title: Identification of human anti-DNA, anti-RNP, anti-SM, and anti-SS-A serum antibodies bearing the cross-reactive 16/6 idiotype.
abstract: The human idiotype 16/6, characteristic of lupus-derived anti-DNA autoantibodies, was detected in sera of Japanese patients with autoimmune diseases. The 16/6-positive sera were from patients with active SLE and, in one case, a scleroderma-polymyositis overlap syndrome; all contained anti-ssDNA antibody. Affinity chromatography was used to isolate 16/6-bearing Ig from sera of seven patients having anti-DNA and other autoantibodies. In a preliminary step, rheumatoid factors and nonspecific binding were removed by four passes of the serum through a column of immobilized normal rabbit gamma-globulin. The absorbed sera were then applied to a column of immobilized specific rabbit anti-16/6 globulin. This combined procedure depleted anti-ssDNA activity selectively. From 44 to 60% of total Ig but only 6 to 25% of anti-ssDNA activity was recovered in the material that passed through both columns. Approximately 40% of the anti-RNP/Sm and anti-SS-A/SS-B activities were recovered, reflecting a lesser degree of selective depletion of these antibodies. The specific eluate from the anti-idiotype column contained more IgG than IgM; anti-DNA activity; anti-RNP, anti-Sm, or anti-SS-A activity. Soluble DNA inhibited the binding of one eluate to RNP/Sm but not of another eluate to SS-A/SS-B. The results confirm that the genes encoding the 16/6 idiotype are widely represented in ethnically different human populations, and indicate that 16/6-bearing Ig may bind to other autoantigens as well as to DNA.
authors.forename: J
authors.initials: J
authors.lastname: Kaburaki
authors.forename: B D
authors.initials: BD
authors.lastname: Stollar
mesh_terms: D001323:Autoantibodies / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D003429:Cross Reactions; D004247:DNA / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology; D007163:Immunosorbent Techniques; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D020733:RNA, Small Cytoplasmic; D012261:Ribonucleoproteins / Q000276:immunology*; D017411:Ribonucleoproteins, Small Nuclear; D012595:Scleroderma, Systemic / Q000276:immunology; D055517:snRNP Core Proteins; D000099207:SS-A Antigen
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D004247:DNA; D007074:Immunoglobulin G; D007130:Immunoglobulin Idiotypes; D007075:Immunoglobulin M; D020733:RNA, Small Cytoplasmic; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D055517:snRNP Core Proteins; D000099207:SS-A Antigen; C116006:RO60 protein, human