IMMUNOCHEMICAL CHARACTERIZATION OF ANTIBODIES TO FACTOR-VIII IN HEMOPHILIC AND NON-HEMOPHILIC PATIENTS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 97  (6) , 791-800
Abstract
Plasma samples from 18 patients (9 hemophilic, 9 nonhemophilic) with antibodies to Factor VIII were purified by [staphylococcal] protein A gel chromatography. This procedure separates the IgG3 from the IgG1, IgG2 and IgG4 subclasses. The partially purified anti-Factor VIII fractions were typed for their H and L chain composition by immunoneutralization assay. Residual anti-Factor VIII activity was revealed by fibrin formation inhibition in agarose gel plates. The combination of these 2 techniques permitted the study of a relatively large number of partially purified samples, at several dilutions of each, against each anti-H or anti-L chain antiserum obtained from various sources. A high degree of subclass and L chain restriction was found in the antibodies from the hemophilic patients, 8 were predominantly of IgG4 .kappa. type, the 9th was IgG4 but of mixed L chains. A heterogeneous distribution was found in the 10 nonhemophilic patients: 2 IgG4 .kappa. 1 IgG4 .lambda., 1 IgG4 with both .kappa. and .lambda., 2 a mixture of IgG1 and IgG4 with only .kappa. L chains, and 3 a mixture of IgG1 and IgG4 as well as both L chains.