Generation of a genotype VII Newcastle disease virus vaccine candidate with high yield in embryonated chicken eggs

Avian Dis. 2011 Sep;55(3):391-7. doi: 10.1637/9633-122410-Reg.1.

Abstract

To generate a genotype VII Newcastle disease virus (NDV) vaccine with high yield in embryonated chicken eggs, we selected genotype VII NDV strain JS5/05, which possesses a high virus titer in embryos as the parental virus. Using reverse genetics, we generated a genetically tagged derivative (NDV/AI4) of JS5/05 by changing the amino acid sequence of the cleavage site of the F0 protein. Pathogenicity tests showed that NDV/AI4 was completely avirulent. NDV/AI4 was genetically stable and replicated efficiently during 10 consecutive passages in embryos. More importantly, serologic assays showed that oil-emulsion NDV/AI4 induced higher hemagglutination inhibition (HI) titers against the prevalent virus than oil-emulsion LaSota vaccine in chickens and geese. Moreover, NDV/AI4-induced HI titers rose faster than those elicited by LaSota in chickens. Both NDV/AI4 and LaSota provided protection against clinical disease and mortality after the challenge with the genotype VII NDV strain JS3/05. However, NDV/AI4 significantly reduced virus shedding from the vaccinated birds compared to LaSota. Taken together, these results suggest that NDV/AI4 can provide better protection than LaSota and is a promising vaccine candidate against genotype VII NDV.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chick Embryo
  • Chickens
  • Geese
  • Genotype
  • Hemagglutination Inhibition Tests
  • Newcastle Disease / prevention & control*
  • Newcastle disease virus / genetics*
  • Newcastle disease virus / pathogenicity*
  • Vaccines, Attenuated / genetics
  • Vaccines, Attenuated / immunology
  • Viral Fusion Proteins / genetics
  • Viral Vaccines / genetics
  • Viral Vaccines / immunology*
  • Virulence
  • Virus Shedding

Substances

  • Vaccines, Attenuated
  • Viral Fusion Proteins
  • Viral Vaccines