The factor VIII complex: structure and function.

Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIII-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical properties, and have unique and essential physiologic properties. While the nature of their interaction and the details of their biochemical structure remain to be determined, the information now available permits a preliminary understanding of the molecular defects in the factor VIII deficiency disease.