title: Discovery of biomarkers for systemic lupus erythematosus using a library of synthetic autoantigen surrogates.
abstract: Antibodies to a wide range of self-antigens, including those directed against nucleic acids or nucleic acid-binding proteins are the essential biomarkers for diseases such as systemic lupus erythematosus (SLE). Highly complex libraries of nonamers consisting of N-substituted glycines (peptoids) were screened for compounds that bound IgG from patients with SLE and earlier, incomplete autoimmune syndromes. Peptoids were identified that could identify subjects with SLE and related syndromes with a high sensitivity (70%) and specificity (97.5%). Immobilized peptoids were used to isolate IgG from both healthy subjects and SLE patients that reacted with known RNA-binding proteins. In the case of SLE patients, the peptoid-purified IgG reacted with several autoantigens, suggesting that the peptoids are capable of interacting with multiple, structurally similar molecules. These results show that the measurement of IgG binding to peptoids can identify subjects with high levels of pathogenic autoantibodies.
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Jiexia
authors.initials: J
authors.lastname: Quan
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Akshai
authors.initials: A
authors.lastname: Lakhanpal
authors.affiliation: The Department of Chemistry, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA; Opko Health, Inc., 555 Heritage Dr., Jupiter, FL 33458, USA.
authors.forename: M Muralidhar
authors.initials: MM
authors.lastname: Reddy
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Sayed
authors.initials: S
authors.lastname: Zaman
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Quan-Zhen
authors.initials: QZ
authors.lastname: Li
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Dwight C
authors.initials: DC
authors.lastname: German
authors.affiliation: The Department of Medicine, Penn State M.S. Hershey Medical Center, Hershey, PA 17033, USA.
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Olsen
authors.affiliation: The Department of Chemistry, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kodadek
authors.affiliation: Department of Medicine, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Immunology, UT Southwestern Medical Center, Dallas, TX 75390, USA; The Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA. Electronic address: David.Karp@UTSouthwestern.edu.
authors.forename: David R
authors.initials: DR
authors.lastname: Karp
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000097:blood / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology*; D019151:Peptide Library; D034444:Peptoids / Q000276:immunology; D015203:Reproducibility of Results
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D015415:Biomarkers; D007074:Immunoglobulin G; D019151:Peptide Library; D034444:Peptoids
keywords: Autoantibodies; Peptoids; Systemic lupus erythematosus