BLOOD clotting is a host defense mechanism that, in parallel with the inflammatory and repair responses, helps protect the integrity of the vascular system after tissue injury. This system is normally quiescent but becomes active within seconds after injury. Cells (platelets, leukocytes, and endothelial cells) and the plasma blood-clotting proteins are critical in this reaction. The response to vascular injury culminates in the formation of a platelet plug, the generation of a fibrin clot, the deposition of white cells in the area of tissue injury, and the initiation of inflammation and repair.

Molecular Basis of Blood Coagulation

All the protein . . .