title: Antibodies reacting with ribosomal ribonucleoprotein in connective tissue diseases.
abstract: Precipitating antibody to an antigen present in cytoplasm was detected in the sera of 7 patients with systemic lupus erythematosus, 1 patient with an overlap toid arthritis, and 1 patient with mixed connective tissue disease. By physicochemical and enzymatic studies, the antigen was shown to have the properties of ribosomal ribonucleoprotein (gamma-RNP). Cytoplasmic staining in immunofluorescence was observed with all the 9 sera containing antibodies to gamma-RNP. In certain cases, cytoplasmic staining was associated with nucleolar staining. Antibody to gamma-RNP is different in immunologic specificity and clinical significance from antibody to nuclear RNP and is present primarily in patients with systemic lupus erythematosus.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis; D005455:Fluorescent Antibody Technique; D006801:Humans; D005779:Immunodiffusion; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008947:Mixed Connective Tissue Disease / Q000276:immunology*; D009698:Nucleoproteins / Q000276:immunology*; D012261:Ribonucleoproteins / Q000276:immunology*; D012270:Ribosomes / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D009698:Nucleoproteins; D012261:Ribonucleoproteins