Alpha-2-Macroglobulin

Alpha-2-Macroglobulin (A2M) is a large plasma protein found in the blood. It is produced by the liver and is a major component of the alpha-2 globulin protein fraction. It is a potent inhibitor of proteases, preventing their ability to degrade proteins.

Function[edit | edit source]

Alpha-2-Macroglobulin is a broad-spectrum protease inhibitor that binds to and inactivates many different protease enzymes. It is unique among the anti-proteases because it is able to inactivate all types of proteases, including serine proteases, cysteine proteases, aspartic proteases, and metalloproteases. This is accomplished by a 'bait-and-trap' mechanism.

Clinical significance[edit | edit source]

Elevated levels of Alpha-2-Macroglobulin can be found in the blood of individuals with nephrotic syndrome, a condition characterized by proteinuria, hypoalbuminemia, and edema. In this condition, the increased production of Alpha-2-Macroglobulin by the liver is a compensatory response to the loss of smaller proteins in the urine.

In Alzheimer's disease, Alpha-2-Macroglobulin has been found to co-localize with amyloid in senile plaques and is thought to be involved in the clearance of this protein. It has also been implicated in the regulation of the cytokine network in the brain.