Wang Shanghui, Han Longfei, Yu Jimin, Ye Guangqiang, Liu Hongyang, Liu Yunfei, Zhou Qiongqiong, Zhang Zhaoxia, Weng Changjiang
State Key Laboratory for Animal Disease Control and Prevention, Division of Fundamental Immunology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150069, China.
College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou 311300, China.
Vaccines (Basel). 2025 Mar 27;13(4):359. doi: 10.3390/vaccines13040359.
Since 2011, re-emerging pseudorabies virus (PRV) variant strains have been widespread in swine herds immunized with the classical PRV vaccine in China, suggesting that it is necessary to develop a new vaccine against these PRV variant strains. Here, based on a PRV mutant strain isolated in Jinmen (JM), two recombinant strains were constructed using CRISPR/Cas9 technology, including PRV-JM-ΔEK with the deletion of the and genes and PRV-JM-ΔEI92K with the deletion of the , , , , and genes. A one-step growth curve and plaque assay revealed that the cell-to-cell transmission ability of PRV-JM-ΔEI92K was lower than that of PRV-JM-ΔEK. However, the replication ability of PRV-JM-ΔEI92K was approximately 10 times higher than that of PRV-JM-ΔEK, similar to wild-type PRV-JM. The intramuscular injection of 10 TCID of PRV-JM-ΔEK or PRV-JM-ΔEI92K could not cause death in mice, and both could produce specific antibodies against gB and gD. The survival rate of mice immunized with both recombinant viruses was 100% when the mice were challenged by the PRV-JM strain. Histopathological sections from the PRV-JM-ΔEK group showed milder pathological changes compared to the PRV-JM-ΔEI92K group, proving that PRV-JM-ΔEK provided more effective protection. In pigs injected with 10 TCID of PRV-JM-ΔEK or PRV-JM-ΔEI92K, their body temperature did not rise, and their weight gain was not affected. Both recombinant viruses could induce the production of gB- and gD-specific antibodies and neutralizing antibodies. After the challenge of the PRV-JM virus, neutralizing antibody production was rapidly induced and lasted for at least 3 weeks. Pigs immunized with both PRV-JM-ΔEI92K and PRV-JM-ΔEK had a 100% survival rate, demonstrating that both recombinant viruses could provide effective protection. Compared with PRV-JM-ΔEK, PRV-JM-ΔEI92K had better safety. In conclusion, we constructed two PRV recombinant viruses, which have the potential to be used as a live carrier vaccine.
自2011年以来，重新出现的伪狂犬病病毒（PRV）变异株在中国用经典PRV疫苗免疫的猪群中广泛传播，这表明有必要研发一种针对这些PRV变异株的新型疫苗。在此，基于在金门分离的一株PRV突变株（JM），利用CRISPR/Cas9技术构建了两种重组毒株，包括缺失了 和 基因的PRV-JM-ΔEK以及缺失了 、 、 、 和 基因的PRV-JM-ΔEI92K。一步生长曲线和蚀斑试验表明，PRV-JM-ΔEI92K的细胞间传播能力低于PRV-JM-ΔEK。然而，PRV-JM-ΔEI92K的复制能力比PRV-JM-ΔEK高约10倍，与野生型PRV-JM相似。肌肉注射10 TCID的PRV-JM-ΔEK或PRV-JM-ΔEI92K不会导致小鼠死亡，且两者均可产生针对gB和gD的特异性抗体。当用PRV-JM株攻击小鼠时，用两种重组病毒免疫的小鼠存活率均为100%。与PRV-JM-ΔEI92K组相比，PRV-JM-ΔEK组的组织病理学切片显示病理变化较轻，证明PRV-JM-ΔEK提供了更有效的保护。在注射10 TCID的PRV-JM-ΔEK或PRV-JM-ΔEI92K的猪中，它们的体温没有升高，体重增加也未受影响。两种重组病毒均可诱导产生gB和gD特异性抗体以及中和抗体。在用PRV-JM病毒攻击后，迅速诱导产生中和抗体并持续至少3周。用PRV-JM-ΔEI92K和PRV-JM-ΔEK免疫的猪存活率均为100%，表明两种重组病毒均可提供有效的保护。与PRV-JM-ΔEK相比，PRV-JM-ΔEI92K具有更好的安全性。总之，我们构建了两种PRV重组病毒，它们有潜力用作活载体疫苗。
