Control of Japanese encephalitis by Japanese Researchers

JEV可引起人和马的脑炎，并导致怀孕猪流产。从器官、细胞和分子水平对JEV的感染机制进行了全面的研究，DC-SIGN、DC-SIGNR和LSECtin的表达使Daudi细胞对JEV的感染敏感，但其作用依赖于用于制备JEV的细胞系的来源以及表达的分子。乙脑病毒包膜蛋白（E蛋白）的分子量在不同的细胞系中存在差异，而E蛋白上糖链的结构差异尚不清楚。这些结果提示，JEV通过叮咬感染蚊虫的皮肤，感染表达DC-SIGN分子的树突状细胞，是JEV体内感染的动力学模型。树突状细胞产生的JEV进入血流并感染其他细胞，如表达DC-SIGNR和/或LSECtin的内皮细胞。JEV E蛋白的糖修饰可能取决于感染的细胞类型，并且还影响下一个靶标。胎盘内皮细胞感染可导致猪流产。体内可存在产生JEV的细胞，其倾向于感染中枢神经系统。

JEV causes encephalitis in humans and horses and abortion in pregnant pigs. The infection mechanism of JEV was comprehensively studied to clarify JEV dynamics at the levels of organs, cells, and molecular levels.Expression of DC-SIGN, DC-SIGNR, and LSECtin, separately, made Daudi cells susceptible to JEV infection, while their effects depended on the origins of cell lines used for JEV preparation as well as the molecules expressed. Molecular weights of JEV envelope (E) protein were different among cell lines used, while structural differences of sugar chains on the E protein were unclear. Lectin-mediated infection was specifically inhibited by mannan or G1cNAcB1-2Man.These results suggest a model of JEV dynamics in vivo: JEV invades via skin-bites of infected mosquitoes and infects dendritic cells expressing DC-SIGN molecules. JEV produced by dendritic cells enters blood stream and infects other cells such as endothelial cells which express DC-SIGNR and/or LSECtin. Sugar modification of JEV E protein may depend on cell types infected and also affect a next target. Infection of placental endothelial cells may result in abortion of pigs. Cells producing JEV which tends to infect the central neuron system well could exist in vivo.