近年来高致病性禽流感病毒（AIV）H5N1跨物种屏障直接感染人，致使人感染禽流感疫情不断出现，病死率近60％，造成的公共卫生危害形势严峻。然而，AIV致病机制仍不明确。本研究旨在阐明高致病性禽流感病毒H5N1非结构蛋白（NS1）诱导哺乳动物细胞的凋亡机制，采用真核表达质粒构建、细胞转染、蛋白表达、流式液相多重蛋白定量技术、线粒体膜电位检测、免疫荧光、免疫共沉淀以及microRNA生物芯片等技术手段，率先探讨NS1基因对线粒体依赖的内源性凋亡通道的激活机制，阐明Bcl-2家族成员在NS1诱导的内源性细胞凋亡通路激活过程中的表达变化及作用，明确在NS1这一凋亡信号刺激下参与凋亡调控的关键miRNA分子，为H5N1致病机制的最终揭示奠定基础。

Avian H5N1 influenza virus causes a remarkably sever disease in humans, with an overall case fatality rate close to 60%. However, the mechanism(s) of H5N1-induced diseases and death are not well understood at the present time. It has been postulated that H5N1-induced apoptosis is an important factor in pathogenesis. The nonstructural protein NS1, have been implicated in influenza virus-induced apoptosis. A detail characterization of the NS1 protein and the mechanisms involved in the induction of apoptosis is essential for understanding the pathogenesis of influenza viruses, particularly H5N1. To verify the role of H5N1-encoded NS1 in inducing apoptosis, the NS1 gene was cloned and expressed in cells such as human airway epithelial cells (NCI-H292 cells). The apoptotic events posttransfection were examined by immunofluorescence assay, ?ow cytometric measurement of propidium iodide, annexin V staining, cytometric beads array(CBA), Western blot analyses with antibodies speci?c for proapoptotic and antiapoptotic proteins, co-immunoprecipitation, mitochondrial membrane potential detection, and microRNA array. Furthermore, to investigate the activation of mitochondrial-dependent pathway of the apoptosis triggered by NS1 and to determine the key microRNAs which may be involved to regulate the expression of Bcl-2 family proteins or any other apoptotic proteins by study on the profile of microRNA expression treated by NS1 or/and apoptotic stimulations.