新型siRNA抗流感病毒活性的研究

Study on the activity of novel siRNAs against influenza virus

目的设计合成具有广谱性抗流感病毒活性的siRNA,分别在细胞内和小鼠体内进行活性评价。方法从甲型流感病毒毒株A/WSN/33的基因(PB2、PB1、PA、M、NS)中提取高度保守的序列设计合成siRNA。通过293T-Gluc系统和单轮感染流感病毒系统对siRNA进行活性筛选。然后在细胞水平检测siRNA对流感病毒复制的抑制作用,并且经雾化给药途径对siRNA的体内抗流感活性进行评价。结果活性筛选得到4条具有50%以上抑制活性的siRNA(siPB2-1、siPB2-2、siPB1-2和siNS-1),EC50值在0.4~1.3 nmol/L之间。4条siRNA对另外两株A/PR/8/34和B/Beijinghaidian/1386/2013(Victoria系)流感病毒均表现出较好的抑制活性。动物实验表明,siPB2-1经雾化给药途径可以对流感病毒感染的小鼠产生一定的保护作用。结论新合成的siRNA在细胞水平和小鼠体内均具有良好的抗流感病毒活性。

Objective To design and synthesize the novel si RNAs with universal anti-influenza virus activity which was measured both in vitro and in vivo. Methods The si RNAs were designed targeting at the highly conserved fragments of PB2, PB1, PA, M and NS gene of A/WSN/33 strain. The anti-virus activity screening of si RNAs was carried out with 293T-Gluc system and single-infectious influenza virus sequentially. And the inhibitory effect of si RNAs on influenza virus replication was detected in vitro. Then the in vivo activity of si RNAs was valued in mice by aerosolization delivery. Results 4 siRNAs of siPB2-1, siPB2-2, siPB1-2 and siNS-1 were screened out with above 50% inhibitory activity. The EC50 values of si RNAs are between 0.4 to 1.3 nmol/L. The siRNAs also inhibited the replication of another two strains of A/PR/8/34 and B/Beijinghaidian/1386/2013（Victoria lineage）. The animal experiment showed that siPB2-1 protected mice from influenza virus infection via aerosolization delivery. Conclusion The independent designed siRNAs possess high anti-influenza virus activity both in vitro and in vivo.