Effect of endogenous IL-8 inhibition by antisense oligonucleotides or neutralizing antibody on CD41 antigen expression levels. CD34⁺ cells purified from either MMM or NPB were cultured in serum-free medium containing a cytokine cocktail in the presence and absence of 5 μM IL-8 antisense (panel A) or 10 μg/mL antihuman IL-8 antibody (panel B). Cells were harvested after 14 days of culture and labeled with monoclonal antibody against CD41. The percentage (▪) and MFI () of CD41⁺ cells were analyzed with Cellquest software by means of a FASCcalibur flow cytometer. Bar graphs display mean ± SEM from 3 independent experiments. patients with MMM were individually analyzed.