title: Flow-Induced Dispersion Analysis for Probing Anti-dsDNA Antibody Binding Heterogeneity in Systemic Lupus Erythematosus Patients: Toward a New Approach for Diagnosis and Patient Stratification.
abstract: Detection of immune responses is important in the diagnosis of many diseases. For example, the detection of circulating autoantibodies against double-stranded DNA (dsDNA) is used in the diagnosis of Systemic Lupus Erythematosus (SLE). It is, however, difficult to reach satisfactory sensitivity, specificity, and accuracy with established assays. Also, existing methodologies for quantification of autoantibodies are challenging to transfer to a point-of-care setting. Here we present the use of flow-induced dispersion analysis (FIDA) for rapid (minutes) measurement of autoantibodies against dsDNA. The assay is based on Taylor dispersion analysis (TDA) and is fully automated with the use of standard capillary electrophoresis (CE) based equipment employing fluorescence detection. It is robust toward matrix effects as demonstrated by the direct analysis of samples composed of up to 85% plasma derived from human blood samples, and it allows for flexible exchange of the DNA sequences used to probe for the autoantibodies. Plasma samples from SLE positive patients were analyzed using the new FIDA methodology as well as by standard indirect immunofluorescence and solid-phase immunoassays. Interestingly, the patient antibodies bound DNA sequences with different affinities, suggesting pronounced heterogeneity among autoantibodies produced in SLE. The FIDA based methodology is a new approach for autoantibody detection and holds promise for being used for patient stratification and monitoring of disease activity.
authors: Department of Pharmacy, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark.
authors: Nicklas N
authors: NN
authors: Poulsen
authors: Department of Pharmacy, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark.
authors: Morten E
authors: ME
authors: Pedersen
authors: Department of Pharmacy, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark.
authors: Jesper
authors: J
authors: Østergaard
authors: Department of Pharmacy, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark.
authors: Nickolaj J
authors: NJ
authors: Petersen
authors: Department of Autoimmunology & Biomarkers, Statens Serum Institut , Artillerivej 5, 2300 Copenhagen, Denmark.
authors: Christoffer T
authors: CT
authors: Nielsen
authors: Department of Autoimmunology & Biomarkers, Statens Serum Institut , Artillerivej 5, 2300 Copenhagen, Denmark.|Department of Clinicial Biochemistry, Odense University Hospital, University of Southern Denmark , Sdr. Boulevard 29, 5000 Odense, Denmark.
authors: Niels H H
authors: NH
authors: Heegaard
authors: Department of Pharmacy, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark.
authors: Henrik
authors: H
authors: Jensen
mesh_terms: D000974:Antibodies, Antinuclear / Q000097:blood / Q000276:immunology*; D004247:DNA / Q000276:immunology*; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004797:Enzyme-Linked Immunosorbent Assay; D004867:Equipment Design; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D017060:Patient Satisfaction
chemical_list: D000974:Antibodies, Antinuclear; D004247:DNA