Correlates between autoantibodies to nucleolar antigens and clinical features in patients with systemic sclerosis (scleroderma).
Immunofluorescence on rat liver sections was used to select high-titer antinucleolar antibodies (ANoA) in the sera of patients with systemic sclerosis (scleroderma). In 646 patients, 53 ANoA sera (8%) were identified, and of these, 46 were available in sufficient quantities for further analysis. The complex of RNA polymerase I was immunoprecipitated by 7 sera (15%), which uniformly produced punctate nucleolar staining. The PM-Scl antigen, a particle consisting of 11 polypeptides, was immunoprecipitated by 8 sera (17%), all of which displayed homogeneous nucleolar staining. A 34-kd nucleolar protein (fibrillarin) of the U3 RNP complex was positive in immunoblotting of 22 sera (48%), which characteristically produced clumpy nucleolar staining. Antibodies against RNA polymerase I were associated with diffuse scleroderma of short duration, which was characterized by a high prevalence of internal organ involvement, including renal crisis. Anti-U3 RNP antibodies had a high prevalence in men with significantly less joint involvement, compared with ANoA-negative patients. Anti-PM-Scl antibodies identified a group of scleroderma patients with a high prevalence of concomitant myositis and renal involvement.
D000974:Antibodies, Antinuclear / Q000032:analysis*; D034961:Antigens, Nuclear; D011232:Chemical Precipitation; D000939:Epitopes; D005455:Fluorescent Antibody Technique; D006801:Humans; D009687:Nuclear Proteins / Q000276:immunology*; D012318:RNA Polymerase I / Q000276:immunology*; D012261:Ribonucleoproteins / Q000276:immunology*; D012595:Scleroderma, Systemic / Q000276:immunology*
D000974:Antibodies, Antinuclear; D034961:Antigens, Nuclear; D000939:Epitopes; D009687:Nuclear Proteins; D012261:Ribonucleoproteins; D012318:RNA Polymerase I