呼吸道合胞病毒（RSV）为副粘病毒科肺炎病毒属的单负链RNA病毒，已被认为与儿童急性脑病和CNS症状有关。活化的中枢神经元和小胶质细胞TLRs在多种形式的CNS损害中起重要作用，但RSV如何感染中枢神经元及其损伤的机制，目前尚不清楚。TLR4和新发现的核仁素能识别RSV F蛋白，TLR7和3能识别病毒RNA；中枢神经元和小胶质细胞表面同时表达有TLR4和核仁素。因此本项目拟在细胞模型上运用TLR4/核仁素siRNA干扰和Transwell共培养技术，用激光共聚焦、流式细胞术、分子生物学等方法，检测F-受体的结合和表达、细胞活力和凋亡、炎性因子及病毒增殖水平等，研究F蛋白与其共受体的相互作用、TLR7/3活化、RSV激活小胶质细胞分泌炎性因子对中枢神经元的影响，以阐明RSV感染中枢神经元及其损伤机制。对完善RSV与细胞的相互作用理论，作为分子靶标用于RSV脑病的快速诊断和治疗，具有重要意义。

Respiratory syncytial virus (RSV) is a single negative-strand RNA virus of Paramyxoviridae pneumonia family, has been known to be associated with acute encephalopathy in children, and is related with central nervous system symptoms. Some researches have demonstrated that activation of Toll-like receptors (TLRs) expressed on the central neurons and microglia cells play important roles in various kinds of damages in central nervous system. But the mechanisms how RSV infects central neurons and injury central neuronal cells have not yet been clearly. Recently, we knew that TLR4 and nucleolin, a newly discovered receptor as a functional receptor for RSV F protein, all expressed on the surface of cells could recognize the RSV F protein, respectively. And TLR7 and TLR3 could recognize viral single-stranded RNA and double-stranded RNA produced in the course of RSV replication, respectively. Meanwhile central neurons and microglia cells all express TLR4 and nucleolin receptors. So in the current project we will intend to use siRNA interference for TLR4 and nucleolin receptors and Transwell co-culture technology in the cell models, combining with other methods such as laser confocal microscopy, flow cytometry and molecular biology techniques etc, to detect F-TLR4 and F-nucleolin combination, receptors expression, the vitality and apoptosis of central neurons, the levels of inflammatory cytokines and viral titers. To study the interaction between F protein and its co-receptors, activation of TLR7 and TLR3, and neuronal damage caused by a number of inflammatory cytokines released from RSV activating microglia. We will hope to illustrate how RSV infects central neurons and its injury mechanisms. It will be of great importance in the completing theory of interaction between RSV and host cells and in the rapid diagnosis and effective treatment of human RSV associated encephalopathy by utilizing these molecular targets.