An Attachment Point for Thrombin

Thrombomodulin is a protein found on the surface of cells lining the blood vessels. It acts as an attachment point for thrombin and plays an important role in blood clotting and clot breakdown. Thrombomodulin-bound thrombin initiates the protein C anticoagulant pathway by activating protein C.

Defects in thrombomodulin result in increased clotting. Thrombomodulin also activates the thrombin-activated fibrinolysis inhibitor, which affects clot breakdown. Small thrombomodulin pieces circulate in the plasma of healthy individuals. These pieces retain their activity and can be measured in plasma using a laboratory test.

Increased levels are seen in patients with venous and arterial clotting conditions, including clots in the brain and eyes, and DIC. The impact of thrombomodulin levels in treating clotting disorders is not fully known.