title: Induction of protective immune response in cats by vaccination with feline leukemia virus iscom.
abstract: An effective candidate subunit vaccine consisting of the gp 70/85 of feline leukemia virus (FeLV) was prepared by using the immunostimulating complex (iscom) method for the presentation of membrane proteins of enveloped viruses. Two 32-wk-old specific pathogen-free (SPF) cats were immunized with a FeLV iscom vaccine prepared from the supernatant fluid of the FL74 tumor cell line without adjuvant. Both cats developed FeLV serum antibodies, as measured in an enzyme-linked immunosorbent assay (ELISA) and in a virus neutralization test. A proportion of the antibodies were directed to an epitope located on gp70/85, which was shown in competition ELISA with a peroxidase-labeled virus-neutralizing monoclonal antibody to be shared by all three subtypes of FeLV. The protective effect of FeLV iscom was studied by vaccinating six 8-wk-old SPF cats with iscom prepared from cell culture supernatant of another tumor cell line F422, followed by oronasal challenge with 10(6) ffu FeLV-A (strain Glasgow-1). Six unvaccinated cats were also challenged with the same dose of FeLV. The vaccinated cats developed FeLV serum antibodies, some of which were directed to the shared epitope on gp70/85. At 10 wk after challenge, none was viremic, whereas three of the control cats had developed FeLV viremia. The potential of FeLV iscom as a vaccine against FeLV-associated disease in cats, and of iscom vaccines for protection against mammalian retrovirus infections, is discussed.
authors.forename: A
authors.initials: A
authors.lastname: Osterhaus
authors.forename: K
authors.initials: K
authors.lastname: Weijer
authors.forename: F
authors.initials: F
authors.lastname: Uytdehaag
authors.forename: O
authors.initials: O
authors.lastname: Jarrett
authors.forename: B
authors.initials: B
authors.lastname: Sundquist
authors.forename: B
authors.initials: B
authors.lastname: Morein
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000032:analysis / Q000276:immunology; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis*; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D002415:Cats; D003101:Collodion; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005256:Leukemia Virus, Feline / Q000276:immunology*; D007942:Leukemia, Experimental / Q000276:immunology; D008297:Male; D008565:Membrane Proteins / Q000008:administration & dosage / Q000032:analysis / Q000276:immunology; D009500:Neutralization Tests; D010209:Paper; D015682:Retroviridae Proteins, Oncogenic; D014759:Viral Envelope Proteins / Q000008:administration & dosage* / Q000032:analysis / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000032:analysis / Q000276:immunology; D014766:Viremia / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D008565:Membrane Proteins; D015682:Retroviridae Proteins, Oncogenic; D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C045569:feline leukemia virus vaccine; D003101:Collodion