Thrombin–fibrinogen complex

The Thrombin–fibrinogen complex represents the essential biochemical interaction between the serine protease thrombin (activated Factor II) and its primary substrate, fibrinogen (Factor I), which constitutes the final step of the blood coagulation cascade [1, 15]. Thrombin catalyzes the conversion of soluble fibrinogen into insoluble fibrin by cleaving fibrinopeptides A and B from the N-terminal regions of the fibrinogen alpha and beta chains [12, 18]. This process triggers the polymerization of fibrin monomers into a stable meshwork that forms the structural basis of a blood clot, a process vital for hemostasis but also central to pathological thrombosis [4, 8]. Dysregulation of this interaction is implicated in various cardiovascular and inflammatory diseases, including deep vein thrombosis, pulmonary embolism, and stroke [2, 3]. Therapeutic strategies often focus on inhibiting this interaction using direct thrombin inhibitors (DTIs) like dabigatran or bivalirudin, which prevent clot formation by blocking thrombin's catalytic activity or its binding to fibrinogen [14, 16]. Conversely, the two components are co-administered in topical fibrin sealants to promote rapid hemostasis and tissue sealing during surgical procedures [6, 9].

Other names

Thrombin-fibrinogen interactionFactor IIa-Factor I complexF2-FGA/FGB/FGG interactionThrombin-fibrinogen axis

Direct thrombin inhibitors (DTIs) bind to thrombin's active site or exosite I to prevent the cleavage of fibrinogen into fibrin [14, 16]. Fibrin sealants provide exogenous thrombin and fibrinogen to mimic the final step of the coagulation cascade for topical hemostasis [6, 9].