State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan 430070, China.
Vaccine. 2018 Nov 19;36(48):7353-7360. doi: 10.1016/j.vaccine.2018.10.030. Epub 2018 Oct 23.
The glycoprotein E2 of classical swine fever virus (CSFV) is a major immunogenic protein that induces neutralizing antibodies and protective immunity. Thus, E2 is a suitable target antigen for the development of genetically engineered CSFV vaccines. However, these vaccines cannot generate complete protective immunity in their hosts, thereby limiting the scope of applications under field conditions. IFN-γ is an immune adjuvant that has been shown to enhance antigen immune response in various experimental models. In this study, porcine IFN-γ was used to improve the immunogenicity of the CSFV E2 subunit vaccine in pigs. Pigs were immunized with E2 subunit vaccine alone or in combination with IFN-γ. Results demonstrated that porcine IFN-γ did not enhance the CSFV-specific antibody and neutralizing antibody titers compared with the E2 subunit vaccine alone. However, co-administration of the E2 and IFN-γ subunit vaccines significantly enhanced the CSFV-specific IFN-γ expression. These findings indicated that porcine IFN-γ can increase cellular immune responses to E2 protein in pigs. Furthermore, co-immunization with E2 + IFN-γ subunit vaccine and C-strain conferred complete protection against CSFV. In contrast, E2 subunit vaccines provided incomplete protection in pigs. These results indicated that using IFN-γ as an adjuvant with CSFV E2 subunit vaccines can enhance the specific protective immune response. Therefore, E2 + IFN-γ subunit vaccine is a promising marker vaccine candidate for the control and eradication of CSF.
猪瘟病毒（Classical swine fever virus，CSFV）的糖蛋白 E2 是一种主要的免疫原性蛋白，可诱导中和抗体和保护性免疫。因此，E2 是开发基因工程 CSFV 疫苗的合适靶抗原。然而，这些疫苗不能在宿主中产生完全的保护免疫，从而限制了其在现场条件下的应用范围。IFN-γ 是一种免疫佐剂，已在各种实验模型中证明可增强抗原免疫反应。在本研究中，猪 IFN-γ 被用于增强 CSFV E2 亚单位疫苗在猪中的免疫原性。猪单独用 E2 亚单位疫苗或与 IFN-γ 联合免疫。结果表明，与单独使用 E2 亚单位疫苗相比，猪 IFN-γ 并未增强 CSFV 特异性抗体和中和抗体滴度。然而，E2 和 IFN-γ 亚单位疫苗的共同给药显著增强了 CSFV 特异性 IFN-γ 的表达。这些发现表明，猪 IFN-γ 可以增加猪对 E2 蛋白的细胞免疫反应。此外，E2+IFN-γ 亚单位疫苗与 C 株共同免疫可完全保护猪免受 CSFV 感染。相比之下，E2 亚单位疫苗在猪中提供不完全保护。这些结果表明，使用 IFN-γ 作为 CSFV E2 亚单位疫苗的佐剂可以增强特异性保护免疫反应。因此，E2+IFN-γ 亚单位疫苗是控制和消灭猪瘟的有前途的标记疫苗候选物。
