Proteinase 3 is one of the serine proteinases localized in azurophil granules of polymorphonuclear leukocytes. It has been identified as the autoantigen of Wegener granulomatosis, a systemic vasculitis complicated by melomonocyte proliferation.
Prepared from whole blood shown to be non reactive for HBsAg, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA-required tests.
Serine protease that degrades elastin, fibronectin, laminin, vitronectin, and collagen types I, III, and IV (in vitro). By cleaving and activating receptor F2RL1/PAR-2, enhances endothelial cell barrier function and thus vascular integrity during neutrophil transendothelial migration. Plays a role in neutrophil transendothelial migration, probably when associated with CD177. Triggers inflammatory processes in neutrophils by interacting with ADGRG3 upstream of F2RL1/PAR2 activation. Catalytic activity: Hydrolysis of proteins, including elastin, by preferential cleavage: -Ala-|-Xaa- > -Val-|-Xaa-.Activity regulation: Inhibited by phenylmethanesulfonyl fluoride (PMSF) and diisopropyl fluorophosphate (DFP). pH Dependence: Optimum pH is 7.4.