Bian Li-Jun, Tang Yu, Yang Fan, Tian Hong, Peng Qin, Tang Ming-Liang, Chen Yi-Zhen, Xia Tian, Li Shu, Zheng Hai-Xue, Shu Hong-Bing, Li Mi
Department of Infectious DiseasesMedical Research InstituteFrontier Science Center for Immunology and Metabolism, Medical Research InstituteTaikang Center for Life and Medical Sciences, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China.
State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou University, Lanzhou, China.
Vet Res. 2025 Jul 21;56(1):152. doi: 10.1186/s13567-025-01581-1.
Classical swine fever virus (CSFV) spreads in domestic and wild pig populations, causing significant economic losses in the swine industry. Despite the global implementation of live attenuated vaccines, CSFV remains a persistent threat, with sporadic outbreaks reported annually. A major limitation of the current vaccines is safety concerns and the inability to differentiate infected from vaccinated animals (DIVA). The development of DIVA-compliant vaccines is desirable for effectively controlling or eradicating classical swine fever (CSF). Here, we developed two lipid nanoparticle (LNP)-encapsulated mRNA vaccines encoding either the extracellular domain of the CSFV envelope protein E2 (E2-ECD) or its N-terminal 172-amino acid fragment (E2-ECD-N). Immunological assays in mice revealed high antigenicity and long-lasting protective antibody responses from a single dose of either the E2-ECD or E2-ECD-N mRNA vaccine. Notably, both the E2-ECD and E2-ECD-N mRNA vaccines induced robust T cell responses in mice. Furthermore, a single dose (100 μg) of the E2-ECD mRNA vaccine was sufficient to induce long-term (up to 4 months) protective immunity against CSFV infection in rabbits. Our findings highlight the potential of CSFV-E2-based mRNA vaccines as promising strategies for effective CSF prevention and control while enabling DIVA.
经典猪瘟病毒（CSFV）在家猪和野猪群体中传播，给养猪业造成重大经济损失。尽管全球都在使用减毒活疫苗，但CSFV仍然是一个持续存在的威胁，每年都有散发病例报告。当前疫苗的一个主要局限性是安全性问题以及无法区分感染动物和接种疫苗的动物（DIVA）。开发符合DIVA标准的疫苗对于有效控制或根除经典猪瘟（CSF）是可取的。在此，我们开发了两种脂质纳米颗粒（LNP）包裹的mRNA疫苗，分别编码CSFV包膜蛋白E2的胞外结构域（E2-ECD）或其N端172个氨基酸片段（E2-ECD-N）。在小鼠中进行的免疫学分析表明，单剂量的E2-ECD或E2-ECD-N mRNA疫苗具有高抗原性和持久的保护性抗体反应。值得注意的是，E2-ECD和E2-ECD-N mRNA疫苗均在小鼠中诱导了强烈的T细胞反应。此外，单剂量（100μg）的E2-ECD mRNA疫苗足以在兔子中诱导针对CSFV感染的长期（长达4个月）保护性免疫。我们的研究结果突出了基于CSFV-E2的mRNA疫苗作为有效预防和控制CSF同时实现DIVA的有前景策略的潜力。
