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目的:研究槲皮素体外抗呼吸道合胞病毒（respiratory syncytial virus，RSV）的作用，为新型抗呼吸道合胞病毒中药开发提供基础研究数据。方法:根据细胞毒性实验确定槲皮素的最大工作浓度，采用病毒滴度TCIDn 50检测法、细胞毒性检测法、Western blot和实时荧光定量PCR（qPCR）方法检测槲皮素体外对RSV的增殖、蛋白表达和基因转录抑制效果。采用RNA干扰敲低HSP70表达水平，检测病毒的生长曲线。n 结果:槲皮素对Vero细胞的毒性呈现明显的梯度依赖效应，最大无毒浓度为25 μM，且12 μM的槲皮素浓度下，细胞上清中病毒滴度抑制率达60%；同时Western blot结果显示槲皮素处理的细胞中病毒F蛋白受到显著抑制；qPCR对细胞中RSV G蛋白的转录本的检测结果表明槲皮素使病毒G蛋白的转录效率下降了85%以上。敲低HSP70的表达水平后，病毒的滴度下降了两个数量级。结论:槲皮素体外对RSV-A有较好的抗病毒作用，且可能是通过抑制其特异性底物HSP70实现的。“,”Objective:To study the effect of quercetin on respiratory syncytial virus (RSV) n in vitro, so as to provide basic data for the development of new traditional Chinese medicine against respiratory syncytial virus.n Methods:According to the maximum working concentration of quercetin determined by cytotoxcity assay, the n in vitro effects of quercetin on RSV proliferation, protein expression and gene transcriptional inhibition were analyzed by TCIDn 50 assay, cytotoxicity assay, Western blot and real-time fluorescent quantitative PCR (qPCR). The growth curve of the virus was tested using RNAi to knock-down the expression of Hsp70.n Results:Toxicity of quercetin on Vero cells showed an obvious gradient dependent effect, with the maximum non-toxic concentration of 25 μM. The inhibition rate of virus titer in the cells supernatant reached 60% at the quercetin concentration of 12 μM. Meanwhile, Western blot results showed that the virus F protein in cells treated with quercetin was significantly inhibited. The results of qPCR on the transcript of RSV G protein in cells showed that quercetin reduced the transcription efficiency of virus G protein by more than 85%. Knocking down the expression level of HSP70 reduced the titer of the virus by two orders of magnitude.Conclusions:Quercetin has a good antiviral effect on RSV-A n in vitro, and may be achieved by inhibiting its specific substrate HSP70.n