title: Double cryoprecipitated factor VIII concentrate from heparinised plasma and its heat treatment.
abstract: In an attempt to implement the small pool concept in Factor VIII purification, cryoprecipitate derived from heparinised plasma was reprecipitated in the cold providing a factor VIII concentrate for freeze drying and heat treatment. There was considerable purification; only 1% of the original plasma proteins was left in the final product. Factor VIII:C concentration was about 19 IU/ml. Factor VIII related antigen (RAg) appeared heterogeneous, with a broad base and asymmetry on crossed immunoelectrophoresis. Fibrinogen content was 15 g/l. In contrast to high-purity commercial concentrates, fibronectin was considerably concentrated. Immunoglobulin contents were similar to a high-purity commercial product. The amount of other plasma proteins was very small, varying from less than 0.2% for C3 complement to 2.3% ceruloplasmin. In some respects the preparation may be considered as an intermediate-purity Factor VIII concentrate. Following addition of 2% sucrose before freeze drying, Factor VIII, total protein and fibrinogen remain virtually stable (less than 15% loss) during heating of the material to 60, 64 or 68 degrees C for 24 to 72 h without changes of protein spectrum following heating. The heated product when stored at 4 degrees C remains stable for at least 3 months. In two severe haemophiliacs receiving this heat treated product, in vivo Factor VIII recovery was 100% with a mean half life of 10.2 h.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000635:transmission; D011232:Chemical Precipitation; D003080:Cold Temperature; D005169:Factor VIII / Q000032:analysis / Q000627:therapeutic use; D006207:Half-Life; D006467:Hemophilia A / Q000188:drug therapy; D006493:Heparin / Q000494:pharmacology; D006358:Hot Temperature / Q000627:therapeutic use*; D006801:Humans; D010949:Plasma / Q000032:analysis; D012307:Risk Factors; D065227:Transfusion Reaction
chemical_list: D005169:Factor VIII; D006493:Heparin