In the process of isolation of factor VIII from human plasma making use of immunoadsorbents prepared by coupling monoclonal murine antibodies to resins, trace amounts of murine immunoglobulin G (IgG) antibodies are released from the resin into the final Monoclate® product. This trace contamination, amounting to not more than 50 ng 100 units of Monoclate®, was assumed to be below the threshold amounts necessary for inducing an immune response. Nevertheless, we have developed a series of highly sensitive and specific radioimmunoassays for the determination of human antibodies of the IgG, IgM, and IgE classes against the murine monoclonal IgG used for purification of Monoclate®. Screening of sera from adults and children treated with Monoclate® showed that in no case were any antibodies produced in response to injection of Monoclate®. Surprisingly, sera from several patients had a high activity against murine IgG both before and after treatment with Monoclate®.
|Number of pages||5|
|Journal||Seminars in Hematology|
|Issue number||2 SUPPL. 2|
|State||Published - Apr 1990|