Alpha-1-B glycoprotein (A1BG)

Alpha-1-B glycoprotein is a secreted plasma protein in humans encoded by the A1BG gene. It is composed of 495 amino acids with a molecular weight of about 54 kDa and exhibits sequence and structural similarity to immunoglobulin superfamily proteins, containing four or five immunoglobulin-like domains[1][2][3][5]. Despite extensive study, its precise biological function remains unclear. It binds to cysteine-rich secretory protein 3 (CRISP-3) in plasma, suggesting a protective role against potential CRISP-3 toxicity[1][3]. High A1BG expression has been found in liver, with trace levels in other tissues such as blood, pancreas, and brain[1]. Clinically, A1BG is overexpressed in the pancreatic juice of patients with pancreatic ductal adenocarcinoma, and urinary fragments serve as biomarkers for steroid-resistant nephrotic syndrome[1][3]. Its aberrant expression and processing have also been linked to inflammatory, renal, and autoimmune diseases, although it is not considered a direct therapeutic target or receptor[3][4].

Other names

Alpha-1B-glycoproteinA1BGAlpha-1-B glycoproteinA1BABGGABHYST2477HEL-S-163pAepididymis secretory sperm binding protein Li 163pA