Elastase release from neutrophils adherent to platelet monolayers in the presence of 10⁻⁷ mol/L fMLP (Control) and an MoAb against either P-selectin (Anti-P-sel), CD18 (Anti-CD18), or CD11b (AntiCD11b). Data are the mean ± SEM from three experiments. Paired t-test showed that elastase release from cells in the presence of CD18 or CD11b antibodies was significantly lower (*P < .05) than in untreated control cells.