title: A novel reactive epitope-based antigen targeted by serum autoantibodies in oligoarticular and polyarticular juvenile idiopathic arthritis and development of an electrochemical biosensor.
abstract: Currently, there are no specific markers for juvenile idiopathic arthritis (JIA) diagnosis, which is based on clinical symptoms and some blood tests for diseases' exclusion. Aiming to select new epitope-based antigens (mimotopes) that could recognize circulating autoantibodies in most JIA forms, we screened a phage displayed random peptide library against IgG antibodies purified from serum of JIA patients. ELISA assay was carried out to confirm immunoreactivity of selected peptides against sera IgG antibodies from JIA patients, healthy children and patients with other autoimmune diseases. The mimotope PRF+1 fused to phage particles was able to efficiently discriminate JIA patients from controls, and for this reason was chosen to be chemically synthesized for validation in a larger sample size. The synthetic peptide was immobilized onto bioelectrodes' surface for antibody detection by electrochemical analyses through differential pulse voltammetry. The PRF+1 synthetic peptide has efficiently discriminated JIA patients from control groups (p<0.0001) with a very good accuracy (AUC>0.84; sensitivity=61%; specificity=91%). The electrochemical platform proved to be fast, low cost and effective in detecting anti-PRF+1 antibodies from JIA patients compared to healthy controls (p=0.0049). Our study describes a novel and promising epitope-based biomarker for JIA diagnosis that can become a useful tool for screening tests, which was successfully incorporated onto an electrochemical biosensor and could be promptly used in field diagnostics.
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil. Electronic address: galber.araujo@gmail.com.
authors.forename: Galber R
authors.initials: GR
authors.lastname: Araujo
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Patricia T
authors.initials: PT
authors.lastname: Fujimura
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Emília R
authors.initials: ER
authors.lastname: Vaz
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Tamiris A
authors.initials: TA
authors.lastname: Silva
authors.affiliation: Laboratório de Biomateriais, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Vinícius R
authors.initials: VR
authors.lastname: Rodovalho
authors.affiliation: Laboratório de Biomateriais, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Ana Graci
authors.initials: AG
authors.lastname: Britto-Madurro
authors.affiliation: Laboratório de Filmes Poliméricos e Nanotecnologia, Instituto de Química, Universidade Federal de Uberlândia, Av. João Naves de Ávila 2121, Uberlândia 38408-100, Minas Gerais, Brazil.
authors.forename: João M
authors.initials: JM
authors.lastname: Madurro
authors.affiliation: Unidade de Investigação em Reumatologia, Instituto de Medicina Molecular, Av. Prof. Egas Moniz, Lisboa 1649-028, Portugal.
authors.forename: João E
authors.initials: JE
authors.lastname: Fonseca
authors.affiliation: Unidade de Reumatologia Pediátrica, Hospital de Clínicas, Faculdade de Medicina da Universidade Federal de Uberlândia, Av. Pará 1720, Bloco 2U, Uberlândia 38400-902, Brazil.
authors.forename: Carlos H M
authors.initials: CH
authors.lastname: Silva
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Paula S
authors.initials: PS
authors.lastname: Santos
authors.affiliation: Unidade de Investigação em Reumatologia, Instituto de Medicina Molecular, Av. Prof. Egas Moniz, Lisboa 1649-028, Portugal.
authors.forename: Ana F
authors.initials: AF
authors.lastname: Mourão
authors.affiliation: Unidade de Investigação em Reumatologia, Instituto de Medicina Molecular, Av. Prof. Egas Moniz, Lisboa 1649-028, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Canhão
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil; Department of Medical Microbiology and Immunology, University of California Davis, 1 Shields Avenue, Tupper Hall, Rm. 3146, Davis, CA 95616, USA.
authors.forename: Luiz R
authors.initials: LR
authors.lastname: Goulart
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, Lisboa 1649-028, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Gonçalves
authors.affiliation: Laboratório de Nanobiotecnologia, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Av. Amazonas, Bloco 2E, sala 248, Uberlândia 38400-902, Minas Gerais, Brazil.
authors.forename: Carlos
authors.initials: C
authors.lastname: Ueira-Vieira
mesh_terms: D000293:Adolescent; D000595:Amino Acid Sequence; D001171:Arthritis, Juvenile / Q000175:diagnosis / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001324:Autoantigens / Q000737:chemistry / Q000276:immunology*; D015415:Biomarkers; D015374:Biosensing Techniques; D061505:Cell Surface Display Techniques; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry / Q000276:immunology; D012372:ROC Curve; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D015415:Biomarkers; D000939:Epitopes; D019151:Peptide Library; D010455:Peptides
keywords: Autoantigens; Electrochemical biosensor; Juvenile idiopathic arthritis; Phage display