Figure 9.

Effect of treatment with rolipram and Bt₂cAMP on human neutrophil apoptosis. Neutrophils isolated from human peripheral blood (1 × 10⁶ cells/well) were cultured with LPS (500 ng/ml) for 1 h and later with ROL (100 μm), Bt₂cAMP (100 μm) (A and D–F), or different concentrations (B and C). The cells were also pretreated with anti-AnxA1 antiserum (100 μg/ml) or WRW4 (10 μm), a specific FPR2/ALXR antagonist, 1 h before LPS (D, E, and F). Sivelestat (100 μg/ml) was used as a positive control for neutrophil apoptosis (A). Neutrophils were processed for cytospin preparations for apoptosis count. Representative figures of nonapoptotic (asterisks) and apoptotic (arrows) neutrophils are shown (original magnifications, ×100). **, p < 0.01; ***, p < 0.001 when comparing the LPS-treated group with untreated (UT) neutrophils. #, p < 0.05; ##, p < 0.01; ###, p < 0.001 when comparing the LPS-treated group with drug-treated neutrophils. The experiments were performed in biological quadruplicates. Error bars, S.E.