Drug Resistance, Viral ; Hepatitis B virus ; drug effects

Background: Nucleic acid testing (NAT) has been widely used for transfusion - transmitted infection screening at blood banks all over the world to reduce window period, yet the assay has not been implemented in Vietnam. Objective: Using and evaluating cost - effectiveness of NAT in screening HIV, HCV, HBV in blood \r\n', u'donors. Subjects and methods: The study was carried out on 9392 blood donors at National Institute of Hematology and Blood Transfusion from Jan to May 2007 who were HIV, HCV, HBV negative with ELISA. Plasma from donors was pooled (pool size of 8) and tested with UItrio Procleix HIV - 1, HCV, HBV (Chiton). Results: These 9392 plasma samples were pooled into 1174 pool samples to perform NAT. Among 1174 pooled samples, there was only 1 case with negative ELISA - Reactive NAT. The sample was determined as response with probe HCV. From there, one of eight pool samples was identified responding to probe HCV and it was more likely to have been missed in the window period when screened by ELISA.Conclusion: The sample should be further tested with HCV qualitative and quantitative testing to confirm the status of infection. \r\n', u'\r\n', u'
HIV ; Hepatitis B virus/drug effects ; Hepacivirus ; Blood Donors

Antiviral Agents ; pharmacology ; Hepatitis B virus ; drug effects ; Interferons ; pharmacology

Drug Resistance, Viral ; Endopeptidases ; Hepatitis B virus ; drug effects ; Hepatitis B, Chronic ; virology ; Humans ; Interferons ; pharmacology

Antiviral Agents ; pharmacology ; Dideoxyadenosine ; analogs & derivatives ; pharmacology ; Hepatitis B virus ; drug effects ; Virus Replication ; drug effects

Drug Resistance, Viral ; Hepatitis B virus ; drug effects ; Hepatitis B, Chronic ; drug therapy ; virology ; Humans ; Nucleosides ; pharmacology

Hepatitis B virus ; drug effects ; physiology ; Hodgkin Disease ; drug therapy ; Humans ; Immunoconjugates ; therapeutic use ; Virus Activation ; drug effects

<b>OBJECTIVEb>To explore the effects of the extract from Phyllanthus urinaria L. on hepatitis B virus (HBV) replication and expression in HBV transient transfection model in vitro.

<b>METHODSb>The eukaryotic expression plasmid pHBV1.1, which contains 1.1-fold-overlength genome of HBV, was transfected into the human hepatoma cell line, HepG2, to establish and assess the HBV transient transfection model. The extract from Phyllanthus urinaria L. was prepared in different concentrations and methyl thiazolyl tetrazolium was used to detect the maximum nontoxic concentration of the drug. The extract from Phyllanthus urinaria L. were added into the transfected cell, at the concentrations of 0.8, 0.2 and 0.05 g/L, respectively. Four days after drug application, enzyme-linked immuno sorbent assay was used to detect the concentration of HBsAg in the supernatants, Southern blot was applied to analyze HBV DNA level, and Western blot was used to detect the expression of HBcAg in cells.

<b>RESULTSb>After the transfection of plasmid pHBV1.1 into HepG2 cells, the concentration of HBsAg in supernatants was increased obviously as compared with that of the normal cells (P<0.05), and all expected HBV replicative intermediates were confirmed by Southern blot analysis, which ensured the successful establishment of the HBV transient transfection model. After the application of drugs at the concentrations of 0.8 and 0.2 g/L, the level of HBsAg was obviously decreased in the supernatants, as compared with that of the virus group (P<0.05); Southern blot showed that the level of HBV rc DNA, ds DNA, ss DNA was obviously reduced compared with that of the virus group (P<0.01); Western blot revealed that the expression of HBcAg in the drug group was obviously inhibited, as compared with that of the virus group (P<0.01).

<b>CONCLUSIONSb>The extract from Phyllanthus urinaria L. obviously inhibited replication and expression of HBV in HBV transfected cell lines in vitro, thus exerting distinctive anti-HBV effects.

Hep G2 Cells ; Hepatitis B ; drug therapy ; Hepatitis B virus ; drug effects ; physiology ; Humans ; Phyllanthus ; Plant Extracts ; pharmacology ; Transfection ; Virus Replication ; drug effects

<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

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