title: An African horse sickness virus serotype 4 recombinant canarypox virus vaccine elicits specific cell-mediated immune responses in horses.
abstract: A recombinant canarypox virus vectored vaccine co-expressing synthetic genes encoding outer capsid proteins, VP2 and VP5, of African horse sickness virus (AHSV) serotype 4 (ALVAC(®)-AHSV4) has been demonstrated to fully protect horses against homologous challenge with virulent field virus. Guthrie et al. (2009) detected weak and variable titres of neutralizing antibody (ranging from <10 to 40) 8 weeks after vaccination leading us to hypothesize that there could be a participation of cell mediated immunity (CMI) in protection against AHSV4. The present study aimed at characterizing the CMI induced by the experimental ALVAC(®)-AHSV4 vaccine. Six horses received two vaccinations twenty-eight days apart and three horses remained unvaccinated. The detection of VP2/VP5 specific IFN-γ responses was assessed by enzyme linked immune spot (ELISpot) assay and clearly demonstrated that all ALVAC(®)-AHSV4 vaccinated horses developed significant IFN-γ production compared to unvaccinated horses. More detailed immune responses obtained by flow cytometry demonstrated that ALVAC(®)-AHSV4 vaccinations induced immune cells, mainly CD8(+) T cells, able to recognize multiple T-epitopes through all VP2 and only the N-terminus sequence of VP5. Neither VP2 nor VP5 specific IFN-γ responses were detected in unvaccinated horses. Overall, our data demonstrated that an experimental recombinant canarypox based vaccine induced significant CMI specific for both VP2 and VP5 proteins of AHSV4.
authors: Merial S.A.S., R&D, Lyon, France. hanane.elgarch@merial.com
authors: H
authors: H
authors: El Garch
authors: J E
authors: JE
authors: Crafford
authors: P
authors: P
authors: Amouyal
authors: P Y
authors: PY
authors: Durand
authors: C
authors: C
authors: Edlund Toulemonde
authors: L
authors: L
authors: Lemaitre
authors: V
authors: V
authors: Cozette
authors: A
authors: A
authors: Guthrie
authors: J M
authors: JM
authors: Minke
mesh_terms: D000355:African Horse Sickness / Q000276:immunology* / Q000517:prevention & control*; D000356:African Horse Sickness Virus / Q000235:genetics / Q000276:immunology*; D000818:Animals; D028121:Canarypox virus / Q000235:genetics*; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D006736:Horses; D007111:Immunity, Cellular / Q000276:immunology; D007114:Immunization / Q000662:veterinary; D007371:Interferon-gamma / Q000097:blood; D008297:Male; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology
chemical_list: D036022:Capsid Proteins; D014614:Vaccines, Synthetic; D014765:Viral Vaccines; D007371:Interferon-gamma