Hemopexin (HPX)

Hemopexin (HPX) is a **plasma glycoprotein** primarily synthesized in the liver, with the highest known binding affinity for **free heme**. It functions as a crucial scavenger of heme released during turnover or pathological breakdown of hemoproteins (such as hemoglobin) in hemolytic and inflammatory conditions[2][4][5]. By binding free heme and delivering it to specific cellular receptors (notably CD91/LRP1 on hepatocytes and macrophages), HPX prevents heme's pro-oxidant and pro-inflammatory actions and promotes its detoxification via heme catabolism (e.g., to biliverdin, carbon monoxide, and iron)[4][5]. HPX is an important **acute-phase reactant**, with plasma levels increasing in response to inflammatory signals. HPX is not a direct drug target or receptor; rather, it plays an essential physiological and protective role in heme and iron homeostasis and the prevention of oxidative tissue injury during hemolytic crisis[2][4][5].

Other names

HemopexinHPXBeta-1B-glycoproteinHXbeta-1B-glycoproteinepididymis secretory sperm binding proteinhemopexin

Not applicable for drugs, but as a molecule: Binds free heme with high affinity, transports and delivers it for cellular uptake via heme-hemopexin receptors (e.g., CD91/LRP1), which facilitates detoxification and protection against oxidative damage[2][3][4][5].