title: Anti-interferon-gamma antibodies in a patient undergoing interferon-gamma treatment for systemic mastocytosis.
abstract: An 81-year-old woman with systemic mastocytosis responded to subcutaneous recombinant interferon-gamma (rIFN-gamma) treatment for about 6 months, when intestinal symptoms gradually recurred. A serum sample obtained 3 months later was positive for specific rIFN-gamma-binding antibodies, which had been absent at the initiation of treatment. Cessation of IFN-gamma therapy was followed by a slow decline of IFN antibody titers. The IFN-gamma antibodies were of polyclonal or oligoclonal origin, with a predominance of IgG1 and IgG2 and small amounts of IgA and IgM. They neutralized the antiviral activity of both rIFN-gamma and, less efficiently, natural IFN-gamma in vitro. The time course of the neutralizing titers paralleled the IFN-binding activity of the antibodies. Thus, like other cytokines, rIFN-gamma may be immunogenic in rare patients and elicit the formation of neutralizing antibodies that may impair the therapeutic activity of the drug and interfere with the endogenous IFN-gamma system.
authors.affiliation: Department of Medicine III, University of Ulm, Germany.
authors.forename: O
authors.initials: O
authors.lastname: Prümmer
authors.forename: C
authors.initials: C
authors.lastname: Fiehn
authors.forename: H
authors.initials: H
authors.lastname: Gallati
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000937:Antigen-Antibody Reactions; D001667:Binding, Competitive; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007136:Immunoglobulins / Q000097:blood*; D007371:Interferon-gamma / Q000276:immunology / Q000627:therapeutic use*; D008415:Mastocytosis / Q000188:drug therapy* / Q000276:immunology; D011994:Recombinant Proteins
chemical_list: D007136:Immunoglobulins; D011994:Recombinant Proteins; D007371:Interferon-gamma