Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.
Front Immunol. 2023 Mar 21;14:1077938. doi: 10.3389/fimmu.2023.1077938. eCollection 2023.
Contagious ecthyma (Orf), an acute and highly contagious zoonosis, is prevalent worldwide. Orf is caused by Orf virus (ORFV), which mainly infects sheep/goats and humans. Therefore, effective and safe vaccination strategies for Orf prevention are needed. Although immunization with single-type Orf vaccines has been tested, heterologous prime-boost strategies still need to be studied. In the present study, ORFV B2L and F1L were selected as immunogens, based on which DNA, subunit and adenovirus vaccine candidates were generated. Of note, heterologous immunization strategies using DNA prime-protein boost and DNA prime-adenovirus boost in mice were performed, with single-type vaccines as controls. We have found that the DNA prime-protein boost strategy induces stronger humoral and cellular immune responses than DNA prime-adenovirus boost strategy in mice, which was confirmed by the changes in specific antibodies, lymphocyte proliferation and cytokine expression. Importantly, this observation was also confirmed when these heterologous immunization strategies were performed in sheep. In summary, by comparing the two immune strategies, we found that DNA prime-protein boost strategy can induce a better immune response, which provides a new attempt for exploring Orf immunization strategy.
传染性脓疱性皮炎（羊口疮）是一种世界范围内流行的急性、高度接触传染性动物传染病。羊口疮由口疮病毒（ORFV）引起，主要感染绵羊/山羊和人类。因此，需要针对羊口疮制定有效的、安全的疫苗接种策略。尽管已经对单型羊口疮疫苗进行了免疫试验，但异源初免-加强策略仍需进一步研究。本研究选择 ORFV 的 B2L 和 F1L 作为免疫原，基于此生成了 DNA、亚单位和腺病毒疫苗候选物。值得注意的是，在小鼠中进行了 DNA 初免-蛋白加强和 DNA 初免-腺病毒加强的异源免疫策略实验，以单型疫苗作为对照。我们发现，与 DNA 初免-腺病毒加强策略相比，DNA 初免-蛋白加强策略在小鼠中诱导了更强的体液和细胞免疫应答，这一结论通过特异性抗体、淋巴细胞增殖和细胞因子表达的变化得到了证实。更为重要的是，在绵羊中进行这些异源免疫策略时也得到了同样的观察结果。总之，通过比较这两种免疫策略，我们发现 DNA 初免-蛋白加强策略能够诱导更好的免疫应答，为探索羊口疮免疫策略提供了新的尝试。
