Data_Sheet_1_The Infection of the Japanese Encephalitis Virus SA14-14-2 Strain Induces Lethal Peripheral Inflammatory Responses in IFNAR Deficiency Mice.zip

The Japanese encephalitis virus (JEV) is a leading cause of mosquito-borne viral encephalitis worldwide. Clinical symptoms other than encephalitis, on the other hand, are substantially more prevalent with JEV infection, demonstrating the relevance of peripheral pathophysiology. We studied the peripheral immunopathogenesis of JEV using IFNAR deficient (IFNAR–/–) mice infected with the SA14-14-2 strain under the BSL-2. The body weight and survival rate of infected-IFNAR–/–mice decreased significantly. Infected-IFNAR–/–mice’s liver and spleen demonstrated obvious tissue damage and inflammatory cell infiltration. There was also extensive viral replication in the organs. IFN-α/β protein expression was dramatically elevated in peripheral tissues and serum, although the related interferon-stimulated genes (ISGs) remained low in the spleen and liver of infected-IFNAR–/–animals. Consistently, the differentially expressed genes (DEGs) analysis using RNA-sequencing of spleens showed inflammatory cytokines upregulation, such as IL-6, TNF-α, and MCP-1, and IFN-γ associated cytokine storm. The infiltration of macrophages and neutrophils in the spleen and liver of SA14-14-2-infected IFNAR–/– mice was dramatically elevated. However, there was no significant difference in tissue damage, viral multiplication, or the production of IFNα/β and inflammatory cytokines in the brain. Infection with the JEV SA14-14-2 strain resulted in a lethal peripheral inflammatory response and organ damage without encephalitis in IFNAR–/– mice. Our findings may help shed light on the peripheral immunopathogenesis associated with clinical JEV infection and aid in developing treatment options.

日本脑炎病毒（Japanese encephalitis virus, JEV）是全球范围内引发虫媒病毒性脑炎的首要病原体。然而，除脑炎外的临床症状在JEV感染中更为普遍，这凸显了外周病理生理学的研究价值。本研究在生物安全二级（BSL-2）实验室条件下，以感染SA14-14-2毒株的IFNAR缺陷型（IFNAR–/–）小鼠为模型，探究JEV的外周免疫发病机制。结果显示，感染病毒的IFNAR–/–小鼠体重与生存率均显著下降；肝脏与脾脏出现明显组织损伤及炎性细胞浸润，各脏器中还存在广泛的病毒复制。外周组织与血清中的干扰素-α/β（IFN-α/β）蛋白表达显著升高，但感染小鼠的脾脏与肝脏内相关干扰素刺激基因（interferon-stimulated genes, ISGs）的表达水平仍处于较低状态。与之相符的是，对脾脏进行RNA测序后的差异表达基因（differentially expressed genes, DEGs）分析表明，IL-6、TNF-α、MCP-1等炎性细胞因子以及与IFN-γ相关的细胞因子风暴相关基因均出现上调。SA14-14-2毒株感染的IFNAR–/–小鼠脾脏与肝脏中，巨噬细胞与中性粒细胞的浸润程度显著升高。但小鼠脑部的组织损伤、病毒增殖以及IFN-α/β与炎性细胞因子的产生均无显著差异。综上，感染JEV SA14-14-2毒株可使IFNAR–/–小鼠出现致死性外周炎性反应与脏器损伤，且不伴随脑炎症状。本研究结果有助于阐明临床JEV感染相关的外周免疫发病机制，并为治疗方案的开发提供参考。