Autoantibodies against human beta interferon following treatment with interferon

Recently we reported the appearance of human beta interferon (HuIFN-beta) neutralizing antibodies in a patient with a nasopharyngeal carcinoma treated successfully with a preparation of HuIFN-beta. This was the first report presenting evidence for antigenicity of IFN in an homologous system. In the present report we asked whether the unusual appearance of antibodies was due to a genetic defect of the patient's cells to produce HuIFN-beta or whether the patient's cells produce an antigenically different variant of HuIFN-beta. We demonstrate that a fibroblast cell strain established from this patient produces HuIFN-beta which does not from a serological standpoint react differently from the HuIFN-beta preparation administered. The conclusion is drawn that the antibodies against therapeutic HuIFN-beta are reacting like autoantibodies with the patient's own HuIFN-beta.