|HU, HAIXIA - Southwest University|
Submitted to: International Symposium on Avian Corona and Pneumoviruses and Complicating Pathogens
Publication Type: Proceedings
Publication Acceptance Date: 7/18/2014
Publication Date: 11/1/2014
Citation: Yu, Q., Hu, H., Roth, J.P., Estevez, C., Zsak, L. 2014. Generation and evaluation of recombinant Newcastle disease viruses (NDV) expressing the F and G proteins of avian metapneumovirus subtype C (aMPV-C) as bivalent vaccine against NDV and aMPV challenges in turkeys. In: 8th International Symposium on Avian Corona- and Pneumoviruses and Complicating Pathogens. 2nd Annual Meeting of the COST Action FA1207, June 17-20, 2014, Rauischholzhausen, Germany. p. 404-415.
Interpretive Summary: Virulent strains of Newcastle disease virus (NDV) and avian metapneumovirus (aMPV) can cause serious respiratory diseases in poultry. Vaccination combined with strict biosecurity practices has been the recommendation for controlling NDV and aMPV diseases in the field. Previously we generated a NDV recombinant virus expressing the glycoprotein (G) of aMPV-C as a bivalent vaccine, which provided a partial protection against aMPV-C challenge. In the present study we further engineered the NDV LaSota strain-based recombinant virus using reverse genetics technology to express the aMPV-C fusion (F) protein in addition to the G protein as a bivalent vaccine. Vaccination of turkeys with this new recombinant virus induced aMPV-C and NDV-specific antibody responses and provided significantly improved protection against pathogenic aMPV-C challenge and complete protection against velogenic NDV strain challenge. These results suggest that this recombinant virus is an improved bivalent vaccine candidate, and that expression of both the F and G protein of aMPV-C induced a stronger protective immunity against the aMPV disease.
Technical Abstract: Previously we generated a Newcastle disease virus (NDV) LaSota strain-based recombinant virus expressing the glycoprotein (G) of avian metapneumovirus subgroup C (aMPV-C) as a bivalent vaccine, which provided a partial protection against aMPV-C challenge in turkeys. To improve the vaccine efficacy, in the present study, we further engineered the LaSota/aMPV-C recombinant virus to express the aMPV-C fusion (F) protein in addition to the G protein. The resulting recombinant virus, rLS/aMPV-C F&G, was slightly attenuated in vivo, yet maintained similar cytopathic effects and virus titers in vitro when compared to the parental LaSota virus. Expression of the aMPV-C F/G protein in the recombinant virus-infected cells was detected by immunofluorescence assay. Vaccination of turkeys with rLS/aMPV-C F&G induced aMPV-C and NDV-specific antibody responses and provided improved protection against pathogenic aMPV-C challenge and complete protection against velogenic NDV CA02 strain challenge. These results suggest that the rLS/aMPV-C F&G recombinant virus is a safe and effective bivalent vaccine, and that expression of both the F and G protein of aMPV-C induced stronger protective immunity against the aMPV-C disease.