Viral Hepatitis
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 21, 2005; 11(23): 3504-3507
Published online Jun 21, 2005. doi: 10.3748/wjg.v11.i23.3504
Effective inhibition of expression of hepatitis B virus genes by DNAzymes
Jian-Er Wo, Xiao-Ling Wu, Lin-Fu Zhou, Hang-Ping Yao, Li-Wei Chen, Reinhard H. Dennin
Jian-Er Wo, Lin-Fu Zhou, Hang-Ping Yao, Li-Wei Chen, Key Laboratory of Infectious Diseases, Ministry of Public Health of China; Institute of Infectious Diseases, First Affiliated Hospital, Medical College of Zhejiang University, Hangzhou 310003, Zhejiang Province, China
Xiao-Ling Wu, Medical School, Hangzhou Normal College, Hangzhou 310012, Zhejiang Province, China
Reinhard H. Dennin, Institute of Medical Microbiology and Hygiene, University of Luebeck, Luebeck D-23538, Germany
Author contributions: All authors contributed equally to the work.
Correspondence to: Dr. Jian-Er Wo, Institute of Infectious Diseases, First Affiliated Hospital, Medical College of Zhejiang University, Qingchun Road 79, Hangzhou 310003, Zhejiang Province, China. wojianer@zju.edu.cn
Telephone: +86-571-87236579 Fax: +86-571-87068731
Received: May 25, 2004
Revised: May 26, 2004
Accepted: June 24, 2004
Published online: June 21, 2005
Abstract

AIM: To evaluate the inhibitory effects of DNAzymes on the expressions of hepatitis B virus (HBV) s (HBsAg) and e (HBeAg) in 2.2.15 cells, and to explore the potential therapeutic effects of DNAzymes on replication of HBV genome.

METHODS: DNAzymes DrzBS and DrzBC specific to HBV (ayw subtype) s gene ORF A157UG and e gene ORF A1816UG, were designed and synthesized. Inhibitory effects of DrzBS or DrzBC on the expressions of HBV s and e genes as well as HBV DNA levels in culture supernatants were observed in 2.2.15 cells.

RESULTS: After being treated with DrzBS or DrzBC, the expression of HBV s or e genes in 2.2.15 cells was depressed dramatically. The maximum inhibition rate was 94.2% and 91.8% for DrzBS and DrzBC, respectively. The concentration for effective inhibition of both DrzBS and DrzBC was within 0.1-2.5 µmol/L, showing a dose-dependence. The efficiency of inhibiting HBsAg, HBeAg in 2.2.15 cells by DrzBS or DrzBC was higher than that of the same target genes by antisense oligonucleotides (ASON). The concentration for effective inhibition of DNAzymes was at least 10-fold lower compared with ASON controls. Neither inhibition on the replication of HBV DNA nor toxicity to 2.2.15 cells was observed.

CONCLUSION: DrzBS and DrzBC can block the expression of HBV s- and e-genes in 2.2.15 cells and provide a specific and effective anti-HBV gene therapeutic means.

Keywords: DNAzyme; HBV; Gene expression; Inhibition