College of Animal and Veterinary Sciences, Southwest Minzu University, Chengdu, 610041, China.
College of Animal and Veterinary Sciences, Southwest Minzu University, Chengdu, 610041, China; Key laboratory of Ministry of Education and Sichuan Province for Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Chengdu, 610041, China.
Microb Pathog. 2024 Sep;194:106795. doi: 10.1016/j.micpath.2024.106795. Epub 2024 Jul 15.
Feline coronavirus (FCoV) infection is a leading cause of death in cats. In this study, we produced FCoV-I virus-like particles (VLPs) containing E, M, N, and S proteins using a baculovirus expression system and mixed VLPs with the adjuvants MF59 and CpG 55.2 to prepare an VLP/MF59/CpG vaccine. After immunization of mice with the vaccine, IgG specific antibodies titers against S and N proteins increased to 1:12,800, and IFN-γ and IL-4 splenocytes were significantly increased. Following immunization of FCoV-negative cats, the S protein antibodies in immunized cats (5/5) increased significantly, with a peak of 1:12,800. Notably, after booster vaccination in FCoV-positive cats, a significant reduction in viral load was observed in the feces of partial cats (4/5), and the FCoV-I negative conversion was found in two immunized cats (2/5). Therefore, the VLP/MF59/CpG vaccine is a promising candidate vaccine to prevent the FCoV infection.
猫冠状病毒（FCoV）感染是导致猫死亡的主要原因之一。在这项研究中，我们使用杆状病毒表达系统生产了含有 E、M、N 和 S 蛋白的 FCoV-I 病毒样颗粒（VLPs），并将 VLPs 与佐剂 MF59 和 CpG 55.2 混合，制备了 VLP/MF59/CpG 疫苗。用该疫苗对小鼠进行免疫后，针对 S 和 N 蛋白的 IgG 特异性抗体滴度增加到 1:12800，IFN-γ 和 IL-4 脾细胞明显增加。对 FCoV 阴性猫进行免疫后，免疫猫（5/5）的 S 蛋白抗体显著增加，峰值为 1:12800。值得注意的是，在 FCoV 阳性猫中进行加强免疫后，部分猫（4/5）粪便中的病毒载量显著降低，并且在 2 只免疫猫（2/5）中发现了 FCoV-I 阴性转换。因此，VLP/MF59/CpG 疫苗是预防 FCoV 感染的一种有前途的候选疫苗。
