SERPINA3 is A subtype A of the serine protease inhibitor family, consisting of 423 amino acids, including A signaling peptide at the nitrogen end and A serpin domain with serine protease inhibitor activity. There are multiple glycosylation sites, and the total relative molecular weight is 55 * 103~66 * 103. SERPINA3 has been reported to be associated with inflammatory reactions, alzheimer's disease, malignant melanoma, gastric cancer, and colon cancer.