Prevalence and functional role of anti-IgE autoantibodies in urticarial syndromes.
The prevalence of autoantibodies of immunoglobulin G (IgG) and immunoglobulin M (IgM) classes directed against myeloma immunoglobulin E (IgE) were determined in distinct subsets of urticaria, using an enzyme immunoassay. IgG anti-IgE antibodies were found in five of nine patients (55%) with cold urticaria, four of eight patients (50%) with urticarial vasculitis, and three of six patients (50%) with chronic urticaria. IgM anti-IgE antibodies were found exclusively in cold urticaria (two of nine patients, 22%). Heating of these sera increased the binding to IgE, suggesting immune complex formation. Several positive sera were capable of inducing histamine release from normal peripheral basophils and caused a wheal-flare response upon intradermal injection. Sera containing such autoantibodies from three cold urticaria patients were studied for passive transfer of cold sensitivity. One serum containing IgG anti-IgE gave a strongly positive transfer test at 5 h but not 48 h, suggesting a pathogenic role for the IgG.
D000888:Antibodies, Anti-Idiotypic / Q000032:analysis*; D001323:Autoantibodies / Q000032:analysis* / Q000502:physiology; D001491:Basophils / Q000378:metabolism; D003080:Cold Temperature; D006636:Histamine Release; D006801:Humans; D007124:Immunoenzyme Techniques; D007073:Immunoglobulin E / Q000276:immunology*; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D014581:Urticaria / Q000276:immunology*
D000888:Antibodies, Anti-Idiotypic; D001323:Autoantibodies; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007073:Immunoglobulin E