OBJECTIVE: To observe the changes of replication and antigen expressions of lamivudine-resistant hepatitis B virus (HBV) with polymerase gene mutation. METHODS: With site-directed mutagenesis, we constructed 3 HBV plasmids with polymerase gene mutation based on the template P3.8II. All the plasmids were transfected into HepG2 cells, in which the replication and expression of the virus were analyzed. RESULTS: The 3 polymerase gene mutant HBVs were successfully constructed. HBsAg and HBeAg expressions were detected in the supernatants of HepG2 cells transfected with these plasmids. The replication of the 3 mutant plasmids with rtG172E, rtG174C and rtG172E/rtG174C mutation decreased significantly in comparison with the wild-type virus. CONCLUSION: The 3 polymerase gene mutant HBVs shows depressed capacity for viral replication, and in vitro drug sensitivity study is needed to establish the relationship between these mutations and nucleoside analogue resistance.
OBJECTIVE: To observe the changes of replication and antigen expressions of lamivudine-resistant hepatitis B virus (HBV) with polymerase gene mutation. METHODS: With site-directed mutagenesis, we constructed 3 HBV plasmids with polymerase gene mutation based on the template P3.8II. All the plasmids were transfected into HepG2 cells, in which the replication and expression of the virus were analyzed. RESULTS: The 3 polymerase gene mutant HBVs were successfully constructed. HBsAg and HBeAg expressions were detected in the supernatants of HepG2 cells transfected with these plasmids. The replication of the 3 mutant plasmids with rtG172E, rtG174C and rtG172E/rtG174C mutation decreased significantly in comparison with the wild-type virus. CONCLUSION: The 3 polymerase gene mutant HBVs shows depressed capacity for viral replication, and in vitro drug sensitivity study is needed to establish the relationship between these mutations and nucleoside analogue resistance.