Study On Liver-specific SiRNA

Objective In order to achieve tissue-specific siRNA therapy, the liver-specific siRNA in vivo expression plasmid has been investigated. It can be used for liver-specific hepatitis B treatment, overcoming a barrier about the siRNA in the clinical application. Methods we used anti-EGFP siRNA instead of the anti-HBV siRNA in this study. We got the human-α1-anti-Trypsin promoter with PCR, artificially synthesized the ApoE enhancer and siEGFP, and assemblized them to construct an new expression regulation unit, which has been cloned into and modified the eukaryotic expression vector pcDNA6-CMV-EGFP. Then the recombinant plasmid, called pcDNA6-ApoE-hAAT-siEGFP, has been transiently transfected HepG2, MDA-MB-231,293 cells respectively. Then the inhibition of siEGFP in the different cell lines have been evaluated and compared by Western-blot ananlysis. Results Both enzyme digestion and sequencing demonstrated that the recombinant plasmid pcDNA6-ApoE-hAAT-siRNA has been constructed successfully. The inhibit level of siEGFP in this modified plasmid is much more higher in HepG2 then in other non-liver cell lines. Conclution Above results verified that the liver-specific siRNA in vivo expression plasmid has been successfully constructed. If we replaced the siEGFP with anti-HBV siRNA in this modified plasmid, It is highly possible to develop a liver-specifically expressing anti-HBV siRNA therapy.