Neutrophil passage through microcapillaries. The purified human neutrophils were incubated with HBSS, HSA (1 μM), IAIPs (100 and 200 μg/mL), or bikunin (100 and 200 μg/mL) for 30 minutes and then applied to an MC-FAN. (A) The time required for the passage of 100-μL neutrophil suspension through the MC-FAN was determined (supplemental Video 1). The results shown are the means ± SEM of 5 experiments. **P < .01 vs HBSS; ##P < .01 vs HSA. (B) Red arrowheads indicate the leukocytes attached to the upper chamber. Yellow arrowheads indicate the leukocytes attached to the microcapillary entrance or slit (scale bars, 30 μm). NS, not significant compared with both HBSS and HSA groups.