title: Reassessment of feline leukaemia virus (FeLV) vaccines with novel sensitive molecular assays.
abstract: We previously described antigen negative, provirus positive cats. Subsequently, we hypothesized that efficacious FeLV vaccines cannot prevent minimal viral replication. Thus, we vaccinated cats with either a canarypox-vectored live or a killed virus vaccine and analyzed the challenge outcome with quantitative PCR and a newly established real-time RT-PCR. When judged by conventional parameters (antigenaemia, virus isolation), most of the vaccinated cats were, as expected, protected from persistent viraemia. However, all cats were found to be plasma viral RNA positive. The loads were significantly associated with the infection outcome. Thus, commonly used FeLV vaccines understood to be successful model antiretroviral vaccines protecting against FeLV-related diseases do not confer sterilizing immunity.
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 260, CH-8057 Zurich, Switzerland. rhofmann@vetclinics.unizh.ch
authors.forename: Regina
authors.initials: R
authors.lastname: Hofmann-Lehmann
authors.forename: Ravi
authors.initials: R
authors.lastname: Tandon
authors.forename: Felicitas S
authors.initials: FS
authors.lastname: Boretti
authors.forename: Marina L
authors.initials: ML
authors.lastname: Meli
authors.forename: Barbara
authors.initials: B
authors.lastname: Willi
authors.forename: Valentino
authors.initials: V
authors.lastname: Cattori
authors.forename: Maria A
authors.initials: MA
authors.lastname: Gomes-Keller
authors.forename: Pete
authors.initials: P
authors.lastname: Ossent
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Golder
authors.forename: J Norman
authors.initials: JN
authors.lastname: Flynn
authors.forename: Hans
authors.initials: H
authors.lastname: Lutz
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002415:Cats; D004797:Enzyme-Linked Immunosorbent Assay; D005256:Leukemia Virus, Feline / Q000276:immunology*; D012367:RNA, Viral / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014611:Vaccination; D019562:Viral Load; D014765:Viral Vaccines / Q000276:immunology*; D014766:Viremia / Q000517:prevention & control
chemical_list: D000914:Antibodies, Viral; D012367:RNA, Viral; D014765:Viral Vaccines