title: Systemic DNA immunization against ovine lentivirus using particle-mediated epidermal delivery and modified vaccinia Ankara encoding the gag and/or env genes.
abstract: To determine whether systemic immunization with plasmid DNA and virus vector against visna/maedi virus (VMV) would induce protective immune responses, sheep were immunized with VMV gag and/or env sequences using particle-mediated epidermal bombardment and injection of recombinant modified vaccinia Ankara. The results showed that immunization induced both humoral and cell-mediated responses prior to and after virus challenge. The vaccination protocol did not prevent infection, but immunization with the gag gene or a combination of gag and env genes resulted in significantly reduced provirus loads in blood and mediastinal lymph node, respectively. Provirus loads in lung and draining lymph node were unaffected, but p25 expression was undetectable in lungs of animals immunized with a combination of gag and env genes. Analysis of target tissues for lesions at post-mortem showed that immunization with the env gene caused a significant increase in lesion score, while the gag gene or a combination of gag and env genes had no effect. Inclusion of the ovine interferon-gamma gene in the initial priming mixture had minimal effect on immune responses, provirus load, or lesion development, although it resulted in a decreased p25 expression in the lung. The results thus show that systemic immunization with gag or a combination of gag and env genes reduces provirus load in blood and lymphoid tissue, respectively whereas env immunization has no effect on provirus load but increased lesion development.
authors.affiliation: University of Edinburgh, Edinburgh, UK.
authors.forename: H
authors.initials: H
authors.lastname: Niesalla
authors.forename: X
authors.initials: X
authors.lastname: de Andrés
authors.forename: C
authors.initials: C
authors.lastname: Barbezange
authors.forename: C
authors.initials: C
authors.lastname: Fraisier
authors.forename: R
authors.initials: R
authors.lastname: Reina
authors.forename: H
authors.initials: H
authors.lastname: Arnarson
authors.forename: E
authors.initials: E
authors.lastname: Biescas
authors.forename: M
authors.initials: M
authors.lastname: Mazzei
authors.forename: T N
authors.initials: TN
authors.lastname: McNeilly
authors.forename: C
authors.initials: C
authors.lastname: Liu
authors.forename: C
authors.initials: C
authors.lastname: Watkins
authors.forename: M
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authors.lastname: Perez
authors.forename: M L
authors.initials: ML
authors.lastname: Carrozza
authors.forename: P
authors.initials: P
authors.lastname: Bandecchi
authors.forename: C
authors.initials: C
authors.lastname: Solano
authors.forename: H
authors.initials: H
authors.lastname: Crespo
authors.forename: I
authors.initials: I
authors.lastname: Glaria
authors.forename: C
authors.initials: C
authors.lastname: Huard
authors.forename: D J
authors.initials: DJ
authors.lastname: Shaw
authors.forename: I
authors.initials: I
authors.lastname: de Blas
authors.forename: D
authors.initials: D
authors.lastname: de Andrés
authors.forename: F
authors.initials: F
authors.lastname: Tolari
authors.forename: S
authors.initials: S
authors.lastname: Rosati
authors.forename: M
authors.initials: M
authors.lastname: Suzan-Monti
authors.forename: V
authors.initials: V
authors.lastname: Andrésdottir
authors.forename: S
authors.initials: S
authors.lastname: Torsteinsdottir
authors.forename: G
authors.initials: G
authors.lastname: Petursson
authors.forename: J
authors.initials: J
authors.lastname: Badiola
authors.forename: L
authors.initials: L
authors.lastname: Lujan
authors.forename: M
authors.initials: M
authors.lastname: Pepin
authors.forename: B
authors.initials: B
authors.lastname: Amorena
authors.forename: B
authors.initials: B
authors.lastname: Blacklaws
authors.forename: G D
authors.initials: GD
authors.lastname: Harkiss
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D019470:Biolistics; D004817:Epidermis / Q000821:virology; D005260:Female; D015752:Genes, env / Q000235:genetics* / Q000276:immunology; D015750:Genes, gag / Q000235:genetics* / Q000276:immunology; D007114:Immunization; D008297:Male; D011021:Pneumonia, Progressive Interstitial, of Sheep / Q000517:prevention & control* / Q000821:virology; D011533:Proviruses / Q000302:isolation & purification; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014616:Vaccinia virus / Q000235:genetics* / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014771:Virion / Q000235:genetics / Q000276:immunology; D014790:Visna-maedi virus
chemical_list: D000914:Antibodies, Viral; D019444:Vaccines, DNA; D014765:Viral Vaccines