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.
Bruce Bennett, Oscar D. Ratnoff
The Editorial Board will only consider comments that are deemed relevant and of interest to readers. The Journal will not post data that have not been subjected to peer review; or a comment that is essentially a reiteration of another comment.