[DNAzymes in vitro inhibit the expression of hepatitis B virus genes].

OBJECTIVE

To evaluate the inhibition effects of DNAzymes specific to Hepatitis B Virus(HBV) s gene and e gene on the expressions of Hepatitis B surface antigen(HBsAg) and Hepatitis B e antigen(HBeAg).

METHODS

DNAzymes DrzBS and DrzBC specific to HBV s gene ORF A157UG and e gene ORF A1816UG, respectively, were designed and synthesized. The inhibition effects of DrzBS or DrzBC on the expressions of HBV s and e genes were observed in 2.2.15 cells.

RESULTS

The expression of HBV s or e genes was dramatically depressed after 2.2.15 cells treated by DrzBS or DrzBC. The concentration for effective inhibition was within 0.1-2.5 micromol/L and the inhibition showed a dose dependence within that concentration range. The maximum inhibition was 94.2% and 91.8% for DrzBS and DrzBC, respectively. The inhibition was maintained for 72 hours. The efficiency of inhibiting HbsAg, HbeAg in 2.2.15 cells by DrzBS, DrzBC was higher than that by antisense oligonucleotides for the same target genes. The concentrations for effective inhibition of the DNAzymes were at least 10-fold lower compared with antisense oligonucleotides. Neither inhibition on the replication of HBV DNA nor toxicity to 2.2.15 cells was observed.

CONCLUSION

DrzBS and DrzBC can highly block the expressions of HBV s gene and e gene in 2.2.15 HBV cell model and are proved a specific and effective anti-HBV gene therapeutic means.