Vascular P-selectin expression. The number of microvascular structures associated with green (fluorescein-anti–P-selectin) fluorescence was determined in tissue sections (n = 6 per group) of ears from wild-type mice receiving intravenous fluorescein-conjugated control IgG (control Ab) or fluorescein-conjugated anti–P-selectin antibody (selectin Ab). The ears were uninjected, injected with vehicle (phosphate-buffered saline [PBS]), or injected with 400 μg zymosan. *P = .05 versus all other groups.