by antisense oligonucleotides or neutralizing antibody on CD34⁺-derived cell proliferation. CD34⁺ cells purified from patients with MMM or NPB were cultured for 14 days in serum-free medium containing a cytokine cocktail (as described in “Materials and methods”) with or without IL-8 antisense (5 μM, panel A) or antihuman IL-8 antibody (10 μg/mL, panel B). Cells were harvested after 14 days of culture and counted. Bar graphs display mean ± standard error of the mean (SEM) from 3 independent experiments for normal PB. patients with MMM were individually analyzed.