title: A peptide DNA surrogate that binds and inhibits anti-dsDNA antibodies.
abstract: Autoantibodies to dsDNA are an important diagnostic marker and pathogenic factor for systemic lupus erythematosus (SLE). Although the anti-dsDNA antibodies present in SLE are indicative of an antigen-driven response, the antigen has not been conclusively identified. The specific SLE anti-dsDNA antibodies were obtained by affinity purification using a dsDNA-coupled Sepharose column. Using the anti-dsDNA antibodies to screen a phage peptide display library, we demonstrated that purified polyclonal anti-dsDNA antibodies and a monoclonal anti-dsDNA antibody specifically bind a 15 mer peptide ASPVTARVLWKASHV. This chemically synthesized peptide could be recognized by anti-dsDNA antibodies in ELISA and Dot blot. This 15 mer peptide can inhibit anti-dsDNA antibodies binding to dsDNA antigen in immunoassays and in the Crithidia luciliae assay while a control peptide did not inhibit anti-dsDNA antibodies. This study demonstrates the potential usefulness of the peptide DNA surrogate in diagnostic tests of SLE and in the investigation of the origin of anti-dsDNA antibodies. It may also be used in studies of the DNA-anti-DNA antibody interaction.
authors.affiliation: Arthritis and Immunology Program, Oklahoma Medical Research Foundation, 825 Northeast 13th Street, Oklahoma City, OK 73104, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Morris
authors.initials: M
authors.lastname: Reichlin
mesh_terms: D000974:Antibodies, Antinuclear / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000378:metabolism*; D007155:Immunologic Factors / Q000378:metabolism; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D019151:Peptide Library; D020135:Peptide Nucleic Acids / Q000378:metabolism*; D010455:Peptides / Q000138:chemical synthesis* / Q000276:immunology* / Q000378:metabolism
chemical_list: D000974:Antibodies, Antinuclear; D007074:Immunoglobulin G; D007155:Immunologic Factors; D019151:Peptide Library; D020135:Peptide Nucleic Acids; D010455:Peptides