What is the function of factor XIII in hemostasis?

Factor XIII plays a critical role in the final stages of the clotting process by stabilizing fibrin clots through cross-linking fibrin strands. Once fibrin is formed during coagulation, factor XIII (also known as fibrin-stabilizing factor) is activated (usually by thrombin and calcium ions) and catalyzes the formation of covalent bonds between fibrin strands. This cross-linking transforms the initially loose fibrin mesh into a denser and more stable structure, which is essential for a strong and persistent clot that can withstand the forces of blood flow until healing occurs.

This stabilization is crucial for ensuring that the blood clot can effectively seal off the injury site and provide a scaffold for tissue repair. Inadequate functioning of factor XIII can lead to increased bleeding and impaired wound healing, showcasing its importance in the hemostatic process.