• Title, Summary, Keyword: HCV

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Development of Trans-Splicing Aptazyme Which Can Specifically Modify Hepatitis C Virus Genome (C형 간염바이러스(HCV) 유전체를 특이적으로 변형할 수 있는 Trans-Splicing Aptazyme 발굴)

  • Kim, Ju-Hyun;Lee, Chang-Ho;Jang, Sun-Young;Lee, Seong-Wook
    • Korean Journal of Microbiology
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    • v.44 no.3
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    • pp.186-192
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    • 2008
  • For the development of specific and effective basic genetic materials to inhibit replication of hepatitis C virus (HCV), HCV genome-targeting trans-splicing aptazyme, which activity is allosterically regulated by a specific ligand, was developed. The aptazyme was designed to be comprised of sequence of RNA aptamer to the ligand, communication module sequence which can transfer structural transition for inducing ribozyme activity upon binding the ligand to the aptamer, and trans-splicing ribozyme targeting +199 nt of HCV IRES. Especially, when the aptamer and the communication module was inserted at both P6 and P8 catalytic domain of the specific ribozyme, allosteric activity of the aptazyme was the most induced. The aptazyme was shown to induce activity of trans-splicing reaction specifically and efficiently only in the presence of the specific ligand, but neither in the absence of any ligand nor in the presence of control ligand. This aptazyme can be used as a specific and effective genetic agent against HCV, and a tool for the isolation of anti-HCV lead compounds.

Establishment of Plasma Working Standards for the Performance and Quality Assurance of NAT Screening Tests for HIV, HCV and HBV (HIV, HCV와 HBV 유전자 분석시약의 성능 및 품질관리용 Plasma Working Standards 제조에 관한 연구)

  • Kim, Myung Han;Cho, Youn Jung;Kwon, So-Yong;Cho, Nam Sun
    • The Korean Journal of Blood Transfusion
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    • v.23 no.2
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    • pp.152-161
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    • 2012
  • Background: Since Jan. 2012, for performance evaluation of viral reagents, analysis of domestic samples has been recommended in order to obtain approval from the KFDA when they are first introduced to Korea. This regulation requires the standard domestic materials driven from locally infected samples. We tried manufacturing the plasma working standards of HBV, HCV, and HIV NAT using a mixed titer of viral loads. Methods: Forty three HBV DNA positive plasmas, 25 HCV RNA positive plasmas, and 26 HIV RNA positive plasmas were evaluated according to viral load and genotype. Several plasma units, which had high-titer viral loads and the common viral genotypes in Korea, were selected as the source materials for each viral standard. To adjust the appropriate concentration based on the detectable range of variable viral reagents, the source plasma was diluted to several concentrations, divided into small vials, and analyzed for quantification. Results: The 13 plasma working standards, which had variable viral loads for the mixed titer performance panel of HIV, HCV, and HBV NAT, were produced. Conclusion: These national standard materials were first produced in order to supply the mixed titer performance panel for the viral NAT reagent of the level IV transfusion related high-risk group in Korea.

Cooperative stimulation of cisplatin-mediated apoptosis by hepatitis B virus X Protein and hepatitis C virus core Protein (B형 간염 바이러스 X 단백질과 C형 간염 바이러스의 코어 단백질에 의한 cisplatin-매개성 세포 예정사의 협조적 촉진)

  • Kwun, Hyun-Jin;Jang, Kyung-Lib
    • Journal of Life Science
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    • v.17 no.6
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    • pp.766-771
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    • 2007
  • The co-infection with hepatitis B virus (HBV) and hepatitis C Virus (HCV) is associated with a more severe liver disease and increased frequency in the development of hepatocellular carcinoma com-pared to those with single infection. Here, we demonstrated that HBV X protein (HBx) and HCV Core cooperatively up-regulated the level of p53 in human hepatoma HepG2 cells. The elevated p53 subsequently stimulated the expression of proapoptotic Bax whereas it repressed the expression of antiapoptotic Bcl2. These effects, however, were not observed in p53-negative Hep3B cells. Consistently to their cooperative regulation of apoptotic effectors, HBx and HCV Core additively stimulated cisplatin-mediated apoptotic cell death of HepG2 but not of Hep3B cells. These results may help to explain the development of a more severe liver disease in patients co-infection with HBV and HCV as well as some contradictory results on the roles of HBx and Core in apoptosis.

Purification and Characterization of HCV RNA-dependent RNA Polymerase from Korean Genotype 1b Isolate: Implications for Discovery of HCV Polymerase Inhibitors

  • Kim, Jeong-Min;Lee, Mi-Kyoung;Kim, Yong-Zu
    • Bulletin of the Korean Chemical Society
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    • v.26 no.2
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    • pp.285-291
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    • 2005
  • The nonstructural protein 5B (NS5B) of hepatitis C virus (HCV) is the viral RNA-dependent RNA polymerase (RdRp), which is the essential catalytic enzyme for the viral replication and is an appealing target for the development of new therapeutic agents against HCV infection. A small amount of serum from a single patient with hepatitis C was used to get the genome of a Korean HCV isolate. Sequence analysis of NS5B 1701 nucleotides showed the genotype of a Korean isolate to be subtype 1b. The soluble recombinant HCV NS5B polymerase lacking the C-terminal 24 amino acids was expressed and purified to homogeneity. With the highly purified NS5B protein, we established in vitro systems for RdRp activity to identify potential polymerase inhibitors. The rhodanine family compounds were found to be potent and specific inhibitors of NS5B from high throughput screening (HTS) assay utilizing the scintillation proximity assay (SPA) system. The binding mode of an inhibitor was analyzed by measuring various kinetic parameters. Lineweaver-Burk plots of the inhibitor suggested it binds not to the active site of NS5B polymerase, but to an allosteric site of the enzyme. The activity of NS5B in in vitro polymerase reactions with homopolymeric RNA requires interaction with multiple substrates that include a template/primer and ribonucleotide triphosphate. Steady-state kinetic parameter, such as Km, was determined for the ribonucleotide triphosphate. One of compounds found interacts directly with the viral polymerase and inhibits RNA synthesis in a manner noncompetitively with respect to UTP. Furthermore, we also investigated the ability of the compound to inhibit NS5B-directed viral RNA replication using the Huh7 cell-based HCV replicon system. The investigation is potentially very useful for the utility of such compounds as anti-hepatitic agents.

Hepatitis B and C Seroprevalence in Solid Tumors - Necessity for Screening During Chemotherapy

  • Oguz, Arzu;Aykas, Fatma;Unal, Dilek;Karahan, Samet;Uslu, Emine;Basak, Mustafa;Karaman, Ahmet
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1411-1414
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    • 2014
  • Background: Hepatitis B and C are the leading causes of liver diseases worldwide. For hematological and solid malignancy patients undergoing chemotherapy, increases in HBV DNA and HCV RNA levels can be detected which may result in reactivation and hepatitis-related morbidity and mortality. The aim of this study was to determine the seroprevalence of Hbs ag and Anti HCV positivity in patients with solid malignancies undergoing chemotherapy and consequences during follow-up. Materials and Methods: The files of 914 patients with solid malignancies whose hepatitis markers were determined serologically at diagnosis were reviewed retrospectively. All underwent adjuvant/palliative chemotherapy. For the cases with HBV and/or HCV positivity, HBV DNA and HCV RNA levels, liver function tests at diagnosis and during follow-up and the treatment modalities that were chosen were determined. Results: Of 914 cases, Hbs Ag, anti Hbs and anti HCV positivity were detected in 40 (4.4%), 336 (36.8%) and 26 (2.8%) of the cases respectively. All of the Hbs ag positive patients received prophylactic lamuvidine before the start of chemotherapy. In the Hbs ag and anti HCV positive cases, liver failure was not detected during chemotherapy and a delay in chemotherapy courses because of hepatitis was not encountered. Conclusions: Just as with hematological malignancies, screening for HBV and HCV should also be considered for patients with solid tumors undergoing chemotherapy. Prophylactic antiviral therapy for HBV reduces both the reactivation rates and HBV related mortality and morbidity. The clinical impact of HCV infection on patients undergoing chemotherapy is still not well characterized.

Comparison of Viral Hepatitis-Associated Hepatocellular Carcinoma Due to HBV and HCV - Cohort from Liver Clinics in Pakistan

  • Munaf, Alvina;Memon, Muhammad Sadik;Kumar, Prem;Ahmed, Sultan;Kumar, Maheshwari Bhunesh
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7563-7567
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    • 2014
  • Background: Hepatocellular carcinoma (HCC) is the first cause of death in cirrhotic patients, mostly due to viral hepatitis with HCV or HBV infection. This study was performed to estimate the true prevalence of viral hepatitis-related HCC and the demographic and clinical-pathological associations with the two virus types. Materials and Methods: This cross sectional observational study enrolled clinical data base of 188 HCC patients and variables included from baseline were age, sex, area of residence, clinical-pathological features such as underlying co-morbidity, presence or absence of liver cirrhosis, macrovascular involvement, tumor extension and metastasis, liver lobes involved, serum alpha-fetoprotein level, and hepatitis serologies. Results: Overall prevalence of HCV- and HBV-related HCC was 66.0% and 34.0%, respectively. Patients with HCV were more likely to develop HCC at advanced age ($52.4{\pm}11.9$ vs. $40.7{\pm}12.09$ years), with highly raised serum AFP levels (${\geq}400ng/ml$) 78.2% (HBV 67.1%), large tumor size (HCV-66% >5 cm, HBV-59.3%), and presence of portal vein thrombosis (8.06%, HBV 1.56%). A binominal multivariate analysis showed that HCV-HCC group were more likely to be cirrhotic (OR=0.245, 95%CI: 0.117, 0.516) and had more than two times higher rate of solitary macrovascular involvement (OR=2.533, 95%CI: 1.162, 5.521) as compared with HBV associated HCC. Conclusions: Statistically significant variations were observed from baseline to clinical-pathological characteristics in HCV vs HBV associated HCC. Our study suggests prompt and early screening for high risk patients so that the rate of progression of these chronic viral diseases to cirrhosis and cancer can be decreased.

Alcohol Induced Hepatic Degeneration of HCV-Tg Mouse

  • Noh, Dong-hyung;Yu, Dae-yeul;Jeong, Kyu-shik
    • Proceedings of the Korean Society of Veterinary Pathology Conference
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    • pp.18-18
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    • 2003
  • Hepatitis C virus (HCV) has become a major public health issue and is prevalent in most countries. HCV infection starts frequently without clinical symptoms, and progresses in the majority of patients (70 to 85%) to persistent viremia and chronic hepatitis including cirrhosis and hepatocellularcarcinoma (HCC) [1]. Alcohol is one of the independent cofactors accelerating the development of HCC in chronic hepatitis C patients. This is of great interest because a synergy between excessive alcohol intake and HCV infection has been documented in the development of HCC in chronic hepatitis C patients [2]. The aim of this study is to investigate liver changes in ethanol feeding HCV-transgenic (Tg) mouse and to establish an animal model system. (omitted)

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2'-Spirocyclopropyl-carbocyclic Nucleoside as a Novel Scaffold for Potent Anti-HCV Agents

  • Li, Hua;Yoo, Jin-Cheol;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • v.32 no.4
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    • pp.1146-1152
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    • 2011
  • The discovery of 2'-spirocyclopropyl-ribocytidine (J. Med. Chem. 2010, 53, 8150-8160) as a potent inhibitor of RNA synthesis by NS5B ($IC_{50}=7.3{\mu}M$), the RNA polymerase encoded by hepatitis C Virus (HCV), has led to the synthesis and biological evaluation of several carbocyclic versions of 2'-spiropropyl-nucleosides. The cyclopentenol intermediate 7 was successfully constructed via ring-closing metathesis (RCM) from divinyl 6. Spirocyclopropanation of enone 8 was effected by using (2-chloroethyl)-dimethylsulfonium iodide and potassium tert-butoxide to form the desired intermediate 9. The synthesized nucleoside analogues 21-24 were assayed for their ability to inhibit HCV RNA replication in a subgenomic replicon Huh7 cell line. Among them, the cytosine nucleoside analogue 22 exhibited significant anti-HCV activity ($EC_{50}= 8.2{\mu}M$).

T-Cell Dysfunction and Inhibitory Receptors in Hepatitis C Virus Infection

  • Lee, Jino;Suh, William I.;Shin, Eui-Cheol
    • IMMUNE NETWORK
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    • v.10 no.4
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    • pp.120-125
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    • 2010
  • Dysfunction of the virus-specific T cells is a cardinal feature in chronic persistent viral infections such as one caused by hepatitis C virus (HCV). In chronic HCV infection, virus-specific dysfunctional CD8 T cells often overexpress various inhibitory receptors. Programmed cell death 1 (PD-1) was the first among these inhibitory receptors that were identified to be overexpressed in functionally impaired T cells. The roles of other inhibitory receptors such as cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and T cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3) have also been demonstrated in T-cell dysfunctions that occur in chronic HCV patients. Blocking these inhibitory receptors in vitro restores the functions of HCV-specific CD8 T cells and allows enhanced proliferation, cytolytic activity and cytokine production. Therefore, the blockade of the inhibitory receptors is considered as a novel strategy for the treatment of chronic HCV infection.

Serotyping in Patients with Chronic Hepatitis C

  • Soon-Mo Chang
    • Biomedical Science Letters
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    • v.9 no.4
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    • pp.209-214
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    • 2003
  • To determine the clinical usefulness of Immuno Blot test, 160 samples from the patients with chronic HCV infection were analyzed. And serotyping and line probe assay were performed to evaluate the distribution of hepatitis C virus genotypes in Korean isolates. In this group, as a result of genotyping type 1 band 2a, the serotype I and II were the most common source of HCV infection. There were no significant difference in response to the alpha-interferon HCV infection treatment with the subtype 1 b or 2a. And the serotypes of NS4 peptides were compared with the genotypes to evaluate their clinical usefulness. Among 49 cases studied for genotypes and serotype, genotype 1 b, 1 b/2b, 2a, 2a/2c and 2b were 51.0%, 2.0%, 34.6%, 8.1% and 4.0%, respectively. The serotypes I and II were 57.1% and 42.8%, respectively; they were matched with genotypes in 85.7% and seemed to be easy to perform. To monitor their performing progress or treatment response, serotype test was made before the genotype test. The Result showed that there was no significant difference in response to the alpha-interferon HCV infection treatment with the subtype 1 b or 2a in Korea.

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