Characteristics of the von Willebrand factor in virus inactivated F VIII concentrates: the impact of heat treatment.
The known transmission of viral diseases, particularly AIDS (HIV, LAV, HTLV-III), has led to the mandatory use of virus-inactivated coagulation factor concentrates for treatment of bleeding disorders due to deficient or abnormal synthesis of the factor VIII/von Willebrand factor complex. The present investigation was undertaken to study the influence of heat-treatment on the von Willebrand factor (vWf). Using normal plasma as reference material, we studied the influence of low-purification steps in a simple cryo-plasma and a unrefined freeze-dried cryoprecipitate. For comparison, non-heated and heat-inactivated concentrates of different manufacture representing varying heat-treatment protocols were studied using quantitation of von Willebrand factor antigen (vWf:Ag) by electroimmunoassay and ELISA, and investigation of vWf multimeric composition. A locally produced factor VIII concentrate was studied before and after exposure to 68 degrees C for 72 hours (dry state). Whenever possible, commercial preparations manufactured prior to the heat-treatment era were compared with the present product. The locally produced high purity concentrate elicited only minor changes in oligomeric satellite pattern, which did not change after dry heat exposure. In principle, no major differences were found between non-heated and pasteurized commercial concentrates of same manufactural origin.
D000941:Antigens / Q000032:analysis; D001793:Blood Preservation / Q000379:methods*; D003101:Collodion; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005169:Factor VIII / Q000032:analysis*; D005260:Female; D005612:Freeze Drying; D006358:Hot Temperature; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D011487:Protein Conformation; D014841:von Willebrand Factor / Q000032:analysis*
D000941:Antigens; C029417:Von Willebrand antigen; D014841:von Willebrand Factor; D005169:Factor VIII; D003101:Collodion