Alpha2-macroglobulin is a large protein that is present in plasma. It is synthesized by liver cells and fibroblasts. It’s main functions are the inhibition of proteinases; for example it inhibits plasmin (thus inhibiting fibrinolysis) and thrombin (thus inhibiting coagulation). However, it technically has the ability to inhibit proteases from all catalytic classes, as well as the potential to have its inhibitory function removed (via reaction of it’s thiol ester group with any primary amine group). The main mechanism by which it inhibits proteases is by steric hindrance: when the alpha2-macroglobulin approaches a protease, the protease cleaves the vulnerable region on