Jun Inoue

Tohoku University, Sendai, Kagoshima-ken, Japan

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Publications (72)185.72 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The viral factors of hepatitis B virus (HBV), such as genotypes and mutations, were reported to affect the development of fulminant hepatitis B (FHB), but the mechanism is still unclear. To investigate HBV mutations associated with FHB, especially in the subgenotype B1/Bj HBV (HBV/B1), which are known to cause FHB frequently in Japan. A total of 96 serum samples from acute self-limited hepatitis B (AHB) patients and 13 samples from FHB patients were used for full-genome/partial sequencing. A total of 107 chronic infection patients with HBV were also examined for the distribution of mutants. In the analysis of full-genome sequences of HBV/B1 (FHB, n=11; non-FHB, n=35) including those from the databases, mutations at nt 1961 [T1961V (not T)] and nt 1962 [C1962D (not C)], which change S21 in the core protein, were found more frequently in FHB than in non-FHB (100% vs. 20%, 55% vs. 3%, respectively). When our FHB and AHB samples were compared, T1961V and C1962D were significantly more frequent in FHB than in AHB, both in the overall analysis (46% vs. 6%, 39% vs. 3%, respectively) and in HBV/B1 (100% vs. 29%, 100% vs. 14%, respectively). A newly developed PCR system detecting T1961V showed that HBV/B1 and low viral load were independent factors for the mutation among chronic infection patients. T1961V/C1962D mutations were found frequently in FHB, especially in HBV/B1. The resulting S21 substitution in the core protein may play important roles in the development of FHB.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 07/2012; 55(2):147-52. · 3.12 Impact Factor
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    ABSTRACT: BACKGROUND: The immunopathogenesis of dual chronic infection with hepatitis B virus and hepatitis C virus (HBV/HCV) remains unclear. The in vivo suppressive effects of each virus on the other have been reported. In this study we aimed to analyze the virological and immunological parameters of HBV/HCV coinfected patients during pegylated interferon/ribavirin (Peg-IFN/RBV) therapy. METHODS: One patient with high HBV-DNA and high HCV-RNA titers (HBV-high/HCV-high) and 5 patients with low HBV-DNA and high HCV-RNA titers (HBV-low/HCV-high) were enrolled. Twenty patients monoinfected with HBV and 10 patients monoinfected with HCV were enrolled as control subjects.. In vitro cultures of Huh 7 cells with HBV/HCV dual infection were used to analyze the direct interaction of HBV/HCV. RESULTS: Direct interaction of HBV clones and HCV could not be detected in the Huh-7 cells. In the HBV-high/HCV-high-patient, the HCV-RNA level gradually declined and HBV-DNA gradually increased during Peg-IFN/RBV therapy. Activated CD4- and CD8-positive T cells were increased at 1 month of Peg-IFN/RBV-therapy, but HBV-specific IFN-γ-secreting cells were not increased and HBV-specific interleukin (IL)-10 secreting cells were increased. The level of HBV- and HCV-specific IFN-γ-secreting cells in the HBV-high/HCV-high-patient was low in comparison to that in the HBV- or HCV-monoinfected patients. In the HBV-low/HCV-high-patient, HCV-RNA and HBV-DNA rapidly declined during Peg-IFN/RBV therapy. Activated CD4- and CD8-positive T cells were increased, and HBV- and HCV-specific IFN-γ-secreting cells were also increased during Peg-IFN/RBV-therapy. CONCLUSION: The immunological responses of the HBV-high/HCV-high patient were low in comparison to the responses in HBV and HCV monoinfected patients. Moreover, the response of immune cells in the HBV-high/HCV-high patient during Peg-IFN/RBV therapy was insufficient to suppress HBV and HCV.
    Journal of Gastroenterology 05/2012; · 3.79 Impact Factor
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    ABSTRACT: Hepatitis C virus (HCV) is a positive-strand enveloped RNA virus that shows diverse viral populations even in one individual. Though Sanger sequencing has been used to determine viral sequences, deep sequencing technologies are much faster and can perform large-scale sequencing. We demonstrate the successful use of Illumina deep sequencing technology and subsequent analyses to determine the genetic variants and amino acid substitutions in both treatment-naïve (patient 1) and treatment-experienced (patient 7) isolates from HCV-infected patients. As a result, almost the full nucleotide sequence of HCV was detectable for patients 1 and 7. The reads were mapped to the HCV reference sequence. The coverage was 99.8% and the average depth was 69.5× for patient 7, with values of 99.4% (coverage) and 51.1× (average depth) for patient 1. In patient 7, amino acid (aa) 70 in the core region showed arginine, with methionine at aa 91, by Sanger sequencing. Major variants showed the same amino acid sequence, but minor variants were detectable in 18% (6/34 sequences) of sequences, with replacement of methionine by leucine at aa 91. In NS3, 8 amino acid positions showed mixed variants (T72T/I, K213K/R, G237G/S, P264P/S/A, S297S/A, A358A/T, S457S/C, and I615I/M) in patient 7. In patient 1, 3 amino acid positions showed mixed variants (L14L/F/V, S61S/A, and I586T/I). In conclusion, deep sequencing technologies are powerful tools for obtaining more profound insight into the dynamics of variants in the HCV quasispecies in human serum.
    Journal of clinical microbiology 12/2011; 50(3):857-66. · 4.16 Impact Factor
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    ABSTRACT: The molecular mechanisms of assembly and budding of hepatitis C virus (HCV) remain poorly understood. The budding of several enveloped viruses requires an endosomal sorting complex required for transport (ESCRT), which is part of the cellular machinery used to form multivesicular bodies (MVBs). Here, we demonstrated that Hrs, an ESCRT-0 component, is critical for the budding of HCV through the exosomal secretion pathway. Hrs depletion caused reduced exosome production, which paralleled with the decrease of HCV replication in the host cell, and that in the culture supernatant. Sucrose-density gradient separation of the culture supernatant of HCV-infected cells revealed the co-existence of HCV core proteins and the exosome marker. Furthermore, both the core protein and an envelope protein of HCV were detected in the intraluminal vesicles of MVBs. These results suggested that HCV secretion from host cells requires Hrs-dependent exosomal pathway in which the viral assembly is also involved.
    Virology 12/2011; 422(2):377-85. · 3.35 Impact Factor
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    ABSTRACT: The genotype B of hepatitis B virus (HBV) was reported to associate with fulminant hepatitis (FH). We aimed to clarify the characteristics of HBV obtained from FH patients in an area of Japan where genotype B HBV is prevalent. Using serum samples of 16 HBV-associated FH patients, partial HBV sequences were determined. The effects of HBV mutation/insertion/deletion were evaluated using an in vitro HBV replication system. Of the 16 HBV isolates, 31% belonged to subgenotype B1/Bj, 38% were subgenotype B2/Ba, and 31% were subgenotype C2/Ce. Notably, the single nucleotide insertion/deletion that resulted in a frameshift of the precore protein was found exclusively in 60% of B1/Bj strains. An in vitro study showed that all of the frameshift mutants had significantly higher amounts of HBV DNA than did the wild type. One of the isolates had a novel insertion of A between nucleotides 1900 and 1901, which resulted in a 3-nucleotide change within the Kozak sequence of the core protein and enhanced the core protein expression in vitro. The frameshift insertion/deletion in the precore region enhanced HBV replication and might be associated with the development of FH by the subgenotype B1/Bj HBV.
    The Journal of Infectious Diseases 10/2011; 204(7):1017-25. · 5.85 Impact Factor
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    ABSTRACT: Aim:  The extracellular hepatitis C virus (HCV)-antigen, including HCV-Core protein, can suppress immune cells. Recently, the efficacy of double filtration plasmapheresis (DFPP) for chronic hepatitis C (CHC) was reported. However, the mechanism of efficacy of DFPP might not be only the reduction of HCV but also the effect of immune cells via direct and/or indirect mechanisms. The aim of this study is to analyze the virological and immunological parameters of difficult-to-treat HCV patients treated with DFPP combined with Peg-interferon and RBV (DFPP/Peg-IFN/RBV) therapy. Methods:  Twelve CHC patients were enrolled and treated with DFPP/Peg-IFN/RBV therapy. The immunological, virological and genetic parameters were studied. Results:  All patients (4/4) treated with the major IL28B allele (T/T) could achieve complete early virological response (EVR). The amounts of HCV-Core antigen in the peripheral blood of EVR patients treated with DFPP/Peg-IFN/RBV rapidly declined in comparison to those of late virological response (LVR) patients treated with DFPP/Peg-IFN/RBV and EVR patients treated with Peg-IFN and RBV (Peg-IFN/RBV). The amount of IFN-γ produced from peripheral blood gradually increased. On the other hand, the amount of IL10 gradually decreased in the EVR patients. The frequencies of HCV-Core binding on CD3+ T cells rapidly declined in EVR patients treated with DFPP/Peg-IFN/RBV therapy. Moreover, the distributions of activated CD4(+) and CD8(+) T cells and CD16-CD56 high natural killer cells were significantly changed between before and after DFPP. Conclusions:  The rapid reduction of HCV-Core antigens and changes in the distribution of lymphoid cells could contribute to the favorable immunological response during DFPP/Peg-IFN/RBV therapy.
    Hepatology Research 09/2011; 41(12):1153-68. · 2.07 Impact Factor
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    ABSTRACT: Lymphotropic hepatitis C virus (HCV) infection of B and T cells might play an important role in the pathogenesis of hepatitis C. Recently, we showed that a lymphotropic HCV (SB strain) could infect established T-cell lines and B-cell lines. However, whether HCV replication interferes with cell proliferation and function in primary T lymphocytes is still unclear. The aim of this study was to analyze whether HCV replication in primary T lymphocytes affected their development, proliferation, and Th1 commitment. SB strain cell culture supernatant (2 × 10(4) copies/ml HCV) was used to infect several kinds of primary lymphocyte subsets. Mock, UV-irradiated SB-HCV, JFH-1 strain, and JFH-1 NS5B mutant, which could not replicate in T cells, were included as negative controls. Carboxyfluorescein succinimidyl ester (CFSE) and CD45RA double staining was used to evaluate the proliferative activity of CD4(+)CD45RA(+)CD45RO(-) naïve CD4(+) cells. Interferon (IFN)-γ and interleukin (IL)-10 secretion assays magnetic cell sorting (MACS) were carried out. Negative strand HCV RNA was detected in CD4(+), CD14(+), and CD19(+) cells. Among CD4(+) cells, CD4(+)CD45RA(+)RO(-) cells (naïve CD4(+) cells) were most susceptible to replication of the SB strain. The levels of CFSE and CD45RA expression gradually declined during cell division in uninfected cells, while HCV-infected naïve CD4(+) cells expressed higher levels of CFSE and CD45RA than Mock or UV-SB infected naïve CD4(+) cells. Moreover, the production of IFN-γ was significantly suppressed in SB-infected naïve CD4(+) cells. Lymphotropic HCV replication suppressed proliferation and development, including that towards Th1 commitment, in human primary naïve CD4(+) cells.
    Journal of Gastroenterology 02/2011; 46(2):232-41. · 3.79 Impact Factor
  • The Indian Journal of Medical Research 01/2011; 133:11-3. · 2.06 Impact Factor
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    ABSTRACT: Organ allocation in Japan remains difficult due to the shortage of deceased-donor livers. The screening tool for controlling nutritional status (CONUT) has been considered to be an established assessment model for evaluating nutritional aspects in surgical patients. However, the application of this CONUT for evaluating the prognosis of patients with end-stage liver diseases has not been evaluated. We assessed the predictability of the prognoses of 58 patients with end-stage liver disease using various prognostic models. The patients registered at the transplantation center of Tohoku University Hospital for the waiting list of Japan Organ Transplant Network for liver transplantation were retrospectively analyzed. The prognoses of the patients were evaluated using the following 5 models: CONUT, the model for ELD with incorporation of sodium (MELD-Na), Child-Turcotte-Pugh score (CTP), prognostic nutritional indices (Onodera: PNI-O), and the Japan Medical Urgency criteria of the liver (JMU). Cox's proportional hazard model, log-rank test and concordance(c)-static were used for the statistics. The indices were 17.74 ± 5.80 for MELD-Na, 9.21 ± 2.19 for CTP, 33.92 ± 11.16 for PNI-O, and 7.57 ± 3.09 for CONUT. Univariate analysis revealed the significance of CONUT (p = 0.017, Odds: 1.325) but not MELD-Na, CTP, JMU or PNI-O for prediction. The cumulative survival rate was clearly discriminated at CONUT point 7. The c-static was 0.081 for the 6-month (M) survival rate, 0.172 for 12M, 0.517 for 36M, 0.821 for 48M, and 0.938 for 60M for CONUT. In conclusion, CONUT shows best predictability for the distant prognoses of patients with ELD.
    The Tohoku Journal of Experimental Medicine 01/2011; 224(3):215-9. · 1.37 Impact Factor
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    ABSTRACT: The innate immune cells can not normally respond to the pathogen in patients with decompensated cirrhosis. Previous studies reported that antigen-presenting cells take up L-Cystine (L-Cys) and secrete substantial amounts of L-Glutamate (L-Glu) via the transport system Xc- (4F2hc+xCT), and that this exchange influences the immune responses. The aim of this study is to investigate the influence of the plasma L-Cys/L-Glu imbalance observed in patients with advanced cirrhosis on the function of circulating monocytes. We used a serum-free culture medium consistent with the average concentrations of plasma amino acids from patients with advanced cirrhosis (ACM), and examined the function of CD14+ monocytes or THP-1 under ACM that contained 0-300 nmol/mL L-Cys with LPS. In patients with advanced cirrhosis, we actually determined the TNF-alpha and xCT mRNA of monocytes, and evaluated the correlation between the plasma L-Cys/L-Glu ratio and TNF-alpha. The addition of L-Cys significantly increased the production of TNF alpha from monocytes under ACM. Monocytes with LPS and THP-1 expressed xCT and a high level of extracellular L-Cys enhanced L-Cys/L-Glu antiport, and the intracellular GSH/GSSG ratio was decreased. The L-Cys transport was inhibited by excess L-Glu. In patients with advanced cirrhosis (n = 19), the TNF-alpha and xCT mRNA of monocytes were increased according to the Child-Pugh grade. The TNF-alpha mRNA of monocytes was significantly higher in the high L-Cys/L-Glu ratio group than in the low ratio group, and the plasma TNF-alpha was significantly correlated with the L-Cys/L-Glu ratio. A plasma L-Cys/L-Glu imbalance, which appears in patients with advanced cirrhosis, increased the TNF-alpha from circulating monocytes via increasing the intracellular oxidative stress. These results may reflect the immune abnormality that appears in patients with decompensated cirrhosis.
    PLoS ONE 01/2011; 6(8):e23402. · 3.73 Impact Factor
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    ABSTRACT: Accumulating evidence suggests that cancer stem cells (CSC) play an important role in tumorigenicity. Epithelial cell adhesion molecule (EpCAM) is one of the markers that identifies tumor cells with high tumorigenicity. The expression of EpCAM in liver progenitor cells prompted us to investigate whether CSC could be identified in hepatocellular carcinoma (HCC) cell lines. The sorted EpCAM(+) subpopulation from HCC cell lines showed a greater colony formation rate than the sorted EpCAM(-) subpopulation from the same cell lines, although cell proliferation was comparable between the two subpopulations. The in vivo evaluation of tumorigenicity, using supra-immunodeficient NOD/scid/γc(null) (NOG) mice, revealed that a smaller number of EpCAM(+) cells (minimum 100) than EpCAM(-) cells was necessary for tumor formation. The bifurcated differentiation of EpCAM(+) cell clones into both EpCAM(+) and EpCAM(-) cells was obvious both in vitro and in vivo, but EpCAM(-) clones sustained their phenotype. These clonal analyses suggested that EpCAM(+) cells may contain a multipotent cell population. Interestingly, the introduction of exogenous EpCAM into EpCAM(+) clones, but not into EpCAM(-) clones, markedly enhanced their tumor-forming ability, even though both transfectants expressed a similar level of EpCAM. Therefore, the difference in the tumor-forming ability between EpCAM(+) and EpCAM(-) cells is probably due to the intrinsic biological differences between them. Collectively, our results suggest that the EpCAM(+) population is biologically quite different from the EpCAM(-) population in HCC cell lines, and preferentially contains a highly tumorigenic cell population with the characteristics of CSC.
    Cancer Science 10/2010; 101(10):2145-55. · 3.48 Impact Factor
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    ABSTRACT: Exosomes are nanovesicles derived from multivesicular bodies (MVBs) in antigen-presenting cells. The components of the ESCRT (endosomal sorting complex required for transport) pathway are critical for the formation of MVBs, however the relationship between the ESCRT pathway and the secretion of exosomes remains unclear. We here demonstrate that Hrs, an ESCRT-0 protein, is required for fascilitating the secretion of exosomes in dendritic cells (DCs). Ultrastructural analyses showed typical saucer-shaped exosomes in the culture supernatant from both the control and Hrs-depleted DCs. However, the amount of exosome secretion was significantly decreased in Hrs-depleted DCs following stimulations with ovalbumin (OVA) as well as calcium ionophore. Antigen-presentation activity was also suppressed in exsosomes purified from Hrs-depleted DCs, while no alteration in OVA degradation was seen in Hrs-depleted DCs. These data indicated that Hrs is involved in the regulation of antigen-presentation activity through the exosome secretion.
    Biochemical and Biophysical Research Communications 08/2010; 399(3):384-90. · 2.41 Impact Factor
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    ABSTRACT: HBcAg-specific regulatory T (T(reg)) cells play an important role in the pathogenesis of chronic hepatitis B. Soluble heat shock proteins, especially soluble heat shock protein 60 (sHSP60), could affect the function of T(reg) cells via Toll-like receptor. We analyzed the relationship between soluble heat shock protein production and hepatitis B virus (HBV) replication with both clinical samples from HBeAg-positive patients with chronic hepatitis B (n= 24) and HBeAb-positive patients with chronic hepatitis B (n= 24) and in vitro HBV-replicating hepatocytes. Thereafter, we examined the biological effects of sHSP60 with isolated T(reg) cells. The serum levels of sHSP60 in patients with chronic hepatitis B were statistically significantly higher than those in patients with chronic hepatitis C (P<.01), and the levels of sHSP60 were correlated with the HBV DNA levels (r = 0.532; P<.001) but not with the alanine aminotransferase levels. Moreover, the levels of sHSP60 in HBV-replicating HepG2 cells were statistically significantly higher than those in control HepG2 cells. Preincubation of CD4(+) CD25(+) cells with recombinant HSP60 (1 ng/mL) statistically significantly increased the frequency of HBcAg-specific interleukin 10-secreting T(reg) cells. The frequency of IL7R(-)CD4(+)CD25(+) cells, the expression of Toll-like receptor 2, and the suppressive function of T(reg) cells had declined during entecavir treatment. The function of HBcAg-specific T(reg) cells was enhanced by sHSP60 produced from HBV-infected hepatocytes. Entecavir treatment suppressed the frequency and function of T(reg) cells; this might contribute to the persistence of HBV infection.
    The Journal of Infectious Diseases 07/2010; 202(2):202-13. · 5.85 Impact Factor
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    ABSTRACT: Although chronic infection of hepatitis B virus (HBV) is currently managed with nucleot(s)ide analogues or interferon-alpha, the control of HBV infection still remains a clinical challenge. Peroxisome proliferator-activated receptor (PPAR) is a ligand-activated transcription factor, that plays a role in glucose and lipid metabolism, immune reactions, and inflammation. In this study, the suppressive effect of PPAR ligands on HBV replication was examined in vitro using a PPARalpha ligand, bezafibrate, and a PPARgamma ligand, rosiglitazone. The effects were examined in HepG2 cells transfected with a plasmid containing 1.3-fold HBV genome. Whereas bezafibrate showed no effect against HBV replication, rosiglitazone reduced the amount of HBV DNA, hepatitis B surface antigen, and hepatitis B e antigen in the culture supernatant. Southern blot analysis showed that the replicative intermediates of HBV in the cells were also inhibited. It was confirmed that GW9662, an antagonist of PPARgamma, reduced the suppressive effect of rosiglitazone on HBV. Moreover, rosiglitazone showed a synergistic effect on HBV replication with lamivudine or interferon-alpha-2b. In conclusion, this study showed that rosiglitazone inhibited the replication of HBV in vitro, and suggested that the combination therapy of rosiglitazone and nucleot(s)ide analogues or interferon could be a therapeutic option for chronic HBV infection.
    Biochemical and Biophysical Research Communications 05/2010; 396(2):508-14. · 2.41 Impact Factor
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    ABSTRACT: Excessive trans-fatty acids (TFA) consumption has been thought to be a risk factor mainly for coronary artery diseases while less attention has been paid to liver disease. We aimed to clarify the impact of TFA-rich oil consumption on the hepatic pathophysiology compared to natural oil. Mice were fed either a low-fat (LF) or high-fat (HF) diet made of either natural oil as control (LF-C or HF-C) or partially hydrogenated oil, TFA-rich oil (LF-T or HF-T) for 24 weeks. We evaluated the liver and body weight, serological features, liver lipid content and composition, liver histology and hepatic lipid metabolism-related gene expression profile. In addition, primary cultures of mice Kupffer cells (KCs) were evaluated for cytokine secretion and phagocytotic ability after incubation in cis- or trans-fatty acid-containing medium. The HF-T-fed mice showed significant increases of the liver and body weights, plasma alanine-aminotransferase, free fatty acid and hepatic triglyceride content compared to the HF-C group, whereas the LF-T group did not differ from the LF-C group. HF-T-fed mice developed severe steatosis, along with increased lipogenic gene expression and hepatic TFA accumulation. KCs showed increased tumor necrosis factor secretion and attenuated phagocytotic ability in the TFA-containing medium compared to its cis-isomer. Excessive consumption of the TFA-rich oil up-regulated the lipogenic gene expression along with marked hepatic lipid accumulation. TFA might be pathogenic through causing severe steatosis and modulating the function of KCs. The quantity and composition of dietary lipids could be responsible for the pathogenesis of non-alcoholic steatohepatitis.
    Journal of Hepatology 04/2010; 53(2):326-34. · 9.86 Impact Factor
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    ABSTRACT: To investigate the efficacy of long-term lamivudine (3TC) and adefovir dipivoxil (ADV) combination therapy in 3TC-resistant chronic hepatitis B virus (HBV) infected patients, we analysed 28 3TC-resistant patients treated with the combination therapy during 47 months (range, 9-75). At 12, 24, 36, and 48 months, the rates of virological response with undetectable HBV DNA (≤ 2.6 log copies/mL) were 56, 80, 86, and 92%, respectively. Among 17 hepatitis B e antigen (HBeAg)-positive patients, HBeAg disappeared in 24% at 12 months, 25% at 24 months, 62% at 36 months, and 88% at 48 months. When HBV genotypes were compared, patients with genotype B achieved virological response significantly more rapidly than those with genotype C (P=0.0496). One patient developed virological breakthrough after 54 months, and sequence analysis of HBV obtained from the patient was performed. An rtA200V mutation was present in the majority of HBV clones, in addition to the 3TC-resistant mutations of rtL180M+M204V. The rtN236T ADV-resistant mutation was observed in only 25% clones. In vitro analysis showed that the rtA200V mutation recovered the impaired replication capacity of the clone with the rtL180M+M204V mutations and induced resistance to ADV. Moreover, rtT184S and rtS202C, which are known entecavir-resistant mutations, emerged in some rtL180M+M204V clones without rtA200V or rtN236T. In conclusion, 3TC+ADV combination therapy was effective for most 3TC-resistant patients, especially with genotype B HBV, but the risk of emergence of multiple drug-resistant strains with long-term therapy should be considered. The mutation rtA200V with rtL180M+M204V may be sufficient for failure of 3TC+ADV therapy.
    Journal of Viral Hepatitis 03/2010; 18(3):206-15. · 3.08 Impact Factor
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    ABSTRACT: The peribiliary inflammation of cholangiopathy affects the physiological properties of biliary epithelial cells (cholangiocyte), including bicarbonate-rich ductular secretion. We revealed the upregulation of annexin A2 (ANXA2) in cholangiocytes in primary biliary cirrhosis (PBC) by a proteomics approach and evaluated its physiological significance. Global protein expression profiles of a normal human cholangiocyte line (H69) in response to interferon-gamma (IFNgamma) were obtained by two-dimensional electrophoresis followed by MALDI-TOF-MS. Histological expression patterns of the identified molecules in PBC liver were confirmed by immunostaining. H69 cells stably transfected with doxycyclin-inducible ANXA2 were subjected to physiological evaluation. Recovery of the intracellular pH after acute alkalinization was measured consecutively by a pH indicator with a specific inhibitor of anion exchanger (AE), 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS). Protein kinase-C (PKC) activation was measured by PepTag Assay and immunoblotting. Twenty spots that included ANXA2 were identified as IFNgamma-responsive molecules. Cholangiocytes of PBC liver were decorated by the unique membranous overexpression of ANXA2. Apical ANXA2 of small ducts of PBC was directly correlated with the clinical cholestatic markers and transaminases. Controlled induction of ANXA2 resulted in significant increase of the DIDS-inhibitory fraction of AE activity of H69, which was accompanied by modulation of PKC activity. We, therefore, identified ANXA2 as an IFNgamma-inducible gene in cholangiocytes that could serve as a potential histological marker of inflammatory cholangiopathy, including PBC. We conclude that inducible ANXA2 expression in cholangiocytes may play a compensatory role for the impaired AE activity of cholangiocytes in PBC in terms of bicarbonate-rich ductular secretion and bile formation through modulation of the PKC activity.
    Laboratory Investigation 10/2009; 89(12):1374-86. · 3.96 Impact Factor
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    ABSTRACT: A plasmid carrying 1.3-fold HBV genome was constructed from a HBV strain that caused five consecutive cases of fulminant hepatitis (pBFH2), and HepG2 cells were transfected with pBFH2 or its variants. The pBFH2 construct with A1762T/G1764A, G1862T, and G1896A showed the largest amount of core particle-associated intracellular HBV DNA, but no significant increase of extracellular HBV DNA in comparison with the wild construct, suggesting that these mutations might work together for retention of the replicative intermediates in the cells. The retention might relate to the localization of hepatitis B core antigen (HBcAg) in the nucleus of HepG2, which was observed by confocal fluorescence microscopy. HBcAg immunohistochemical examination of liver tissue samples obtained from the consecutive fulminant hepatitis patients showed stronger staining in the nucleus than acute hepatitis patients. In conclusion, the fulminant HBV strain caused retention of the core particles and the core particle-associated HBV DNA in the cells.
    Virology 10/2009; 395(2):202-9. · 3.35 Impact Factor
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    ABSTRACT: Hepatitis E virus (HEV) is one of the causative agents of acute or fulminant hepatitis. Viral factors may play a role in the pathogenesis of fulminant hepatitis E. We aimed to investigate the nucleotide substitutions of the HEV genome affecting the severity of hepatitis E. The comparison of 28 reported full-length nucleotide sequences of genotype 4 HEV showed that the substitution of C at nucleotide 5907 (C5907) was most closely associated with fulminant hepatitis (fulminant hepatitis, 100%; acute hepatitis, 39.1%; p = 0.0204). Analyzing the full-length sequences of 28 genotype-4 and 11 genotype-3 HEV retrievable from DNA databases and 35 partial sequences recovered from patients with acute or fulminant hepatitis, we show that the presence of both U3148 and C5907 is associated with fulminant hepatitis in patients with HEV of genotype 4 (p = 0.0042) and genotype 3 or 4 (p = 0.0009), and that the prothrombin activity is significantly lower in patients infected with HEV carrying U3148 and C5907 than in those without the substitutions (p = 0.0069). U3148 and C5907 are silent substitutions that do not change amino acid. However, since U3148 is located at the RNA helicase domain and C5907 is located within the capsid gene, the secondary structure of the HEV RNA genome carrying U3148 and C5907 may be favorable for translation of the viral proteins. C5907 was associated with high HEV load (> or = 10(5) copies/ml) at initial examination (p = 0.0427). We propose that U3148 and C5907 are associated with the severity of hepatitis E.
    The Tohoku Journal of Experimental Medicine 08/2009; 218(4):279-84. · 1.37 Impact Factor
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    ABSTRACT: An imbalance of plasma amino acids is observed in patients with advanced cirrhosis. The aim of this study was to investigate the influence of the extracellular amino acid imbalance on the function of myeloid dendritic cells (DCs) in patients with advanced cirrhosis. We made a serum-free culture medium consistent with the average concentration of plasma amino acids from healthy controls (HC, n = 25) or patients with advanced cirrhosis (LC, n = 43) to reflect more closely the actual environment of the living body. We compared the phenotypical and biological functions of blood dendritic cells antigen-positive dendritic cells (BDCA+ DCs) and monocyte-derived dendritic cells (MoDCs) from LC and HC with these media. After adding stimulants, the CD83 and CD86 expressions of DCs from LC were lower than those from HC. In both HC and LC, both CD83 and CD86 expressions of DCs stimulated under the cirrhotic medium were lower than under the control medium. This phenomenon was accompanied by a suppression of the mammalian target of rapamycin (mTOR)/S6K-signaling pathways. The interleukin 12 (IL-12) production in the cirrhotic medium was significantly lower than in the control medium and increased when valine or leucine was added to the medium. In patients with advanced cirrhosis, peripheral blood mononuclear cells stimulated in the autologous plasma after oral administration of branched-chain amino acid (BCAA) granules had significantly increased interferon gamma production. CONCLUSION: In advanced cirrhosis, there is impairment of the function and maturation of DCs, which has been shown to be related to an imbalance in the extracellular amino acid profile. Elevating the extracellular concentration of BCAAs ex vivo in patients with advanced cirrhosis improved the function of DCs.
    Hepatology 08/2009; 50(6):1936-45. · 12.00 Impact Factor

Publication Stats

615 Citations
185.72 Total Impact Points

Institutions

  • 2006–2011
    • Tohoku University
      • • Department of Gastroenterology
      • • Division of Internal Medicine
      Sendai, Kagoshima-ken, Japan
  • 2006–2008
    • Jichi Medical University
      • Division of Virology
      Totigi, Tochigi, Japan
  • 2005
    • Iwaki Kyoritsu General Hospital
      Ивакуни, Yamaguchi, Japan
  • 1995
    • Keio University
      • Department of Internal Medicine
      Tokyo, Tokyo-to, Japan
  • 1966–1972
    • The Jikei University School of Medicine
      • Department of Internal Medicine
      Edo, Tōkyō, Japan