Hemopexin (also known as β 1B glycoprotein or HPX), a 462 amino acid protein, functions as a scavenger and transporter of toxic plasma heme, transporting heme to the liver for breakdown and iron recovery. Hemopexin cooperates with Albumin, Haptoglobin, and high and low density lipoproteins to trap toxic plasma heme, which occurs as the result of the degradation of hemoglobin, myoglobin and enzymes with heme prosthetic groups, and to ensure the clearance of toxic heme from the plasma. After releasing the heme molecule, the free Hemopexin returns to circulation. It is expressed by the liver and is secreted in plasma. Hemopexin may play a role in the maintenance of metal ion homeostasis. It binds the following metal ions in order of highest to lowest affinity: nickel, copper, cobalt, zinc and manganese. Hemopexin can also act as a toxic protease that leads to proteinuria and glomerular alterations, which are characteristics of minimal changes disease (MCD), a common cause of nephrotic syndrome.