title: Porcine reproductive and respiratory syndrome virus (PRRSV)-specific mAbs: supporting diagnostics and providing new insights into the antigenic properties of the virus.
abstract: The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important viral pathogens in the swine industry. Despite great efforts of pig holders, veterinarians, researchers and vaccine developers, the virus still causes major production losses. It is clear that efficient and correct monitoring and rational development of vaccines are crucial in the combat against this pathogen. PRRSV-specific monoclonal antibodies (mAbs) are essential tools for both diagnostic and research purposes. This study describes the production of PRRSV GP3-, GP5- and N-specific hybridomas and an extensive characterization of the mAbs. The N-specific mAbs generated in this study appear to be useful tools for diagnostics, as they were found to react with genetically very different PRRSV isolates and may serve to discriminate between European and American type PRRSV isolates. These mAbs also allowed detection of the PRRSV N protein in both formalin-fixed, paraffin-embedded tissue sections and frozen tissue sections of PRRSV-infected lungs, further illustrating their diagnostic value. Different neutralization assays pointed out that none of the GP3- and GP5-specific mAbs tested shows virus-neutralizing capacity. This is noteworthy, as these mAbs recognize epitopes in the predicted ectodomains of their target protein and since the GP5-specific antibodies specifically react with the antigenic region that corresponds to the "major neutralizing epitope" suggested for American type PRRSV. The current findings argue against an important role of the identified antigenic regions in direct antibody-mediated neutralization of European type PRRSV in vivo. However, it is also clear that findings concerning a specific PRRSV epitope cannot always be generalized, as the antigenic determinants and their biological properties may differ radically between different virus isolates.
authors.affiliation: Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium. wander.vanbreedam@UGent.be
authors.forename: Wander
authors.initials: W
authors.lastname: Van Breedam
authors.forename: Sarah
authors.initials: S
authors.lastname: Costers
authors.forename: Merijn
authors.initials: M
authors.lastname: Vanhee
authors.forename: Carl A
authors.initials: CA
authors.lastname: Gagnon
authors.forename: Irene M
authors.initials: IM
authors.lastname: Rodríguez-Gómez
authors.forename: Marc
authors.initials: M
authors.lastname: Geldhof
authors.forename: Mieke
authors.initials: M
authors.lastname: Verbeeck
authors.forename: Jan
authors.initials: J
authors.lastname: Van Doorsselaere
authors.forename: Uladzimir
authors.initials: U
authors.lastname: Karniychuk
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Nauwynck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000956:Antigens, Viral / Q000276:immunology*; D002460:Cell Line; D000939:Epitopes; D015967:Gene Expression Regulation, Viral; D006825:Hybridomas; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D019318:Porcine Reproductive and Respiratory Syndrome / Q000175:diagnosis*; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology*; D013552:Swine; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
chemical_list: D000911:Antibodies, Monoclonal; D000956:Antigens, Viral; D000939:Epitopes; D014764:Viral Proteins