反义寡聚硫代磷酸脱氧核苷抑制体外细胞培养系统中乙肝抗原表达的研究

Studies on Inhibition of Antisense Phosphorothioate Oligodeoxynucleotides on Expression of HBsAg and HBeAg in Cell Culture System

设计合成了两个分别互补于乙肝病毒2.1kb mRNA起始区(片段A)和增强子区(片段B)的硫代磷酸的DNA片段。在经克隆HBV DNA转染HepG_2细胞建立的HBV短暂表达系统及稳定产生HBV的2215细胞中研究二者对HBsAg及HBeAg表达的抑制作用。结果表明反义寡聚物能不同程度抑制乙肝抗原表达,并与剂量呈一定正相关。在HepG_2细胞HBV短暂表达系统中,6μmol/L浓度时,片段A、B对HBsAg的抑制作用分别为60％,56.1％,对HBeAg表达的抑制水平分别为45％、48％。在2215细胞中,18μmol/L浓度时,二者对HBsAg及HBeAg的抑制作用只有20～35％左右。同时采用甲基蓝四氮唑(MTT)方法检测了反义寡聚物对HepG_2细胞活性的影响,在高浓度40μmol/L时才呈现15％左右的抑制作用,这表明其抑制乙肝抗原的表达是高选择性的。

Antisense phosphorothioate oligodeoxynueleotides respectively complementary to initial region of 2.1kb mRNA(oligomer A,14nts)and enhancer I(oligomer B,12nts)of HBV were synthesed by chemi cal synthetic method,and inhibition of these oligomers on expression of HBsAg and HBeAg in cell cul ture system was studied. The oligomer A inhibited more than 50％ of HBsAg at 3μmol/L, but the oligomer B did at 6μmol/L. On the contrary,the oligomer B showed 35％ inhibition on expression of HBeAg at 3μmol/L,but 22% the oligomer A at the same conc. in HepG_2 cell transfected with cloned HBV DNA. However, they could only inhibit 20-35% expression of HBsAg and HBeAg at 18μmol/L in 2215 cell line. In the meantime, the results showed that the oligomer A possessed little inhibition on metabolic activity of HepG_2 cell at 40μmol/L by MTT method. The results suggest that antisense oligomers could specifically inhibit expression of HBsAg and HBeAg,and be considered as a unique class of experimental therapeutic agents against infection of hepatitis B virus.