Feline coronavirus (FCoV) is an unsegmented, single-stranded RNA virus belonging to the genus. It can cause fatal feline infectious peritonitis (FIP) in cats of any ages. Currently, there are no effective prevention and control measures to against FCoV. In this study, we developed a recombinant adenovirus vaccine, AD5-N, based on the nucleocapsid(N) protein of FCoV. The immunogenicity of AD5-N was evaluated through intramuscular immunization in 6-week-old Balb/c mice and 9–12 months old cats. Compared to the control group, AD5-N specifically induced a significant increase in IgG and SIgA levels in the vaccinated mice. Furthermore, AD5-N not only effectively promoted strong cellular immune responses in cats but also induced high levels of specific SIgA, effectively helping cats resist FCoV infection. Our findings suggest that adenovirus vector vaccines based on the N gene have the potential to become candidate vaccines for the prevention and control of FCoV infection.

中文翻译：

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基于猫冠状病毒 N 蛋白的腺病毒载体疫苗可引发强大的保护性免疫反应

猫冠状病毒（FCoV）是一种不分节段的单链RNA病毒，属于该属。它可以在任何年龄段的猫中引起致命的猫传染性腹膜炎（FIP）。目前，针对FCoV尚无有效的防控措施。在这项研究中，我们开发了一种基于 FCoV 核衣壳 (N) 蛋白的重组腺病毒疫苗 AD5-N。通过对 6 周大的 Balb/c 小鼠和 9-12 个月大的猫进行肌内免疫来评估 AD5-N 的免疫原性。与对照组相比，AD5-N 特异性诱导接种小鼠的 IgG 和 SIgA 水平显着增加。此外，AD5-N不仅能有效促进猫体内强烈的细胞免疫反应，还能诱导高水平的特异性SIgA，有效帮助猫抵抗FCoV感染。我们的研究结果表明，基于N基因的腺病毒载体疫苗有潜力成为预防和控制FCoV感染的候选疫苗。