title: Standardization of an ELISA test using a recombinant nucleoprotein from the Junin virus as the antigen and serological screening for arenavirus among the population of Nova Xavantina, State of Mato Grosso.
abstract: BACKGROUND
  Arenavirus hemorrhagic fever is a severe emerging disease.
  
  
  METHODS
  Considering that the levels of antibodies against arenavirus in the Brazilian population are completely unknown, we have standardized an ELISA test for detecting IgG antibodies using a recombinant nucleoprotein from the Junin virus as the antigen. This protein was obtained by inserting the gene of the Junin virus nucleoprotein into the genome of Autographa californica nucleopolyhedrovirus, using the Bac-to-Bac baculovirus expression system. This recombinant baculovirus was used to infect S. frugiperda cells (SF9).
  
  
  RESULTS
  The infection resulted in synthesis of high concentrations of recombinant protein. This protein was detected on 12.5% polyacrylamide gel and by means of Western blot. Using the standardized ELISA test, 343 samples from the population of Nova Xavantina were analyzed. We observed that 1.4% of the serum samples (five samples) presented antibody titers against arenavirus.
  
  
  CONCLUSIONS
  These results show the population studied may present exposure to arenavirus infection.
authors.affiliation: Virology Research Center, School of Medicine, University of São Paulo in Ribeirão Preto, SP, Brazil. alexmmachado@usp.br
authors.forename: Alex Martins
authors.initials: AM
authors.lastname: Machado
authors.forename: Glauciane Garcia
authors.initials: GG
authors.lastname: Figueiredo
authors.forename: Gelse Maria
authors.initials: GM
authors.lastname: Campos
authors.forename: Mario Enrique
authors.initials: ME
authors.lastname: Lozano
authors.forename: Aline Rafaela da Silva Rodrigues
authors.initials: AR
authors.lastname: Machado
authors.forename: Luiz Tadeu Moraes
authors.initials: LT
authors.lastname: Figueiredo
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000276:immunology*; D001117:Arenaviridae Infections / Q000175:diagnosis*; D018050:Arenavirus / Q000235:genetics / Q000276:immunology*; D001938:Brazil; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D018051:Junin virus / Q000235:genetics / Q000276:immunology*; D008297:Male; D009698:Nucleoproteins / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D007074:Immunoglobulin G; D009698:Nucleoproteins; D011994:Recombinant Proteins