Anti-interferon-gamma antibodies in sera from HIV infected patients.

High serum levels of antibodies to interferon-gamma (IFN-gamma) have been found in patients infected with human immunodeficiency virus (HIV). A radioimmunoassay (RIA) with a recombinant IFN-gamma protein or an affinity purified IFN-gamma preparation as antigens, was developed to detect the specific anti-IFN-gamma antibodies. Reactivity of sera to IFN-gamma was confirmed by Western blot analysis. These antibodies, however, do not seem to recognize the active site of the molecule, since they do not neutralize the antiviral IFN-gamma activity in a biological assay. These results enforce the hypothesis of the role of autoimmunization during the course of the disease.