title: Vaccine potential of a nonflagellated, virulence-plasmid-cured (fliD-, pSEVΔ) mutant of Salmonella Enteritidis for chickens.
abstract: The aim of these studies was to assess residual virulence and early protective capacity of a negatively markered live attenuated vaccine candidate Salmonella Enteritidis mutant against a highly virulent S. Enteritidis strain using a dayold chicken model. Nonflagellated FliD negative mutants of Salmonella Enteritidis 11 (SE11) with and without the virulence plasmid proved to be sufficiently attenuated (limited invasiveness in vitro/in vivo) without reduced ability to colonise chicken gut. The early protective activity of a nonflagellated, virulence-plasmidcured (fliD-, pSEVΔ) mutant against organ invasion, caecal colonisation and faecal shedding by the highly virulent challenge strain S. Enteritidis 147 Nal(R) proved to be effective and safe. The innate and adaptive immunity was demonstrable during the first four weeks of life, and the serological response was clearly distinguishable from the response induced by the wild parental strain. In conclusion, we provided data for the first time about a virulence-plasmid-cured, nonflagellated mutant of S. Enteritidis to serve as a basis for development of a negatively markered potential live oral vaccine against virulent S. Enteritidis in chicken.
authors.affiliation: Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences , Budapest , Hungary.|Ceva-Phylaxia BIO R&D Bacteriological Integrated Development Unit , Szállás u. 5, H-1107 Budapest , Hungary.
authors.forename: Ariel
authors.initials: A
authors.lastname: Imre
authors.affiliation: Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences , Budapest , Hungary.
authors.forename: Ama
authors.initials: A
authors.lastname: Szmolka
authors.affiliation: NARIC Agricultural Biotechnology Institute , Gödöllő , Hungary.
authors.forename: Ferenc
authors.initials: F
authors.lastname: Olasz
authors.affiliation: Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences , Budapest , Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Nagy
keywords: Salmonella Enteritidis; chicken; fliD flagellin; vaccine; virulence plasmid