Evidence of autoantibodies to cell membrane associated DNA (cultured lymphocytes): a new specific marker for rapid identification of systemic lupus erythematosus

• Published in: Annals of the rheumatic diseases 1998-10, Vol.57 (10), p.606-613
• Main Authors: Servais, Geneviève, Guillaume, Marie-Paule, Dumarey, Nicolas, Duchateau, Jean
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; anti-nuclear antibodies; Antibodies, Antinuclear - blood; Antibody Specificity; Arthritis - diagnosis; Autoimmune diseases; Biological and medical sciences; Biomarkers - blood; Cell Membrane - immunology; cytoplasmic membrane associated DNA; Deoxyribonucleic acid; Diagnosis, Differential; Disease; DNA; DNA - immunology; DNA, Single-Stranded - immunology; Experiments; Extended Reports; Female; Fluorescent Antibody Technique, Indirect; Humans; immunofluorescence; Immunoglobulin G - blood; Immunoglobulins; Lupus; Lupus Erythematosus, Systemic - diagnosis; Lupus Erythematosus, Systemic - immunology; Lymphocytes; Lymphoma; Male; Medical sciences; Methanol; Middle Aged; Patients; Proteins; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; systemic lupus erythematosus; Tissue Fixation; Tumor Cells, Cultured
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.57.10.606

OBJECTIVE Autoantibodies to cell membrane associated DNA are described in systemic lupus erythematosus (SLE). The specificity of these antibodies differ from antibodies to nuclear DNA. METHODS Using indirect immunofluorescence, a specific IgG was detected giving a characteristic pattern of continuous peripheral membrane fluorescence on cultured B-lymphocytes. RESULTS This pattern was observed in 53 of 80 serum samples of SLE patients but absent in the serum samples of the control populations: 15 rheumatoid arthritis, 38 ankylosing spondylarthritis, 17 non-inflammatory osteopenic patients, and 224 blood donors. In 34 Sjögren syndrome’s patients one only showed a positive test. The cmDNA specificity of these antibodies was confirmed by pattern extinction with DNAse but not RNase or protease pre-treatment of the cells. IgG to cmDNA, separated by absorption/elution from purified cmDNA immobilised on DEAE-nitrocellulose reproduced the immunofluorescence pattern pictures. Extensive serum depletion of anti-double strand or single strand DNA antibodies by absorption to cellulose bound ds- or ss-DNA affected marginally the pericellular fluorescence revealing some minor cross reactivity with nuclear DNA. Moreover, in SLE patients without detectable antibody to ds-DNA, pericellular fluorescence could be visible. CONCLUSION This novel rapid immunofluorescence method may serve as an identification test of SLE patients. Given its positive (97.1%) and negative (92.9%) predictive value, sensitivity (66%) and specificity (99.5%), it improves on other diagnostic tests such as the detection of antibodies to Sm.