非结构蛋白1（NS1）是目前公认的乙型脑炎病毒的一个功能神秘的蛋白，对于该蛋白在病毒复制、致病和免疫中的功能未知。NS1蛋白刺激机体产生的抗体对病毒没有中和作用，但在体内却可产生很高的保护力，关于此种免疫保护机制的研究尚未有报道。本项目中将用NS1蛋白在体外和体内刺激相关细胞，研究NS1在体内导致的血管通透性改变和在病毒致病中的功能；同时用具有保护活性的NS1蛋白单克隆抗体，与NS1互作后检测其在体外和体内对NS1蛋白相应功能的封阻作用，以及这种作用在免疫保护中发挥的功能，为阐明NS1蛋白免疫保护机制奠定良好的基础。

The non-structural protein 1 (NS1) of flavivirus was recognized as an enigmatic protein, the protein function in virus replication, pathogenicity and immuno-protection were ambiguous till now. NS1 can maintain high concentration in the vessel and stimulate high level of antibodies. These antibodies cannot neutralize virus in vitro, while have high protection rate in vivo, even higher than the neutralizing antibody. But there has no report on the mechanism of NS1 immuno-protection yet. In this project, the NS1 protein will be employed to stimulate different kinds of cells in vessel in vivo. By analysis the changes in permeability of endothelial cells, the NS1 function in viral pathopoiesis will be revealed. Meanwhile, the protective monoclonal antibody against NS1 is used to block the functional sites in NS1 protein. The effects on pathogenicity of this blocking will be detected in vivo. This project will raise a new mechanism of NS1 immuno-protection.