Tian Xiaoxiao, Wang Haojie, Song Hao, Wei Ziyi, Zhu Xulong, Liu Guoqing, Sun Mingxia, Huang Xinyi, Chen Meng, Tang Yandong, Wang Haiwei, Yang Yongbo, An Tongqing
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150069, China.
Heilongjiang Veterinary Biopharmaceutical Engineering Technology Research Center, Harbin, 150069, China.
Vet Res. 2025 Aug 5;56(1):162. doi: 10.1186/s13567-025-01592-y.
Pseudorabies virus (PRV) and porcine parvovirus type 1 (PPV1) are major pathogens that cause reproductive disorders in sows, and mixed infections are frequently detected on pig farms. In this study, a recombinant PRV (rPRV-VP2) based on a PRV variant (HLJ8) was constructed to express the PPV1 VP2 protein. To ensure safety, four virulence genes (TK, gE, gI, and UL39) of PRV HLJ8 were deleted, followed by further evaluation of safety and immunogenicity in piglets. The PPV1 VP2 expression cassette was inserted into the gE/gI deletion site, enabling successful expression of the VP2 protein, which exhibited hemagglutination activity with a titre of 1:64. Animal experiments demonstrated that rPRV-VP2 elicited robust antibody responses against both PRV and PPV1, providing complete protection in both mice and piglets. Compared with commercial PRV and PPV1 vaccines, rPRV-VP2 conferred comparable or superior protection, resulting in not only no clinical symptoms but also significantly reduced viral loads in tissues. The deletion of the gE gene can distinguish wild-type virus infection from vaccine immunity in clinical applications. Overall, rPRV-VP2 offers a safe and effective strategy for dual protection against PRV and PPV1, reducing vaccination costs in pig production.
伪狂犬病病毒（PRV）和1型猪细小病毒（PPV1）是导致母猪繁殖障碍的主要病原体，猪场中经常检测到混合感染。在本研究中，构建了一种基于PRV变异株（HLJ8）的重组PRV（rPRV-VP2）以表达PPV1 VP2蛋白。为确保安全性，删除了PRV HLJ8的四个毒力基因（TK、gE、gI和UL39），随后在仔猪中进一步评估安全性和免疫原性。将PPV1 VP2表达盒插入gE/gI缺失位点，成功表达了VP2蛋白，其血凝活性效价为1:64。动物实验表明，rPRV-VP2引发了针对PRV和PPV1的强烈抗体反应，在小鼠和仔猪中均提供了完全保护。与市售PRV和PPV1疫苗相比，rPRV-VP2提供了相当或更好的保护，不仅没有临床症状，而且组织中的病毒载量显著降低。gE基因的缺失在临床应用中可区分野生型病毒感染和疫苗免疫。总体而言，rPRV-VP2为PRV和PPV1的双重保护提供了一种安全有效的策略，降低了生猪生产中的疫苗接种成本。
