title: Development of two Trichoplusia ni larvae-derived ELISAs for the detection of antibodies against replicase and capsid proteins of porcine circovirus type 2 in domestic pigs.
abstract: The main aim of the present study was to describe new methods for the identification of antibodies against the PCV2 capsid (Cap) and replicase (Rep) proteins in pig sera. Specifically, two new indirect enzyme-linked immunosorbent assays (ELISA) were developed based on recombinant PCV2 Cap (rCap) and Rep/Rep' (rRep) proteins expressed in baculovirus and produced in Trichoplusia ni insect larvae. Both assays were validated by testing serum samples in a longitudinal study of 107 animals with different clinico-pathological features of PCV2 infection: pigs with postweaning multisystemic wasting syndrome (PMWS), wasted pigs without a diagnosis of PMWS and healthy animals. Longitudinal antibody profiles indicated that healthy animals had significantly higher anti-Cap and anti-Rep antibody levels than the rest of the animal groups at 11 weeks of age. Moreover, PMWS affected pigs could be distinguished from the rest of the pig groups by their lower anti-Rep antibody levels at 11 weeks of age and at necropsy. The results demonstrate the potential of these two ELISAs for large-scale serological studies. This study represents the first longitudinal study of the induction of anti-Cap and anti-Rep antibodies in farms affected by PMWS, from 1 week of age until the occurrence of disease.
authors.affiliation: Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain. eva.perez@cresa.uab.cat
authors.forename: Eva
authors.initials: E
authors.lastname: Pérez-Martín
authors.forename: Llorenç
authors.initials: L
authors.lastname: Grau-Roma
authors.forename: Jordi M
authors.initials: JM
authors.lastname: Argilaguet
authors.forename: Miquel
authors.initials: M
authors.lastname: Nofrarías
authors.forename: José M
authors.initials: JM
authors.lastname: Escribano
authors.forename: Silvia
authors.initials: S
authors.lastname: Gómez-Sebastián
authors.forename: Joaquim
authors.initials: J
authors.lastname: Segalés
authors.forename: Fernando
authors.initials: F
authors.lastname: Rodríguez
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000235:genetics; D016367:Baculoviridae / Q000235:genetics; D036022:Capsid Proteins / Q000235:genetics; D018173:Circoviridae Infections / Q000175:diagnosis / Q000662:veterinary*; D017925:Circovirus / Q000276:immunology / Q000302:isolation & purification*; D004259:DNA-Directed DNA Polymerase / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D007814:Larva / Q000821:virology; D007915:Lepidoptera / Q000821:virology; D034421:Sus scrofa
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; C023140:DNA replicase; D004259:DNA-Directed DNA Polymerase