Alpha-1-acid glycoprotein (AGP)

Alpha-1-acid glycoprotein (AGP; orosomucoid) is a highly glycosylated acute-phase plasma protein, primarily produced by the liver but also expressed in other tissues. It comprises two isoforms in humans (AGP1 and AGP2, encoded by ORM1 and ORM2 genes) and features a lipocalin beta-barrel structure that affords broad ligand-binding capacity. AGP rises substantially during inflammation, infection, tissue injury, pregnancy, or estrogen therapy, with glycosylation pattern and proteoform diversity influencing its biological activities. Its main physiological functions are regulation of immune responses—especially dampening excessive inflammation—transport of basic and neutral lipophilic drugs and hormones, and possible roles in metabolic regulation. AGP's drug-binding profoundly affects pharmacokinetics and pharmacodynamics, and serum AGP levels are often monitored clinically as markers of inflammation and for dose adjustment of AGP-bound drugs.

Other names

OrosomucoidOrosomucoid-1AGP 1AGP1OMD 1

Drug sequestration via high-affinity binding Modulation of free and bioactive drug concentrations