Effect of CP-532,903 on fMLP-induced F-actin formation in mouse bone marrow neutrophils. Neutrophils were pretreated with vehicle (A) or 100 nM CP-532,903 (B) for 30 min at 37°C in the presence of 1 unit/ml ADA, and then stimulated with 1 μM fMLP for 30 sec. Cells were stained with FITC-conjugated phalloidin and intracellular fluorescence was quantified by flow cytometry assessing a total of 10,000 cells per sample. Mean ± SEM. *, p < 0.05 versus the vehicle-treated group by Student’s t test, n = 8.