RESUMEN
<p><b>BACKGROUND</b>To determine the feasibility of inhibition of duck hepatitis B virus (DHBV) DNA replication by antisense phosphorothioate oligodeoxynucleotides corresponding to DHBV transcription region.</p><p><b>METHODS</b>The authors designed three antisense phosphorothioate oligodeoxynucleotides which correspond to DHBV PreS1,PreS2 and S antigen gene promotors respectively. The DNA replication level was detected with Southern blot method and cpm calculation.</p><p><b>RESULTS</b>Primary duck hepatocyte culture was treated with 1.5 micromol/L antisense oligodeoxynucleotides in vitro, all the antisense fragments caused a firm inhibition of viral DNA replication and the inhibition rates were 61.5%, 69.3% and 62.4%, respectively. In vivo, the animals were treated with 10 microgram/g PreS1 antigen gene promotor antisense oligodeoxynucleotides per day for 6 days and a very strong inhibition rate of 87.9% was obtained.</p><p><b>CONCLUSIONS</b>The results demonstrated the potential clinical application of antisense phosphorothioate oligodeoxynucleotides in clinics.</p>