title: Evaluation of the immune response elicited by vaccination with viral vectors encoding FMDV capsid proteins and boosted with inactivated virus.
abstract: The aim of the present study was to assess the effect of introducing a priming step with replication-defective viral vectors encoding the capsid proteins of FMDV, followed by a boost with killed virus vaccines, using a suitable BALB/c mice model. Additionally, the immune response to other combined vector immunization regimens was studied. For this purpose, we analyzed different prime-boost immunizations with recombinant adenovirus (Ad), herpesvirus amplicons (Hs) and/or killed virus (KV) vaccines. The highest antibody titers were found in the group that received two doses of adjuvanted KV (P<0.002). Antibody titers were higher in those groups receiving a mixed regimen of vectors, compared to immunization with either vector alone (P<0.0001). Priming with any of the viral vectors induced a shift of the cytokine balance toward a Th1 type immune response regardless of the delivery system used for boosting. The highest IgG1 titer was induced by two doses of adjuvanted KV (P=0.0002) and the highest IgG2a titer corresponded to the group primed with Ad and boosted with KV (P=0.01). Re-stimulation of all groups of mice with 0.5 μg of inactivated virus five months later resulted in a fast increase of antibody titers in all the groups tested. After virus stimulation, antibody titers in the groups that received KV alone or Ad prime-KV boost, were indistinguishable (P=0.800). Protection from challenge was similar (75%) in the groups of animals that received Ad prime-Hs boost or Ad prime-KV boost, or two doses of oil-adjuvanted KV. The data presented in this study suggest that sequential immunization with viral vectors-based vaccines combined with protein-based vaccines have the potential to enhance the quality of the immune response against FMDV.
authors.affiliation: Centro de Virología Animal, Instituto de Ciencia y Tecnología Dr. Cesar Milstein, CONICET, Saladillo 2468, C1440FFX Ciudad de Buenos Aires, Argentina.
authors.forename: Carina
authors.initials: C
authors.lastname: Romanutti
authors.forename: Alejandra
authors.initials: A
authors.lastname: D'Antuono
authors.forename: Carlos
authors.initials: C
authors.lastname: Palacios
authors.forename: Valeria
authors.initials: V
authors.lastname: Quattrocchi
authors.forename: Patricia
authors.initials: P
authors.lastname: Zamorano
authors.forename: Jose
authors.initials: J
authors.lastname: La Torre
authors.forename: Nora
authors.initials: N
authors.lastname: Mattion
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000276:immunology*; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology*; D004195:Disease Models, Animal; D005536:Foot-and-Mouth Disease / Q000276:immunology* / Q000517:prevention & control; D029544:Foot-and-Mouth Disease Virus / Q000235:genetics / Q000276:immunology*; D005822:Genetic Vectors / Q000235:genetics; D057809:HEK293 Cells; D006564:Herpesviridae / Q000235:genetics / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D014611:Vaccination / Q000662:veterinary*; D015164:Vaccines, Inactivated / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*; D038301:Virus Inactivation; D014779:Virus Replication / Q000235:genetics
chemical_list: D000914:Antibodies, Viral; D036022:Capsid Proteins; D007074:Immunoglobulin G; D015164:Vaccines, Inactivated; D014765:Viral Vaccines