Construction of a Triple Gene-Deleted Live Vaccine Candidate against
Pseudorabies Virus Using CRISPR/Cas9 and Cre/LoxP System-Based
Strategy
Muping Wang, Longtao Wang* and Quan Zhao*
College of Animal Sciences and Technology, Jilin Agricultural
University, 2888 Xincheng Street, Changchun 130118, China
*Corresponding author:
zhaoquan0825@163.com;
wanglongtao2005@126.com
Abstract
The immune protective effects of pseudorabies
virus (PRV) vaccines in the market have gradually reduced and they have failed
to provide complete protection against the new PRV variant.
In this study, a triple gene-deleted live PRV strain–rZDΔTK-gE-gI was
successfully constructed by simultaneously knocking out the three major
virulence genes (gE/gI and TK) with CRISPR/Cas9 and Cre/LoxP gene editing system
and low melting point agarose purification method. After challenge with
the virulent PRV variant, all the 3-week-old piglets vaccinated with the
rZDΔTK-gE-gI PRV vaccine candidate survived
without any clinical symptoms, whereas all the unvaccinated piglets exhibited
PRV respiratory and neurological signs with 100% mortality rate within 7 days
post infection. High levels of anti-gB antibodies were induced in the vaccinated
piglets after vaccination with the rZDΔTK-gE-gI
vaccine candidate, which elicited a better
immune protective effect than the classical strain Bartha-K61. Therefore,
the triple gene-deleted live PRV vaccine candidate
is expected to control the current outbreak of pseudorabies caused by the PRV
variants.
To Cite This Article:
Wang M, Wang L and Zhao Q, 2021.
Construction of a triple gene-deleted live vaccine
candidate against pseudorabies virus using CRISPR/Cas9 and Cre/LoxP system-based
strategy. Pak Vet J, 41(4): 493-498. http://dx.doi.org/10.29261/pakvetj/2021.053