Single-Dose Vaccination of Recombinant Chimeric Newcastle Disease Virus (NDV) LaSota Vaccine Strain Expressing Infectious Bursal Disease Virus (IBDV) VP2 Gene Provides Full Protection against Genotype VII NDV and IBDV Challenge.

Qilong Qiao,Shiyi Zhao,Jun Zhao,Yihang Zhang,Congcong Song,Panpan Yang,Qing Huang,Mingzhen Song,Yongtao Li,Xiangdong Wang,Baiyu Wang,Zeng Wang

doi:10.3390/vaccines9121483

Qilong Qiao, Shiyi Zhao + Show 10 more

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https://doi.org/10.3390/vaccines9121483

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Journal: Vaccines	Publication Date: Dec 15, 2021
Citations: 7	License type: CC BY 4.0

Affiliation: Henan Agricultural University

Abstract

Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) are the two most important and widespread viruses causing huge economic losses in the global poultry industry. Outbreaks of genotype VII NDV and IBDV variants in vaccinated poultry flocks call for genetically matched vaccines. In the present study, a genetic matched chimeric NDV LaSota vaccine strain expressing VP2 gene of IBDV variant, rLaS-VIIF/HN-VP2 was generated for the first time, in which both the F and HN genes of LaSota were replaced with those of the genotype VII NDV strain FJSW. The cleavage site of the FJSW strain F protein in the rLaS-VIIF/HN-VP2 genome was mutated to the avirulent motif found in LaSota. Expression of IBDV VP2 protein was confirmed by western blot. The rLaS-VIIF/HN-VP2 maintained the efficient replication ability in embryonated eggs, low pathogenicity and genetic stability comparable to that of parental LaSota virus. One dose oculonasal vaccination of one-week-old SPF chickens with rLaS-VIIF/HN-VP2 induced full protection against genotype VII NDV and IBDV lethal challenge. These results indicate that the rLaS-VIIF/HN-VP2 is a promising bivalent vaccine to prevent infections of IBDV and genotype VII NDV.

Highlights

Newcastle disease virus (NDV), a member of the genus Orthoavulavirus of subfamily Avulavirinae, family Paramyxoviridae, is the causative agent of Newcastle disease which is a highly contagious and devastating avian disease causing severe economic losses in the global poultry industry [1]
To generate a chimeric LaSota with genotype VII NDV F and HN genes expressing infectious bursal disease virus (IBDV) VP2 gene, the VP2 gene from a novel IBDV Chinese variant strain SHG19 was inserted between the P and M genes of the full-length cDNA of chimeric LaSota to get the plasmid pNDFL-VII-F/HN-VP2 (Figure 1), in which the F and HN genes was replaced with those of the circulating and highly virulent Chinese genotype VII NDV strain FJSW
It is proved that the rLaSVIIF/HN-VP2 maintains the low pathogenicity as LaSota vaccine strain

Summary

Introduction

Newcastle disease virus (NDV), a member of the genus Orthoavulavirus of subfamily Avulavirinae, family Paramyxoviridae, is the causative agent of Newcastle disease which is a highly contagious and devastating avian disease causing severe economic losses in the global poultry industry [1]. Classification based on the sequence and phylogenetic analysis of the F gene further divides NDV strains into class I, with only one genotype, and class II, having up to 18 genotypes [5]. Genetic distance analysis based on the full-length F and HN genes showed that genotype VII NDV isolates had high genetic variations with genotype II LaSota vaccine [11]. Accumulating data indicated that genotype-matched vaccines provide better protection against genotypes VII NDV infection than the LaSota vaccine [11,12]. Most of the reported genotype VIImatched ND vaccine candidates were generated by modifying the sequence encoding the fusion protein (F) cleavage site of genotype VII NDV from virulent polybasic (RRQKRF) to avirulent monobasic (GRQGRL) motif using reverse genetics technique [13,14]. An alternative strategy for producing genotype matched vaccines is to replace the F and HN genes of a current commercial vaccine strain, such as LaSota [15,16,17]

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