[Factor XIII and endothelial barrier function].

Activated factor XIII (FXIIIa) crosslinks fibrin monomers to a stable clot. Due to this function, FXIIIa plays a major role in hemostasis and fibrinolysis. Additionally, it is well known that FXIIIa has a special meaning in cell adhesion and migration, in generation of extracellular matrix, in tissue repair and wound healing. New experimental studies revealed a FXIIIa stabilizing endothelial barrier function. In this function, FXIIIa reduces endothelial permeability for macromolecules in cultured endothelial monolayers and prevents impending barrier failure in coronary arteries of isolated hearts. This effect is due to the cross-linking of several proteins within the extracellular matrix, especially in the interendothelial clefts.