THE ROLE OF HUMAN COAGULATION FACTORS IN SERUM-INDUCED THROMBOSIS *

Abstract

Utilizing the rabbit assay (J. Appl. Physiol. 14, 943, 1959) as a quantitative measure of the serum thrombotic accelerator (STA) activity of human serum, STA activity of normal human sera was compared with that of sera obtained from patients with known heredofamilial coagulation defects. Human sera obtained from patients deficient in Factor V (ac-globulin), Factor VII (converting Factor VIII (antihemophilic factor), or Factor X ("Stuart" factor) contain normal STA activity. In striking contrast, sera from patients deficient in Factor IX (PTC) or Hageman factor are essentially devoid of STA activity. Finally, sera from patients deficient in plasma thrombo-plastin antecedent (PTA) have a significantly less than normal but measurable quantity of STA activity. The technic of serum-induced thrombosis provides a reproducible, physiologic method for defining the possible role of coagulation factors in the formation of intravascular thrombi.