Frontiers of Agricultural Science and Engineering
RR1 and RR2 gene deletion affects the immunogenicity of a live attenuated pseudorabies virus vaccine candidate in natural pig host
1. National Research Center for Veterinary Medicine, Luoyang 471003, China.2. College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, China
As virulence-determining genes, and encode the small subunit and large subunit of viral ribonucleotide reductase (RR) in pseudorabies virus which have been extensively studied in mice. However, their role in pigs has not been adequately investigated. In this study, we deleted and genes based on a / / triple gene-deleted pseudorabies virus and tested its efficacy in pigs as a vaccine candidate. The rescued virus showed similar growth properties and plaque size as its parent strain. In an animal study, the virus could elicit humoral immune responses shown by generation of gB-specific antibodies and virus neutralizing antibodies. However, vaccination could not provide protection against virulent pseudorabies virus challenge since vaccinated pigs showed clinical pseudorabies-specific syndromes. The deficiency in protection may due to the generation of late and low levels of gB antibodies and virus neutralizing antibodies.