MOA Key Laboratory of Animal Virology, Zhejiang University Center for Veterinary Sciences, Hangzhou, China; Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; ZJU-Xinchang Joint Innovation Centre (TianMu Laboratory), Gaochuang Hi-Tech Park, Xinchang, Zhejiang, China.
Int J Biol Macromol. 2024 Oct;278(Pt 3):134955. doi: 10.1016/j.ijbiomac.2024.134955. Epub 2024 Aug 21.
As one genotype of porcine circovirus (PCV) identified in 2016, PCV3 has brought huge hidden dangers to the global swine industry together with PCV2. Virus-like particles (VLPs) of capsid protein (Cap) of PCV2 serve as an alternative nano-antigen delivery strategy to efficiently induce antiviral immune response against PCV2 and/or other covalently displayed swine pathogens. However, the current understanding is limited on the capability of PCV3 as a nano-vaccine vehicle. Here we systematically compared the characteristics and the immunogenic efficacy of PCV3 Cap (Cap3) and PCV2 Cap (Cap2) in a VLP form. Cap3 VLPs presented higher internalization efficiency into cells and cytokines production compared to those of Cap2. Meanwhile, cross-reactive immunity between Cap3 VLPs and Cap2 VLPs was detected. Furthermore, to evaluate the function of Cap3 VLPs and Cap2 VLPs as vaccine vehicles carrying foreign proteins, the non-structural protein 6 of porcine reproductive and respiratory syndrome virus (PRRSV) was fused to C-terminus of Cap. Cap3-based chimeric particles induced a higher level of nsp6-specific immune response and PRRSV inhibition. Collectively, these self-assembling, Cap-based VLPs offer a compelling platform for enhancing the effectiveness of subunit vaccinations against newly emerging diseases and hold great promise for the development of Cap3-based chimeric subunit vaccines.
2016 年鉴定的猪圆环病毒（PCV）的一个基因型 PCV3 与 PCV2 一起给全球养猪业带来了巨大的隐患。PCV2 衣壳蛋白（Cap）的病毒样颗粒（VLPs）作为替代纳米抗原传递策略，可有效诱导针对 PCV2 和/或其他共价展示的猪病原体的抗病毒免疫反应。然而，目前对 PCV3 作为纳米疫苗载体的能力的了解有限。在这里，我们系统地比较了 PCV3 Cap（Cap3）和 PCV2 Cap（Cap2）在 VLP 形式下的特性和免疫原性。Cap3 VLPs 比 Cap2 VLPs 具有更高的细胞内化效率和细胞因子产生。同时，检测到 Cap3 VLPs 和 Cap2 VLPs 之间的交叉反应性免疫。此外，为了评估 Cap3 VLPs 和 Cap2 VLPs 作为携带外源蛋白的疫苗载体的功能，将猪繁殖与呼吸综合征病毒（PRRSV）的非结构蛋白 6 融合到 Cap 的 C 末端。Cap3 为基础的嵌合颗粒诱导更高水平的 nsp6 特异性免疫反应和 PRRSV 抑制。总之，这些自组装的 Cap 基 VLPs 为增强针对新出现疾病的亚单位疫苗的有效性提供了一个有吸引力的平台，并为 Cap3 为基础的嵌合亚单位疫苗的开发提供了巨大的前景。
