Heterogeneity of haemophilia A: a study with three different antisera.
One human and one rabbit antibody against VIII:C--in a fluid-phase, inhibitor neutralization assay (INA)--and one human antibody--in a solid-phase, immunoradiometric assay (IRMA)--were used to investigate a group of 59 patients with severe, moderate and mild haemophilia A. Patients were classified as haemophilia A+ when the VIII:C/VIIIAG ratio was less than 0.4 while the absolute VIII:C antigen (VIIICAG) value exceeded 0.25 u/ml. Three haemophiliacs (from two pedigrees) were classified as A+ in all three assay systems. 50% of the patients were classified as haemophilia A+ on the basis of at least one assay. The other 50%, including 66% of the patients with severe haemophilia, were shown to be A- by all three assay systems. Combining the data obtained with the three different antibodies four different categories could be distinguished, in addition to the classification based on severity.
D000941:Antigens / Q000032:analysis*; D005169:Factor VIII / Q000032:analysis / Q000276:immunology*; D006467:Hemophilia A / Q000097:blood* / Q000145:classification / Q000276:immunology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D009500:Neutralization Tests; D011863:Radioimmunoassay
D000941:Antigens; D007106:Immune Sera; D005169:Factor VIII