Location: Endemic Poultry Viral Diseases ResearchTitle: Engineered newcastle disease virus expressing the F and G protein of AMPV-C confers protection against challenges in turkeys. Author
|Hu, Haixia - Southwest University|
|Roth, Jason - Merial, Ltd|
Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/10/2017
Publication Date: 6/22/2017
Citation: Hu, H., Roth, J., Zsak, L., Yu, Q. 2017. Engineered newcastle disease virus expressing the F and G protein of AMPV-C confers protection against challenges in turkeys. Scientific Reports. 7:4025. http://doi:10.1038/s41598-017-04267-7.
Interpretive Summary: Avian metapneumovirus (aMPV) causes turkey rhinotracheitis (TRT), an acute upper respiratory tract infection of turkeys, and is associated with swollen head syndrome (SHS) in chickens and egg production losses in layers, resulting in substantial economic losses to the poultry industry worldwide. Currently used live attenuated vaccines appear to be effective, but the virulence reversion of these live vaccines is concerned. Therefore, there is a need to develop a safe, stable and readily administered next generation vaccine against aMPV disease. In the present study, we generated and evaluated Newcastle disease virus (NDV) LaSota vaccine strain-based recombinant viruses expressing both of the fusion (F) protein and glycoprotein (G) of aMPV subtype C as a bivalent vaccine. Vaccination of turkeys with this vaccine candidate conferred significant protection against pathogenic aMPV-C challenge and complete protection against virulent NDV strain challenge. These results suggest that this NDV/aMPV-C recombinant virus is a safe and effective aMPV-C vaccine candidate.
Technical Abstract: Avian metapneumovirus (aMPV) infects the respiratory and reproductive tracts of domestic poultry, which may develop into secondary infections that can result in substantial economic losses for producers. Live attenuated vaccines appear to be the most effective in countries where the disease is prevalent. However, reversion to virulence has been demonstrated in several studies. Therefore, the development of a stable and safe next generation vaccine against the aMPV disease is needed. Previously, we generated Newcastle disease virus (NDV) LaSota vaccine strain-based recombinant viruses expressing the glycoprotein (G) of aMPV subtype A, B, and C as bivalent vaccines, which conferred partial protection against homologous aMPV challenge in turkeys. In the present study, we further engineered the rLS/aMPV-C G virus to express the aMPV-C fusion (F) protein, in addition to the G protein, to improve vaccine efficacy. The resulting recombinant virus, rLS/aMPV-C F&G, was slightly attenuated in vivo, yet maintained similar characteristics in vitro when compared to the parental LaSota virus. Expression of the aMPV-C F/G protein in cell culture was detected by immunofluorescence assay. Turkeys vaccinated with rLS/aMPV-C F&G induced both aMPV-C and NDV-specific antibody responses, improved protection against pathogenic aMPV-C challenge, and provided 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 candidate and that the expression of both F and G proteins of aMPV-C induces a stronger protective response against the aMPV-C disease.