title: Antibodies against Ku protein in sera from patients with autoimmune diseases.
abstract: Immunoaffinity-purified Ku protein was used to screen sera from patients with systemic lupus erythematosus (SLE), scleroderma, myositis and Sjögren's syndrome for anti-Ku antibodies in a quantitative immunoblot assay. Sixteen percent of the 159 studied sera were reactive with the Ku protein; significantly increased frequencies of anti-Ku antibodies were found in SLE (19%) and scleroderma (14%) sera. Patients with myositis and Sjögren's syndrome showed similar frequencies. All positive sera had antibodies to the 86 kD subunit of Ku protein; only one serum did not react with 70 kD subunit. Frequencies of other autoantibodies were compared in anti-Ku positive and negative patients. Only anti-Sm antibodies, especially in the absence of anti-nRNP, appear to be associated with the presence of anti-Ku antibodies. A strong correlation between anti-Ku antibodies and the class II HLA antigen DQw1 (89% of the positive sera) was observed, suggesting participation of MHC genes in the mounting of the anti-Ku immune response.
authors.affiliation: Department of Pharmacology, Baylor College of Medicine, Houston, TX 77030.
authors.forename: M
authors.initials: M
authors.lastname: Yaneva
authors.forename: F C
authors.initials: FC
authors.lastname: Arnett
mesh_terms: D034961:Antigens, Nuclear; D000954:Antigens, Surface / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology*; D004265:DNA Helicases; D004268:DNA-Binding Proteins / Q000276:immunology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting; D007123:Immunoelectrophoresis, Two-Dimensional; D000072200:Ku Autoantigen; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000276:immunology; D008297:Male; D009220:Myositis / Q000175:diagnosis / Q000276:immunology; D012595:Scleroderma, Systemic / Q000175:diagnosis / Q000276:immunology; D012859:Sjogren's Syndrome / Q000175:diagnosis / Q000276:immunology
chemical_list: D034961:Antigens, Nuclear; D000954:Antigens, Surface; D001323:Autoantibodies; D004268:DNA-Binding Proteins; D004265:DNA Helicases; C106893:XRCC5 protein, human; C000606509:Xrcc6 protein, human; D000072200:Ku Autoantigen