Partial Purification and Characterization of Factor VIII-Activity Present in the Supernatant of Cryoprecipitates

A relative higher percentage of the initial factor VIII activity is found in the supernatant of plasma from patients with von Willebrand’s Disease than in that from normals after cryoprecipitation. Moreover no factor VIII related antigen can be demonstrated in the supernatant after cryoprecipitate. A further study of the characteristics of this cryo-supernatant-factor VIII seemed therefore of interest.

Cryosupernatant-factor VIII was partially purified by poly ethyl enegly col and ammoniumsulfate precipitation, followed by Sepharose 6B gelfiltration. Cryosupernatant-factor VIII was eluted at the void volume of Sepharose 6B columns, but in contrast to cryoprecipitated factor VIII it was retarded on Sepharose 2B columns.

Cryosupernatant-factor VIII has antigenic determiniant(s) in common with normal factor VIII.

Von Willebrand plasma’s obtained 6 to 40 hours after transfusion with normal cryoprecipitate were applied to gelchromatography on Sepharose 6B columns. The factor VIII activity was eluted at the void volume. On Sepharose 2B the elution pattern of the factor VIII activity was comparable to that of normal plasma.