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How do coagulation and fibrinolytic systems contribute to inflammation?

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Pathways of complement activation — inflammation The main function of complement proteins is to aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages (a process known as opsonization). Some complement components also promote inflammation by stimulating cells to release histamine and by attracting phagocytic cells to the site of infection.

The coagulation and fibrinolytic systems are two of the four interrelated plasma protein systems that generate chemical mediators during the inflammatory response.1

The Coagulation System

The coagulation system contributes to inflammation by converting the plasma protein fibrinogen into fibrin, which serves as a major component of the fluid exudate at the site of injury. Additionally, the activation of coagulation factor XII triggers the kinin system, which produces substances like bradykinin that increase vascular permeability and are responsible for much of the pain and itching associated with inflammation.1

The Fibrinolytic System

The fibrinolytic system contributes to the inflammatory process primarily through the formation of plasmin. Plasmin functions by breaking down fibrin into degradation products that further influence vascular permeability, thereby modulating the inflammatory response.1

Together, these systems ensure that the body’s response to injury involves not only the physical sealing of damaged vessels but also the active release of chemical signals that regulate the progression of inflammation.12