title: Binding of anti-double stranded (ds) DNA-positive sera to denatured (d) DNA and synthetic poly[dA-dT] x poly[dA-dT] double stranded copolymer in an ELISA format.
abstract: Using an ELISA assay anti-nuclear antibody-positive sera from 300 patients with various immune-related diseases and 64 anti-nuclear antibody-negative sera were analysed for binding to S1-nuclease-treated double stranded (ds) DNA. In addition, the pattern of reactivity of 50 selected anti-dsDNA-positive sera was established using denatured (d) DNA and poly[dA-dT] X poly[dA-dT] double-stranded alternating copolymer (dAT) as additional DNA antigens. None of the 64 anti-nuclear antibody-negative sera and 76 of the 300 anti-nuclear antibody-positive sera (25%) were anti-dsDNA-positive. Of the anti-nuclear antibody-positive and anti-dsDNA-positive sera, 48 (63%) were from systemic lupus erythematosus patients, and 7 (9%) from rheumatoid arthritis patients, whereas 21 patients (27.6%) suffered from various immune and non-immune related diseases. Anti-dsDNA-positive reactivity was highly correlated with dDNA and dAT reactivity (r = 0.906, p < 0.0001 and r = 0.93, p < 0.0001, respectively). Although the majority of the 50 selected (37 systemic lupus erythematosus and 13 non-systemic lupus erythematosus) anti-dsDNA-positive sera concomitantly bound to both additional antigens, 7 of these (14%) did not bind to dAT, and 2 (4%) did not bind to dDNA. Anti-dsDNA-positive sera (n = 37) showed a similar pattern, in which 8.1% and 2.7% of sera did not bind to dAT and to dDNA, respectively. In contrast, anti-dsDNA-negative sera from various immune-related diseases bound either ssDNA (12.5%) or dDNA and dAT (12.5%). These data suggest that dsDNA and dAT-based assays detect similar but not identical specificities in the sera of patients suffering from systemic lupus erythematosus and in a proportion of non-systemic lupus erythematosus patients.
authors.affiliation: Clinical Department of Laboratory Diagnosis, University Hospital Center Zagreb, Croatia.
authors.forename: D
authors.initials: D
authors.lastname: Batinić
authors.forename: M
authors.initials: M
authors.lastname: Bozićević
authors.forename: A
authors.initials: A
authors.lastname: Krstulović
authors.forename: D
authors.initials: D
authors.lastname: Bosnić
authors.forename: M
authors.initials: M
authors.lastname: Sentić
authors.forename: J
authors.initials: J
authors.lastname: Markeljević
authors.forename: B
authors.initials: B
authors.lastname: Malenica
authors.forename: N
authors.initials: N
authors.lastname: Cikes
authors.forename: M
authors.initials: M
authors.lastname: Marusić
mesh_terms: D000974:Antibodies, Antinuclear / Q000097:blood*; D003240:Connective Tissue Diseases / Q000097:blood / Q000276:immunology; D004247:DNA / Q000138:chemical synthesis / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007154:Immune System Diseases / Q000097:blood / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D008297:Male; D011067:Poly dA-dT / Q000138:chemical synthesis / Q000276:immunology*
chemical_list: D000974:Antibodies, Antinuclear; D011067:Poly dA-dT; D004247:DNA