A live gI/gE-deleted pseudorabies virus (PRV) protects weaned piglets against lethal variant PRV challenge

• DOI: 10.1007/s11262-017-1454-y
• Publication Date: 2017-04-17T13:53:01Z
• Authors: Yue Yin; Zhiwen Xu; Xiaowan Liu; Ping Li; Fan Yang; Jun Zhao; Yi Fan; Xiangang Sun; Ling Zhu
• Keywords: Swine Diseases; 0301 basic medicine; Pseudorabies; Swine; Viral Vaccines; Weaning; Antibodies, Viral; Vaccines, Attenuated; Herpesvirus 1, Suid; 3. Good health; 03 medical and health sciences; Viral Envelope Proteins; Animals; Gene Deletion

Emerging pseudorabies virus (PRV) variant has led to frequent outbreaks of PRV infection among Bartha-K61-vaccinated swine population in Chinese swine farms and caused high mortality in pigs of all age since late 2011. Here, we generated a gE/gI-deleted PRV (rPRVXJ-delgI/gE-EGFP) based on PRV variant strain (PRV-XJ) through homologous DNA recombination. Compared to parental strain, rPRVXJ-delgI/gE-EGFP showed similar growth kinetics in vitro. Its safety and immunogenicity were evaluated in weaned piglets. Our results showed that piglets immunized with rPRVXJ-delgI/gE-EGFP did not exhibit any clinical symptoms, and a high level of gB-specific antibody was detected. After lethal challenge with variant PRV (PRV-FJ strain), all vaccinated piglets survived without showing any clinical symptoms except slight fever within 7 days post-challenge. In unvaccinated piglets, typical clinical symptoms of pseudorabies were observed, and the piglets were all died at 5 days post-challenge. These results indicated that a live rPRVXJ-delgI/gE-EGFP vaccine could be a maker vaccine candidate to control the currently epidemic pseudorabies in China.