title: A recombinant multiepitope protein for hepatitis B diagnosis.
abstract: Hepatitis B is a liver inflammation caused by hepatitis B virus (HBV) and can be diagnosed in clinical stage by hepatitis B core antibody from IgM class (anti-HBcIgM). Hepatitis B core antibody from IgG class (Anti-HBcIgG) appears quickly after IgM, reaching high titers in chronic hepatitis, and remains even after cure. Since hepatitis B core antibody (anti-HBc) is the first antibody identified and sometimes the only marker detected during the course of infection, it can be used both to indicate HBV acute infection (anti-HBc-IgM) and to identify individuals who have come into contact with the virus (anti-HBc-IgG). In this work we propose a recombinant hepatitis B core multiepitope antigen (rMEHB) to be used for diagnosis of hepatitis B. For this purpose, a synthetic gene coding for rMEHB was designed and cloned into vector pET21a with a 6xHis tag at the C-terminal. Time course induction in E. coli showed an induced protein with an apparent molecular mass of ~21 kDa. Protein purification was performed by a single step with affinity chromatography Ni-NTA. Circular dichroism spectroscopy indicated rMEHB as a thermal stable protein at pH 7.0 and 8.0. In these conditions rMEHB was successfully used to perform an enzyme linked immuno sorbent assay (ELISA) with positive and negative sera.
authors.affiliation: Laboratório de Biologia Molecular, Universidade de Brasília, 70910-900 Brasília, DF, Brazil.
authors.forename: Marilen Queiroz
authors.initials: MQ
authors.lastname: de Souza
authors.forename: Alexsandro Sobreira
authors.initials: AS
authors.lastname: Galdino
authors.forename: José Carlos
authors.initials: JC
authors.lastname: dos Santos
authors.forename: Marcus Vinicius
authors.initials: MV
authors.lastname: Soares
authors.forename: Yanna C
authors.initials: YC
authors.lastname: de Nóbrega
authors.forename: Alice da Cunha Morales
authors.initials: Ada C
authors.lastname: Alvares
authors.forename: Sonia Maria
authors.initials: SM
authors.lastname: de Freitas
authors.forename: Fernando Araripe Gonçalves
authors.initials: FA
authors.lastname: Torres
authors.forename: Maria Sueli Soares
authors.initials: MS
authors.lastname: Felipe
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry / Q000302:isolation & purification; D006509:Hepatitis B / Q000175:diagnosis* / Q000276:immunology; D006512:Hepatitis B Core Antigens / Q000737:chemistry / Q000276:immunology; D006358:Hot Temperature; D006801:Humans; D007118:Immunoassay; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D058767:Protein Unfolding; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification; D013997:Time Factors
chemical_list: D000939:Epitopes; D006512:Hepatitis B Core Antigens; D011994:Recombinant Proteins