Identification of 3 PMN serprocidins as protease candidates in cleaving CD11b and promoting PMN transmigration. (A-B) Effects of various serine protease inhibitors (10μM each) on fMLP-induced PMN chemotaxis and CD11b cleavage, respectively. (C) Effects of anti-serprocidin antibodies (50 μg/mL each) and NE inhibitors on PMN transmigration. AEBSF (50μM) was used as positive control. Data are presented as mean ± SD (n = 4). *P < .05; **P < .01.