Coagulation proteins showing abnormal electrophoretic mobility in commercial concentrates of factor VIII and prothrombin complex.

Five commercial factor VIII (FVIII) concentrates and three prothrombin complex concentrates (PCC) were studied with reference to the qualitative evaluation of factors II, IX, fibronectin, alpha 2-antiplasmin (alpha 2-AP), antithrombin III (AT-III) and subunits A and S of FXIII by crossed-immunoelectrophoresis (CIE) and von Willebrand factor antigen (vWF:Ag) by radio-CIE. This latter protein had a different pattern with the absence or a decrease of larger forms and the presence of a fast-moving precipitating peak, suggesting degradation of the vWF:Ag in FVIII concentrates. In contrast, the electrophoretic mobility of fibronectin, alpha 2-AP and AT-III was normal. All PCC showed a more anodic mobility of factor IX. alpha 2-AP also exhibited a different electrophoretic pattern to that of normal plasma. Abnormality of AT-III was also found in heparin-binding studies. The techniques used in the purification procedures are probably the mechanism responsible for the partial denaturing of these proteins.