Characterization of a Specific Region in the Hepatitis B Virus Enhancer I for the Efficient Expression of X Gene in the Hepatic Cell

AbstractHepatitis B virus (HBV) enhancer I has been shown to consist of severalcis-acting sequences for the HBV gene expression efficiently in certain types of cells. Transcriptional regulation of HBV X gene mediated by enhancer I might be one of the mechanisms by which HBV obtains hepatotropism. By mutagenesis analysis of enhancer I function in the enhancer I/X gene promoter complex, we characterized a specific transcriptional regulatory region (designated as a LSR element, nt 989–1030) of enhancer I for the X gene promoter by means of the transient transfection technique using hepatic and nonhepatic cells. Based on the analysis of protein factors interacting with the LSR element, liver-enriched transcriptional factors, HNF3 and HNF4 or retinoid X receptor α (RXRα), are probably implicated in the activity of enhancer I for the efficient expression of X gene through their interaction with the LSR element in the hepatic cell. Furthermore, the isolated LSR element was demonstrated to function alone as a specificcis-acting element and to be able to activate transcription from the X gene promoter efficiently in the hepatic cell in an orientation-independent manner

Evaluation of monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) for antigen detection of foot-and-mouth disease virus using clinical samples.

A monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) method was previously developed for foot-and-mouth disease (FMD) viral antigen detection. Here we evaluated the sensitivity and specificity of two FMD viral antigen detection MSD-ELISAs and compared them with conventional indirect sandwich (IS)-ELISA. The MSD-ELISAs were able to detect the antigen in saliva samples of experimentally-infected pigs for a longer term compared to the IS-ELISA. We also used 178 RT-PCR-positive field samples from cattle and pigs affected by the 2010 type-O FMD outbreak in Japan, and we found that the sensitivities of both MSD-ELISAs were about 7 times higher than that of the IS-ELISA against each sample (P<0.01). In terms of the FMD-positive farm detection rate, the sensitivities of the MSD-ELISAs were about 6 times higher than that of the IS-ELISA against each farm (P<0.01). Although it is necessary to conduct further validation study using the other virus strains, MSD-ELISAs could be appropriate as a method to replace IS-ELISA for FMD antigen detection

Human Amnion-Derived Mesenchymal Stem Cell Transplantation Ameliorates Liver Fibrosis in Rats

Background: Mesenchymal stem cells (MSCs) are a valuable cell source in regenerative medicine. Recently, several studies have shown that MSCs can be easily isolated from human amnion. In this study, we investigated the therapeutic effect of transplantation of human amnion-derived MSCs (hAMSCs) in rats with liver fibrosis. Methods: Liver fibrosis was induced by an intraperitoneal injection of 2 mL/kg of 50% carbon tetrachloride twice a week for 6 weeks. At 3 weeks, hAMSCs (1 × 10^6 cells) were transplanted intravenously. Rats were sacrificed at 7 weeks, and histological analyses and quantitative reverse-transcription polymerase chain reaction were performed. In vitro experiments were conducted to investigate the effect of hAMSCs on the activation of Kupffer cells. Results: Transplantation of hAMSCs significantly reduced the fibrotic area, deposition of type-I collagen, the number of α-smooth muscle actin-positive hepatic stellate cells, and CD68-positive Kupffer cells in the livers. messenger RNA expression of α-smooth muscle actin and tissue inhibitor of metalloproteinase-1 was significantly decreased and the expression of matrix metalloproteinase-9 and hepatocyte growth factor was significantly increased in the liver of hAMSC-treated rats. Transplantation of hAMSCs at 3 weeks plus 5 weeks did not have an additive effect. In vitro experiments demonstrated that Kupffer cell activation induced by lipopolysaccharide was significantly decreased by culturing with conditioned medium obtained from hAMSCs. Conclusions: Transplantation of hAMSCs provided significant improvement in a rat model of liver fibrosis, possibly through the inhibition of Kupffer cell and hepatic stellate cell activation. hAMSCs may be a potential new treatment for liver fibrosis

Comparison of the results of FMDV antigen detection methods using saliva of FMDV-inoculated pigs.

<p>*MS: MSD-ELISA for multi-serotypes; SS: MSD-ELISA for single serotypes (O, A, Asia1); IS: Indirect sandwich-ELISA for each serotype (O, A, Asia1); rPCR: real-time RT-PCR.</p>†<p>The OD results (average sample OD-average buffer OD) of the MS, SS and IS ELISAs were as +++, >1.0; ++, 0.5–1.0; +, 0.1–0.5; and −, <0.1.</p>‡<p>The results-related plaque-forming unit of rPCR were as +++,>10⁴; ++, 10²–10³; +, 10⁰–10²; and −, <10⁰.</p>§<p>The pigs inoculated with virus were euthanized.</p>∥<p>Squares mean the day the obvious vesicular appeared except for the inoculated site.</p

Sensitivities of the MSD-ELISAs and the IS-ELISA against the FMDV-positive field samples by RT-PCR.

<p>*A total of 178 RT-PCR-positive samples (135 oral swab samples, 7 nasal samples, 24 oral and nasal swab samples, 12 samples of 10% emulsion of homogenized epithelial tissue) collected in the 2010 type O FMD outbreak in Japan from 78 farms were used.</p>†<p>In both the MSD-ELISAs and the IS-ELISA, OD results ( =  sample OD − average negative OD) of 0.1 or more were judged as positive.</p>‡<p>Fractions in parentheses show ELISA-positive samples or farms/RT-PCR-positive samples or farms.</p>§<p>The amounts of two samples were insufficient for the test.</p>∥<p>The sensitivities against farm units were calculated using the sensitivities against samples.</p

Pegylated interferon-alfa-2a monotherapy in patients infected with HCV genotype 2 and importance of rapid virological response

Abstract Background Pegylated (PEG)-interferon (IFN)-alfa-2a plus ribavirin (RBV) therapy for 24 weeks is now a standard treatment protocol for patients with hepatitis C virus (HCV) genotype 2. As RBV cannot be used in certain situations, we examined whether PEG-IFN-alfa-2a monotherapy for 24 weeks or less would be sufficient to obtain a sustained virological response (SVR) in patients infected with HCV genotype 2. Methods Forty-nine consecutive patients with HCV genotype 2 received PEG-IFN-alfa-2a (180 μg/week) subcutaneously without oral RBV for 8-64 weeks. HCV RNA level was determined by COBAS AMPLICOR HCV Test, v2.0. Results HCV RNA was equal to or less than 100 KIU/mL (defined as low viral load) in 15 of 49 patients, and the remaining 34 had HCV RNA above 100 KIU/mL (defined as high viral load). All 15 patients with low viral load achieved rapid virological response (RVR; HCV RNA negative at week 4), and also achieved SVR with an average treatment duration of 17.1 weeks. The 34 patients with high viral load were treated for 33.7 weeks on average, and 19 of them (55.9%) achieved RVR. The SVR rates of these patients were significantly higher in those with RVR than without RVR (16/19 vs. 6/15 p = 0.0074). Conclusion PEG-IFN-alfa-2a monotherapy for 24 weeks or less might be sufficient to treat selected patients with HCV genotype 2, especially those with low viral load and becoming negative for HCV RNA by week 4 of treatment.</p