Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this paper, 43 drugs have been screened and evaluated for their ability of anti-hepatitis B virus by way of detecting in the cell culture medium the HBsAG and HBeAG secreted from the 2.2.15 cell line--a cell line derived from the Hep-G2 transfected with cloned HBV DNA. In addition, the MTT colorimetric assay is used in the process for monitoring the cytotoxic effects. The result showed that five drugs, including anti-HBV-I, anti-HBV-II, Radix Astragali Co., Rhizoma Curculiginis Co. and 518BII-A-6 are promising anti-HBV drugs.
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PMID:[A research for screening anti-hepatitis B virus drugs with the 2.2.15 cell line]. 133 8

A human hepatoblastoma cell line was stably transfected with a head-to-tail dimer of the Hepatitis B virus (HBV), subtype adw, genome to generate a cell line which produces HBV. FIAU [1-(2'-deoxy-2'-fluoro-1-beta-D-arabinofuranosyl-5-iodo)uracil] inhibited viral replication in these cells with an IC50 of 0.90 microM, as determined by PCR analysis of extracellular Dane particle DNA, and displayed a 50% cytotoxic concentration (TC50) of 344.3 microM, as determined using the MTT assay. The selectivity index of FIAU (TC50/IC50) was 382.6. In cells incubated for 10 days with FIAU (100 microM) and then incubated with drug-free media with daily media changes for 7 days, viral DNA replication was markedly inhibited but resumed within 24 h after drug removal, demonstrating that the in vitro anti-HBV activity of FIAU is reversible. Both the antiviral activity and cytotoxicity of FIAU were reversed by the addition of equimolar to 10-fold excess molar concentrations of thymidine. The de-iodinated metabolite of FIAU, FAU, had only marginal anti-HBV activity at 100 microM, indicating that this metabolite does not contribute significantly to the activity of FIAU. The examination of intracellular viral DNA replicative intermediates revealed that FIAU was 2000-fold more active against duck HBV DNA replication in human hepatoma cells (IC50 = 0.075 microM) than against this same virus in chicken liver cells (IC50 = 156 microM). FIAU was anabolized to a 25-fold greater extent in human hepatoma cells than in chicken cells, indicating that the anti-HBV activity of this nucleoside analog is dependent, in part, on its phosphorylation by the host cell.
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PMID:The in vitro anti-hepatitis B virus activity of FIAU [1-(2'-deoxy-2'-fluoro-1-beta-D-arabinofuranosyl-5-iodo)uracil] is selective, reversible, and determined, at least in part, by the host cell. 814 92

In this study, we adopted several methods of MTT colorimetry, DAPI fluorimetry and ELISA to study the effects of extremely low frequency (ELF) capacitively coupled electric fields (EFs) on the metabolism of 6B1 cells. The result shows that 50 mV cm(-1) ELF EF (10-100 Hz) has no significant effect on proliferation, DNA synthesis and activity of succinate dehydrogenase of 6B1 cells, indicating that the effect of ELF (10-100 Hz) EF on the metabolism of 6B1 cells is not obvious. However, 50 mV cm(-1), 50 Hz EF significantly promotes the HBs-Ab (Hepatitis B surface antibody) secretion of 6B1 cells, implying that under this situation, EF has some distinctive effect on the outerface of 6B1 cell membrane.
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PMID:Effects of ELF capacitively coupled weak electric fields on metabolism of 6B1 cells. 1037 56

AIM:To develop a safe and effective DNA vaccine for inducing humoral and cellular immunological responses against hepatitis B virus surface antigen (HBsAg).METHODS:BALB/c mice were inoculated with NV-HB/s, a recombinant plasmid that had been inserted S gene of hepatitis B virus genome and could express HBsAg in eukaryotes. HBsAg expression was measured by ABC immunohis tochemical assay, generation of anti-HBs by ELISA and cytotoxic T lymphocyte (CTL), by MTT method, existence of vaccine DNA by Southern blot hybridization and activation of oncogene C-myc by in situ hybridization.RESULTS:With NV-HB/s vaccination by intramuscular injection, anti-HBs was initially positive 2 weeks after inoculation while all mice tested were HBsAg positive in the muscles.The titers and seroconversion rate of anti-HBs were steadily increasing as time went on and were dose dependent. All the mice inoculated with 100&mgr;g NV-HB/s were anti-HBs positive one month after inoculation, the titer was 1 1024 or more. The humoral immune response was similar induced by either intramuscular or intradermal injection. CTL activities were much stronger (45.26%) in NV-HB/s DNA immunized mice as compared with those (only 6%) in plasma-derived HBsAg vaccine immunized mice. Two months after inoculation, all muscle samples were positive by Southernblot hybridization for NV-HB/s DNA detection, but decreased to 25% and all were undetectable by in situ hybridiza-tion after 6 months.No oncogene C-myc activation was found in the muscle of inoculation site.CONCLUSION:NV-HB/s could generate humoral and cellular immunolo-gical responses against HBsAg that had been safely expressed in situ by NV-HB/s vaccination.
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PMID:DNA-based vaccination induces humoral and cellular immune responses against hepatitis B virus surface antigen in mice without activation of C-myc. 1181 65

Hepatitis B virus x gene product (HBx) is known to be a transactivator of transcriptional elements that regulate the expression of a variety of genes associated with the growth, differentiation, survival and the apoptosis of cells. However, the exact mechanism of the activation and inhibition of cellular events by HBx remains uncertain. The present study was designed to measure the effect of HBx, on the signal transduction pathways associated with intracellular Ca(2+) mobilization following HBx transfection in the stable Chang liver cells (CHL-X). Enhanced cell proliferation by HBx in CHL-X was confirmed by MTT assay and by the immunodetection of PCNA. The transactivation of AP-1 by HBx induced in CHL-X was inhibited by cyclosporin A (CsA), a mitochondrial Ca(2+) channel blocker and by BAPTA-AM, a cytosolic Ca(2+) blocker. Activation of the SAPK/JNK signaling pathway by HBx was evidenced by the increased phosphorylations of c-Jun (Ser63) and of JNK (Thr183/Tyr185). Increased phospho-Erk/Erk and phospho-Raf1/Raf in HBx-induced CHL-X indicated that HBx might stimulate the MAPK pathway. PI3K activity and cytosolic free Ca(2+) levels were elevated in HBx-induced CHL-X. These results imply that HBx transactivates both JNK and MAPK signal transduction pathways in association with the mobilization of cytosolic Ca(2+).
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PMID:Activation of calcium signaling by hepatitis B virus-X protein in liver cells. 1450 71

Fifty-six different Chinese medicinal herbs from 29 families were evaluated for their antiviral activities against duck hepatitis B virus (DHBV) in vitro. The DHBV DNA level in primary duck hepatocyte cultures was monitored by dot blot hybridization and the cytotoxicity was evaluated by MTT assay. Anti-DHBV activities were found more strongly in the aqueous extracts of Ardisia chinensis and Pithecellobium clypearia with selective indices of 2.6 and >2.7, respectively, which were comparable to that of 2',3'-dideoxycytidine. Further research on the isolation of the active antiviral phytochemicals from these herbs may provide alternative options for the treatment of chronic hepatitis B.
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PMID:In vitro antiviral activities of Chinese medicinal herbs against duck hepatitis B virus. 1689 61

Natural killer (NK) cells and cytolytic T lymphocytes (CTL) have been implicated as important effectors of antiviral defense. We previously isolated a novel antibacterial polypeptide, which was identified as high mobility group nucleosomal-binding domain 2 (HMGN2), from human mononuclear leukocytes. This study examined the antiviral activity of HMGN2 against human hepatitis virus B. HMGN2 was isolated and purified from the acid soluble proteins of the human THP-1 cell line, and identified by mass spectrum, Western blot and antibacterial assay. The hepatitis B virus (HBV)-transfected HepG2.2.15 cell line was used in the in vitro assay system. In the range of 1-100 microg/ml HMGN2, no cytotoxicity for HepG2.2.15 cells was detected by MTT assay. When incubated with HMGN2 at 1-100 microg/ml for 72 or 144 h, there was a significant reduction in hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) expression, which were detected by ELISA, and a significant reduction in HBV DNA copies, which was determined by the real time quantitative PCR, in the supernatant of HepG2.2.15 cells. Northern and Southern blot analysis also showed that the levels of the HBV 3.5 kb and the 2.4/2.1 kb mRNA species and HBV replicative intermediate DNA were significantly reduced in the HMGN2-treated HepG2.2.15 cells. These results indicated that HMGN2 protein could markedly inhibit HBV protein expression and replication in vitro.
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PMID:Inhibitory effect of HMGN2 protein on human hepatitis B virus expression and replication in the HepG2.2.15 cell line. 1915 Mar 74

The pyrimidine thione derivatives 2a-d were prepared by the reaction of thiourea, ethyl cyanoacetate and several aromatic aldehydes. The acyclic thioglycosides 4a-7d were prepared by the reaction of the synthesized pyrimidine thiones 2a-d with different alkyl halides, whereas the reaction of 2a-d with 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide afforded the cyclic thioglycosides 8a-d whose deprotection afforded 9a-d. The obtained compounds were tested for their antischistosomal and antiviral activity against hepatitis B virus (HBV). Compounds 5a, 5d, 7a showed high activity against HBV using the MTT assay; moreover compounds 5c, 6d, 7a, 9a, 9c exhibited high activity as antischistosomal agents.
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PMID:Antiviral and antischistosomal evaluation of newly synthesized thioglycosides and their acyclic analogues. 1979 97

This study investigated the inhibitory capacity of oxymatrine on in vitro hepatitis B virus (HBV) replication. HepG2.2.15 cells were treated with oxymatrine 50, 100, 200, 400, 800 or 1000 mg/l, or with human interferon-alpha2b (IFN-alpha2b 1000 U/l) as a positive control. Levels of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and HBV-DNA in cell supernatants were determined by enzyme-linked immunosorbent assay and fluorescent quantitative-polymerase chain reaction, respectively. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometric analysis and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labelling were used to evaluate the cytotoxicity of oxymatrine. The inhibitory effects of oxymatrine gradually increased as the concentration increased from 200 to 1000 mg/l for HBsAg and HBeAg, and from 200 to 400 mg/l for HBV-DNA. There was no inhibitory effect of oxymatrine at concentrations < 200 mg/l. No significant difference was seen between human IFN-alpha2b (positive control) and oxymatrine >or= 200 mg/l. It is concluded that oxymatrine can inhibit in vitro HBV replication and antigen expression at concentrations >or= 200 mg/l.
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PMID:Inhibition of the replication of hepatitis B virus in vitro by oxymatrine. 1993 Aug 45

Chronic hepatitis B virus infection is associated with a high risk of developing into hepatocellular carcinoma, while tumor recognition is important during the immune surveillance process that prevents cancer development in humans. The mechanisms of immune evasion and the role of the early immune response in chronic infection caused by hepatitis B virus (HBV) are still unclear. In the present study, 1 copy or 1.2 copies of HBV genome was transfected into a hepatocellular carcinoma cell line BEL7405. RT-PCR, Western blot and flow cytometry analysis were used to evaluate the expression of HLA class I molecules and transporter associated with antigen processing 1 (TAP1). Finally, the cytotoxic activity of natural killer (NK) cells against HBV transfected liver cells was detected by MTT colorimetry method. Following transfection of 1 copy or 1.2 copies of HBV genome, HLA class I expression was up-regulated in BEL7405 cell line in a dose-dependent manner. Furthermore, increased the surface HLA class I expression were caused by enhanced expression of TAP1 at mRNA and protein levels in those transfected cells. Consequently, a significantly down-regulated cytotoxic activity of NK cells against HBV transfected liver cells was observed. These results may demonstrate a way by which HBV avoids recognition by NK cells that might be associated with the establishment of chronic infection and tumor formation.
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PMID:Up-regulate HLA class I expression following hepatitis B virus transfection in a hepatocellular carcinoma cell line BEL7405. 2065 29


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