Drug Resistance, Viral ; genetics ; Hepatitis B virus ; drug effects ; genetics ; Mutation

Drug Resistance, Viral ; genetics ; Hepatitis B virus ; drug effects ; genetics ; Mutation ; Nucleosides ; pharmacology

<b>OBJECTIVEb>To observe the inhibitory effect of a eukaryotic expression vector expressing human IFN-gamma (pcDNA3.1- IFN-gamma) on HBV replication in hepG2.2.15 cells.

<b>METHODSb>The eukaryotic expression vector expressing human IFN-gamma was constructed using PCR and gene recombination technique. hepG2.2.15 cells were transfected with pcDNA3.1-IFN-gamma and the culture supernatant was collected to determine the expression of IFN-gamma protein by ELISA. The HBV DNA copies and the concentration of HBeAg and HBsAg were measured by fluorescence real-time PCR and ELISA kit, respectively.

<b>RESULTSb>Compared with that of negative control and blank 2.2.15 cells, the concentration of HBeAg in the supernatant of 2.2.15 cells transfected with pcDNA3.1- IFN-gamma were decreased by 49%, and HBsAg concentration was lowered by 35% and 33%, respectively. A significant decrease of HBV DNA copies was observed in pcDNA3.1- IFN-gamma-transfected cells in comparison with the two control cells. No significant differences were noted in all the results between the two control groups.

<b>CONCLUSIONb>We have successfully constructed the eukaryotic expression vector expressing human IFN-gamma, which provides a basis for anti-HBV gene therapy using human IFN-gamma.

Genetic Vectors ; Hep G2 Cells ; Hepatitis B virus ; drug effects ; Humans ; Interferon-gamma ; genetics ; pharmacology ; Transfection ; Virus Replication ; drug effects

<b>OBJECTIVEb>To observe the distribution of HBV variants resistant to lamivudine and their relation to clinical manifestations of chronic hepatitis.

<b>METHODSb>Using direct sequencing, YMDD (tyrosine-methionine-aspartate-aspartate) variants in patients with chronic HBV were detected before and during treatment with lamivudine. A statistical analysis of the distribution of HBV strains resistant to lamivudine was performed.

<b>RESULTb>Four variant strains existed in patients before lamivudine treatment, 128 variant resistant strains were noted after 6 mouths of lamivudine treatment including 42 YVDD (valine) variants, 20 YIDD (isoleusine) variants and 66 non-YMDD variants. According to the hepatitis severity, 8 patients were mild, 108 moderate and 12 severe. Viral loading was higher and clinical types were more severe in no-YMDD variants.

<b>CONCLUSIONb>Variant strains including strains resistant to lamivudine exist naturally before lamivudine treatment, but lamivudine-resistant ones become more dominant after treatment. Liver inflammation is more severe in non-YMDD group.

Antiviral Agents ; pharmacology ; Drug Resistance, Viral ; Genetic Variation ; Hepatitis B virus ; drug effects ; genetics ; Lamivudine ; pharmacology

Replication of the hepatitis B virus is suppressed by deficiency of the X protein. Although several molecules that block cellular targets of X protein reduce the production of hepatitis B virus progeny, the effect of a specific inhibitor of X protein on viral replication has not been investigated. To block X protein specifically, we adopted an intracellular expression approach using H7 single chain variable fragment (H7scFv), an antibody fragment against X protein. We previously demonstrated that cytoplasmic expression of H7scFv inhibits X protein-induced tumorigenicity and transactivation. In this study, intracellular H7scFv expression inhibits reporter gene transactivation but not viral replication determined by endogenous hepatitis B virus polymerase activity assay and real-time PCR. Our findings imply that intracellular expression of antibody fragment against X protein may not be an alternative therapeutic modality for inhibition of hepatitis B virus replication.
Virus Replication/*drug effects ; Trans-Activators/*antagonists & inhibitors/immunology ; Immunoglobulin Variable Region/genetics/metabolism/*pharmacology ; Hepatitis B virus/*drug effects/physiology ; Hepatitis B e Antigens/metabolism ; Cell Line

<b>OBJECTIVEb>To investigate the influence of SEN virus infection on their response to lamivudine in patients with chronic hepatitis B (CHB).

<b>METHODSb>SEN virus-D and -H DNA were detected in 45 CHB patients who received lamivudine 12 months with nested-PCR, and YMDD motif mutations in HBV DNA were investigated with gene chip.

<b>RESULTSb>The positive rate of SEN virus DNA was 11.1% (5/45), and there were four out of the five SEN virus DNA positive patients whose HBV DNA was positive, among them, two patients existed YMDD motif mutation. While ten out of the forty SEN virus DNA negative patients appeared HBV DNA positive. The response rate was significant lower in SEN virus-infected patients than that in uninfected patients (chi 2=3.97, P<0.05).

<b>CONCLUSIONb>Coinfection with SEN virus in chronic hepatitis B patients may adversely affect the outcome of treatment with lamivudine

Anti-HIV Agents ; pharmacology ; DNA, Viral ; analysis ; drug effects ; Hepatitis B virus ; drug effects ; genetics ; Hepatitis B, Chronic ; complications ; virology ; Humans ; Lamivudine ; pharmacology ; Respirovirus Infections ; complications ; Sendai virus

Betulinic acid is a naturally occurring pentacyclic triterpenoid, which has antiretroviral, antimalarial, and anti-inflammatory properties. The purpose of this study is to investigate the HBV DNA replication inhibition in the mouse model with betulinic acid. Hydrodynamic injection method via the tail vein with the Paywl. 3 plasmid was used to establish the animal mode (n = 15), and the mice were randomly divided into the PBS control group (n = 5), Betulinic acid treatment group (n = 5) and lamivudine control group (n = 5). The day after successful modeling , the mice would have taken Betulinic acid (100 mg x kg(-1)), lamivudine (50 mg x kg(-1)), PBS drugs orally, once daily for 7 days, blood samples were acquired from the orbital venous blood at 3, 5, 7 days after the administering, HBsAg and HBeAg in serum concentration were measured by ELISA and the mice were sacrificed after 7 days, HBV DNA southern detections were used with part of mice livers. The results showed that betulinic acid significantly inhibited the expression of HbsAg in the mice model at the fifth day compared with the control group, and there was no significant differences between the effects of lamivudine and the PBS control group; both the betulinic acid and lamivudine groups had no significant inhibition for the HBeAg expression; the HBV DNA expressions of the liver tissue from the betulinic acid and lamivudine groups were inhibited compared with the control group. Taken together, these results reveal betulinic acid can inhibit the HBsAg expression and replication of the liver HBV DNA in the mouse model.
Acute Disease ; Animals ; Antiviral Agents ; pharmacology ; DNA Replication ; drug effects ; DNA, Viral ; biosynthesis ; Hepatitis B ; blood ; virology ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; drug effects ; genetics ; immunology ; physiology ; Male ; Mice ; Plasmids ; genetics ; Triterpenes ; pharmacology ; Virus Replication ; drug effects

Adult ; Drug Resistance, Viral ; genetics ; Female ; Genotype ; Guanine ; analogs & derivatives ; pharmacology ; therapeutic use ; Hepatitis B virus ; drug effects ; genetics ; Hepatitis B, Chronic ; drug therapy ; genetics ; Humans

<b>OBJECTIVEb>To investigate the evolution of hepatitis B virus (HBV) quasispecies in one patient during lamivudine (LAM) monotherapy and switching to entecavir (ETV) rescue treatment.

<b>METHODSb>Serum samples were taken at seven different time points during antiviral therapy (0, 24, 48, 60, 72, 96, 152 weeks, respectively), the HBV DNA polymerase gene was amplified, cloned and sequenced to analyze the amino acid substitutions within HBV DNA polymerase gene and distribution of virus quasispecies. Quantitative detection of the HBV wild strains and total virus was performed by amplification refractory mutation system real-time PCR (ARMS-PCR).

<b>RESULTSb>Three mutation patterns detected during antiviral therapy in the patient: rtM204V, rtM204V+rtL180M and rtM204I. The HBV quasispecies were found always in dynamic variation. The HBV populations were completely replaced with the LAM-resistant variants when the viral breakthrough was encountered during LAM monotherapy. Interestingly, the wild-type variants presented gradually dominant (79.3%) with the decline of HBV DNA load after switching to ETV rescue administration. ARMS-PCR results showed that the wild-type variants account ed for 68.55% of the HBV populations at baseline and this proportion declined to 0.21% when the viral breakthrough emerged under LAM therapy. The wild-type variants gradually increased from week 24 after switching to ETV rescue therapy and the proportion of HBV wild-type variants in the population fluctuated between 16.01% to 26.93%.

<b>CONCLUSIONSb>The distribution of virus quasispecies were always in dynamic variation during sequential therapy with nucleotide analogs in chronic hepatitis B patients. Different patterns of dynamic HBV quasispecies may have different contribution in ETV resistance in LMV refractory patients with ETV administration.

Adult ; Antiviral Agents ; therapeutic use ; DNA, Viral ; genetics ; Drug Resistance, Viral ; genetics ; Genotype ; Hepatitis B virus ; drug effects ; genetics ; Hepatitis B, Chronic ; drug therapy ; virology ; Humans ; Male ; Mutation

DNA, Viral ; genetics ; Hep G2 Cells ; Hepatitis B virus ; drug effects ; Humans ; Oligonucleotides, Antisense ; pharmacology