Alpha-1-proteinase inhibitor


Alpha-1-proteinase inhibitor
Accession Number
DB00058 / F43I396OIS
Alpha1-proteinase Inhibitor (human)

Human alpha-1 proteinase inhibitor or alpha-1-antitrypsin, prepared from human plasma thru Cohn alcohol fractionation accompanied through PEG and zinc chloride fractionation.



Prevents excessive accumulation of active neutrophil elastase and consequent proteolysis of elastin tissues in alveolar lung structures. This prevents the development of emphysema.


For chronic augmentation and maintenance therapy in individuals with alpha1-proteinase inhibitor (A1-PI) deficiency and clinical evidence of emphysema.


Alpha-1 proteinase inhibitor is a serine protease inhibitor (Serpin). Its primary mechanism is inhibiting the action of the serine protease called elastase (also plasmin and thrombin) in the lungs. The reactive center loop (RCL) of alpha-1 proteinase inhibitor extends out from the body of the protein and directs binding to the target protease. The protease cleaves the serpin at the reactive site, establishing a covalent linkage between the carboxyl group of the serpin reactive site and the serine hydroxyl of the protease. The resulting inactive serpin-protease complex is highly stable.