Key Laboratory of Animal Production, Product Quality and Security, Jilin Agricultural University, Changchun, 130118, China.
Liaoyuan Academy of Agricultural Sciences, Liaoyuan, 136200, China.
Fish Shellfish Immunol. 2018 Sep;80:223-231. doi: 10.1016/j.fsi.2018.05.046. Epub 2018 Jun 7.
Cyprinid herpesvirus 3 (CyHV-3) infection in carp causes a fatal and highly contagious disease that results in huge economic losses in common and koi carp aquaculture worldwide. Thus the development of an effective vaccine to protect carp stocks against the CyHV3 virus is imperative. In this study, we immunized common carps with a DNA vaccine consisting of a plasmid that co-expresses the CyHV-3 envelope protein ORF25 and the carp IL-1β gene in order to evaluate the adjuvant potential of IL-1β. Our result shows that antibodies specific to ORF25 can be detected as early as one week after intramuscular injection of the DNA vaccine at low dosage. Moreover, the co-expression of IL-1β can enhance the potency of the vaccine, as demonstrated by a higher antibody level after the third immunizations. Importantly, the DNA vaccine reduced mortality in carps when they were immunized prior to a CyHV-3 challenge, as compared to negative control groups. However, despite being able to induce higher neutralizing antibody titres, the co-expression of IL-1β in the DNA vaccine did not significantly improve the overall survival of immunized fish following virus challenge. Furthermore, the DNA vaccine can protect carps from tissue damage and histopathological alteration caused by viral infection. These strongly suggests that the vaccine can efficiently elicit protective immunity against CyHV-3 infection. In conclusion, the DNA vaccine formulated with the pIRES-ORF25-IL-1β DNA construct can protect carp against CyHV-3 infection and has potential applicability in the aquaculture industry.
鲤鱼疱疹病毒 3（CyHV-3）感染鲤鱼会导致一种致命且具有高度传染性的疾病，给全球鲤鱼和锦鲤养殖业造成巨大的经济损失。因此，开发一种有效的疫苗来保护鲤鱼种群免受 CyHV3 病毒的侵害势在必行。在这项研究中，我们用一种 DNA 疫苗对鲤鱼进行免疫，该疫苗由一个质粒组成，该质粒共表达 CyHV-3 包膜蛋白 ORF25 和鲤鱼白细胞介素-1β（IL-1β）基因，以评估 IL-1β的佐剂潜力。我们的结果表明，在低剂量肌肉内注射 DNA 疫苗后，最早可在一周内检测到针对 ORF25 的特异性抗体。此外，IL-1β的共表达可以增强疫苗的效力，这表现为第三次免疫后的抗体水平更高。重要的是，与阴性对照组相比，在 CyHV-3 攻毒前对鲤鱼进行 DNA 疫苗免疫可降低鲤鱼的死亡率。然而，尽管能够诱导更高的中和抗体滴度，但在 DNA 疫苗中表达 IL-1β并没有显著提高免疫鱼在病毒攻毒后的总体存活率。此外，DNA 疫苗可以保护鲤鱼免受病毒感染引起的组织损伤和组织病理学改变。这些强烈表明疫苗可以有效地诱导针对 CyHV-3 感染的保护性免疫。总之，用 pIRES-ORF25-IL-1β DNA 构建体配制的 DNA 疫苗可以保护鲤鱼免受 CyHV-3 感染，具有在水产养殖业中的潜在应用价值。
