Studies on the response of patients with classic hemophilia to transfusion with concentrates of antihemophilic factor. A difference in the half-life of antihemophilic factor as measured by procoagulant and immunologic techniques.
Antihemophilic factor (AHF, factor VIII) levels were measured by a standard coagulation method and by an immunologic technique before and after infusion of AHF concentrates into patients with classic hemophilia. After infusion of AHF concentrates, the half-life of the AHF procoagulant (i.e., clot-promoting) activity varied from 12 to 14 hr, whereas that of the antigen ranged from 24 to 40 hr. The half-life of the antigen was similar in patients with and without circulating anticoagulants to AHF. The data are compatible with the suggestion that the antigen may be carried on a precursor molecule which the patient with hemophilia produces but cannot convert to the functional clot-promoting agent. Other explanations of the observations are, however, recognized.
D000328:Adult; D000818:Animals; D000941:Antigens / Q000032:analysis; D001777:Blood Coagulation / Q000187:drug effects; D005169:Factor VIII / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology / Q000627:therapeutic use*; D006207:Half-Life; D006467:Hemophilia A / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D006801:Humans; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D007263:Infusions, Parenteral; D007700:Kinetics; D008297:Male; D011817:Rabbits / Q000276:immunology
D000941:Antigens; D005169:Factor VIII