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Sample records for hcv ns3 protease

  1. Antiviral phytochemicals identification from Azadirachta indica leaves against HCV NS3 protease: an in silico approach.

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    Ashfaq, Usman Ali; Jalil, Asma; Ul Qamar, Muhammad Tahir

    2016-08-01

    Hepatitis C virus (HCV) is a major health problem across the world affecting the people of all age groups. It is the main cause of hepatitis and at chronic stage causes liver cirrhosis and hepatocellular carcinoma. Various therapeutics are made against HCV but still there is a need to find out potential therapeutics to combat the virus. The goal of this study is to identify the phytochemicals of Azadirachta indica leaves having antiviral activity against HCV NS3 protease through molecular docking and simulation approach. Results show that the compound 3-Deacetyl-3-cinnamoyl-azadirachtin possesses good binding properties with HCV NS3/4A protease. It can be concluded from this study that Deacetyl-3-cinnamoyl-azadirachtin may serve as a potential inhibitor against NS3/4A protease.

  2. Potent inhibitors of HCV-NS3 protease derived from boronic acids

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    Venkatraman, Srikanth; Wu, Wanli; Prongay, Andrew; Girijavallabhan, Viyyoor; Njoroge, F. George; (SPRI)

    2009-07-23

    Chronic hepatitis C infection is the leading causes for cirrhosis of the liver and hepatocellular carcinoma, leading to liver failure and liver transplantation. The etiological agent, HCV virus produces a single positive strand of RNA that is processed with the help of serine protease NS3 to produce mature virus. Inhibition of NS3 protease can be potentially used to develop effective drugs for HCV infections. Numerous efforts are now underway to develop potent inhibitors of HCV protease that contain ketoamides as serine traps. Herein we report the synthesis of a series of potent inhibitors that contain a boronic acid as a serine trap. The activity of these compounds were optimized to 200 pM. X-ray structure of compound 17 bound to NS3 protease is also discussed.

  3. Differential efficacy of protease inhibitors against HCV genotypes 2a, 3a, 5a, and 6a NS3/4A protease recombinant viruses

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    Gottwein, Judith M; Scheel, Troels K H; Jensen, Tanja B

    2011-01-01

    The hepatitis C virus (HCV) genotype influences efficacy of interferon (IFN)-based therapy. HCV protease inhibitors are being licensed for treatment of genotype 1 infection. Because there are limited or no data on efficacy against HCV genotypes 2-7, we aimed at developing recombinant infectious c...... cell culture systems expressing genotype-specific nonstructural (NS) protein 3 protease (NS3P)....

  4. Engineered toxins "zymoxins" are activated by the HCV NS3 protease by removal of an inhibitory protein domain.

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    Assaf Shapira

    Full Text Available The synthesis of inactive enzyme precursors, also known as "zymogens," serves as a mechanism for regulating the execution of selected catalytic activities in a desirable time and/or site. Zymogens are usually activated by proteolytic cleavage. Many viruses encode proteases that execute key proteolytic steps of the viral life cycle. Here, we describe a proof of concept for a therapeutic approach to fighting viral infections through eradication of virally infected cells exclusively, thus limiting virus production and spread. Using the hepatitis C virus (HCV as a model, we designed two HCV NS3 protease-activated "zymogenized" chimeric toxins (which we denote "zymoxins". In these recombinant constructs, the bacterial and plant toxins diphtheria toxin A (DTA and Ricin A chain (RTA, respectively, were fused to rationally designed inhibitor peptides/domains via an HCV NS3 protease-cleavable linker. The above toxins were then fused to the binding and translocation domains of Pseudomonas exotoxin A in order to enable translocation into the mammalian cells cytoplasm. We show that these toxins exhibit NS3 cleavage dependent increase in enzymatic activity upon NS3 protease cleavage in vitro. Moreover, a higher level of cytotoxicity was observed when zymoxins were applied to NS3 expressing cells or to HCV infected cells, demonstrating a potential therapeutic window. The increase in toxin activity correlated with NS3 protease activity in the treated cells, thus the therapeutic window was larger in cells expressing recombinant NS3 than in HCV infected cells. This suggests that the "zymoxin" approach may be most appropriate for application to life-threatening acute infections where much higher levels of the activating protease would be expected.

  5. Structure-based drug design of novel peptidomimetic cellulose derivatives as HCV-NS3 protease inhibitors.

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    Saleh, Noha A; Elshemey, Wael M

    2017-10-15

    Hepatitis C Virus (HCV) represents a global health threat not only due to the large number of reported worldwide HCV infections, but also due to the absence of a reliable vaccine for its prevention. HCV NS3 protease is one of the most important targets for drug design aiming at the deactivation of HCV. In the present work, molecular docking simulations are carried out for suggested novel NS3 protease inhibitors applied to the Egyptian genotype 4. These inhibitors are modifications of dimer cellulose by adding a hexa-peptide to the cellulose at one of the positions 2, 3, 6, 2', 3' or 6'. Results show that the inhibitor compound with the hexa-peptide at position 6 shows significantly higher simulation docking score with HCV NS3 protease active site. This is supported by low total energy value of docking system, formation of two H-bonds with HCV NS3 protease active site residues, high binding affinity and increased stability in the interaction system. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Molecular screening of phytochemicals from Amelanchier Alnifolia against HCV NS3 protease/helicase using computational docking techniques.

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    Khan, Mahim; Masoud, Muhammad Shareef; Qasim, Muhammad; Khan, Muhammad Asaf; Zubair, Muhammad; Idrees, Sobia; Ashraf, Asma; Ashfaq, Usman Ali

    2013-01-01

    Hepatitis C is serious health concern worldwide caused by HCV. It causes liver cirrhosis and hepato-cellular carcinoma. Development of prevention solutions is under progress. Meanwhile, the treatment of the viral disease using compounds isolated from natural medicinal plants is promising. The traditional use of photo-chemicals from medicinal plants like Amelanchier alnifolia for viral treatment is hopeful. Therefore, it is of interest to screen for flavonoids from Amelanchier alnifolia against protein targets of HCV. Hence, we assessed the binding of flavonoids to HCV NS3/4A protease and helicase proteins. Results show that Quercitin 3- galactoside and 3-glucosideshowed good binding score with protease and helicase respectively. Their interaction/binding sites are documented in this report. This data provide insights for the consideration of flavonoids as potential inhibitors of HCV/NS3/4A protease and helicase.

  7. Conditional Inducible Triple-Transgenic Mouse Model for Rapid Real-Time Detection of HCV NS3/4A Protease Activity

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    Yang, Jing; Zhao, Haiwei; Qiao, Qinghua; Han, Peijun; Xu, Zhikai; Yin, Wen

    2016-01-01

    Hepatitis C virus (HCV) frequently establishes persistent infections that can develop into severe liver disease. The HCV NS3/4A serine protease is not only essential for viral replication but also cleaves multiple cellular targets that block downstream interferon activation. Therefore, NS3/4A is an ideal target for the development of anti-HCV drugs and inhibitors. In the current study, we generated a novel NS3/4A/Lap/LC-1 triple-transgenic mouse model that can be used to evaluate and screen NS3/4A protease inhibitors. The NS3/4A protease could be conditionally inducibly expressed in the livers of the triple-transgenic mice using a dual Tet-On and Cre/loxP system. In this system, doxycycline (Dox) induction resulted in the secretion of Gaussia luciferase (Gluc) into the blood, and this secretion was dependent on NS3/4A protease-mediated cleavage at the 4B5A junction. Accordingly, NS3/4A protease activity could be quickly assessed in real time simply by monitoring Gluc activity in plasma. The results from such monitoring showed a 70-fold increase in Gluc activity levels in plasma samples collected from the triple-transgenic mice after Dox induction. Additionally, this enhanced plasma Gluc activity was well correlated with the induction of NS3/4A protease expression in the liver. Following oral administration of the commercial NS3/4A-specific inhibitors telaprevir and boceprevir, plasma Gluc activity was reduced by 50% and 65%, respectively. Overall, our novel transgenic mouse model offers a rapid real-time method to evaluate and screen potential NS3/4A protease inhibitors. PMID:26943641

  8. Discovery of SCH446211 (SCH6): A New Ketoamide Inhibitor of the HCV NS3 Serine Protease and HCV Subgenomic RNA Replication

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    Bogen, Stephane L.; Arasappan, Ashok; Bennett, Frank; Chen, Kevin; Jao, Edwin; Liu, Yi-Tsung; Lovey, Raymond G.; Venkatraman, Srikanth; Pan, Weidong; Parekh, Tajel; Pike, Russel E.; Ruan, Sumei; Liu, Rong; Baroudy, Bahige; Agrawal, Sony; Chase, Robert; Ingravallo, Paul; Pichardo, John; Prongay, Andrew; Brisson, Jean-Marc; Hsieh, Tony Y.; Cheng, Kuo-Chi; Kemp, Scott J.; Levy, Odile E.; Lim-Wilby, Marguerita; Tamura, Susan Y.; Saksena, Anil K.; Girijavallabhan, Viyyoor; Njoroge, F. George (SPRI)

    2008-06-30

    Introduction of various modified prolines at P{sub 2} and optimization of the P{sub 1} side chain led to the discovery of SCH6 (24, Table 2), a potent ketoamide inhibitor of the HCV NS3 serine protease. In addition to excellent enzyme potency (K*{sub i} = 3.8 nM), 24 was also found to be a potent inhibitor of HCV subgenomic RNA replication with IC{sub 50} and IC{sub 90} of 40 and 100 nM, respectively. Recently, antiviral activity of 24 was demonstrated with inhibition of the full-length genotype 2a HCV genome. In addition, 24 was found to restore the responsiveness of the interferon regulatory factor 3 (IRF-3) in cells containing HCV RNA replicons.

  9. Discovery of SCH446211 (SCH6): a new ketoamide inhibitor of the HCV NS3 serine protease and HCV subgenomic RNA replication.

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    Bogen, Stéphane L; Arasappan, Ashok; Bennett, Frank; Chen, Kevin; Jao, Edwin; Liu, Yi-Tsung; Lovey, Raymond G; Venkatraman, Srikanth; Pan, Weidong; Parekh, Tajel; Pike, Russel E; Ruan, Sumei; Liu, Rong; Baroudy, Bahige; Agrawal, Sony; Chase, Robert; Ingravallo, Paul; Pichardo, John; Prongay, Andrew; Brisson, Jean-Marc; Hsieh, Tony Y; Cheng, Kuo-Chi; Kemp, Scott J; Levy, Odile E; Lim-Wilby, Marguerita; Tamura, Susan Y; Saksena, Anil K; Girijavallabhan, Viyyoor; Njoroge, F George

    2006-05-04

    Introduction of various modified prolines at P(2) and optimization of the P(1) side chain led to the discovery of SCH6 (24, Table 2), a potent ketoamide inhibitor of the HCV NS3 serine protease. In addition to excellent enzyme potency (K(i)*= 3.8 nM), 24 was also found to be a potent inhibitor of HCV subgenomic RNA replication with IC(50) and IC(90) of 40 and 100 nM, respectively. Recently, antiviral activity of 24 was demonstrated with inhibition of the full-length genotype 2a HCV genome. In addition, 24 was found to restore the responsiveness of the interferon regulatory factor 3 (IRF-3) in cells containing HCV RNA replicons.

  10. Different Culture Metabolites of the Red Sea Fungus Fusarium equiseti Optimize the Inhibition of Hepatitis C Virus NS3/4A Protease (HCV PR).

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    Hawas, Usama W; Al-Farawati, Radwan; Abou El-Kassem, Lamia T; Turki, Adnan J

    2016-10-20

    The endophytic fungus Fusarium equiseti was isolated from the brown alga Padina pavonica, collected from the Red Sea. The fungus was identified by its morphology and 18S rDNA. Cultivation of this fungal strain in biomalt-peptone medium led to isolation of 12 known metabolites of diketopeprazines and anthraquinones. The organic extract and isolated compounds were screened for their inhibition of hepatitis C virus NS3/4A protease (HCV PR). As a result, the fungal metabolites showed inhibition of HCV protease (IC50 from 19 to 77 μM), and the fungus was subjected to culture on Czapek's (Cz) media, with a yield of nine metabolites with potent HCV protease inhibition ranging from IC50 10 to 37 μM. The Cz culture extract exhibited high-level inhibition of HCV protease (IC50 27.6 μg/mL) compared to the biomalt culture extract (IC50 56 μg/mL), and the most potent HCV PR isolated compound (Griseoxanthone C, IC50 19.8 μM) from the bio-malt culture extract showed less of an inhibitory effect compared to isolated ω-hydroxyemodin (IC50 10.7 μM) from the optimized Cz culture extract. Both HCV PR active inhibitors ω-hydroxyemodin and griseoxanthone C were considered as the lowest selective safe constituents against Trypsin inhibitory effect with IC50 48.5 and 51.3 μM, respectively.

  11. QSAR studies of the bioactivity of hepatitis C virus (HCV) NS3/4A protease inhibitors by multiple linear regression (MLR) and support vector machine (SVM).

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    Qin, Zijian; Wang, Maolin; Yan, Aixia

    2017-07-01

    In this study, quantitative structure-activity relationship (QSAR) models using various descriptor sets and training/test set selection methods were explored to predict the bioactivity of hepatitis C virus (HCV) NS3/4A protease inhibitors by using a multiple linear regression (MLR) and a support vector machine (SVM) method. 512 HCV NS3/4A protease inhibitors and their IC 50 values which were determined by the same FRET assay were collected from the reported literature to build a dataset. All the inhibitors were represented with selected nine global and 12 2D property-weighted autocorrelation descriptors calculated from the program CORINA Symphony. The dataset was divided into a training set and a test set by a random and a Kohonen's self-organizing map (SOM) method. The correlation coefficients (r 2 ) of training sets and test sets were 0.75 and 0.72 for the best MLR model, 0.87 and 0.85 for the best SVM model, respectively. In addition, a series of sub-dataset models were also developed. The performances of all the best sub-dataset models were better than those of the whole dataset models. We believe that the combination of the best sub- and whole dataset SVM models can be used as reliable lead designing tools for new NS3/4A protease inhibitors scaffolds in a drug discovery pipeline. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Genetic diversity of NS3 protease from Brazilian HCV isolates and possible implications for therapy with direct-acting antiviral drugs

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    Allan Peres-da-Silva

    2012-03-01

    Full Text Available The hepatitis C virus (HCV NS3 protease has been one of the molecular targets of new therapeutic approaches. Its genomic sequence variability in Brazilian HCV isolates is poorly documented. To obtain more information on the magnitude of its genetic diversity, 114 Brazilian HCV samples were sequenced and analysed together with global reference sequences. Genetic distance (d analyses revealed that subtype 1b had a higher degree of heterogeneity (d = 0.098 than subtypes 1a (d = 0.060 and 3a (d = 0.062. Brazilian isolates of subtype 1b were distributed in the phylogenetic tree among sequences from other countries, whereas most subtype 1a and 3a sequences clustered into a single branch. Additional characterisation of subtype 1a in clades 1 and 2 revealed that all but two Brazilian subtype 1a sequences formed a distinct and strongly supported (approximate likelihood-ratio test = 93 group of sequences inside clade 1. Moreover, this subcluster inside clade 1 presented an unusual phenotypic characteristic in relation to the presence of resistance mutations for macrocyclic inhibitors. In particular, the mutation Q80K was found in the majority of clade 1 sequences, but not in the Brazilian isolates. These data demonstrate that Brazilian HCV subtypes display a distinct pattern of genetic diversity and reinforce the importance of sequence information in future therapeutic approaches.

  13. The Combination of Grazoprevir, a Hepatitis C Virus (HCV) NS3/4A Protease Inhibitor, and Elbasvir, an HCV NS5A Inhibitor, Demonstrates a High Genetic Barrier to Resistance in HCV Genotype 1a Replicons.

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    Lahser, Frederick C; Bystol, Karin; Curry, Stephanie; McMonagle, Patricia; Xia, Ellen; Ingravallo, Paul; Chase, Robert; Liu, Rong; Black, Todd; Hazuda, Daria; Howe, Anita Y M; Asante-Appiah, Ernest

    2016-05-01

    The selection of resistance-associated variants (RAVs) against single agents administered to patients chronically infected with hepatitis C virus (HCV) necessitates that direct-acting antiviral agents (DAAs) targeting multiple viral proteins be developed to overcome failure resulting from emergence of resistance. The combination of grazoprevir (formerly MK-5172), an NS3/4A protease inhibitor, and elbasvir (formerly MK-8742), an NS5A inhibitor, was therefore studied in genotype 1a (GT1a) replicon cells. Both compounds were independently highly potent in GT1a wild-type replicon cells, with 90% effective concentration (EC90) values of 0.9 nM and 0.006 nM for grazoprevir and elbasvir, respectively. No cross-resistance was observed when clinically relevant NS5A and NS3 RAVs were profiled against grazoprevir and elbasvir, respectively. Kinetic analyses of HCV RNA reduction over 14 days showed that grazoprevir and elbasvir inhibited prototypic NS5A Y93H and NS3 R155K RAVs, respectively, with kinetics comparable to those for the wild-type GT1a replicon. In combination, grazoprevir and elbasvir interacted additively in GT1a replicon cells. Colony formation assays with a 10-fold multiple of the EC90 values of the grazoprevir-elbasvir inhibitor combination suppressed emergence of resistant colonies, compared to a 100-fold multiple for the independent agents. The selected resistant colonies with the combination harbored RAVs that required two or more nucleotide changes in the codons. Mutations in the cognate gene caused greater potency losses for elbasvir than for grazoprevir. Replicons bearing RAVs identified from resistant colonies showed reduced fitness for several cell lines and may contribute to the activity of the combination. These studies demonstrate that the combination of grazoprevir and elbasvir exerts a potent effect on HCV RNA replication and presents a high genetic barrier to resistance. The combination of grazoprevir and elbasvir is currently approved for

  14. Previous failure of interferon-based therapy does not alter the frequency of HCV NS3 protease or NS5B polymerase inhibitor resistance-associated variants: longitudinal analysis in HCV/HIV co-infected patients.

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    Sede, Mariano M; Laufer, Natalia L; Quarleri, Jorge

    2015-08-01

    Since 2011, treatment of chronic hepatitis C virus (HCV) includes direct-acting antivirals (DAAs) in addition to pegylated interferon-α (peg-IFN) and ribavirin (RBV). IFN-based treatment induces strong cytotoxic T-lymphocyte activity directed to the protease- and polymerase-derived epitopes. This enhanced immunological pressure could favour the emergence of viral epitope variants able to evade immune surveillance and, when resistance-associated variants (RAVs) are implicated, could also be co-selected as a hitchhiking effect. This study analysed the dynamics of the frequency of protease and polymerase inhibitor RAVs that could affect future HCV treatment in human immunodeficiency virus (HIV) co-infected patients on stable antiretroviral therapy with previous IFN-based treatment failure. HCV genotype 1a RNA was extracted from plasma samples of 18 patients prior to and during (24h and 4, 12, 24 and 48 weeks) therapy with peg-IFN+RBV. Next-generation sequencing was performed on HCV-RNA populations using NS3 and NS5B PCR-amplified coding regions. Two measures of genetic diversity were used to compare virus populations: average pairwise nucleotide diversity (π) and Tajima's D statistic. Several protease and polymerase RAVs were detected in all subjects at very low frequencies (<5%), and in most cases their presence was not constant during follow-up. Only samples from two patients for each region exhibited Q80R/K/L and A421V as highly predominant variants. No significant differences were observed among sampling times for either π or D values. In conclusion, previous therapy and failure of peg-IFN+RBV were not associated with an increase in DAA-targeting NS3 or NS5B RAVs that naturally exist in HIV co-infected subjects. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  15. A comparative analysis of the substrate permissiveness of HCV and GBV-B NS3/4A proteases reveals genetic evidence for an interaction with NS4B protein during genome replication.

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    Benureau, Yann; Warter, Lucile; Malcolm, Bruce A; Martin, Annette

    2010-10-25

    The hepatitis C virus (HCV) serine protease (NS3/4A) processes the NS3-NS5B segment of the viral polyprotein and also cleaves host proteins involved in interferon signaling, making it an important target for antiviral drug discovery and suggesting a wide breadth of substrate specificity. We compared substrate specificities of the HCV protease with that of the GB virus B (GBV-B), a distantly related nonhuman primate hepacivirus, by exchanging amino acid sequences at the NS4B/5A and/or NS5A/5B cleavage junctions between these viruses within the backbone of subgenomic replicons. This mutagenesis study demonstrated that the GBV-B protease had a broader substrate tolerance, a feature corroborated by structural homology modeling. However, despite efficient polyprotein processing, GBV-B RNAs containing HCV sequences at the C-terminus of NS4B had a pseudo-lethal replication phenotype. Replication-competent revertants contained second-site substitutions within the NS3 protease or NS4B N-terminus, providing genetic evidence for an essential interaction between NS3 and NS4B during genome replication. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Computer aided screening of Accacia nilotica phytochemicals against HCV NS3/4a.

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    Khan, Mahim; Qasim, Muhammad; Ashfaq, Usman Ali; Idrees, Sobia; Shah, Masoud

    2013-01-01

    HCV has become a leading cause of liver cirrhosis and hepatocellular carcinoma and is a major health concern worldwide. To date, there is no vaccine available in the market to tackle this disease, therefore there is a strong need to develop antiviral compounds that can target all genotypes of HCV with the same efficiency. Medicinal plants have low cost and are less toxic therefore, extracts of medicinal plants can serve as important antiviral agents against HCV. This study was designed to screen phytochemicals of Accacia nilotica to find a potent drug candidate that can inhibit HCV infection effectively. Docking of NS3/4A protease and Flavonoids of Accacia nilotica revealed that most of the flavonoids bound deeply with the active site of NS3/4A protease. Compound 01 showed a high ranking on docking score. All other compounds also showed reliable docking scores and had interactions with the binding cavity of NS3/4A protease, suggesting them as a potent drug candidate to block HCV replication. To recognize binding interactions of Accacia nilotica phytochemicals with NS3/4A protease, molecular docking was performed to find potential inhibitor against NS3/4A protease of HCV. After post docking analysis, important interactions were found between active compounds and active site of NS3/4A protease. It can be concluded from the study that phytochemicals of Accacia nilotica may serve as a potential drug candidate with relatively simple structural changes against HCV NS3/4A protease.

  17. Hepatitis C virus NS3/4A protease inhibits complement activation by cleaving complement component 4.

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    Seiichi Mawatari

    Full Text Available BACKGROUND: It has been hypothesized that persistent hepatitis C virus (HCV infection is mediated in part by viral proteins that abrogate the host immune response, including the complement system, but the precise mechanisms are not well understood. We investigated whether HCV proteins are involved in the fragmentation of complement component 4 (C4, composed of subunits C4α, C4β, and C4γ, and the role of HCV proteins in complement activation. METHODS: Human C4 was incubated with HCV nonstructural (NS 3/4A protease, core, or NS5. Samples were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and then subjected to peptide sequencing. The activity of the classical complement pathway was examined using an erythrocyte hemolysis assay. The cleavage pattern of C4 in NS3/4A-expressing and HCV-infected cells, respectively, was also examined. RESULTS: HCV NS3/4A protease cleaved C4γ in a concentration-dependent manner, but viral core and NS5 did not. A specific inhibitor of NS3/4A protease reduced C4γ cleavage. NS3/4A protease-mediated cleavage of C4 inhibited classical pathway activation, which was abrogated by a NS3/4A protease inhibitor. In addition, co-transfection of cells with C4 and wild-type NS3/4A, but not a catalytic-site mutant of NS3/4A, produced cleaved C4γ fragments. Such C4 processing, with a concomitant reduction in levels of full-length C4γ, was also observed in HCV-infected cells expressing C4. CONCLUSIONS: C4 is a novel cellular substrate of the HCV NS3/4A protease. Understanding disturbances in the complement system mediated by NS3/4A protease may provide new insights into the mechanisms underlying persistent HCV infection.

  18. Variability and resistance mutations in the hepatitis C virus NS3 protease in patients not treated with protease inhibitors

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    Luciana Bonome Zeminian

    2013-02-01

    Full Text Available The goal of treatment of chronic hepatitis C is to achieve a sustained virological response, which is defined as exhibiting undetectable hepatitis C virus (HCV RNA levels in serum following therapy for at least six months. However, the current treatment is only effective in 50% of patients infected with HCV genotype 1, the most prevalent genotype in Brazil. Inhibitors of the serine protease non-structural protein 3 (NS3 have therefore been developed to improve the responses of HCV-infected patients. However, the emergence of drug-resistant variants has been the major obstacle to therapeutic success. The goal of this study was to evaluate the presence of resistance mutations and genetic polymorphisms in the NS3 genomic region of HCV from 37 patients infected with HCV genotype 1 had not been treated with protease inhibitors. Plasma viral RNA was used to amplify and sequence the HCV NS3 gene. The results indicate that the catalytic triad is conserved. A large number of substitutions were observed in codons 153, 40 and 91; the resistant variants T54A, T54S, V55A, R155K and A156T were also detected. This study shows that resistance mutations and genetic polymorphisms are present in the NS3 region of HCV in patients who have not been treated with protease inhibitors, data that are important in determining the efficiency of this new class of drugs in Brazil.

  19. Canine hepacivirus NS3 serine protease can cleave the human adaptor proteins MAVS and TRIF.

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    Mariona Parera

    Full Text Available Canine hepacivirus (CHV was recently identified in domestic dogs and horses. The finding that CHV is genetically the virus most closely related to hepatitis C virus (HCV has raised the question of whether HCV might have evolved as the result of close contact between dogs and/or horses and humans. The aim of this study was to investigate whether the NS3/4A serine protease of CHV specifically cleaves human mitochondrial antiviral signaling protein (MAVS and Toll-IL-1 receptor domain-containing adaptor inducing interferon-beta (TRIF. The proteolytic activity of CHV NS3/4A was evaluated using a bacteriophage lambda genetic screen. Human MAVS- and TRIF-specific cleavage sites were engineered into the lambda cI repressor. Upon infection of Escherichia coli cells coexpressing these repressors and a CHV NS3/4A construct, lambda phage replicated up to 2000-fold more efficiently than in cells expressing a CHV protease variant carrying the inactivating substitution S139A. Comparable results were obtained when several HCV NS3/4A constructs of genotype 1b were assayed. This indicates that CHV can disrupt the human innate antiviral defense signaling pathway and suggests a possible evolutionary relationship between CHV and HCV.

  20. Molecular models of NS3 protease variants of the Hepatitis C virus

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    Mello Isabel MVGC

    2005-01-01

    Full Text Available Abstract Background Hepatitis C virus (HCV currently infects approximately three percent of the world population. In view of the lack of vaccines against HCV, there is an urgent need for an efficient treatment of the disease by an effective antiviral drug. Rational drug design has not been the primary way for discovering major therapeutics. Nevertheless, there are reports of success in the development of inhibitor using a structure-based approach. One of the possible targets for drug development against HCV is the NS3 protease variants. Based on the three-dimensional structure of these variants we expect to identify new NS3 protease inhibitors. In order to speed up the modeling process all NS3 protease variant models were generated in a Beowulf cluster. The potential of the structural bioinformatics for development of new antiviral drugs is discussed. Results The atomic coordinates of crystallographic structure 1CU1 and 1DY9 were used as starting model for modeling of the NS3 protease variant structures. The NS3 protease variant structures are composed of six subdomains, which occur in sequence along the polypeptide chain. The protease domain exhibits the dual beta-barrel fold that is common among members of the chymotrypsin serine protease family. The helicase domain contains two structurally related beta-alpha-beta subdomains and a third subdomain of seven helices and three short beta strands. The latter domain is usually referred to as the helicase alpha-helical subdomain. The rmsd value of bond lengths and bond angles, the average G-factor and Verify 3D values are presented for NS3 protease variant structures. Conclusions This project increases the certainty that homology modeling is an useful tool in structural biology and that it can be very valuable in annotating genome sequence information and contributing to structural and functional genomics from virus. The structural models will be used to guide future efforts in the structure

  1. Hepatitis C Virus NS3/4A Protease Inhibitors: A Light at the End of the Tunnel

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    Laurent Chatel-Chaix

    2010-08-01

    Full Text Available Hepatitis C virus (HCV infection is a serious and growing threat to human health. The current treatment provides limited efficacy and is poorly tolerated, highlighting the urgent medical need for novel therapeutics. The membrane-targeted NS3 protein in complex with the NS4A comprises a serine protease domain (NS3/4A protease that is essential for viral polyprotein maturation and contributes to the evasion of the host innate antiviral immunity by HCV. Therefore, the NS3/4A protease represents an attractive target for drug discovery, which is tied in with the challenge to develop selective small-molecule inhibitors. A rational drug design approach, based on the discovery of N-terminus product inhibition, led to the identification of potent and orally bioavailable NS3 inhibitors that target the highly conserved protease active site. This review summarizes the NS3 protease inhibitors currently challenged in clinical trials as one of the most promising antiviral drug class, and possibly among the first anti-HCV agents to be approved for the treatment of HCV infection.

  2. Biliverdin Inhibits Hepatitis C Virus NS3/4A Protease Activity: Mechanism for the Antiviral Effects of Heme Oxygenase?

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    Zhu, Zhaowen; Wilson, Anne T.; Luxon, Bruce A.; Brown, Kyle E.; Mathahs, M. Meleah; Bandyopadhyay, Sarmistha; McCaffrey, Anton P.; Schmidt, Warren N.

    2010-01-01

    Induction of heme oxygenase -1 (HO-1) inhibits hepatitis C virus (HCV) replication. Of the products of the reaction catalyzed by HO-1 iron has been shown to inhibit HCV RNA polymerase, but little is known about the antiviral activity of biliverdin (BV). Herein, we report that BV inhibits viral replication and viral protein expression in a dose-dependent manner in replicons and cells harboring the infectious J6/JFH construct. Using the SensoLyte 620 HCV Protease Assay with a wide wavelength excitation/emission (591nm/622nm) fluorescence energy transfer peptide, we found that both recombinant and endogenous NS3/4A protease from replicon microsomes are potently inhibited by BV. Of the tetrapyrroles tested, BV was the strongest inhibitor of NS3/4A activity with an IC50 of 9 uM, similar to that of the commercial inhibitor, AnaSpec #25346 (IC50 5 uM). Lineweaver-Burk plots indicated mixed competitive and non-competitive inhibition of the protease by BV. In contrast, the effects of bilirubin (BR) on HCV replication and NS3/4A were much less potent. Because BV is rapidly converted to BR by biliverdin reductase (BVR) intracellularly, the effect of BVR knockdown on BV antiviral activity was assessed. After >80% silencing of BVR, inhibition of viral replication by BV was enhanced. BV also increased the antiviral activity of α-interferon in replicons. Conclusion BV is a potent inhibitor of HCV NS3/4A protease, which likely contributes to the antiviral activity of HO-1. These findings suggest that BV or its derivatives may be useful future drug therapies targeting the NS3/4A protease. PMID:21105106

  3. Pharmacophore anchor models of flaviviral NS3 proteases lead to drug repurposing for DENV infection.

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    Pathak, Nikhil; Lai, Mei-Ling; Chen, Wen-Yu; Hsieh, Betty-Wu; Yu, Guann-Yi; Yang, Jinn-Moon

    2017-12-28

    Viruses of the flaviviridae family are responsible for some of the major infectious viral diseases around the world and there is an urgent need for drug development for these diseases. Most of the virtual screening methods in flaviviral drug discovery suffer from a low hit rate, strain-specific efficacy differences, and susceptibility to resistance. It is because they often fail to capture the key pharmacological features of the target active site critical for protein function inhibition. So in our current work, for the flaviviral NS3 protease, we summarized the pharmacophore features at the protease active site as anchors (subsite-moiety interactions). For each of the four flaviviral NS3 proteases (i.e., HCV, DENV, WNV, and JEV), the anchors were obtained and summarized into 'Pharmacophore anchor (PA) models'. To capture the conserved pharmacophore anchors across these proteases, were merged the four PA models. We identified five consensus core anchors (CEH1, CH3, CH7, CV1, CV3) in all PA models, represented as the "Core pharmacophore anchor (CPA) model" and also identified specific anchors unique to the PA models. Our PA/CPA models complied with 89 known NS3 protease inhibitors. Furthermore, we proposed an integrated anchor-based screening method using the anchors from our models for discovering inhibitors. This method was applied on the DENV NS3 protease to screen FDA drugs discovering boceprevir, telaprevir and asunaprevir as promising anti-DENV candidates. Experimental testing against DV2-NGC virus by in-vitro plaque assays showed that asunaprevir and telaprevir inhibited viral replication with EC50 values of 10.4 μM & 24.5 μM respectively. The structure-anchor-activity relationships (SAAR) showed that our PA/CPA model anchors explained the observed in-vitro activities of the candidates. Also, we observed that the CEH1 anchor engagement was critical for the activities of telaprevir and asunaprevir while the extent of inhibitor anchor occupation guided

  4. Generation and Characterization of a Hepatitis C Virus NS3 Protease-Dependent Bovine Viral Diarrhea Virus

    Science.gov (United States)

    Lai, Vicky C. H.; Zhong, Weidong; Skelton, Angela; Ingravallo, Paul; Vassilev, Venteislav; Donis, Ruben O.; Hong, Zhi; Lau, Johnson Y. N.

    2000-01-01

    Unique to pestiviruses, the N-terminal protein encoded by the bovine viral diarrhea virus (BVDV) genome is a cysteine protease (Npro) responsible for a self-cleavage that releases the N terminus of the core protein (C). This unique protease is dispensable for viral replication, and its coding region can be replaced by a ubiquitin gene directly fused in frame to the core. To develop an antiviral assay that allows the assessment of anti-hepatitis C virus (HCV) NS3 protease inhibitors, a chimeric BVDV in which the coding region of Npro was replaced by that of an NS4A cofactor-tethered HCV NS3 protease domain was generated. This cofactor-tethered HCV protease domain was linked in frame to the core protein of BVDV through an HCV NS5A-NS5B junction site and mimicked the proteolytic function of Npro in the release of BVDV core for capsid assembly. A similar chimeric construct was built with an inactive HCV NS3 protease to serve as a control. Genomic RNA transcripts derived from both chimeric clones, PH/B (wild-type HCV NS3 protease) and PH/B(S139A) (mutant HCV NS3 protease) were then transfected into bovine cells (MDBK). Only the RNA transcripts from the PH/B clone yielded viable viruses, whereas the mutant clone, PH/B(S139A), failed to produce any signs of infection, suggesting that the unprocessed fusion protein rendered the BVDV core protein defective in capsid assembly. Like the wild-type BVDV (NADL), the chimeric virus was cytopathic and formed plaques on the cell monolayer. Sequence and biochemical analyses confirmed the identity of the chimeric virus and further revealed variant viruses due to growth adaptation. Growth analysis revealed comparable replication kinetics between the wild-type and the chimeric BVDVs. Finally, to assess the genetic stability of the chimeric virus, an Npro-null BVDV (BVDV−Npro in which the entire Npro coding region was deleted) was produced. Although cytopathic, BVDV−Npro was highly defective in viral replication and growth, a

  5. Effect of disease state on ionization during bioanalysis of MK-7009, a selective HCV NS3/NS4 protease inhibitor, in human plasma and human Tween-treated urine by high-performance liquid chromatography with tandem mass spectrometric detection.

    Science.gov (United States)

    Anderson, M D G; Breidinger, S A; Woolf, E J

    2009-04-15

    HPLC-MS/MS methods for the determination of a Hepatitis C NS3/NS4 protease inhibitor (MK-7009) in human plasma and Tween-treated urine were developed and validated over the concentration range 1-1000 ng/mL and 0.2-100 microg/mL respectively. A stable isotope labeled internal standard (ISTD), D(4)-MK-7009, was employed. Analytes were chromatographed by reversed phase HPLC and quantified by an MS/MS system. Electrospray ionization in the positive mode was employed. Multiple reaction monitoring of the precursor to product ion pairs m/z 758.6-->637.4 MK-7009 and m/z 762.5-->637.4 ISTD was used for quantitation. Analyte and internal standard were extracted from 250 microL of plasma using an automated 96-well liquid-liquid extraction. Plasma pH adjustment prior to extraction minimized ionization suppression in plasma samples from patients with Hepatitis C. The urine method involved direct dilution in the 96-well format of 0.020 mL Tween-treated urine. These methods have supported several clinical studies. Incurred plasma sample reanalysis demonstrated adequate assay reproducibility and ruggedness.

  6. In vitro antiviral activity of SCH446211 (SCH6), a novel inhibitor of the hepatitis C virus NS3 serine protease.

    Science.gov (United States)

    Liu, Rong; Abid, Karim; Pichardo, John; Pazienza, Valerio; Ingravallo, Paul; Kong, Rong; Agrawal, Sony; Bogen, Stephane; Saksena, Anil; Cheng, Kuo-Chi; Prongay, Andrew; Njoroge, F George; Baroudy, Bahige M; Negro, Francesco

    2007-01-01

    Current hepatitis C virus (HCV) therapies may cure approximately 60% of infections. They are often contraindicated or poorly tolerated, underscoring the need for safer and more effective drugs. A novel, alpha-ketoamide-derived, substrate-based inhibitor of the HCV serine protease (SCH446211) was developed. Compared with earlier reported inhibitors of similar chemical class, it has a P1'-P2' extension which provides extended interaction with the protease active site. The aim of this study was to evaluate the in vitro antiviral activity of SCH446211. Binding constant of SCH446211 to HCV NS3 protease was measured with the chromogenic substrate in vitro cleavage assay. Cell-based activity of SCH446211 was evaluated in replicon cells, which are Huh-7 hepatoma cells stably transfected with a subgenomic HCV RNA as reported previously. After 72 h of incubation with SCH446211, viral transcription and protein expression were measured by real-time RT-PCR (TaqMan), quantitative in situ hybridization, immunoblot and indirect immunofluorescence. The binding constant of SCH446211 to HCV NS3 protease was 3.8 +/- 0.4 nM. HCV replication and protein expression were inhibited by SCH446211 in replicon cells as consistently shown by four techniques. In particular, based on quantitative real-time RT-PCR measurements, the IC50 and IC90 of SCH446211 were estimated to be 40 +/- 20 and 100 +/- 20 nM (n = 17), respectively. Long-term culture of replicon cells with SCH446211 reduced replicon RNA to <0.1 copy per cell. SCH446211 did not show cellular toxicity at concentrations up to 50 microM. SCH446211 is a potent inhibitor of HCV protease in vitro. Its extended interaction with the HCV NS3 protease active site is associated with potent in vitro antiviral activity. This observation is potentially a useful guide for development of future potent inhibitors against HCV NS3 protease.

  7. Identification of novel small molecule inhibitors against NS2B/NS3 serine protease from Zika virus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun; Ren, Jinhong; Nocadello, Salvatore; Rice, Amy J.; Ojeda, Isabel; Light, Samuel; Minasov, George; Vargas, Jason; Nagarathnam, Dhanapalan; Anderson, Wayne F.; Johnson, Michael E. (UIC); (NWU); (Novalex); (DNSK)

    2016-12-26

    Zika flavivirus infection during pregnancy appears to produce higher risk of microcephaly, and also causes multiple neurological problems such as Guillain–Barré syndrome. The Zika virus is now widespread in Central and South America, and is anticipated to become an increasing risk in the southern United States. With continuing global travel and the spread of the mosquito vector, the exposure is expected to accelerate, but there are no currently approved treatments against the Zika virus. The Zika NS2B/NS3 protease is an attractive drug target due to its essential role in viral replication. Our studies have identified several compounds with inhibitory activity (IC50) and binding affinity (KD) of ~5–10 μM against the Zika NS2B-NS3 protease from testing 71 HCV NS3/NS4A inhibitors that were initially discovered by high-throughput screening of 40,967 compounds. Competition surface plasmon resonance studies and mechanism of inhibition analyses by enzyme kinetics subsequently determined the best compound to be a competitive inhibitor with a Ki value of 9.5 μM. We also determined the X-ray structure of the Zika NS2B-NS3 protease in a “pre-open conformation”, a conformation never observed before for any flavivirus proteases. This provides the foundation for new structure-based inhibitor design.

  8. NS3 Resistance-Associated Variants (RAVs in Patients Infected with HCV Genotype 1a in Spain.

    Directory of Open Access Journals (Sweden)

    María Ángeles Jimenez-Sousa

    Full Text Available Resistance-associated variants have been related to treatment failure of hepatitis C virus (HCV therapy with direct-acting antiviral drugs. The aim of our study was to analyze the prevalence of clinically relevant resistance-associated variants within NS3 in patients infected with HCV genotype 1a (GT1a in Spain.We performed a cross-sectional study on 2568 patients from 115 hospitals throughout Spain (2014-2015. The viral NS3 protease gene was amplified by nested polymerase chain reaction and sequenced by Sanger sequencing using an ABI PRISM 377 DNA sequencer. Additionally, clade information for genotype 1a was obtained by using the software geno2pheno (http://hcv.geno2pheno.org/.In total, 875 out of 2568 samples were from human immunodeficiency virus (HIV/HCV-coinfected patients. Q80K was the main RAV found in our patients (11.1% and the rest of the resistance-associated variants had a lower frequency, including S122G (6.23%, T54S (3.47%, V55A (2.61%, and V55I (2.15%, which were among the most frequent after Q80K. Overall, 286 samples had the Q80K polymorphism (11.1% and 614 (23.9% were GT1a clade I. HIV/HCV-coinfected patients had a higher frequency of Q80K and GT1a clade I than HCV-monoinfected patients (12.9% vs. 9.6% [p = 0.012] and 28.5% vs. 21.4% [p<0.001], respectively. Both the prevalence of Q80K and GT1a clade I were not uniform throughout the country (p<0.001, which ranged from 7.3%-22.2% and 15.7%-42.5%, respectively. The frequency of the Q80K polymorphism was far higher in patients infected with GT1a clade I than in patients infected with GT1a clade II (41.5% vs. 1.6%; p<0.001.The prevalence of most resistance-associated variants in NS3 was low in patients infected with HCV GT1a in Spain, except for Q80K (11.1%, which was also notably higher in HIV/HCV-coinfected patients. The vast majority of Q80K polymorphisms were detected in GT1a clade I.

  9. The GB virus C (GBV-C NS3 serine protease inhibits HIV-1 replication in a CD4+ T lymphocyte cell line without decreasing HIV receptor expression.

    Directory of Open Access Journals (Sweden)

    Sarah L George

    Full Text Available INTRODUCTION: Persistent infection with GBV-C (GB Virus C, a non-pathogenic virus related to hepatitis C virus (HCV, prolongs survival in HIV infection. Two GBV-C proteins, NS5A and E2, have been shown previously to inhibit HIV replication in vitro. We investigated whether the GBV-C NS3 serine protease affects HIV replication. RESULTS: GBV-C NS3 protease expressed in a human CD4+ T lymphocyte cell line significantly inhibited HIV replication. Addition of NS4A or NS4A/4B coding sequence to GBV-C NS3 increased the effect on HIV replication. Inhibition of HIV replication was dose-dependent and was not mediated by increased cell toxicity. Mutation of the NS3 catalytic serine to alanine resulted in loss of both HIV inhibition and protease activity. GBV-C NS3 expression did not measurably decrease CD4 or CXCR4 expression. CONCLUSION: GBV-C NS3 serine protease significantly inhibited HIV replication without decreasing HIV receptor expression. The requirement for an intact catalytic serine at the active site indicates that inhibition was mediated by proteolytic cleavage of an unidentified target(s.

  10. The GB virus C (GBV-C) NS3 serine protease inhibits HIV-1 replication in a CD4+ T lymphocyte cell line without decreasing HIV receptor expression.

    Science.gov (United States)

    George, Sarah L; Varmaz, Dino; Tavis, John E; Chowdhury, Adnan

    2012-01-01

    Persistent infection with GBV-C (GB Virus C), a non-pathogenic virus related to hepatitis C virus (HCV), prolongs survival in HIV infection. Two GBV-C proteins, NS5A and E2, have been shown previously to inhibit HIV replication in vitro. We investigated whether the GBV-C NS3 serine protease affects HIV replication. GBV-C NS3 protease expressed in a human CD4+ T lymphocyte cell line significantly inhibited HIV replication. Addition of NS4A or NS4A/4B coding sequence to GBV-C NS3 increased the effect on HIV replication. Inhibition of HIV replication was dose-dependent and was not mediated by increased cell toxicity. Mutation of the NS3 catalytic serine to alanine resulted in loss of both HIV inhibition and protease activity. GBV-C NS3 expression did not measurably decrease CD4 or CXCR4 expression. GBV-C NS3 serine protease significantly inhibited HIV replication without decreasing HIV receptor expression. The requirement for an intact catalytic serine at the active site indicates that inhibition was mediated by proteolytic cleavage of an unidentified target(s).

  11. Unraveling the structural basis of grazoprevir potency against clinically relevant substitutions in hepatitis C virus NS3/4A protease from genotype 1a.

    Science.gov (United States)

    Guo, Zhuyan; Black, Stuart; Hu, Yuan; McMonagle, Patricia; Ingravallo, Paul; Chase, Robert; Curry, Stephanie; Asante-Appiah, Ernest

    2017-04-14

    Grazoprevir is a potent pan-genotype and macrocyclic inhibitor of hepatitis C virus (HCV) NS3/4A protease and was developed for treating chronic HCV infection. In HCV genotype (GT) 1a, grazoprevir maintains potent activity against a majority of NS3 resistance-associated amino acid substitutions, including the highly prevalent and naturally occurring Q80K polymorphism that impacts simeprevir, another NS3/4A protease inhibitor. The basis for an unexpected difference in the clinical impact of some NS3 substitutions was investigated. Phenotypic analysis of resistance-associated substitutions identified in NS3 from GT1a-infected patients who failed therapy with grazoprevir (in combination with elbasvir, an inhibitor of HCV NS5A protein) showed that positions 56, 156, and 168 in NS3 were most impactful because they diminished protein-inhibitor interactions. Although an amino acid substitution from aspartic acid to alanine at position 168 (D168A) reduced the potency of grazoprevir, its combination with R155K unexpectedly nullified this effect. Molecular dynamics and free-energy surface studies indicated that Asp-168 is important in anchoring Arg-155 for ligand binding but is not critical for Lys-155 because of the inherent flexibility of its side chain. Moreover, modeling studies supported a strong direct cation-heterocycle interaction between the Lys-155 side chain of the double substitution, R155K/D168A, and the lone pair on the quinoxaline in grazoprevir. This unique interaction provides a structural basis for grazoprevir's higher potency than simeprevir, an inhibitor to which the double substitution confers a significant reduction in potency. Our findings are consistent with the detection of R155K/D168A in NS3 from virologic failures treated with simeprevir but not grazoprevir. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. New binding site conformations of the dengue virus NS3 protease accessed by molecular dynamics simulation.

    Directory of Open Access Journals (Sweden)

    Hugo de Almeida

    Full Text Available Dengue fever is caused by four distinct serotypes of the dengue virus (DENV1-4, and is estimated to affect over 500 million people every year. Presently, there are no vaccines or antiviral treatments for this disease. Among the possible targets to fight dengue fever is the viral NS3 protease (NS3PRO, which is in part responsible for viral processing and replication. It is now widely recognized that virtual screening campaigns should consider the flexibility of target protein by using multiple active conformational states. The flexibility of the DENV NS3PRO could explain the relatively low success of previous virtual screening studies. In this first work, we explore the DENV NS3PRO conformational states obtained from molecular dynamics (MD simulations to take into account protease flexibility during the virtual screening/docking process. To do so, we built a full NS3PRO model by multiple template homology modeling. The model comprised the NS2B cofactor (essential to the NS3PRO activation, a glycine flexible link and the proteolytic domain. MD simulations had the purpose to sample, as closely as possible, the ligand binding site conformational landscape prior to inhibitor binding. The obtained conformational MD sample was clustered into four families that, together with principal component analysis of the trajectory, demonstrated protein flexibility. These results allowed the description of multiple binding modes for the Bz-Nle-Lys-Arg-Arg-H inhibitor, as verified by binding plots and pair interaction analysis. This study allowed us to tackle protein flexibility in our virtual screening campaign against the dengue virus NS3 protease.

  13. Establishment of a novel triple-transgenic mouse: conditionally and liver-specifically expressing hepatitis C virus NS3/4A protease.

    Science.gov (United States)

    Lan, H Y; Zhao, Y; Yang, J; Sun, M N; Lei, Y F; Yao, M; Huang, X J; Zhang, J M; Xu, Z K; Lü, X; Yin, W

    2014-11-01

    It is well known that NS3/4A protein plays crucial roles in the hepatitis C virus (HCV) replication. NS3/4A protein also results to virus-mediated immune evasion and persistence of infection through the interaction with host proteins. However, the lack of a suitable animal model hampers studies of HCV NS3/4A protein interaction with host proteins, which impacts immunopathology due to infection. Here, transgenic vector containing transcriptional regulation and Fluc reporter gene was constructed to conditionally express NS3/4A protein under the dual control of Tet-On regulatory system and Cre/LoxP gene-knockout system. NS3/4A transgenic founder mice were continuously crossed with Lap transgenic mice expressing reverse tetracycline-controlled transcriptional activator (rtTA), the NS3/4A/Lap double transgenic mouse lines with liver-specifically and conditionally expressing reporter (luciferase Fluc) under control of Tet-On system were established. The NS3/4A/Lap double transgenic mouse are mated with Lap/LC-1 double transgenic mouse with liver-specifically and conditionally expressing Cre recombinase under control of Tet-On system, NS3/4A/Lap/LC-1 triple transgenic mouse were generated. In vivo bioluminescent imaging, western blotting and immunohistochemical staining (IHS) was used to confirm that NS3/4A protein was strictly expressed in the liver of Doxycycline-induced triple transgenic mice. The results show that we established a triple-transgenic mouse model conditionally expressing the HCV NS3/4A protein under strict control of the Tet-On regulatory system and Cre/loxP system. This novel transgenic mouse model expressing NS3/4A in a temporally and spatially-specific manner will be useful for studying interactions between HCV NS3/4A protein and the host, also for evaluating NS3/4A protease inhibitors.

  14. Hepacivirus NS3/4A Proteases Interfere with MAVS Signaling in both Their Cognate Animal Hosts and Humans: Implications for Zoonotic Transmission.

    Science.gov (United States)

    Anggakusuma; Brown, Richard J P; Banda, Dominic H; Todt, Daniel; Vieyres, Gabrielle; Steinmann, Eike; Pietschmann, Thomas

    2016-12-01

    Multiple novel members of the genus Hepacivirus have recently been discovered in diverse mammalian species. However, to date, their replication mechanisms and zoonotic potential have not been explored in detail. The NS3/4A serine protease of hepatitis C virus (HCV) is critical for cleavage of the viral polyprotein. It also cleaves the cellular innate immune adaptor MAVS, thus decreasing interferon (IFN) production and contributing to HCV persistence in the human host. To investigate the conservation of fundamental aspects of the hepaciviral life cycle, we explored if MAVS cleavage and suppression of innate immune signaling represent a common mechanism employed across different clades of the genus Hepacivirus to enhance viral replication. To estimate the zoonotic potential of these nonhuman hepaciviruses, we assessed if their NS3/4A proteases were capable of cleaving human MAVS. NS3/4A proteases of viruses infecting colobus monkeys, rodents, horses, and cows cleaved the MAVS proteins of their cognate hosts and interfered with the ability of MAVS to induce the IFN-β promoter. All NS3/4A proteases from nonhuman viruses readily cleaved human MAVS. Thus, NS3/4A-dependent cleavage of MAVS is a conserved replication strategy across multiple clades within the genus Hepacivirus Human MAVS is susceptible to cleavage by these nonhuman viral proteases, indicating that it does not pose a barrier for zoonotic transmission of these viruses to humans. Virus infection is recognized by cellular sensor proteins triggering innate immune signaling and antiviral defenses. While viruses have evolved strategies to thwart these antiviral programs in their cognate host species, these evasion mechanisms are often ineffective in a novel host, thus limiting viral transmission across species. HCV, the best-characterized member of the genus Hepacivirus within the family Flaviviridae, uses its NS3/4A protease to disrupt innate immune signaling by cleaving the cellular adaptor protein MAVS

  15. Four Aromatic Sulfates with an Inhibitory Effect against HCV NS3 Helicase from the Crinoid Alloeocomatella polycladia

    Science.gov (United States)

    Hermawan, Idam; Furuta, Atsushi; Higashi, Masahiro; Fujita, Yoshihisa; Akimitsu, Nobuyoshi; Yamashita, Atsuya; Moriishi, Kohji; Tsuneda, Satoshi; Tani, Hidenori; Nakakoshi, Masamichi; Tsubuki, Masayoshi; Sekiguchi, Yuji; Noda, Naohiro; Tanaka, Junichi

    2017-01-01

    Bioassay-guided separation of a lipophilic extract of the crinoid Alloeocomatella polycladia, inhibiting the activity of HCV NS3 helicase, yielded two groups of molecules: cholesterol sulfate and four new aromatic sulfates 1–4. The structures of the aromatics were elucidated by spectroscopic analysis in addition to theoretical studies. The aromatic sulfates 1–4 showed moderate inhibition against NS3 helicase with IC50 values of 71, 95, 7, and 5 μM, respectively. PMID:28398249

  16. Single- and multiple-ascending-dose studies of the NS3 protease inhibitor asunaprevir in subjects with or without chronic hepatitis C.

    Science.gov (United States)

    Pasquinelli, Claudio; McPhee, Fiona; Eley, Timothy; Villegas, Criselda; Sandy, Katrina; Sheridan, Pamela; Persson, Anna; Huang, Shu-Pang; Hernandez, Dennis; Sheaffer, Amy K; Scola, Paul; Marbury, Thomas; Lawitz, Eric; Goldwater, Ronald; Rodriguez-Torres, Maribel; Demicco, Michael; Wright, David; Charlton, Michael; Kraft, Walter K; Lopez-Talavera, Juan-Carlos; Grasela, Dennis M

    2012-04-01

    Hepatitis C virus (HCV) protease inhibitors combined with pegylated alfa interferon-ribavirin have demonstrated improved efficacy compared with pegylated alfa interferon-ribavirin alone for the treatment of chronic hepatitis C. Asunaprevir (BMS-650032), a novel HCV NS3 protease inhibitor in clinical development, was evaluated for safety, antiviral activity, and resistance in four double-blind, placebo-controlled, sequential-panel, single- and multiple-ascending-dose (SAD and MAD) studies in healthy subjects or subjects with chronic HCV genotype 1 infection. In SAD studies, subjects (healthy or with chronic HCV infection) were randomized to receive asunaprevir in dose groups of 10 to 1,200 mg or a placebo. In MAD studies, healthy subjects were randomized to receive asunaprevir in dose groups of 10 to 600 mg twice daily or a placebo for 14 days; subjects with HCV infection received asunaprevir in dose groups of 200 to 600 mg twice daily, or a placebo, for 3 days. Across all four studies, headache and diarrhea were the most frequent adverse events in asunaprevir recipients. Asunaprevir at doses of 200 to 600 mg resulted in rapid HCV RNA decreases from the baseline; maximal mean changes in HCV RNA over time were 2.7 and 3.5 log(10) IU/ml in the SAD and MAD studies, respectively. No enrichment of signature asunaprevir-resistant viral variants was detected. In conclusion, the novel NS3 protease inhibitor asunaprevir, when administered at single or multiple doses of 200 to 600 mg twice daily, is generally well tolerated, achieving rapid and substantial decreases in HCV RNA levels in subjects chronically infected with genotype 1 HCV.

  17. SCH 503034, a mechanism-based inhibitor of hepatitis C virus NS3 protease, suppresses polyprotein maturation and enhances the antiviral activity of alpha interferon in replicon cells.

    Science.gov (United States)

    Malcolm, B A; Liu, R; Lahser, F; Agrawal, S; Belanger, B; Butkiewicz, N; Chase, R; Gheyas, F; Hart, A; Hesk, D; Ingravallo, P; Jiang, C; Kong, R; Lu, J; Pichardo, J; Prongay, A; Skelton, A; Tong, X; Venkatraman, S; Xia, E; Girijavallabhan, V; Njoroge, F G

    2006-03-01

    Cleavage of the hepatitis C virus (HCV) polyprotein by the viral NS3 protease releases functional viral proteins essential for viral replication. Recent studies by Foy and coworkers strongly suggest that NS3-mediated cleavage of host factors may abrogate cellular response to alpha interferon (IFN-alpha) (E. Foy, K. Li, R. Sumpter, Jr., Y.-M. Loo, C. L. Johnson, C. Wang, P. M. Fish, M. Yoneyama, T. Fujita, S. M. Lemon, and M. Gale, Jr., Proc. Natl. Acad. Sci. USA 102:2986-2991, 2005, and E. Foy, K. Li, C. Wang, R. Sumpter, Jr., M. Ikeda, S. M. Lemon, and M. Gale, Jr., Science 300:1145-1148, 2003). Blockage of NS3 protease activity therefore is expected to inhibit HCV replication by both direct suppression of viral protein production as well as by restoring host responsiveness to IFN. Using structure-assisted design, a ketoamide inhibitor, SCH 503034, was generated which demonstrated potent (overall inhibition constant, 14 nM) time-dependent inhibition of the NS3 protease in cell-free enzyme assays as well as robust in vitro activity in the HCV replicon system, as monitored by immunofluorescence and real-time PCR analysis. Continuous exposure of replicon-bearing cell lines to six times the 90% effective concentration of SCH 503034 for 15 days resulted in a greater than 4-log reduction in replicon RNA. The combination of SCH 503034 with IFN was more effective in suppressing replicon synthesis than either compound alone, supporting the suggestion of Foy and coworkers that combinations of IFN with protease inhibitors would lead to enhanced therapeutic efficacy.

  18. Exploring resistance pathways for first-generation NS3/4A protease inhibitors boceprevir and telaprevir using Bayesian network learning.

    Science.gov (United States)

    Cuypers, Lize; Libin, Pieter; Schrooten, Yoeri; Theys, Kristof; Di Maio, Velia Chiara; Cento, Valeria; Lunar, Maja M; Nevens, Frederik; Poljak, Mario; Ceccherini-Silberstein, Francesca; Nowé, Ann; Van Laethem, Kristel; Vandamme, Anne-Mieke

    2017-09-01

    Resistance-associated variants (RAVs) have been shown to influence treatment response to direct-acting antivirals (DAAs) and first generation NS3/4A protease inhibitors (PIs) in particular. Interpretation of hepatitis C virus (HCV) genotypic drug resistance remains a challenge, especially in patients who previously failed DAA therapy and need to be retreated with a second DAA based regimen. Bayesian network (BN) learning on HCV sequence data from patients treated with DAAs could provide insight in resistance pathways against PIs for HCV subtypes 1a and 1b, in a similar way as applied before for HIV. The publicly available 'Rega-BN' tool chain was developed to study associative analyses for various pathogens. Our first analysis, comparing sequences from PI-naïve and PI-experienced patients, determined that NS3 substitutions R155K and V36M arise with PI-exposure in HCV1a infected patients, and were defined as major and minor resistance-associated variants respectively. NS3 variant 174H was newly identified as potentially related to PI resistance. In a second analysis, NS3 sequences from PI-naïve patients who cleared the virus during PI therapy and from PI-naïve patients who failed PI therapy were compared, showing that NS3 baseline variant 67S predisposes to treatment-failure and variant 72I to treatment success. This approach has the potential to better characterize the role of more RAVs, if sufficient therapy annotated sequence data becomes available in curated public databases. In addition, polymorphisms present in baseline sequences that predispose patients to therapy failure can be identified using this approach. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Comparative molecular dynamics simulation of Hepatitis C Virus NS3/4A protease (Genotypes 1b, 3a and 4b predicts conformational instability of the catalytic triad in drug resistant strains.

    Directory of Open Access Journals (Sweden)

    Mitchell Kramer

    Full Text Available The protease domain of the Hepatitis C Virus (HCV nonstructural protein 3 (NS3 has been targeted for inhibition by several direct-acting antiviral drugs. This approach has had marked success to treat infections caused by HCV genotype 1 predominant in the USA, Europe, and Japan. However, genotypes 3 and 4, dominant in developing countries, are resistant to a number of these drugs and little progress has been made towards understanding the structural basis of their drug resistivity. We have previously developed a 4D computational methodology, based on 3D structure modeling and molecular dynamics simulation, to analyze the active sites of the NS3 proteases of HCV-1b and 4a in relation to their catalytic activity and drug susceptibility. Here, we improved the methodology, extended the analysis to include genotype 3a (predominant in South Asia including Pakistan, and compared the results of the three genotypes (1b, 3a and 4a. The 4D analyses of the interactions between the catalytic triad residues (His57, Asp81, and Ser139 indicate conformational instability of the catalytic site in HCV-3a and 4a compared to that of HCV-1b NS3 protease. The divergence is gradual and genotype-dependent, with HCV-1b being the most stable, HCV-4a being the most unstable and HCV-3a representing an intermediate state. These results suggest that the structural dynamics behavior, more than the rigid structure, could be related to the altered catalytic activity and drug susceptibility seen in NS3 proteases of HCV-3a and 4a.

  20. Comparative Molecular Dynamics Simulation of Hepatitis C Virus NS3/4A Protease (Genotypes 1b, 3a and 4a) Predicts Conformational Instability of the Catalytic Triad in Drug Resistant Strains

    Science.gov (United States)

    Kramer, Mitchell; Halleran, Daniel; Rahman, Moazur; Iqbal, Mazhar; Anwar, Muhammad Ikram; Sabet, Salwa; Ackad, Edward; Yousef, Mohammad

    2014-01-01

    The protease domain of the Hepatitis C Virus (HCV) nonstructural protein 3 (NS3) has been targeted for inhibition by several direct-acting antiviral drugs. This approach has had marked success to treat infections caused by HCV genotype 1 predominant in the USA, Europe, and Japan. However, genotypes 3 and 4, dominant in developing countries, are resistant to a number of these drugs and little progress has been made towards understanding the structural basis of their drug resistivity. We have previously developed a 4D computational methodology, based on 3D structure modeling and molecular dynamics simulation, to analyze the active sites of the NS3 proteases of HCV-1b and 4a in relation to their catalytic activity and drug susceptibility. Here, we improved the methodology, extended the analysis to include genotype 3a (predominant in South Asia including Pakistan), and compared the results of the three genotypes (1b, 3a and 4a). The 4D analyses of the interactions between the catalytic triad residues (His57, Asp81, and Ser139) indicate conformational instability of the catalytic site in HCV-3a and 4a compared to that of HCV-1b NS3 protease. The divergence is gradual and genotype-dependent, with HCV-1b being the most stable, HCV-4a being the most unstable and HCV-3a representing an intermediate state. These results suggest that the structural dynamics behavior, more than the rigid structure, could be related to the altered catalytic activity and drug susceptibility seen in NS3 proteases of HCV-3a and 4a. PMID:25111232

  1. Prevalence of Resistance-Associated Substitutions in HCV NS5A, NS5B, or NS3 and Outcomes of Treatment With Ledipasvir and Sofosbuvir.

    Science.gov (United States)

    Sarrazin, Christoph; Dvory-Sobol, Hadas; Svarovskaia, Evguenia S; Doehle, Brian P; Pang, Phillip S; Chuang, Shu-Min; Ma, Julie; Ding, Xiao; Afdhal, Nezam H; Kowdley, Kris V; Gane, Edward J; Lawitz, Eric; Brainard, Diana M; McHutchison, John G; Miller, Michael D; Mo, Hongmei

    2016-09-01

    We evaluated the effects of baseline hepatitis C virus (HCV) NS5A, NS5B, and NS3 resistance-associated substitutions (RASs) on response to the combination of ledipasvir and sofosbuvir, with or without ribavirin, in patients with HCV genotype 1 infection. We analyzed data from 2144 participants in phase 2 and 3 studies of patients with HCV genotype 1a or b infection who received the combination of ledipasvir (90 mg) and sofosbuvir (400 mg) (ledipasvir/sofosbuvir) once daily, with or without ribavirin twice daily. Population and/or deep sequence analyses of the HCV NS3, NS5A, and NS5B genes were performed on blood samples collected at baseline. Overall, 16.0% of patients had detectable baseline RASs in NS5A. Among patients with HCV genotype 1b infection, there was no significant effect of baseline RASs in NS5A on sustained viral response 12 weeks after the end of treatment (SVR12) with ledipasvir/sofosbuvir and only a small effect in patients with HCV genotype 1a infection. RASs in NS5A that increased the half-maximal effective concentration to ledipasvir by more than 100-fold reduced the rate of SVR12 in treatment-naive patients given ledipasvir/sofosbuvir for 8 weeks (P = .011), but not for 12 weeks. These same baseline NS5A RASs reduced the percentage of treatment-experienced patients who achieved an SVR12 to 12 weeks (but not 24 weeks) ledipasvir/sofosbuvir (P ledipasvir/sofosbuvir in combination with ribavirin for 12 weeks. Overall, 2.5% of patients had baseline NS5B nucleotide inhibitor RASs (L159F, N142T, S282G, or L320S) and all achieved an SVR12. Of patients previously treated with protease inhibitors, 53.7% had RASs in NS3 and 96.5% achieved an SVR12. Baseline RASs in NS5A have minimal effects on patient responses to ledipasvir/sofosbuvir therapy. When these RASs do have effects, they could be largely overcome by extending treatment duration or through treatment intensification. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights

  2. Antiviral Activity and Resistance Analysis of NS3/4A Protease Inhibitor Grazoprevir and NS5A Inhibitor Elbasvir in Hepatitis C Virus GT4 Replicons.

    Science.gov (United States)

    Asante-Appiah, Ernest; Curry, Stephanie; McMonagle, Patricia; Ingravallo, Paul; Chase, Robert; Nickle, David; Qiu, Ping; Howe, Anita; Lahser, Frederick C

    2017-07-01

    Although genotype 4 (GT4)-infected patients represent a minor overall percentage of the global hepatitis C virus (HCV)-infected population, the high prevalence of the genotype in specific geographic regions coupled with substantial sequence diversity makes it an important genotype to study for antiviral drug discovery and development. We evaluated two direct-acting antiviral agents-grazoprevir, an HCV NS3/4A protease inhibitor, and elbasvir, an HCV NS5A inhibitor-in GT4 replicons prior to clinical studies in this genotype. Following a bioinformatics analysis of available GT4 sequences, a set of replicons bearing representative GT4 clinical isolates was generated. For grazoprevir, the 50% effective concentration (EC50) against the replicon bearing the reference GT4a (ED43) NS3 protease and NS4A was 0.7 nM. The median EC50 for grazoprevir against chimeric replicons encoding NS3/4A sequences from GT4 clinical isolates was 0.2 nM (range, 0.11 to 0.33 nM; n = 5). The difficulty in establishing replicons bearing NS3/4A resistance-associated substitutions was substantially overcome with the identification of a G162R adaptive substitution in NS3. Single NS3 substitutions D168A/V identified from de novo resistance selection studies reduced grazoprevir antiviral activity by 137- and 47-fold, respectively, in the background of the G162R replicon. For elbasvir, the EC50 against the replicon bearing the reference full-length GT4a (ED43) NS5A gene was 0.0002 nM. The median EC50 for elbasvir against chimeric replicons bearing clinical isolates from GT4 was 0.0007 nM (range, 0.0002 to 34 nM; n = 14). De novo resistance selection studies in GT4 demonstrated a high propensity to suppress the emergence of amino acid substitutions that confer high-potency reductions to elbasvir. Phenotypic characterization of the NS5A amino acid substitutions identified (L30F, L30S, M31V, and Y93H) indicated that they conferred 15-, 4-, 2.5-, and 7.5-fold potency losses, respectively, to elbasvir. The

  3. Computer Aided Screening of Phytochemicals from Garcinia against the Dengue NS2B/NS3 Protease.

    Science.gov (United States)

    Qamar, Tahir Ul; Mumtaz, Arooj; Ashfaq, Usman Ali; Azhar, Samia; Fatima, Tabeer; Hassan, Muhammad; Hussain, Syed Sajid; Akram, Waheed; Idrees, Sobia

    2014-01-01

    Dengue virus NS2/NS3 protease because of its ability to cleave viral proteins is considered as an attractive target to screen antiviral agents. Medicinal plants contain a variety of phytochemicals that can be used as drug against different diseases and infections. Therefore, this study was designed to uncover possible phytochemical of different classes (Aromatic, Carbohydrates, Lignin, Saponins, Steroids, Tannins, Terpenoids, Xanthones) that could be used as inhibitors against the NS2B/NS3 protease of DENV. With the help of molecular docking, Garcinia phytochemicals found to be bound deeply inside the active site of DENV NS2B/NS3 protease among all tested phytochemicals and had interactions with catalytic triad (His51, Asp75, Ser135). Thus, it can be concluded from the study that these Gracinia phytochemicals could serve as important inhibitors to inhibit the viral replication inside the host cell. Further in-vitro investigations require confirming their efficacy.

  4. [Construction of point mutation plasmids expressing HCV NS3/4A with different secondary structures at amino-terminal and their expressions in Huh 7 cells].

    Science.gov (United States)

    Wang, Xue-ping; Li, Fu-jun; Motoko, Nagano-fujii; Kikumi, Kitayama; Hotta, Hak

    2009-04-01

    To construct point mutation plasmids expressing HCV NS3/4A with different secondary structures at amino-terminal, and express the constructs in Huh 7 cells. Using pSG5/M-H05-5/4A as the template (A1-1) and primers designed according to the typing criteria, 4 single point mutation plasmids, namely pSG5/M-H05-5(A1-2)/4A(A1-2) (Y56F), pSG5/M-H05-5(B1-1)/4A(B1-1) (L80Q), pSG5/M-H05-5(B2-1)/4A(B2-1) (V51A), and pSG5/M-H05-5(B2-2)/4A(B2-2) (S61A), were constructed. With A1-2, B2-1, and B2-2 as the templates, the leucine to glutamine mutation at position 80 (L80Q) was induced to construct another 3 double point mutation plasmids pSG5/M-H05-5(B1-2)/4A(B1-2), pSG5/M-H05-5(A2-1)/4A(A2-1), and pSG5/M-H05-5(A2-2)/4A(A2-2), respectively. DNA sequencing was performed for confirmation of the mutations. Huh 7 cells were transfected with the constructs using FuGene 6 transfection reagents. Indirect immunofluorescence staining and Western blotting were used to detect the expression of the constructs. Indirect immunofluorescence assay revealed 4 subcellular localization patterns of NS3 protein, including dot-like staining, diffuse staining, doughnut-like staining, and rod-shape staining. Western blotting also demonstrated successful expression of the constructs and weak in cis and in trans NS3 serine protease activities of subtypes A2-1 and B2-1 in comparison with other subtypes. The point mutation plasmids expressing HCV NS3/4A with different secondary structures at amino-terminal are constructed successfully, which provides the basis for further study of different subtypes of HCV.

  5. Substitutions at NS3 Residue 155, 156, or 168 of Hepatitis C Virus Genotypes 2 to 6 Induce Complex Patterns of Protease Inhibitor Resistance

    DEFF Research Database (Denmark)

    Jensen, Sanne B.; Serre, Stephanie B. N.; Humes, Daryl G.

    2015-01-01

    Various protease inhibitors (PIs) are currently becoming available for treatment of hepatitis C virus (HCV). For genotype 1, substitutions at NS3 protease positions 155, 156, and 168 are main determinants of PI resistance. For other genotypes, similar substitutions were selected during PI treatment...... to nine PIs (telaprevir, boceprevir, simeprevir, asunaprevir, vaniprevir, faldaprevir, paritaprevir, deldeprevir, and grazoprevir) in Huh7.5 cells. We found that most variants showed decreased fitness compared to original viruses. Overall, R155K-, A156G/S-, and D/Q168A/E/H/N/V-variants showed highest...... resistant. For the remaining PIs, most genotype 2-, 4-, 5-, and 6-, but not genotype 3-variants, showed varying resistance levels. Overall, grazoprevir (MK-5172) had the highest efficacy against original viruses and variants.This is the first comprehensive study revealing the impact of described key PI...

  6. Discovery and Early Clinical Evaluation of BMS-605339, a Potent and Orally Efficacious Tripeptidic Acylsulfonamide NS3 Protease Inhibitor for the Treatment of Hepatitis C Virus Infection

    Energy Technology Data Exchange (ETDEWEB)

    Scola, Paul M.; Wang, Alan Xiangdong; Good, Andrew C.; Sun, Li-Qiang; Combrink, Keith D.; Campbell, Jeffrey A.; Chen, Jie; Tu, Yong; Sin, Ny; Venables, Brian L.; Sit, Sing-Yuen; Chen, Yan; Cocuzza, Anthony; Bilder, Donna M.; D’Andrea, Stanley; Zheng, Barbara; Hewawasam, Piyasena; Ding, Min; Thuring, Jan; Li, Jianqing; Hernandez, Dennis; Yu, Fei; Falk, Paul; Zhai, Guangzhi; Sheaffer, Amy K.; Chen, Chaoqun; Lee, Min S.; Barry, Diana; Knipe, Jay O.; Li, Wenying; Han, Yong-Hae; Jenkins, Susan; Gesenberg, Christoph; Gao, Qi; Sinz, Michael W.; Santone, Kenneth S.; Zvyaga, Tatyana; Rajamani, Ramkumar; Klei, Herbert E.; Colonno, Richard J.; Grasela, Dennis M.; Hughes, Eric; Chien, Caly; Adams, Stephen; Levesque, Paul C.; Li, Danshi; Zhu, Jialong; Meanwell, Nicholas A.; McPhee, Fiona

    2014-03-13

    The discovery of BMS-605339 (35), a tripeptidic inhibitor of the NS3/4A enzyme, is described. This compound incorporates a cyclopropylacylsulfonamide moiety that was designed to improve the potency of carboxylic acid prototypes through the introduction of favorable nonbonding interactions within the S1' site of the protease. The identification of 35 was enabled through the optimization and balance of critical properties including potency and pharmacokinetics (PK). This was achieved through modulation of the P2* subsite of the inhibitor which identified the isoquinoline ring system as a key template for improving PK properties with further optimization achieved through functionalization. A methoxy moiety at the C6 position of this isoquinoline ring system proved to be optimal with respect to potency and PK, thus providing the clinical compound 35 which demonstrated antiviral activity in HCV-infected patients.

  7. Cloning and expression of NS3 helicase fragment of hepatitis C virus and the study of its immunoreactivity in HCV infected patients

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    Mahrou Sadri

    2015-02-01

    Full Text Available Objective(s: Hepatitis C is a major cause of liver failure worldwide. Current therapies applied for this disease are not fully effective and produce side effects in most cases. Non-structural protein 3 helicase (NS3 of HCV is one of the key enzymes in viral replication and infection. Therefore, this region is a promising target to design new drugs and therapies against HCV infection. The aim of this study was cloning and expression of HCV NS3 helicase fragment in Escherichia coli BL21 (DE3 using pET102/D-TOPO expression vector and studying immunoreactivity of the expressed antigen in Iranian infected with hepatitis C. Materials and Methods: The viral RNA was extracted from the serum of HCV infected patient. The NS3 helicase region was amplified by RT-PCR. The PCR product was directionally cloned into the expression vector pET102/D-TOPO and transformed into the BL21 strain of E. coli (DE3. The transformed bacteria were then induced by adding 1mM isopropyl-β-D-thiogalactopyranoside (IPTG into the culture medium to enhance the protein expression. SDS-PAGE and western blotting were carried out to identify the protein under investigation, and finally purified recombinant fusion protein was used as the antigen for ELISA method. Results: Theinsertion of theDNA fragment of the NS3 regioninto the expression vectorwas further confirmed by PCR and sequencing. SDS-PAGE analysis showed the successful expression of the recombinant protein of interest. Furthermore, immunoreactivity of fusion NS3 helicase was confirmed by ELISA and western blotting. Conclusion: It seems that this recombinant protein could be a useful source of antigen for future studies on HCV diagnosis and therapy.

  8. Further theoretical insight into the reaction mechanism of the hepatitis C NS3/NS4A serine protease

    Science.gov (United States)

    Martínez-González, José Ángel; Rodríguez, Alex; Puyuelo, María Pilar; González, Miguel; Martínez, Rodrigo

    2015-01-01

    The main reactions of the hepatitis C virus NS3/NS4A serine protease are studied using the second-order Møller-Plesset ab initio method and rather large basis sets to correct the previously reported AM1/CHARMM22 potential energy surfaces. The reaction efficiencies measured for the different substrates are explained in terms of the tetrahedral intermediate formation step (the rate-limiting process). The energies of the barrier and the corresponding intermediate are so close that the possibility of a concerted mechanism is open (especially for the NS5A/5B substrate). This is in contrast to the suggested general reaction mechanism of serine proteases, where a two-step mechanism is postulated.

  9. Natural Polymorphisms Conferring Resistance to HCV Protease and Polymerase Inhibitors in Treatment-Naïve HIV/HCV Co-Infected Patients in China.

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    Kali Zhou

    Full Text Available The advent of direct-acting agents (DAAs has improved treatment of HCV in HIV co-infection, but may be limited by primary drug resistance. This study reports the prevalence of natural polymorphisms conferring resistance to NS3/4A protease inhibitors and NS5B polymerase inhibitors in treatment-naïve HIV/HCV co-infected individuals in China.Population based NS3/4A sequencing was completed for 778 treatment-naïve HIV/HCV co-infected patients from twelve provinces. NS3 sequences were amplified by nested PCR using in-house primers for genotypes 1-6. NS5B sequencing was completed for genotyping in 350 sequences. Resistance-associated variants (RAVs were identified in positions associated with HCV resistance.Overall, 72.8% (566/778 of all HCV sequences had at least one RAV associated with HCV NS3/4A protease inhibitor resistance. Variants were found in 3.6% (7/193 of genotype 1, 100% (23/23 of genotype 2, 100% (237/237 of genotype 3 and 92% (299/325 of genotype 6 sequences. The Q80K variant was present in 98.4% of genotype 6a sequences. High-level RAVs were rare, occurring in only 0.8% of patients. 93% (64/69 patients with genotype 1b also carried the C316N variant associated with NS5B low-level resistance.The low frequency of high-level RAVs associated with primary HCV DAA resistance among all genotypes in HIV/HCV co-infected patients is encouraging. Further phenotypic studies and clinical research are needed.

  10. Immunogenicity of Multi-Epitope DNA and Peptide Vaccine Candidates Based on Core, E2, NS3 and NS5B HCV Epitopes in BALB/c Mice.

    Science.gov (United States)

    Pishraft Sabet, Leila; Taheri, Tahereh; Memarnejadian, Arash; Mokhtari Azad, Talat; Asgari, Fatemeh; Rahimnia, Ramin; Alavian, Seyed Moayed; Rafati, Sima; Samimi Rad, Katayoun

    2014-10-01

    Hypervariability of HCV proteins is an important obstacle to design an efficient vaccine for HCV infection. Multi-epitope vaccines containing conserved epitopes of the virus could be a promising approach for protection against HCV. Cellular and humoral immune responses against multi-epitope DNA and peptide vaccines were evaluated in BALB/c mice. In this experimental study, multi-epitope DNA- and peptide-based vaccines for HCV infection harboring immunodominant CD8+ T cell epitopes (HLA-A2 and H2-Dd) from Core (132-142), NS3 (1073-1081) and NS5B (2727-2735), a Th CD4+ epitope from NS3 (1248-1262) and a B-cell epitope from E2 (412-426) were designed. Multi-epitope DNA and peptide vaccines were tested in two regimens as heterologous DNA/peptide (group 1) and homologous peptide/peptide (group 2) prime/boost vaccine in BALB/c mice model. Electroporation was used for delivery of the DNA vaccine. Peptide vaccine was formulated with Montanide ISA 720 (M720) as adjuvant. Cytokine assay and antibody detection were performed to analyze the immune responses. Mice immunized with multi-epitope peptide formulated with M720 developed higher HCV-specific levels of total IgG, IgG1 and IgG2a than those immunized with multi-epitope DNA vaccine. IFN-γ levels in group 2 were significantly higher than group 1 (i.e. 3 weeks after the last immunization; 37.61 ± 2.39 vs. 14.43 ± 0.43, P epitope DNA and peptide-vaccines confirmed their specific immunogenicity in BALB/c mice. However, lower Th1 immune responses in mice immunized with DNA vaccine suggests further investigations to improve the immunogenicity of the multi-epitope DNA vaccine through immune enhancers.

  11. The prevalence of the pre-existing hepatitis C viral variants and the evolution of drug resistance in patients treated with the NS3-4a serine protease inhibitor telaprevir

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Libin [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory; Perelson, Alan S [Los Alamos National Laboratory

    2008-01-01

    Telaprevir (VX-950), a novel hepatitis C virus (HCV) NS3-4A serine protease inhibitor, has demonstrated substantial antiviral activity in patients infected with HCV genotype 1. Some patients experience viral breakthrough, which has been shown to be associated with emergence of telaprevir-resistant HCV variants during treatment. The exact mechanisms underlying the rapid selection of drug resistant viral variants during dosing are not fully understood. In this paper, we develop a two-strain model to study the pre-treatment prevalence of the mutant virus and derive an analytical solution of the mutant frequency after administration of the protease inhibitor. Our analysis suggests that the rapid increase of the mutant frequency during therapy is not due to mutant growth but rather due to the rapid and profound loss of wild-type virus, which uncovers the pre-existing mutant variants. We examine the effects of backward mutation and hepatocyte proliferation on the pre-existence of the mutant virus and the competition between wild-type and drug resistant virus during therapy. We then extend the simple model to a general model with multiple viral strains. Mutations during therapy do not play a significant role in the dynamics of various viral strains, although they are capable of generating low levels of HCV variants that would otherwise be completely suppressed because of fitness disadvantages. Hepatocyte proliferation may not affect the pretreatment frequency of mutant variants, but is able to influence the quasispecies dynamics during therapy. It is the relative fitness of each mutant strain compared with wild-type that determines which strain(s) will dominate the virus population. The study provides a theoretical framework for exploring the prevalence of pre-existing mutant variants and the evolution of drug resistance during treatment with other protease inhibitors or HCV polymerase inhibitors.

  12. In Silico Screening, Alanine Mutation, and DFT Approaches for Identification of NS2B/NS3 Protease Inhibitors

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    R. Balajee

    2016-01-01

    Full Text Available To identify the ligand that binds to a target protein with high affinity is a nontrivial task in computer-assisted approaches. Antiviral drugs have been identified for NS2B/NS3 protease enzyme on the mechanism to cleave the viral protein using the computational tools. The consequence of the molecular docking, free energy calculations, and simulation protocols explores the better ligand. It provides in-depth structural insights with the catalytic triad of His51, Asp75, Ser135, and Gly133. The MD simulation was employed here to predict the stability of the complex. The alanine mutation has been performed and its stability was monitored by using the molecular dynamics simulation. The minimal RMSD value suggests that the derived complexes are close to equilibrium. The DFT outcome reveals that the HOMO-LUMO gap of Ligand19 is 2.86 kcal/mol. Among the considered ligands, Ligand19 shows the lowest gap and it is suggested that the HOMO of Ligand19 may transfer the electrons to the LUMO in the active regions. The calculated binding energy of Ligand19 using the DFT method is in good agreement with the docking studies. The pharmacological activity of ligand was performed and satisfies Lipinski rule of 5. Moreover, the computational results are compared with the available IC50 values of experimental results.

  13. In silico evaluation of inhibitory potential of triterpenoids from Azadirachta indica against therapeutic target of dengue virus, NS2B-NS3 protease.

    Science.gov (United States)

    Dwivedi, Vivek Dhar; Tripathi, Indra Prasad; Mishra, Sarad Kumar

    2016-01-01

    NS2B-NS3 protease (NS2B-NS3 pro ) of dengue virus (DENV) is the prime therapeutic target for the development of anti-dengue drug to combat the DENV infection, which is currently an increasing health problem in many countries. In the area of antiviral drug discovery, numerous reports on the antiviral activity of various medicinal plants against dengue viruses have been published. Neem plant (Azadirachta indica) is one among those medicinal plants which is reported to show potential antiviral activity against DENV. But active principle of neem plant extract which has inhibitory potential against DENV NS2B-NS3 pro is not yet reported. The aim of the present study was to explore the inhibitory potential of five triterpenoids from neem plant, viz. nimbin, desacetylnimbin, desacetylsalannin, azadirachtin and salannin, against DENV NS2B-NS3 pro. The molecular 3D structural data of DENV NS2B-NS3 pro and selected triterpenoids of neem plant were collected from protein databank (PDB ID: 2VBC) and PubChem database respectively. The molecular docking approach was employed to find out the in silico inhibitory potential of the five triterpenoids against DENV NS2B- NS3 pro. The molecular docking results showed that nimbin, desacetylnimbin and desacetylsalannin have good binding affinity with DENV NS2B-NS3 pro , while azadirachtin and salannin did not show any interaction with the target protein. It was observed that the DENV NS2B-NS3 pro binding energy for nimbin, desacetylnimbin and desacetylsalannin were -5.56, -5.24 and -3.43 kcal/mol, respectively. The findings attained through this study on the molecular interaction mode of three neem triterpenoids and DENV NS2B-NS3 pro can be considered for further in vitro and in vivo validation for designing new potential drugs for DENV infection.

  14. In Vitro Evaluation of Novel Inhibitors against the NS2B-NS3 Protease of Dengue Fever Virus Type 4

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    Thi Thanh Hanh Nguyen

    2013-12-01

    Full Text Available The discovery of potent therapeutic compounds against dengue virus is urgently needed. The NS2B-NS3 protease (NS2B-NS3pro of dengue fever virus carries out all enzymatic activities needed for polyprotein processing and is considered to be amenable to antiviral inhibition by analogy. Virtual screening of 300,000 compounds using Autodock 3 on the GVSS platform was conducted to identify novel inhibitors against the NS2B-NS3pro. Thirty-six compounds were selected for in vitro assay against NS2B-NS3pro expressed in Pichia pastoris. Seven novel compounds were identified as inhibitors with IC50 values of 3.9 ± 0.6–86.7 ± 3.6 μM. Three strong NS2B-NS3pro inhibitors were further confirmed as competitive inhibitors with Ki values of 4.0 ± 0.4, 4.9 ± 0.3, and 3.4 ± 0.1 μM, respectively. Hydrophobic and hydrogen bond interactions between amino acid residues in the NS3pro active site with inhibition compounds were also identified.

  15. Design, structure-based focusing and in silico screening of combinatorial library of peptidomimetic inhibitors of Dengue virus NS2B-NS3 protease

    Science.gov (United States)

    Frecer, Vladimir; Miertus, Stanislav

    2010-03-01

    Serine protease activity of the NS3 protein of Dengue virus is an important target of antiviral agents that interfere with the viral polyprotein precursor processing catalyzed by the NS3 protease (NS3pro), which is important for the viral replication and maturation. Recent studies showed that substrate-based peptidomimetics carrying an electrophilic warhead inhibit the NS2B-NS3pro cofactor-protease complex with inhibition constants in the low micromolar concentration range when basic amino acid residues occupy P1 and P2 positions of the inhibitor, and an aldehyde warhead is attached to the P1. We have used computer-assisted combinatorial techniques to design, focus using the NS2B-NS3pro receptor 3D structure, and in silico screen a virtual library of more than 9,200 peptidomimetic analogs targeted around the template inhibitor Bz-Nle-Lys-Arg-Arg- H (Bz—benzoyl) that are composed mainly of unusual amino acid residues in all positions P1-P4. The most promising virtual hits were analyzed in terms of computed enzyme-inhibitor interactions and Adsorption, Distribution, Metabolism and Excretion (ADME) related physico-chemical properties. Our study can direct the interest of medicinal chemists working on a next generation of antiviral chemotherapeutics against the Dengue Fever towards the explored subset of the chemical space that is predicted to contain peptide aldehydes with NS3pro inhibition potencies in nanomolar range which display ADME-related properties comparable to the training set inhibitors.

  16. Characterization of the Zika virus two-component NS2B-NS3 protease and structure-assisted identification of allosteric small-molecule antagonists.

    Science.gov (United States)

    Shiryaev, Sergey A; Farhy, Chen; Pinto, Antonella; Huang, Chun-Teng; Simonetti, Nicole; Ngono, Annie Elong; Dewing, Antimone; Shresta, Sujan; Pinkerton, Anthony B; Cieplak, Piotr; Strongin, Alex Y; Terskikh, Alexey V

    2017-07-01

    The recent re-emergence of Zika virus (ZIKV)1, a member of the Flaviviridae family, has become a global emergency. Currently, there are no effective methods of preventing or treating ZIKV infection, which causes severe neuroimmunopathology and is particularly harmful to the developing fetuses of infected pregnant women. However, the pathology induced by ZIKV is unique among flaviviruses, and knowledge of the biology of other family members cannot easily be extrapolated to ZIKV. Thus, structure-function studies of ZIKV proteins are urgently needed to facilitate the development of effective preventative and therapeutic agents. Like other flaviviruses, ZIKV expresses an NS2B-NS3 protease, which consists of the NS2B cofactor and the NS3 protease domain and is essential for cleavage of the ZIKV polyprotein precursor and generation of fully functional viral proteins. Here, we report the enzymatic characterization of ZIKV protease, and we identify structural scaffolds for allosteric small-molecule inhibitors of this protease. Molecular modeling of the protease-inhibitor complexes suggests that these compounds bind to the druggable cavity in the NS2B-NS3 protease interface and affect productive interactions of the protease domain with its cofactor. The most potent compound demonstrated efficient inhibition of ZIKV propagation in vitro in human fetal neural progenitor cells and in vivo in SJL mice. The inhibitory scaffolds could be further developed into valuable research reagents and, ultimately, provide a roadmap for the selection of efficient inhibitors of ZIKV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Virtual screening of commercial cyclic peptides as NS2B-NS3 protease inhibitor of dengue virus serotype 2 through molecular docking simulation

    Science.gov (United States)

    Nasution, M. A. F.; Aini, R. N.; Tambunan, U. S. F.

    2017-04-01

    A disease caused by dengue virus infection has become one of the major health problems in the world, particularly in Asia, Africa, and South America. This disease has become endemic in more than 100 countries, and approximately 100 million cases occur each year with 2.5 billion people or 40% of the world population at risk of having this virus infection. Therefore, we need an antiviral drug that can inhibit the activity of the enzymes that involved in the virus replication in the body. Lately, the peptide-based drug design has been developed and proved to have interesting pharmacological properties. This study uses commercially cyclic peptides that have already marketed. The purpose of this study is to screen the commercial cyclic peptides that can be used as an inhibitor of the NS2B-NS3 protease of dengue virus serotype 2 (DENV-2) through molecular docking simulations. Inhibition of NS3 protease enzyme can lead to enzymatic inhibition activity so the formed polyprotein from the translation of RNA cannot be cut into pieces and remain in the long strand form. Consequently, proteins that are vital for the sustainability of dengue virus replication cannot be formed. This research resulted in [alpha]-ANF (1-28), rat, Brain Natriuretic Peptide, porcine, Atrial Natriuretic Factor (3-28) (human) and Atrial Natriuretic Peptide (126-150) (rat) as the best drug candidate for inhibiting the NS2B-NS3 protease of DENV-2.

  18. Flexibility between the protease and helicase domains of the dengue virus NS3 protein conferred by the linker region and its functional implications.

    Science.gov (United States)

    Luo, Dahai; Wei, Na; Doan, Danny N; Paradkar, Prasad N; Chong, Yuwen; Davidson, Andrew D; Kotaka, Masayo; Lescar, Julien; Vasudevan, Subhash G

    2010-06-11

    The dengue virus (DENV) NS3 protein is essential for viral polyprotein processing and RNA replication. It contains an N-terminal serine protease region (residues 1-168) joined to an RNA helicase (residues 180-618) by an 11-amino acid linker (169-179). The structure at 3.15 A of the soluble NS3 protein from DENV4 covalently attached to 18 residues of the NS2B cofactor region (NS2B(18)NS3) revealed an elongated molecule with the protease domain abutting subdomains I and II of the helicase (Luo, D., Xu, T., Hunke, C., Grüber, G., Vasudevan, S. G., and Lescar, J. (2008) J. Virol. 82, 173-183). Unexpectedly, using similar crystal growth conditions, we observed an alternative conformation where the protease domain has rotated by approximately 161 degrees with respect to the helicase domain. We report this new crystal structure bound to ADP-Mn(2+) refined to a resolution of 2.2 A. The biological significance for interdomain flexibility conferred by the linker region was probed by either inserting a Gly residue between Glu(173) and Pro(174) or replacing Pro(174) with a Gly residue. Both mutations resulted in significantly lower ATPase and helicase activities. We next increased flexibility in the linker by introducing a Pro(176) to Gly mutation in a DENV2 replicon system. A 70% reduction in luciferase reporter signal and a similar reduction in the level of viral RNA synthesis were observed. Our results indicate that the linker region has evolved to an optimum length to confer flexibility to the NS3 protein that is required both for polyprotein processing and RNA replication.

  19. NMR analysis of the dynamic exchange of the NS2B cofactor between open and closed conformations of the West Nile virus NS2B-NS3 protease.

    Directory of Open Access Journals (Sweden)

    Xun-Cheng Su

    Full Text Available BACKGROUND: The two-component NS2B-NS3 proteases of West Nile and dengue viruses are essential for viral replication and established targets for drug development. In all crystal structures of the proteases to date, the NS2B cofactor is located far from the substrate binding site (open conformation in the absence of inhibitor and lining the substrate binding site (closed conformation in the presence of an inhibitor. METHODS: In this work, nuclear magnetic resonance (NMR spectroscopy of isotope and spin-labeled samples of the West Nile virus protease was used to investigate the occurrence of equilibria between open and closed conformations in solution. FINDINGS: In solution, the closed form of the West Nile virus protease is the predominant conformation irrespective of the presence or absence of inhibitors. Nonetheless, dissociation of the C-terminal part of the NS2B cofactor from the NS3 protease (open conformation occurs in both the presence and the absence of inhibitors. Low-molecular-weight inhibitors can shift the conformational exchange equilibria so that over 90% of the West Nile virus protease molecules assume the closed conformation. The West Nile virus protease differs from the dengue virus protease, where the open conformation is the predominant form in the absence of inhibitors. CONCLUSION: Partial dissociation of NS2B from NS3 has implications for the way in which the NS3 protease can be positioned with respect to the host cell membrane when NS2B is membrane associated via N- and C-terminal segments present in the polyprotein. In the case of the West Nile virus protease, discovery of low-molecular-weight inhibitors that act by breaking the association of the NS2B cofactor with the NS3 protease is impeded by the natural affinity of the cofactor to the NS3 protease. The same strategy can be more successful in the case of the dengue virus NS2B-NS3 protease.

  20. In-silico identification and evaluation of plant flavonoids as dengue NS2B/NS3 protease inhibitors using molecular docking and simulation approach.

    Science.gov (United States)

    Qamar, Muhammad Tahirul; Ashfaq, Usman Ali; Tusleem, Kishver; Mumtaz, Arooj; Tariq, Quratulain; Goheer, Alina; Ahmed, Bilal

    2017-11-01

    Dengue infection is prevailing among the people not only from the developing countries but also from the developed countries due to its high morbidity rate around the globe. Hence, due to the unavailability of any suitable vaccine for rigorous dengue virus (DENV), the only mode of its treatment is prevention. The circumstances require an urgent development of efficient and practical treatment to deal with these serotypes. The severe effects and cost of synthetic vaccines simulated researchers to find anti-viral agents from medicinal plants. Flavonoids present in medicinal plants, holds anti-viral activity and can be used as vaccine against viruses. Therefore, present study was planned to find anti-viral potential of 2500 flavonoids inhibitors against the DENVNS2B/NS3 protease through computational screening which can hinder the viral replication within the host cell. By using molecular docking, it was revealed that flavonoids showed strong and stable bonding in the binding pocket of DENV NS2B/NS3 protease and had strong interactions with catalytic triad. Drug capability and anti-dengue potential of the flavonoids was also evaluated by using different bioinformatics tools. Some flavonoids effectively blocked the catalytic triad of DENV NS2B/NS3 protease and also passed through drug ability evaluation. It can be concluded from this study that these flavonoids could act as potential inhibitors to stop the replication of DENV and there is a need to study the action of these molecules in-vitro to confirm their action and other properties.

  1. Computational study on the inhibitor binding mode and allosteric regulation mechanism in hepatitis C virus NS3/4A protein.

    Directory of Open Access Journals (Sweden)

    Weiwei Xue

    Full Text Available HCV NS3/4A protein is an attractive therapeutic target responsible for harboring serine protease and RNA helicase activities during the viral replication. Small molecules binding at the interface between the protease and helicase domains can stabilize the closed conformation of the protein and thus block the catalytic function of HCV NS3/4A protein via an allosteric regulation mechanism. But the detailed mechanism remains elusive. Here, we aimed to provide some insight into the inhibitor binding mode and allosteric regulation mechanism of HCV NS3/4A protein by using computational methods. Four simulation systems were investigated. They include: apo state of HCV NS3/4A protein, HCV NS3/4A protein in complex with an allosteric inhibitor and the truncated form of the above two systems. The molecular dynamics simulation results indicate HCV NS3/4A protein in complex with the allosteric inhibitor 4VA adopts a closed conformation (inactive state, while the truncated apo protein adopts an open conformation (active state. Further residue interaction network analysis suggests the communication of the domain-domain interface play an important role in the transition from closed to open conformation of HCV NS3/4A protein. However, the inhibitor stabilizes the closed conformation through interaction with several key residues from both the protease and helicase domains, including His57, Asp79, Asp81, Asp168, Met485, Cys525 and Asp527, which blocks the information communication between the functional domains interface. Finally, a dynamic model about the allosteric regulation and conformational changes of HCV NS3/4A protein was proposed and could provide fundamental insights into the allosteric mechanism of HCV NS3/4A protein function regulation and design of new potent inhibitors.

  2. Tracking HCV protease population diversity during transmission and susceptibility of founder populations to antiviral therapy.

    Science.gov (United States)

    Khera, Tanvi; Todt, Daniel; Vercauteren, Koen; McClure, C Patrick; Verhoye, Lieven; Farhoudi, Ali; Bhuju, Sabin; Geffers, Robert; Baumert, Thomas F; Steinmann, Eike; Meuleman, Philip; Pietschmann, Thomas; Brown, Richard J P

    2017-03-01

    Due to the highly restricted species-tropism of Hepatitis C virus (HCV) a limited number of animal models exist for pre-clinical evaluation of vaccines and antiviral compounds. The human-liver chimeric mouse model allows heterologous challenge with clinically relevant strains derived from patients. However, to date, the transmission and longitudinal evolution of founder viral populations in this model have not been characterized in-depth using state-of-the-art sequencing technologies. Focusing on NS3 protease encoding region of the viral genome, mutant spectra in a donor inoculum and individual recipient mice were determined via Illumina sequencing and compared, to determine the effects of transmission on founder viral population complexity. In all transmissions, a genetic bottleneck was observed, although diverse viral populations were transmitted in each case. A low frequency cloud of mutations ( 1% restricted to a subset of nucleotides. The population of SNVs >1% was reduced upon transmission while the low frequency SNV cloud remained stable. Fixation of multiple identical synonymous substitutions was apparent in independent transmissions, and no evidence for reversion of T-cell epitopes was observed. In addition, susceptibility of founder populations to antiviral therapy was assessed. Animals were treated with protease inhibitor (PI) monotherapy to track resistance associated substitution (RAS) emergence. Longitudinal analyses revealed a decline in population diversity under therapy, with no detectable RAS >1% prior to therapy commencement. Despite inoculation from a common source and identical therapeutic regimens, unique RAS emergence profiles were identified in different hosts prior to and during therapeutic failure, with complex mutational signatures at protease residues 155, 156 and 168 detected. Together these analyses track viral population complexity at high-resolution in the human-liver chimeric mouse model post-transmission and under therapeutic

  3. Discovery of (1R,5S)-N-[3-Amino-1-(cyclobutylmethyl)-2,3-dioxopropyl]- 3-[2(S)-[[[(1,1-dimethylethyl)amino]carbonyl]amino]-3,3-dimethyl-1-oxobutyl]- 6,6-dimethyl-3-azabicyclo[3.1.0]hexan-2(S)-carboxamide (SCH 503034), a Selective, Potent, Orally Bioavailable Hepatitis C Virus NS3 Protease Inhibitor: A Potential Therapeutic Agent for the Treatment of Hepatitis C Infection

    Energy Technology Data Exchange (ETDEWEB)

    Venkatraman, Srikanth; Bogen, Stephane L.; Arasappan, Ashok; Bennett, Frank; Chen, Kevin; Jao, Edwin; Liu, Yi-Tsung; Lovey, Raymond; Hendrata, Siska; Huang, Yuhua; Pan, Weidong; Parekh, Tejal; Pinto, Patrick; Popov, Veljko; Pike, Russel; Ruan, Sumei; Santhanam, Bama; Vibulbhan, Bancha; Wu, Wanli; Yang, Weiying; Kong, Jianshe; Liang, Xiang; Wong, Jesse; Liu, Rong; Butkiewicz, Nancy; Chase, Robert; Hart, Andrea; Agrawal, Sony; Ingravallo, Paul; Pichardo, John; Kong, Rong; Baroudy, Bahige; Malcolm, Bruce; Guo, Zhuyan; Prongay, Andrew; Madison, Vincent; Broske, Lisa; Cui, Xiaoming; Cheng, Kuo-Chi; Hsieh, Yunsheng; Brisson, Jean-Marc; Prelusky, Danial; Korfmacher, Walter; White, Ronald; Bogdanowich-Knipp, Susan; Pavlovsky, Anastasia; Bradley, Prudence; Saksena, Anil K.; Ganguly, Ashit; Piwinski, John; Girijavallabhan, Viyyoor; Njoroge, F. George (SPRI)

    2008-06-30

    Hepatitis C virus (HCV) infection is the major cause of chronic liver disease, leading to cirrhosis and hepatocellular carcinoma, which affects more than 170 million people worldwide. Currently the only therapeutic regimens are subcutaneous interferon-{alpha} or polyethylene glycol (PEG)-interferon-{alpha} alone or in combination with oral ribavirin. Although combination therapy is reasonably successful with the majority of genotypes, its efficacy against the predominant genotype (genotype 1) is moderate at best, with only about 40% of the patients showing sustained virological response. Herein, the SAR leading to the discovery of 70 (SCH 503034), a novel, potent, selective, orally bioavailable NS3 protease inhibitor that has been advanced to clinical trials in human beings for the treatment of hepatitis C viral infections is described. X-ray structure of inhibitor 70 complexed with the NS3 protease and biological data are also discussed.

  4. Discovery of (1R,5S)-N-[3-amino-1-(cyclobutylmethyl)-2,3-dioxopropyl]- 3-[2(S)-[[[(1,1-dimethylethyl)amino]carbonyl]amino]-3,3-dimethyl-1-oxobutyl]- 6,6-dimethyl-3-azabicyclo[3.1.0]hexan-2(S)-carboxamide (SCH 503034), a selective, potent, orally bioavailable hepatitis C virus NS3 protease inhibitor: a potential therapeutic agent for the treatment of hepatitis C infection.

    Science.gov (United States)

    Venkatraman, Srikanth; Bogen, Stéphane L; Arasappan, Ashok; Bennett, Frank; Chen, Kevin; Jao, Edwin; Liu, Yi-Tsung; Lovey, Raymond; Hendrata, Siska; Huang, Yuhua; Pan, Weidong; Parekh, Tejal; Pinto, Patrick; Popov, Veljko; Pike, Russel; Ruan, Sumei; Santhanam, Bama; Vibulbhan, Bancha; Wu, Wanli; Yang, Weiying; Kong, Jianshe; Liang, Xiang; Wong, Jesse; Liu, Rong; Butkiewicz, Nancy; Chase, Robert; Hart, Andrea; Agrawal, Sony; Ingravallo, Paul; Pichardo, John; Kong, Rong; Baroudy, Bahige; Malcolm, Bruce; Guo, Zhuyan; Prongay, Andrew; Madison, Vincent; Broske, Lisa; Cui, Xiaoming; Cheng, Kuo-Chi; Hsieh, Yunsheng; Brisson, Jean-Marc; Prelusky, Danial; Korfmacher, Walter; White, Ronald; Bogdanowich-Knipp, Susan; Pavlovsky, Anastasia; Bradley, Prudence; Saksena, Anil K; Ganguly, Ashit; Piwinski, John; Girijavallabhan, Viyyoor; Njoroge, F George

    2006-10-05

    Hepatitis C virus (HCV) infection is the major cause of chronic liver disease, leading to cirrhosis and hepatocellular carcinoma, which affects more than 170 million people worldwide. Currently the only therapeutic regimens are subcutaneous interferon-alpha or polyethylene glycol (PEG)-interferon-alpha alone or in combination with oral ribavirin. Although combination therapy is reasonably successful with the majority of genotypes, its efficacy against the predominant genotype (genotype 1) is moderate at best, with only about 40% of the patients showing sustained virological response. Herein, the SAR leading to the discovery of 70 (SCH 503034), a novel, potent, selective, orally bioavailable NS3 protease inhibitor that has been advanced to clinical trials in human beings for the treatment of hepatitis C viral infections is described. X-ray structure of inhibitor 70 complexed with the NS3 protease and biological data are also discussed.

  5. Hepatitis C virus NS2 and NS3/4A proteins are potent inhibitors of host cell cytokine/chemokine gene expression

    Directory of Open Access Journals (Sweden)

    Hiscott John

    2006-09-01

    Full Text Available Abstract Background Hepatitis C virus (HCV encodes several proteins that interfere with the host cell antiviral response. Previously, the serine protease NS3/4A was shown to inhibit IFN-β gene expression by blocking dsRNA-activated retinoic acid-inducible gene I (RIG-I and Toll-like receptor 3 (TLR3-mediated signaling pathways. Results In the present work, we systematically studied the effect of all HCV proteins on IFN gene expression. NS2 and NS3/4A inhibited IFN gene activation. NS3/4A inhibited the Sendai virus-induced expression of multiple IFN (IFN-α, IFN-β and IFN-λ1/IL-29 and chemokine (CCL5, CXCL8 and CXCL10 gene promoters. NS2 and NS3/4A, but not its proteolytically inactive form NS3/4A-S139A, were found to inhibit promoter activity induced by RIG-I or its adaptor protein Cardif (or IPS-1/MAVS/VISA. Both endogenous and transfected Cardif were proteolytically cleaved by NS3/4A but not by NS2 indicating different mechanisms of inhibition of host cell cytokine production by these HCV encoded proteases. Cardif also strongly colocalized with NS3/4A at the mitochondrial membrane, implicating the mitochondrial membrane as the site for proteolytic cleavage. In many experimental systems, IFN priming dramatically enhances RNA virus-induced IFN gene expression; pretreatment of HEK293 cells with IFN-α strongly enhanced RIG-I expression, but failed to protect Cardif from NS3/4A-mediated cleavage and failed to restore Sendai virus-induced IFN-β gene expression. Conclusion HCV NS2 and NS3/4A proteins were identified as potent inhibitors of cytokine gene expression suggesting an important role for HCV proteases in counteracting host cell antiviral response.

  6. Liver Fibrosis in HCV Monoinfected and HIV/HCV Coinfected Patients: Dysregulation of Matrix Metalloproteinases (MMPs) and Their Tissue Inhibitors TIMPs and Effect of HCV Protease Inhibitors.

    Science.gov (United States)

    Latronico, Tiziana; Mascia, Claudia; Pati, Ilaria; Zuccala, Paola; Mengoni, Fabio; Marocco, Raffaella; Tieghi, Tiziana; Belvisi, Valeria; Lichtner, Miriam; Vullo, Vincenzo; Mastroianni, Claudio Maria; Liuzzi, Grazia Maria

    2016-03-26

    An imbalance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) may contribute to liver fibrosis in patients with hepatitis C (HCV) infection. We measured the circulating levels of different MMPs and TIMPs in HCV monoinfected and HIV/HCV coinfected patients and evaluated the potential for anti-HCV therapy to modulate MMP and TIMP levels in HCV subjects. We analyzed 83 plasma samples from 16 HCV monoinfected patients undergoing dual or triple anti-HCV therapy, 15 HIV/HCV coinfected patients with undetectable HIV load, and 10 healthy donors (HD). Levels of MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10, TIMP-1, and TIMP-2 were measured by a SearchLight Multiplex Immunoassay Kit. MMP-2 and MMP-9 were the highest expressed MMPs among all the analyzed samples and their levels significantly increased in HCV monoinfected and HIV/HCV coinfected subjects compared to HD. TIMP-1 levels were significantly higher in HCV and HIV/HCV subjects compared to HD and were correlated with liver stiffness. These findings raise the possibility of using circulating TIMP-1 as a non-invasive marker of liver fibrosis in HCV infection. A longitudinal study demonstrated that MMP-9 levels significantly decreased (40% reduction from baseline) in patients receiving dual as well as triple direct-acting antivirals (DAA) anti-HCV therapy, which had no effect on MMP-2, TIMP-1, and TIMP-2. As the dysregulation of MMP-2 and MMP-9 may reflect inflammatory processes in the liver, the decrease of MMP-9 following HCV protease inhibitor treatment suggests a positive effect on the reduction of liver inflammation.

  7. Real-World Experiences with the Combination Treatment of Ledipasvir plus Sofosbuvir for 12 Weeks in HCV Genotype 1-Infected Japanese Patients: Achievement of a Sustained Virological Response in Previous Users of Peginterferon plus Ribavirin with HCV NS3/4A Inhibitors.

    Science.gov (United States)

    Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Suzuki, Eiichiro; Arai, Makoto; Ooka, Yoshihiko; Ogasawara, Sadahisa; Chiba, Tetsuhiro; Saito, Tomoko; Haga, Yuki; Takahashi, Koji; Sasaki, Reina; Wu, Shuang; Nakamoto, Shingo; Tawada, Akinobu; Maruyama, Hitoshi; Imazeki, Fumio; Kato, Naoya; Yokosuka, Osamu

    2017-04-25

    The aim of this study was to characterize the treatment response and serious adverse events of ledipasvir plus sofosbuvir therapies in Japanese patients infected with hepatitis C virus (HCV) genotype 1 (GT1). This retrospective study analyzed 240 Japanese HCV GT1 patients treated for 12 weeks with 90 mg of ledipasvir plus 400 mg of sofosbuvir daily. Sustained virological response at 12 weeks post-treatment (SVR12) was achieved in 236 of 240 (98.3%) patients. Among treatment-naïve patients, SVR12 was achieved in 136 of 138 (98.6%) patients, and among treatment-experienced patients, SVR12 was achieved in 100 of 102 (98.0%) patients. In patients previously treated with peginterferon plus ribavirin with various HCV NS3/4A inhibitors, 100% SVR rates (25/25) were achieved. Two relapsers had HCV NS5A resistance-associated variants (RAVs), but no HCV NS5B-S282 was observed after they relapsed. We experienced two patients with cardiac events during treatment. In conclusion, combination of ledipasvir plus sofosbuvir for 12 weeks is a potential therapy for HCV GT1 patients. Caution is needed for HCV NS5A RAVs, which were selected by HCV NS5A inhibitors and cardiac adverse events.

  8. Mutations Conferring Resistance to SCH6, a Novel Hepatitis C Virus NS3/4A Protease Inhibitor: Reduced DNA Replication Fitness and Partial Rescue by Second-Site Mutations

    Energy Technology Data Exchange (ETDEWEB)

    Yi, MinKyung; Tong, Xiao; Skelton, Angela; Chase, Robert; Chen, Tong; Prongay, Andrew; Bogen, Stephane L.; Saksena, Anil K.; Njoroge, F. George; Veselenak, Ronald L.; Pyles, Richard B.; Bourne, Nigel; Malcolm, Bruce A.; Lemon, Stanley M. (SPRI)

    2008-06-30

    Drug resistance is a major issue in the development and use of specific antiviral therapies. Here we report the isolation and characterization of hepatitis C virus RNA replicons resistant to a novel ketoamide inhibitor of the NS3/4A protease, SCH6 (originally SCH446211). Resistant replicon RNAs were generated by G418 selection in the presence of SCH6 in a dose-dependent fashion, with the emergence of resistance reduced at higher SCH6 concentrations. Sequencing demonstrated remarkable consistency in the mutations conferring SCH6 resistance in genotype 1b replicons derived from two different strains of hepatitis C virus, A156T/A156V and R109K. R109K, a novel mutation not reported previously to cause resistance to NS3/4A inhibitors, conferred moderate resistance only to SCH6. Structural analysis indicated that this reflects unique interactions of SCH6 with P{prime}-side residues in the protease active site. In contrast, A156T conferred high level resistance to SCH6 and a related ketoamide, SCH503034, as well as BILN 2061 and VX-950. Unlike R109K, which had minimal impact on NS3/4A enzymatic function, A156T significantly reduced NS3/4A catalytic efficiency, polyprotein processing, and replicon fitness. However, three separate second-site mutations, P89L, Q86R, and G162R, were capable of partially reversing A156T-associated defects in polyprotein processing and/or replicon fitness, without significantly reducing resistance to the protease inhibitor.

  9. Analysis of the Enzymatic Activity of an NS3 Helicase Genotype 3a Variant Sequence Obtained from a Relapse Patient.

    Directory of Open Access Journals (Sweden)

    Paola J S Provazzi

    Full Text Available The hepatitis C virus (HCV is a species of diverse genotypes that infect over 170 million people worldwide, causing chronic inflammation, cirrhosis and hepatocellular carcinoma. HCV genotype 3a is common in Brazil, and it is associated with a relatively poor response to current direct-acting antiviral therapies. The HCV NS3 protein cleaves part of the HCV polyprotein, and cellular antiviral proteins. It is therefore the target of several HCV drugs. In addition to its protease activity, NS3 is also an RNA helicase. Previously, HCV present in a relapse patient was found to harbor a mutation known to be lethal to HCV genotype 1b. The point mutation encodes the amino acid substitution W501R in the helicase RNA binding site. To examine how the W501R substitution affects NS3 helicase activity in a genotype 3a background, wild type and W501R genotype 3a NS3 alleles were sub-cloned, expressed in E. coli, and the recombinant proteins were purified and characterized. The impact of the W501R allele on genotype 2a and 3a subgenomic replicons was also analyzed. Assays monitoring helicase-catalyzed DNA and RNA unwinding revealed that the catalytic efficiency of wild type genotype 3a NS3 helicase was more than 600 times greater than the W501R protein. Other assays revealed that the W501R protein bound DNA less than 2 times weaker than wild type, and both proteins hydrolyzed ATP at similar rates. In Huh7.5 cells, both genotype 2a and 3a subgenomic HCV replicons harboring the W501R allele showed a severe defect in replication. Since the W501R allele is carried as a minor variant, its replication would therefore need to be attributed to the trans-complementation by other wild type quasispecies.

  10. A Point Mutation in the N-Terminal Amphipathic Helix α0 in NS3 Promotes Hepatitis C Virus Assembly by Altering Core Localization to the Endoplasmic Reticulum and Facilitating Virus Budding.

    Science.gov (United States)

    Yan, Yu; He, Ying; Boson, Bertrand; Wang, Xuesong; Cosset, François-Loïc; Zhong, Jin

    2017-03-15

    The assembly of hepatitis C virus (HCV), a complicated process in which many viral and cellular factors are involved, has not been thoroughly deciphered. NS3 is a multifunctional protein that contains an N-terminal amphipathic α helix (designated helix α0), which is crucial for the membrane association and stability of NS3 protein, followed by a serine protease domain and a C-terminal helicase/NTPase domain. NS3 participates in HCV assembly likely through its C-terminal helicase domain, in which all reported adaptive mutations enhancing virion assembly reside. In this study, we determined that the N-terminal helix α0 of NS3 may contribute to HCV assembly. We identified a single mutation from methionine to threonine at amino acid position 21 (M21T) in helix α0, which significantly promoted viral production while having no apparent effect on the membrane association and protease activity of NS3. Subsequent analyses demonstrated that the M21T mutation did not affect HCV genome replication but rather promoted virion assembly. Further study revealed a shift in the subcellular localization of core protein from lipid droplets (LD) to the endoplasmic reticulum (ER). Finally, we showed that the M21T mutation increased the colocalization of core proteins and viral envelope proteins, leading to a more efficient envelopment of viral nucleocapsids. Collectively, the results of our study revealed a new function of NS3 helix α0 and aid understanding of the role of NS3 in HCV virion morphogenesis.IMPORTANCE HCV NS3 protein possesses the protease activity in its N-terminal domain and the helicase activity in its C-terminal domain. The role of NS3 in virus assembly has been mainly attributed to its helicase domain, because all adaptive mutations enhancing progeny virus production are found to be within this domain. Our study identified, for the first time to our knowledge, an adaptive mutation within the N-terminal helix α0 domain of NS3 that significantly enhanced virus

  11. Structural features of NS3 of Dengue virus serotypes 2 and 4 in solution and insight into RNA binding and the inhibitory role of quercetin.

    Science.gov (United States)

    Pan, Ankita; Saw, Wuan Geok; Subramanian Manimekalai, Malathy Sony; Grüber, Ardina; Joon, Shin; Matsui, Tsutomu; Weiss, Thomas M; Grüber, Gerhard

    2017-05-01

    Dengue virus (DENV), which has four serotypes (DENV-1 to DENV-4), is the causative agent of the viral infection dengue. DENV nonstructural protein 3 (NS3) comprises a serine protease domain and an RNA helicase domain which has nucleotide triphosphatase activities that are essential for RNA replication and viral assembly. Here, solution X-ray scattering was used to provide insight into the overall structure and flexibility of the entire NS3 and its recombinant helicase and protease domains for Dengue virus serotypes 2 and 4 in solution. The DENV-2 and DENV-4 NS3 forms are elongated and flexible in solution. The importance of the linker residues in flexibility and domain-domain arrangement was shown by the compactness of the individual protease and helicase domains. Swapping of the 174 PPAVP 179 linker stretch of the related Hepatitis C virus (HCV) NS3 into DENV-2 NS3 did not alter the elongated shape of the engineered mutant. Conformational alterations owing to RNA binding are described in the protease domain, which undergoes substantial conformational alterations that are required for the optimal catalysis of bound RNA. Finally, the effects of ATPase inhibitors on the enzymatically active DENV-2 and DENV-4 NS3 and the individual helicases are presented, and insight into the allosteric effect of the inhibitor quercetin is provided.

  12. Hepatitis C Virus Genotype 1 to 6 Protease Inhibitor Escape Variants

    DEFF Research Database (Denmark)

    Serre, Stéphanie B N; Jensen, Sanne B; Ghanem, Lubna

    2016-01-01

    Hepatitis C virus (HCV) NS3 protease inhibitors (PIs) are important components of novel HCV therapy regimens. Studies of PI resistance initially focused on genotype 1. Therefore, knowledge on determinants of PI resistance for the highly prevalent genotypes 2-6 remains limited. Using Huh7.5 cell...

  13. In Vitro Activity of Simeprevir against Hepatitis C Virus Genotype 1 Clinical Isolates and Its Correlation with NS3 Sequence and Site-Directed Mutants

    Science.gov (United States)

    Fevery, Bart; Vijgen, Leen; Jacobs, Tom; De Meyer, Sandra; Lenz, Oliver

    2015-01-01

    Simeprevir (TMC435) is a once-daily, single-pill, oral hepatitis C virus (HCV) NS3 protease inhibitor approved for the treatment of chronic HCV infection. Phenotypic characterization of baseline isolates and isolates from HCV genotype 1-infected patients failing with a simeprevir-based regimen was performed using chimeric replicons carrying patient-derived NS3 protease sequences. Cutoff values differentiating between full susceptibility to simeprevir (≤2.0-fold reduction in simeprevir activity) and low-level versus high-level resistance (≥50-fold reduction in simeprevir activity) were determined. The median simeprevir fold change in the 50% effective concentration (FC) of pretreatment genotype 1a isolates, with and without Q80K, and genotype 1b isolates was 11, 0.9, and 0.4, respectively. Naturally occurring NS3 polymorphisms that reduced simeprevir activity, other than Q80K, were uncommon in the simeprevir studies and generally conferred low-level resistance in vitro. Although the proportion of patients with failure differed by HCV geno/subtype and/or presence of baseline Q80K, the level of simeprevir resistance observed at failure was similarly high irrespective of type of failure, HCV genotype 1 subtype, and presence or absence of baseline Q80K. At the end of the study, simeprevir activity against isolates that lost the emerging amino acid substitution returned to pretreatment values. Activity of simeprevir against clinical isolates and site-directed mutant replicons harboring the corresponding single or double amino acid substitutions correlated well, showing that simeprevir resistance can be attributed to these substitutions. In conclusion, pretreatment NS3 isolates were generally fully susceptible (FC, ≤2.0) or conferred low-level resistance to simeprevir in vitro (FC, >2.0 and <50). Treatment failure with a simeprevir-based regimen was associated with emergence of high-level-resistance variants (FC, ≥50). PMID:26392483

  14. hcv

    African Journals Online (AJOL)

    boaz

    ABSTRACT. Background: Hepatitis C virus (HCV) infection is a major public health concern. The aim of this study was to ascertain the seroprevalence and risk factors of HCV antibodies among pregnant women in Anyigba, Kogi State North Central Nigeria. Materials and methods:Blood samples (5mls) were collected from ...

  15. Inflammatory markers neopterin and alanine aminotransferase in HCV patients treated with HCV NS3.4A protease inhibitor telaprevir (VX-950) and/or peginterferon alfa-2a

    NARCIS (Netherlands)

    Gelderblom, Huub C.; Zeuzem, Stefan; Weegink, Christine J.; Forestier, Nicole; McNair, Lindsay; Purdy, Susan; Dijkgraaf, Marcel G. W.; Jansen, Peter L. M.; Reesink, Henk W.

    2008-01-01

    OBJECTIVE: Neopterin is a marker of monocyte/macrophage activity. Alanine aminotransferase (ALAT) is a marker of hepatocyte injury. The aim of this study was to determine changes in neopterin and ALAT levels, as markers of inflammation, in two ancillary studies during two-phase 1b trials of

  16. Small molecule inhibitors of HCV replication from Pomegranate

    Science.gov (United States)

    Reddy, B. Uma; Mullick, Ranajoy; Kumar, Anuj; Sudha, Govindarajan; Srinivasan, Narayanaswamy; Das, Saumitra

    2014-06-01

    Hepatitis C virus (HCV) is the causative agent of end-stage liver disease. Recent advances in the last decade in anti HCV treatment strategies have dramatically increased the viral clearance rate. However, several limitations are still associated, which warrant a great need of novel, safe and selective drugs against HCV infection. Towards this objective, we explored highly potent and selective small molecule inhibitors, the ellagitannins, from the crude extract of Pomegranate (Punica granatum) fruit peel. The pure compounds, punicalagin, punicalin, and ellagic acid isolated from the extract specifically blocked the HCV NS3/4A protease activity in vitro. Structural analysis using computational approach also showed that ligand molecules interact with the catalytic and substrate binding residues of NS3/4A protease, leading to inhibition of the enzyme activity. Further, punicalagin and punicalin significantly reduced the HCV replication in cell culture system. More importantly, these compounds are well tolerated ex vivo and`no observed adverse effect level' (NOAEL) was established upto an acute dose of 5000 mg/kg in BALB/c mice. Additionally, pharmacokinetics study showed that the compounds are bioavailable. Taken together, our study provides a proof-of-concept approach for the potential use of antiviral and non-toxic principle ellagitannins from pomegranate in prevention and control of HCV induced complications.

  17. Identification of Hydroxyanthraquinones as Novel Inhibitors of Hepatitis C Virus NS3 Helicase

    Directory of Open Access Journals (Sweden)

    Atsushi Furuta

    2015-08-01

    Full Text Available Hepatitis C virus (HCV is an important etiological agent of severe liver diseases, including cirrhosis and hepatocellular carcinoma. The HCV genome encodes nonstructural protein 3 (NS3 helicase, which is a potential anti-HCV drug target because its enzymatic activity is essential for viral replication. Some anthracyclines are known to be NS3 helicase inhibitors and have a hydroxyanthraquinone moiety in their structures; mitoxantrone, a hydroxyanthraquinone analogue, is also known to inhibit NS3 helicase. Therefore, we hypothesized that the hydroxyanthraquinone moiety alone could also inhibit NS3 helicase. Here, we performed a structure–activity relationship study on a series of hydroxyanthraquinones by using a fluorescence-based helicase assay. Hydroxyanthraquinones inhibited NS3 helicase with IC50 values in the micromolar range. The inhibitory activity varied depending on the number and position of the phenolic hydroxyl groups, and among different hydroxyanthraquinones examined, 1,4,5,8-tetrahydroxyanthraquinone strongly inhibited NS3 helicase with an IC50 value of 6 µM. Furthermore, hypericin and sennidin A, which both have two hydroxyanthraquinone-like moieties, were found to exert even stronger inhibition with IC50 values of 3 and 0.8 µM, respectively. These results indicate that the hydroxyanthraquinone moiety can inhibit NS3 helicase and suggest that several key chemical structures are important for the inhibition.

  18. Direct anti-HCV agents

    Directory of Open Access Journals (Sweden)

    Xingquan Zhang

    2016-01-01

    Full Text Available Unlike human immunodeficiency virus (HIV and hepatitis B virus (HBV, hepatitis C virus (HCV infection is a curable disease. Current direct antiviral agent (DAA targets are focused on HCV NS3/4A protein (protease, NS5B protein (polymerase and NS5A protein. The first generation of DAAs includes boceprevir and telaprevir, which are protease inhibitors and were approved for clinical use in 2011. The cure rate for genotype 1 patients increased from 45% to 70% when boceprevir or telaprevir was added to standard PEG-IFN/ribavirin. More effective and less toxic second generation DAAs supplanted these drugs by 2013. The second generation of DAAs includes sofosbuvir (Sovaldi, simeprevir (Olysio, and fixed combination medicines Harvoni and Viekira Pak. These drugs increase cure rates to over 90% without the need for interferon and effectively treat all HCV genotypes. With these drugs the “cure HCV” goal has become a reality. Concerns remain about drug resistance mutations and the high cost of these drugs. The investigation of new HCV drugs is progressing rapidly; fixed dose combination medicines in phase III clinical trials include Viekirax, asunaprevir+daclatasvir+beclabuvir, grazoprevir+elbasvir and others.

  19. Similarities between Human Immunodeficiency Virus Type 1 and Hepatitis C Virus Genetic and Phenotypic Protease Quasispecies Diversity.

    Science.gov (United States)

    Martinez, Miguel Angel; Nevot, Maria; Jordan-Paiz, Ana; Franco, Sandra

    2015-10-01

    Human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) are two highly variable RNA viruses that cause chronic infections in humans. Although HCV likely preceded the AIDS epidemic by some decades, the global spread of both viruses is a relatively recent event. Nevertheless, HCV global diversity is higher than that of HIV-1. To identify differences in mutant diversity, we compared the HIV-1 protease and HCV NS3 protease quasispecies. Three protease gene quasispecies samples per virus, isolated from a total of six infected patients, were genetically and phenotypically analyzed at high resolution (HIV-1, 308 individual clones; HCV, 299 clones). Single-nucleotide variant frequency did not differ between quasispecies from the two viruses (HIV-1, 2.4 × 10(-3) ± 0.4 × 10(-3); HCV, 2.1 × 10(-3) ± 0.5 × 10(-3)) (P = 0.1680). The proportion of synonymous substitutions to potential synonymous sites was similar (3.667 ± 0.6667 and 2.183 ± 0.9048, respectively) (P = 0.2573), and Shannon's entropy values did not differ between HIV-1 and HCV (0.84 ± 0.02 and 0.83 ± 0.12, respectively) (P = 0.9408). Of note, 65% (HIV-1) and 67% (HCV) of the analyzed enzymes displayed detectable protease activity, suggesting that both proteases have a similar mutational robustness. In both viruses, there was a rugged protease enzymatic activity landscape characterized by a sharp peak, representing the master sequence, surrounded by a collection of diverse variants present at lower frequencies. These results indicate that nucleotide quasispecies diversification during chronic infection is not responsible for the higher worldwide genetic diversity observed in HCV. HCV global diversity is higher than that of HIV-1. We asked whether HCV genetic diversification during infection is responsible for the higher worldwide genetic diversity observed in HCV. To this end, we analyzed and compared the genotype and enzymatic activities of HIV-1 and HCV protease quasispecies existing in

  20. Enhanced and sustained CD8+ T cell responses with an adenoviral vector-based hepatitis C virus vaccine encoding NS3 linked to the MHC class II chaperone protein invariant chain

    DEFF Research Database (Denmark)

    Mikkelsen, Marianne; Holst, Peter Johannes; Bukh, Jens

    2011-01-01

    memory. Functionally, the AdIiNS3-vaccinated mice had a significantly increased cytotoxic capacity compared with the AdNS3 group. The AdIiNS3-induced CD8(+) T cells protected mice from infection with recombinant vaccinia virus expressing HCV NS3 of heterologous 1b strains, and studies in knockout mice...

  1. Biliverdin inhibits hepatitis C virus nonstructural 3/4A protease activity: mechanism for the antiviral effects of heme oxygenase?

    Science.gov (United States)

    Zhu, Zhaowen; Wilson, Anne T; Luxon, Bruce A; Brown, Kyle E; Mathahs, M Meleah; Bandyopadhyay, Sarmistha; McCaffrey, Anton P; Schmidt, Warren N

    2010-12-01

    Induction of heme oxygenase-1 (HO-1) inhibits hepatitis C virus (HCV) replication. Of the products of the reaction catalyzed by HO-1, iron has been shown to inhibit HCV ribonucleic acid (RNA) polymerase, but little is known about the antiviral activity of biliverdin (BV). Herein, we report that BV inhibits viral replication and viral protein expression in a dose-dependent manner in replicons and cells harboring the infectious J6/JFH construct. Using the SensoLyte 620 HCV Protease Assay with a wide wavelength excitation/emission (591 nm/622 nm) fluorescence energy transfer peptide, we found that both recombinant and endogenous nonstructural 3/4A (NS3/4A) protease from replicon microsomes are potently inhibited by BV. Of the tetrapyrroles tested, BV was the strongest inhibitor of NS3/4A activity, with a median inhibitory concentration (IC(50)) of 9 μM, similar to that of the commercial inhibitor, AnaSpec (Fremont, CA) #25346 (IC(50) 5 μM). Lineweaver-Burk plots indicated mixed competitive and noncompetitive inhibition of the protease by BV. In contrast, the effects of bilirubin (BR) on HCV replication and NS3/4A were much less potent. Because BV is rapidly converted to BR by biliverdin reductase (BVR) intracellularly, the effect of BVR knockdown on BV antiviral activity was assessed. After greater than 80% silencing of BVR, inhibition of viral replication by BV was enhanced. BV also increased the antiviral activity of α-interferon in replicons. BV is a potent inhibitor of HCV NS3/4A protease, which likely contributes to the antiviral activity of HO-1. These findings suggest that BV or its derivatives may be useful in future drug therapies targeting the NS3/4A protease. Copyright © 2010 American Association for the Study of Liver Diseases.

  2. Geno2pheno[HCV] - A Web-based Interpretation System to Support Hepatitis C Treatment Decisions in the Era of Direct-Acting Antiviral Agents.

    Directory of Open Access Journals (Sweden)

    Prabhav Kalaghatgi

    Full Text Available The face of hepatitis C virus (HCV therapy is changing dramatically. Direct-acting antiviral agents (DAAs specifically targeting HCV proteins have been developed and entered clinical practice in 2011. However, despite high sustained viral response (SVR rates of more than 90%, a fraction of patients do not eliminate the virus and in these cases treatment failure has been associated with the selection of drug resistance mutations (RAMs. RAMs may be prevalent prior to the start of treatment, or can be selected under therapy, and furthermore they can persist after cessation of treatment. Additionally, certain DAAs have been approved only for distinct HCV genotypes and may even have subtype specificity. Thus, sequence analysis before start of therapy is instrumental for managing DAA-based treatment strategies. We have created the interpretation system geno2pheno[HCV] (g2p[HCV] to analyse HCV sequence data with respect to viral subtype and to predict drug resistance. Extensive reviewing and weighting of literature related to HCV drug resistance was performed to create a comprehensive list of drug resistance rules for inhibitors of the HCV protease in non-structural protein 3 (NS3-protease: Boceprevir, Paritaprevir, Simeprevir, Asunaprevir, Grazoprevir and Telaprevir, the NS5A replicase factor (Daclatasvir, Ledipasvir, Elbasvir and Ombitasvir, and the NS5B RNA-dependent RNA polymerase (Dasabuvir and Sofosbuvir. Upon submission of up to eight sequences, g2p[HCV] aligns the input sequences, identifies the genomic region(s, predicts the HCV geno- and subtypes, and generates for each DAA a drug resistance prediction report. g2p[HCV] offers easy-to-use and fast subtype and resistance analysis of HCV sequences, is continuously updated and freely accessible under http://hcv.geno2pheno.org/index.php. The system was partially validated with respect to the NS3-protease inhibitors Boceprevir, Telaprevir and Simeprevir by using data generated with recombinant

  3. A Novel Adeno-Associated Virus-Based Genetic Vaccine Encoding the Hepatitis C Virus NS3/4 Protein Exhibits Immunogenic Properties in Mice Superior to Those of an NS3-Protein-Based Vaccine.

    Directory of Open Access Journals (Sweden)

    Fengqin Zhu

    Full Text Available More than 170 million individuals worldwide are infected with hepatitis C virus (HCV, and up to an estimated 30% of chronically infected individuals will go on to develop progressive liver disease. Despite the recent advances in antiviral treatment of HCV infection, it remains a major public health problem. Thus, development of an effective vaccine is urgently required. In this study, we constructed novel adeno-associated virus (AAV vectors expressing the full-length NS3 or NS3/4 protein of HCV genotype 1b. The expression of the NS3 or NS3/4 protein in HepG2 cells was confirmed by western blotting. C57BL/6 mice were intramuscularly immunised with a single injection of AAV vectors, and the resultant immune response was investigated. The AAV2/rh32.33.NS3/4 vaccine induced stronger humoral and cellular responses than did the AAV2/rh32.33.NS3 vaccine. Our results demonstrate that AAV-based vaccines exhibit considerable potential for the development of an effective anti-HCV vaccine.

  4. Naringenin and quercetin--potential anti-HCV agents for NS2 protease targets.

    Science.gov (United States)

    Lulu, S Sajitha; Thabitha, A; Vino, S; Priya, A Mohana; Rout, Madhusmita

    2016-01-01

    Nonstructural proteins of hepatitis C virus had drawn much attention for the scientific fraternity in drug discovery due to its important role in the disease. 3D structure of the protein was predicted using molecular modelling protocol. Docking studies of 10 medicinal plant compounds and three drugs available in the market (control) with NS2 protease were employed by using rigid docking approach of AutoDock 4.2. Among the molecules tested for docking study, naringenin and quercetin revealed minimum binding energy of - 7.97 and - 7.95 kcal/mol with NS2 protease. All the ligands were docked deeply within the binding pocket region of the protein. The docking study results showed that these compounds are potential inhibitors of the target; and also all these docked compounds have good inhibition constant, vdW+Hbond+desolv energy with best RMSD value.

  5. Patients treated with first-generation HCV protease inhibitors exhibit high ribavirin concentrations.

    Science.gov (United States)

    Bodeau, Sandra; Nguyen-Khac, Eric; Solas, Caroline; Bennis, Youssef; Capron, Dominique; Duverlie, Gilles; Brochot, Etienne

    2015-05-01

    Anemia is a well-known RBV-related event in HCV therapy which is exacerbated by the addition of telaprevir and boceprevir. This retrospective study evaluated and compared ribavirin exposure and parameters able to influence hemoglobin decrease in a large population of patients treated with dual or triple therapy. Patients on triple therapy had higher ribavirin concentrations at week 12 of treatment (3460 ng/mL vs. 1843 ng/mL; P 20 mL/min/1.73 m(2) decrease in eGFR at week 12 was higher among patients on triple therapy: 32%, 14%, and 5% for boceprevir, telaprevir, and dual therapy, respectively (P = .025 and .026). No correlation was observed between boceprevir and telaprevir concentrations and hemoglobin or eGFR decrease. Exacerbation of anemia in patients on triple therapy is related to higher ribavirin concentrations. We provide an explanation for this increase in plasma RBV concentration. Triple therapy with PEG-IFN, RBV, and telaprevir or boceprevir will remain the only HCV treatment option for many patients. Our data show that the RBV dose can be decreased while maintaining adequate plasma concentrations and reducing anemia. © 2015, The American College of Clinical Pharmacology.

  6. In vitro anti-HCV activities of Saxifraga melanocentra and its related polyphenolic compounds.

    Science.gov (United States)

    Zuo, Guo-Ying; Li, Zheng-Quan; Chen, Li-Rong; Xu, Xiao-Jie

    2005-01-01

    The aim of this study was to search for new natural anti-HCV agents from Chinese herbal medicine. Bioactivity-guided extraction and isolation methods were used. Active part and pure compounds were obtained from ethanolic extract of Saxifraga melanocentra Franch. and their in vitro inhibitory activities (IC50) against HCV NS3 serine protease were tested by enzyme-linked immunosorbent assay. Results showed that the polyphenolic ethyl acetate part of the herbal extract was the most active, and from this 18 polyphenols representing active compounds were isolated and identified. IC50 values of these compounds and five related ones were obtained. A broad-degree of anti-HCV activity was observed among them in the following order: gallated esters of D-glucose and rutin (0.68-4.86 microM)> flavonoids (33.11-370.37 microM)> gallic acid and its methyl and ethyl esters, Bergenin and others (over 1000 microM). The most active compound was 1,2,3,4,6-penta-O-galloyl-beta-D-glucoside (0.68 microM). In conclusion, polyphenols were responsible for the anti-HCV constitution of S. melanocentra, and multigallated esters of D-glucose possessed the strongest inhibition against HCV NS3 serine protease and little cytotoxic effect, suggesting the potential use of these compounds for designing and developing drugs for treatment of the viral infection.

  7. Molecular dynamic simulation of complex NS2B-NS3 DENV2 ...

    African Journals Online (AJOL)

    In many researches, several models of peptides inhibitor were generated in complexes with the NS2B-NS3 DENV2 protease by performing molecular docking. The goal of this research was to study the interaction of ligands as inhibitors for protein (enzyme) in solvent explicit condition by performing molecular dynamics ...

  8. Molecular dynamic simulation of complex NS2B-NS3 DENV2 ...

    African Journals Online (AJOL)

    Nissia

    2013-07-10

    Jul 10, 2013 ... many researches, several models of peptides inhibitor were generated in complexes with the NS2B-NS3. DENV2 protease by performing molecular docking. The goal of this research was to study the interaction of ligands as inhibitors for protein (enzyme) in solvent explicit condition by performing molecular ...

  9. Non-structural protein NS3/NS3a is required for propagation of bluetongue virus in Culicoides sonorensis

    NARCIS (Netherlands)

    Feenstra, Femke; Drolet, B.S.; Boonstra, Jan; Rijn, Van P.A.

    2015-01-01

    Background: Bluetongue virus (BTV) causes non-contagious haemorrhagic disease in ruminants and is transmitted by Culicoides spp. biting midges. BTV encodes four non-structural proteins of which NS3/NS3a is functional in virus release. NS3/NS3a is not essential for in vitro virus replication.

  10. Non-structural protein NS3/NS3a is required for propagation of bluetongue virus in Culicoides sonorensis

    Science.gov (United States)

    Background: Bluetongue virus (BTV) causes non-contagious haemorrhagic disease in ruminants and is transmitted by Culicoides spp. biting midges. BTV encodes four non-structural proteins of which NS3/NS3a is functional in virus release. NS3/NS3a is not essential for in vitro virus replication. However...

  11. Primuline Derivatives That Mimic RNA to Stimulate Hepatitis C Virus NS3 Helicase-catalyzed ATP Hydrolysis*

    Science.gov (United States)

    Sweeney, Noreena L.; Shadrick, William R.; Mukherjee, Sourav; Li, Kelin; Frankowski, Kevin J.; Schoenen, Frank J.; Frick, David N.

    2013-01-01

    ATP hydrolysis fuels the ability of helicases and related proteins to translocate on nucleic acids and separate base pairs. As a consequence, nucleic acid binding stimulates the rate at which a helicase catalyzes ATP hydrolysis. In this study, we searched a library of small molecule helicase inhibitors for compounds that stimulate ATP hydrolysis catalyzed by the hepatitis C virus (HCV) NS3 helicase, which is an important antiviral drug target. Two compounds were found that stimulate HCV helicase-catalyzed ATP hydrolysis, both of which are amide derivatives synthesized from the main component of the yellow dye primuline. Both compounds possess a terminal pyridine moiety, which was critical for stimulation. Analogs lacking a terminal pyridine inhibited HCV helicase catalyzed ATP hydrolysis. Unlike other HCV helicase inhibitors, the stimulatory compounds differentiate between helicases isolated from various HCV genotypes and related viruses. The compounds only stimulated ATP hydrolysis catalyzed by NS3 purified from HCV genotype 1b. They inhibited helicases from other HCV genotypes (e.g. 1a and 2a) or related flaviviruses (e.g. Dengue virus). The stimulatory compounds interacted with HCV helicase in the absence of ATP with dissociation constants of about 2 μm. Molecular modeling and site-directed mutagenesis studies suggest that the stimulatory compounds bind in the HCV helicase RNA-binding cleft near key residues Arg-393, Glu-493, and Ser-231. PMID:23703611

  12. HCV Induces Telomerase Reverse Transcriptase, Increases Its Catalytic Activity, and Promotes Caspase Degradation in Infected Human Hepatocytes

    Science.gov (United States)

    Zhu, Zhaowen; Tran, Huy; Mathahs, M. Meleah; Moninger, Thomas O.; Schmidt, Warren N.

    2017-01-01

    Introduction Telomerase repairs the telomeric ends of chromosomes and is active in nearly all malignant cells. Hepatitis C virus (HCV) is known to be oncogenic and potential interactions with the telomerase system require further study. We determined the effects of HCV infection on human telomerase reverse transcriptase (TERT) expression and enzyme activity in primary human hepatocytes and continuous cell lines. Results Primary human hepatocytes and Huh-7.5 hepatoma cells showed early de novo TERT protein expression 2–4 days after infection and these events coincided with increased TERT promoter activation, TERT mRNA, and telomerase activity. Immunoprecipitation studies demonstrated that NS3-4A protease-helicase, in contrast to core or NS5A, specifically bound to the C-terminal region of TERT through interactions between helicase domain 2 and protease sequences. Increased telomerase activity was noted when NS3-4A was transfected into cells, when added to reconstituted mixtures of TERT and telomerase RNA, and when incubated with high molecular weight telomerase ‘holoenzyme’ complexes. The NS3-4A catalytic effect on telomerase was inhibited with primuline or danoprevir, agents that are known to inhibit NS3 helicase and protease activities respectively. In HCV infected cells, NS3-4A could be specifically recovered with telomerase holoenzyme complexes in contrast to NS5A or core protein. HCV infection also activated the effector caspase 7 which is known to target TERT. Activation coincided with the appearance of lower molecular weight carboxy-terminal fragment(s) of TERT, chiefly sized at 45 kD, which could be inhibited with pancaspase or caspase 7 inhibitors. Conclusions HCV infection induces TERT expression and stimulates telomerase activity in addition to triggering Caspase activity that leads to increased TERT degradation. These activities suggest multiple points whereby the virus can influence neoplasia. The NS3-4A protease-helicase can directly bind to TERT

  13. Artificial neural network for prediction of antigenic activity for a major conformational epitope in the hepatitis C virus NS3 protein.

    Science.gov (United States)

    Lara, James; Wohlhueter, Robert M; Dimitrova, Zoya; Khudyakov, Yury E

    2008-09-01

    Insufficient knowledge of general principles for accurate quantitative inference of biological properties from sequences is a major obstacle in the rationale design of proteins with predetermined activities. Due to this deficiency, protein engineering frequently relies on the use of computational approaches focused on the identification of quantitative structure-activity relationship (SAR) for each specific task. In the current article, a computational model was developed to define SAR for a major conformational antigenic epitope of the hepatitis C virus (HCV) non-structural protein 3 (NS3) in order to facilitate a rationale design of HCV antigens with improved diagnostically relevant properties. We present an artificial neural network (ANN) model that connects changes in the antigenic properties and structure of HCV NS3 recombinant proteins representing all 6 HCV genotypes. The ANN performed quantitative predictions of the enzyme immunoassay (EIA) Signal/Cutoff (S/Co) profiles from sequence information alone with 89.8% accuracy. Amino acid positions and physicochemical factors strongly associated with the HCV NS3 antigenic properties were identified. The positions most significantly contributing to the model were mapped on the NS3 3D structure. The location of these positions validates the major associations found by the ANN model between antigenicity and structure of the HCV NS3 proteins. Matlab code is available at the following URL address: http://bio-ai.myeweb.net/box_widget.html

  14. Hepatitis C Virus Genotype 1 to 6 Protease Inhibitor Escape Variants

    DEFF Research Database (Denmark)

    Serre, Stéphanie B N; Jensen, Sanne B; Ghanem, Lubna

    2016-01-01

    Hepatitis C virus (HCV) NS3 protease inhibitors (PIs) are important components of novel HCV therapy regimens. Studies of PI resistance initially focused on genotype 1. Therefore, knowledge on determinants of PI resistance for the highly prevalent genotypes 2-6 remains limited. Using Huh7.5 cell...... fitness, depending on the original recombinant and the substitution. Across genotypes, fitness impairment induced by resistance substitutions was primarily due to decreased replication. Most identified combinations of substitutions increased resistance or fitness. Combinations of resistance substitutions...

  15. In-cell protease assay systems based on trans-localizing molecular beacon proteins using HCV protease as a model system.

    Directory of Open Access Journals (Sweden)

    Jeong Hee Kim

    Full Text Available This study describes a sensitive in-cell protease detection system that enables direct fluorescence detection of a target protease and its inhibition inside living cells. This live-cell imaging system provides a fluorescent molecular beacon protein comprised of an intracellular translocation signal sequence, a protease-specific cleavage sequence, and a fluorescent tag sequence(s. The molecular beacon protein is designed to change its intracellular localization upon cleavage by a target protease, i.e., from the cytosol to a subcellular organelle or from a subcellular organelle to the cytosol. Protease activity can be monitored at the single cell level, and accordingly the entire cell population expressing the protease can be accurately enumerated. The clear cellular change in fluorescence pattern makes this system an ideal tool for various life science and drug discovery research, including high throughput and high content screening applications.

  16. Elimination of HCV via a non-ISG-mediated mechanism by vaniprevir and BMS-788329 combination therapy in human hepatocyte chimeric mice.

    Science.gov (United States)

    Uchida, Takuro; Hiraga, Nobuhiko; Imamura, Michio; Yoshimi, Satoshi; Kan, Hiromi; Miyaki, Eisuke; Tsuge, Masataka; Abe, Hiromi; Hayes, C Nelson; Aikata, Hiroshi; Ishida, Yuji; Tateno, Chise; Ellis, Joan D; Chayama, Kazuaki

    2016-02-02

    We previously reported that interferon (IFN)-free direct-acting antiviral combination treatment succeeded in eradicating genotype 1b hepatitis C virus (HCV) in human hepatocyte chimeric mice. In this study, we examined the effect of vaniprevir (MK7009, NS3/4A protease inhibitor) and BMS-788329 (NS5A inhibitor) combination treatment on HCV genotype 1b and the expression of IFN-stimulated genes (ISGs) using a subgenomic replicon system and the same animal model. Combination treatment with vaniprevir and BMS-788329 significantly reduced HCV replication compared to vaniprevir monotherapy in HCV replicon cells (Huh7/Rep-Feo cells). HCV genotype 1b-infected human hepatocyte chimeric mice were treated with vaniprevir alone or in combination with BMS-788329 for four weeks. Vaniprevir monotherapy reduced serum HCV RNA titers in mice, but viral breakthrough was observed in mice with high HCV titers. Ultra-deep sequence analysis revealed a predominant replacement by drug-resistant substitutions at 168 in HCV NS3 region in these mice. Conversely, in mice with low HCV titers, HCV was eradicated by vaniprevir monotherapy without viral breakthrough. In contrast to monotherapy, combination treatment with vaniprevir and BMS-788329 succeeded in completely eradicating HCV regardless of serum viral titer. IFN-alpha treatment significantly increased ISG expression; however, vaniprevir and BMS-788329 combination treatment caused no increase in ISG expression both in cultured cells and in mouse livers. Therefore, combination treatment with vaniprevir and BMS-788329 eliminated HCV via a non-ISG-mediated mechanism. This oral treatment might offer an alternative DAA combination therapy for patients with chronic hepatitis C. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Raltegravir, tenofovir, and emtricitabine in an HIV-Infected patient with HCV chronic hepatitis, NNRTI intolerance and protease inhibitors-induced severe liver Toxicity

    Directory of Open Access Journals (Sweden)

    Ortu F

    2010-02-01

    Full Text Available Abstract Background in HIV-infected patients with HCV-related chronic hepatitis, liver impairment and drug toxicity may substantially reduce the number of possible therapeutic options. Case Description we here describe the case of an HCV-HIV coinfected woman who had repeated severe episodes of drug-related liver toxicity with indinavir, saquinavir, fosamprenavir, and darunavir, with minimal further therapeutic options left in this class. Previous treatment-limiting side effects with efavirenz and nevirapine also precluded use of non-nucleoside reverse transcriptase inhibitors. Introduction of an integrase-inhibitor regimen based on raltegravir, tenofovir, and emtricitabine allowed a prompt achievement of undetectable viral load and a substantial rise of CD4 count to high levels, with no subsequent episodes of hepatic toxicity, and no other side effects. Conclusions given the relatively common prevalence of HCV-related chronic hepatitis among people with HIV, raltegravir might represent an important alternative option for a substantial number of patients who cannot be treated with protease inhibitors or NNRTI because of drug-related hepatic toxicity.

  18. In Situ Hepatitis C NS3 Protein Detection Is Associated with High Grade Features in Hepatitis C-Associated B-Cell Non-Hodgkin Lymphomas.

    Directory of Open Access Journals (Sweden)

    Danielle Canioni

    Full Text Available Hepatitis C Virus (HCV infection is associated with the B-cell non-Hodgkin lymphomas (NHL, preferentially marginal zone lymphomas (MZL and diffuse large B-cell lymphomas (DLBCL. While chronic antigenic stimulation is a main determinant of lymphomagenesis in marginal zone lymphomas (MZL, a putative role of HCV infection of B-cells is supported by in vitro studies. We performed a pathological study within the "ANRS HC-13 LymphoC" observational study focusing on in situ expression of the oncogenic HCV non structural 3 (NS3 protein. Lympho-C study enrolled 116 HCV-positive patients with B-NHL of which 86 histological samples were collected for centralized review. Main histological subtypes were DLBCL (36% and MZL (34%. Almost half of DLBCL (12/26 were transformed from underlying small B-cell lymphomas. NS3 immunostaining was found positive in 17 of 37 tested samples (46%. There was a striking association between NS3 detection and presence of high grade lymphoma features: 12 out of 14 DLBCL were NS3+ compared to only 4 out of 14 MZL (p = 0.006. Moreover, 2 among the 4 NS3+ MZL were enriched in large cells. Remarkably, this study supports a new mechanism of transformation with a direct oncogenic role of HCV proteins in the occurrence of high-grade B lymphomas.

  19. Single-molecule imaging reveals the translocation and DNA looping dynamics of hepatitis C virus NS3 helicase.

    Science.gov (United States)

    Lin, Chang-Ting; Tritschler, Felix; Lee, Kyung Suk; Gu, Meigang; Rice, Charles M; Ha, Taekjip

    2017-07-01

    Non-structural protein 3 (NS3) is an essential enzyme and a therapeutic target of hepatitis C virus (HCV). Compared to NS3-catalyzed nucleic acids unwinding, its translation on single stranded nucleic acids have received relatively little attention. To investigate the NS3h translocation with single-stranded nucleic acids substrates directly, we have applied a hybrid platform of single-molecule fluorescence detection combined with optical trapping. With the aid of mechanical manipulation and fluorescence localization, we probed the translocase activity of NS3h on laterally stretched, kilobase-size single-stranded DNA and RNA. We observed that the translocation rate of NS3h on ssDNA at a rate of 24.4 nucleotides per second, and NS3h translocates about three time faster on ssRNA, 74 nucleotides per second. The translocation speed was minimally affected by the applied force. A subpopulation of NS3h underwent a novel translocation mode on ssDNA where the stretched DNA shortened gradually and then recovers its original length abruptly before repeating the cycle repetitively. The speed of this mode of translocation was reduced with increasing force. With corroborating data from single-molecule fluorescence resonance energy transfer (smFRET) experiments, we proposed that NS3h can cause repetitive looping of DNA. The smFRET dwell time analysis showed similar translocation time between sole translocation mode versus repetitive looping mode, suggesting that the motor domain exhibits indistinguishable enzymatic activities between the two translocation modes. We propose a potential secondary nucleic acids binding site at NS3h which might function as an anchor point for translocation-coupled looping. © 2017 The Protein Society.

  20. Combination treatment with hepatitis C virus protease and NS5A inhibitors is effective against recombinant genotype 1a, 2a, and 3a viruses

    DEFF Research Database (Denmark)

    Gottwein, Judith M; Jensen, Sanne B; Li, Yi-Ping

    2013-01-01

    mutations allowed generation of 1a(H77) semi-FL virus. Concentration-response profiles revealed the higher efficacy of the NS3 protease inhibitor asunaprevir (BMS-650032) and the NS5A inhibitor daclatasvir (BMS-790052) against 1a(TN and H77) than 3a(S52) viruses. Asunaprevir had intermediate efficacy...... to single-drug treatment, combination treatment with relatively low concentrations of asunaprevir and daclatasvir suppressed infection with all five recombinants. Escaped viruses primarily had substitutions at amino acids in the NS3 protease and NS5A domain I reported to be genotype 1 resistance mutations......With the development of directly acting antivirals, hepatitis C virus (HCV) therapy entered a new era. However, rapid selection of resistance mutations necessitates combination therapy. To study combination therapy in infectious culture systems, we aimed at developing HCV semi-full-length (semi...

  1. Purification and crystallization of dengue and West Nile virus NS2B–NS3 complexes

    Energy Technology Data Exchange (ETDEWEB)

    D’Arcy, Allan, E-mail: allan.darcy@novartis.com; Chaillet, Maxime; Schiering, Nikolaus; Villard, Frederic [Novartis Institutes of Biomedical Research, Protease Platform, Klybeckstrasse 144, CH 4002 Basel (Switzerland); Lim, Siew Pheng [Novartis Institutes of Tropical Diseases (Singapore); Lefeuvre, Peggy [Novartis Institutes of Biomedical Research, Protease Platform, Klybeckstrasse 144, CH 4002 Basel (Switzerland); Erbel, Paul [Novartis Institutes of Biomedical Research, Protease Platform, Klybeckstrasse 144, CH 4002 Basel (Switzerland); Novartis Institutes of Tropical Diseases (Singapore)

    2006-02-01

    Crystals of dengue serotype 2 and West Nile virus NS2B–NS3 protease complexes have been obtained and the crystals of both diffract to useful resolution. Sample homogeneity was essential for obtaining X-ray-quality crystals of the dengue protease. Controlled proteolysis produced a crystallizable fragment of the apo West Nile virus NS2B–NS3 and crystals were also obtained in the presence of a peptidic inhibitor. Both dengue and West Nile virus infections are an increasing risk to humans, not only in tropical and subtropical areas, but also in North America and parts of Europe. These viral infections are generally transmitted by mosquitoes, but may also be tick-borne. Infection usually results in mild flu-like symptoms, but can also cause encephalitis and fatalities. Approximately 2799 severe West Nile virus cases were reported this year in the United States, resulting in 102 fatalities. With this alarming increase in the number of West Nile virus infections in western countries and the fact that dengue virus already affects millions of people per year in tropical and subtropical climates, there is a real need for effective medicines. A possible therapeutic target to combat these viruses is the protease, which is essential for virus replication. In order to provide structural information to help to guide a lead identification and optimization program, crystallizations of the NS2B–NS3 protease complexes from both dengue and West Nile viruses have been initiated. Crystals that diffract to high resolution, suitable for three-dimensional structure determinations, have been obtained.

  2. Bluetongue virus without NS3/NS3a expression is not virulent and protects against virulent bluetongue virus challenge.

    Science.gov (United States)

    Feenstra, Femke; van Gennip, René G P; Maris-Veldhuis, Mieke; Verheij, Eline; van Rijn, Piet A

    2014-09-01

    Bluetongue is a disease in ruminants caused by the bluetongue virus (BTV), and is spread by Culicoides biting midges. Bluetongue outbreaks cause huge economic losses and death in sheep in several parts of the world. The most effective measure to control BTV is vaccination. However, both commercially available vaccines and recently developed vaccine candidates have several shortcomings. Therefore, we generated and tested next-generation vaccines for bluetongue based on the backbone of a laboratory-adapted strain of BTV-1, avirulent BTV-6 or virulent BTV-8. All vaccine candidates were serotyped with VP2 of BTV-8 and did not express NS3/NS3a non-structural proteins, due to induced deletions in the NS3/NS3a ORF. Sheep were vaccinated once with one of these vaccine candidates and were challenged with virulent BTV-8 3 weeks after vaccination. The NS3/NS3a knockout mutation caused complete avirulence for all three BTV backbones, including for virulent BTV-8, indicating that safety is associated with the NS3/NS3a knockout phenotype. Viraemia of vaccine virus was not detected using sensitive PCR diagnostics. Apparently, the vaccine viruses replicated only locally, which will minimize spread by the insect vector. In particular, the vaccine based on the BTV-6 backbone protected against disease and prevented viraemia of challenge virus, showing the efficacy of this vaccine candidate. The lack of NS3/NS3a expression potentially enables the differentiation of infected from vaccinated animals, which is important for monitoring virus spread in vaccinated livestock. The disabled infectious single-animal vaccine for bluetongue presented here is very promising and will be the subject of future studies. © 2014 The Authors.

  3. Determination of the HCV protease inhibitor telaprevir in plasma and dried blood spot by liquid chromatography-tandem mass spectrometry

    NARCIS (Netherlands)

    Verweij-Van Wissen, Corrien P W G M; De Graaff-Teulen, Marga J A; De Kanter, Clara T M M; Aarnoutse, Rob E.; Burger, David M.

    2015-01-01

    Background: Telaprevir is a protease inhibitor used in the treatment of hepatitis C virus infection. Analytical methods for telaprevir should separate the compound from its R-diastereomer VRT-127394, which is 30-fold less active. The objective of this work was to develop liquid chromatography-tandem

  4. Determination of the HCV Protease Inhibitor Telaprevir in Plasma and Dried Blood Spot by Liquid Chromatography-Tandem Mass Spectrometry

    NARCIS (Netherlands)

    Verweij-van Wissen, C.P.W.G.M.; Graaff-Teulen, M.J.A. de; Kanter, C.T.M.M. de; Aarnoutse, R.E.; Burger, D.M.

    2015-01-01

    BACKGROUND: Telaprevir is a protease inhibitor used in the treatment of hepatitis C virus infection. Analytical methods for telaprevir should separate the compound from its R-diastereomer VRT-127394, which is 30-fold less active. The objective of this work was to develop liquid chromatography-tandem

  5. Nationwide experience of treatment with protease inhibitors in chronic hepatitis C patients in denmark

    DEFF Research Database (Denmark)

    Sølund, Christina; Krarup, Henrik; Ramirez, Santseharay

    2014-01-01

    BACKGROUND AND AIMS: The first standard of care in treatment of chronic HCV genotype 1 infection involving directly acting antivirals was protease inhibitors telaprevir or boceprevir combined with pegylated-interferon and ribavirin (triple therapy). Phase III studies include highly selected...... of the RT-PCR amplified NS3 protease were performed in patients without cure following triple therapy. RESULTS: 38 (47%) of the patients achieved cure, 15 (19%) discontinued treatment due to adverse events and remained infected, and 27 (34%) experienced relapse or treatment failure of whom 15 of 21 analyzed...... patients had well-described protease inhibitor resistance variants detected. Most frequently detected protease variants were V36M and/or R155K, and V36M, in patients with genotype 1a and 1b infection, respectively. CONCLUSIONS: The cure rate after triple therapy in a routine clinical setting was 47%, which...

  6. The hepatitis C virus replicon presents a higher barrier to resistance to nucleoside analogs than to nonnucleoside polymerase or protease inhibitors.

    Science.gov (United States)

    McCown, Matthew F; Rajyaguru, Sonal; Le Pogam, Sophie; Ali, Samir; Jiang, Wen-Rong; Kang, Hyunsoon; Symons, Julian; Cammack, Nick; Najera, Isabel

    2008-05-01

    Specific inhibitors of hepatitis C virus (HCV) replication that target the NS3/4A protease (e.g., VX-950) or the NS5B polymerase (e.g., R1479/R1626, PSI-6130/R7128, NM107/NM283, and HCV-796) have advanced into clinical development. Treatment of patients with VX-950 or HCV-796 rapidly selected for drug-resistant variants after a 14-day monotherapy treatment period. However, no viral resistance was identified after monotherapy with R1626 (prodrug of R1479) or NM283 (prodrug of NM107) after 14 days of monotherapy. Based upon the rapid selection of resistance to the protease and nonnucleoside inhibitors during clinical trials and the lack of selection of resistance to the nucleoside inhibitors, we used the replicon system to determine whether nucleoside inhibitors demonstrate a higher genetic barrier to resistance than protease and nonnucleoside inhibitors. Treatment of replicon cells with nucleoside inhibitors at 10 and 15 times the 50% effective concentration resulted in clearance of the replicon, while treatment with a nonnucleoside or protease inhibitor selected resistant colonies. In combination, the presence of a nucleoside inhibitor reduced the frequency of colonies resistant to the other classes of inhibitors. These results indicate that the HCV replicon presents a higher barrier to the selection of resistance to nucleoside inhibitors than to nonnucleoside or protease inhibitors. Furthermore, the combination of a nonnucleoside or protease inhibitor with a nucleoside polymerase inhibitor could have a clear clinical benefit through the delay of resistance emergence.

  7. Differential sensitivity of 5'UTR-NS5A recombinants of hepatitis C virus genotypes 1-6 to protease and NS5A inhibitors

    DEFF Research Database (Denmark)

    Li, Yi-Ping; Ramirez, Santseharay; Humes, Daryl

    2014-01-01

    ) from genotypes 1-6 and 2a(JFH1) NS5B-3' untranslated region, and tested the effects of NS3 protease and NS5A inhibitors on these recombinants. METHODS: The HCV 5-5A recombinants with previously identified mutations in the NS3-helicase (F1464L), NS4A (A1672S), and NS5B (D2979G) were adapted and improved......, by incorporating additional recovered mutations that increased their propagation in Huh7.5 cells. Concentration-response profiles were determined for each DAA agent in replicate infected Huh7.5 cells. RESULTS: Developed efficient 1a(H77), 1a(TN), 3a(S52), 4a(ED43), 5a(SA13), and 6a(HK6a) 5-5A recombinants did...... not require mutations after viral passage in the NS3 protease or NS5A domain-I regions targeted by the drugs. They were inhibited in a concentration-dependent manner by the NS3 protease inhibitors telaprevir, boceprevir, asunaprevir, simeprevir, vaniprevir, faldaprevir, and MK-5172 and by the NS5A inhibitor...

  8. Detection of Natural Resistance-Associated Substitutions by Ion Semiconductor Technology in HCV1b Positive, Direct-Acting Antiviral Agents-Naïve Patients.

    Science.gov (United States)

    Marascio, Nadia; Pavia, Grazia; Strazzulla, Alessio; Dierckx, Tim; Cuypers, Lize; Vrancken, Bram; Barreca, Giorgio Settimo; Mirante, Teresa; Malanga, Donatella; Oliveira, Duarte Mendes; Vandamme, Anne-Mieke; Torti, Carlo; Liberto, Maria Carla; Focà, Alfredo

    2016-08-27

    Naturally occurring resistance-associated substitutions (RASs) can negatively impact the response to direct-acting antivirals (DAAs) agents-based therapies for hepatitis C virus (HCV) infection. Herein, we set out to characterize the RASs in the HCV1b genome from serum samples of DAA-naïve patients in the context of the SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology, 2014) project. We deep-sequenced the NS3/4A protease region of the viral population using the Ion Torrent Personal Genome Machine, and patient-specific majority rule consensus sequence summaries were constructed with a combination of freely available next generation sequencing data analysis software. We detected NS3/4A protease major and minor variants associated with resistance to boceprevir (V36L), telaprevir (V36L, I132V), simeprevir (V36L), and grazoprevir (V36L, V170I). Furthermore, we sequenced part of HCV NS5B polymerase using Sanger-sequencing and detected a natural RAS for dasabuvir (C316N). This mutation could be important for treatment strategies in cases of previous therapy failure.

  9. Detection of Natural Resistance-Associated Substitutions by Ion Semiconductor Technology in HCV1b Positive, Direct-Acting Antiviral Agents-Naïve Patients

    Directory of Open Access Journals (Sweden)

    Nadia Marascio

    2016-08-01

    Full Text Available Naturally occurring resistance-associated substitutions (RASs can negatively impact the response to direct-acting antivirals (DAAs agents-based therapies for hepatitis C virus (HCV infection. Herein, we set out to characterize the RASs in the HCV1b genome from serum samples of DAA-naïve patients in the context of the SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology, 2014 project. We deep-sequenced the NS3/4A protease region of the viral population using the Ion Torrent Personal Genome Machine, and patient-specific majority rule consensus sequence summaries were constructed with a combination of freely available next generation sequencing data analysis software. We detected NS3/4A protease major and minor variants associated with resistance to boceprevir (V36L, telaprevir (V36L, I132V, simeprevir (V36L, and grazoprevir (V36L, V170I. Furthermore, we sequenced part of HCV NS5B polymerase using Sanger-sequencing and detected a natural RAS for dasabuvir (C316N. This mutation could be important for treatment strategies in cases of previous therapy failure.

  10. Solution conformations of Zika NS2B-NS3pro and its inhibition by natural products from edible plants.

    Science.gov (United States)

    Roy, Amrita; Lim, Liangzhong; Srivastava, Shagun; Lu, Yimei; Song, Jianxing

    2017-01-01

    The recent Zika viral (ZIKV) epidemic has been associated with severe neurological pathologies such as neonatal microcephaly and Guillain-Barre syndrome but unfortunately no vaccine or medication is effectively available yet. Zika NS2B-NS3pro is essential for the proteolysis of the viral polyprotein and thereby viral replication. Thus NS2B-NS3pro represents an attractive target for anti-Zika drug discovery/design. Here, we have characterized the solution conformations and catalytic parameters of both linked and unlinked Zika NS2B-NS3pro complexes and found that the unlinked complex manifested well-dispersed NMR spectra. Subsequently with selective isotope-labeling using NMR spectroscopy, we demonstrated that C-terminal residues (R73-K100) of NS2B is highly disordered without any stable tertiary and secondary structures in the Zika NS2B-NS3pro complex in the free state. Upon binding to the well-characterized serine protease inhibitor, bovine pancreatic trypsin inhibitor (BPTI), only the extreme C-terminal residues (L86-K100) remain disordered. Additionally, we have identified five flavonoids and one natural phenol rich in edible plants including fruits and vegetables, which inhibit Zika NS2B-NS3pro in a non-competitive mode, with Ki ranging from 770 nM for Myricetin to 34.02 μM for Apigenin. Molecular docking showed that they all bind to a pocket on the back of the active site and their structure-activity relationship was elucidated. Our study provides valuable insights into the solution conformation of Zika NS2B-NS3pro and further deciphers its susceptibility towards allosteric inhibition by natural products. As these natural product inhibitors fundamentally differ from the currently-known active site inhibitors in terms of both inhibitory mode and chemical scaffold, our finding might open a new avenue for development of better allosteric inhibitors to fight ZIKV infection.

  11. Data center network performance evaluation in ns3

    DEFF Research Database (Denmark)

    Andrus, Bogdan-Mihai; Vegas Olmos, Juan José

    2015-01-01

    In the following paper we present the analysis of highly interconnected topologies like hypercube and torus and how they can be implemented in data centers in order to cope with the rapid increase and demands for performance of the internal traffic. By replicating the topologies in NS3 and subjec......In the following paper we present the analysis of highly interconnected topologies like hypercube and torus and how they can be implemented in data centers in order to cope with the rapid increase and demands for performance of the internal traffic. By replicating the topologies in NS3...... we scale the network from 16 to 512 switches. The performance measurements are supported by abstract metrics that that also give a cost and complexity indication in choosing the right topology for the required application....

  12. Membranoproliferative glomerulonephritis and mixed cryoglobulinemia after hepatitis C virus infection secondary to glomerular NS3 viral antigen deposits.

    Science.gov (United States)

    Bataille, Stanislas; Kaplanski, Gilles; Boucraut, José; Halfon, Philippe; Camus, Claire; Daniel, Laurent; Burtey, Stéphane; Berland, Yvon; Dussol, Bertrand

    2012-01-01

    We report on 3 cases of membranoproliferative glomerulonephritis associated with mixed cryoglobulin in patients with hepatitis C virus (HCV) antibodies but a negative blood viral load. These cases explore the pathogenesis of the renal disease. We searched for occult HCV infection in peripheral blood mononuclear cells, cryoprecipitate, bone marrow cells, and glomeruli using ultrasensitive PCR assays and immunohistochemistry. We also looked for infraclinical B cell lymphoma by computed tomodensitometry, bone marrow aspiration and biopsy, and lymphocyte typing. By PCR assays, we did not evidence occult hepatitis C infection in peripheral blood mononuclear cells, bone marrow cells, or cryoprecipitates. In the only patient with available kidney specimen, we evidenced HCV-NS3 antigen in glomeruli. HCV-associated lymphoma was excluded, but mild polyclonal B lymphocytosis was present in the 3 patients. Remission occurred spontaneously in 1 patient, and in another patient it occurred after rituximab treatment. The third patient was lost to follow-up. In patients with hepatitis C-negative viral load, membranoproliferative glomerulonephritis could be induced by the persistence of HCV antigen in the kidney but not in hematopoietic cells. Nonlymphomatous B cell proliferation may also be induced by chronic viral stimulation. Copyright © 2012 S. Karger AG, Basel.

  13. In vitro inhibitory analysis of consensus siRNAs against NS3 gene of hepatitis C virus 1a genotype.

    Science.gov (United States)

    Shahid, Imran; AlMalki, Waleed Hassan; AlRabia, Mohammed Wanees; Mukhtar, Mohammed Hasan; Almalki, Shaia Saleh R; Alkahtani, Saad Ahmed; Ashgar, Sami S; Faidah, Hani S; Hafeez, Muhammad Hassan

    2017-07-01

    To explore inhibitory effects of genome-specific, chemically synthesized siRNAs (small interference RNA) against NS3 gene of hepatitis C virus (HCV) 1a genotype in stable Huh-7 (human hepatoma) cells as well as against viral replication in serum-inoculated Huh-7 cells. Stable Huh-7 cells persistently expressing NS3 gene were produced under antibiotic gentamycin (G418) selection. The cell clones resistant to 1000 μg antibiotic concentration (G418) were picked as stable cell clones. The NS3 gene expression in stable cell clone was confirmed by RT-PCR and Western blotting. siRNA cell cytotoxicity was determined by MTT cell proliferation assay. Stable cell lines were transfected with sequence specific siRNAs and their inhibitory effects were determined by RT-PCR, real-time PCR and Western blotting. The viral replication inhibition by siRNAs in serum inoculated Huh-7 cells was determined by real-time PCR. RT-PCR and Western blot analysis confirmed NS3 gene and protein expression in stable cell lines on day 10, 20 and 30 post transfection. MTT cell proliferation assay revealed that at most concentrated dose tested (50 nmol/L), siRNA had no cytotoxic effects on Huh-7 cells and cell proliferation remained unaffected. As demonstrated by the siRNA time-dependent inhibitory analysis, siRNA NS3-is44 showed maximum inhibition of NS3 gene in stable Huh-7 cell clones at 24 (80%, P = 0.013) and 48 h (75%, P = 0.002) post transfection. The impact of siRNAs on virus replication in serum inoculated Huh-7 cells also demonstrated significant decrease in viral copy number, where siRNA NS3-is44 exhibited 70% (P siRNA synergism (NS3-is33 + NS3-is44) decreased viral load by 84% (P siRNA (i.e., 64%-70% (P siRNAs mixture (NS5B-is88 + NS3-is33) targeting different region of HCV genome (NS5B and NS3) also decreased HCV viral load by 85% (P siRNA inhibitory effects alone (70% and 64% respectively, P siRNAs directed against NS3 gene significantly decreased mRNA and protein

  14. Identification and Analysis of Novel Inhibitors against NS3 Helicase and NS5B RNA-Dependent RNA Polymerase from Hepatitis C Virus 1b (Con1

    Directory of Open Access Journals (Sweden)

    Na Yang

    2017-11-01

    Full Text Available Hepatitis C virus (HCV leads to severe liver diseases, including liver fibrosis, cirrhosis and hepatocellular carcinoma. Non-structural protein 3 helicase (NS3h and non-structural protein 5B RNA-dependent RNA polymerase (NS5B are involved in the replication of HCV RNA genome, and have been proved to be excellent targets for discovery of direct-acting antivirals. In this study, two high-throughput screening systems, fluorescence polarization (FP-based ssDNA binding assay and fluorescence intensity (FI-based dsRNA formation assay, were constructed to identify candidate NS3h and NS5B inhibitors, respectively. A library of approximately 800 small molecules and crude extracts, derived from marine microorganisms or purchased from the National Compound Resource Center, China, were screened, with three hits selected for further study. Natural compound No.3A5, isolated from marine fungi, inhibited NS3h activity with an IC50 value of 2.8 μM. We further demonstrated that compound No.3A5 inhibited the abilities of NS3h to bind ssDNA in electrophoretic mobility shift assay and to hydrolyze ATP. The NS3h-inhibitory activity of compound No.3A5 was reversible in our dilution assay, which indicated there was no stable NS3h-No.3A5 complex formed. Additionally, compound No.3A5 exhibited no binding selectivity on NS3h or single strand binding protein of Escherichia coli. In NS5B assays, commercial compounds No.39 and No.94 previously reported as kinase inhibitors were found to disrupt dsRNA formation, and their IC50 values were 62.9 and 18.8 μM, respectively. These results highlight how identifying new uses for existing drugs is an effective method for discovering novel HCV inhibitors. To our knowledge, all inhibitors reported in this study were originally discovered with HCV anti-non-structural protein activities in vitro.

  15. Molecular Dynamics of the ZIKA Virus NS3 Helicase

    Science.gov (United States)

    Raubenolt, Bryan; Rick, Steven; The Rick Group Team

    The recent outbreaks of the ZIKA virus (ZIKV) and its connection to microcephaly in newborns has raised its awareness as a global threat and many scientific research efforts are currently underway in attempt to create a vaccine. Molecular Dynamics is a powerful method of investigating the physical behavior of protein complexes. ZIKV is comprised of 3 structural and 7 nonstructural proteins. The NS3 helicase protein appears to play a significant role in the replication complex and its inhibition could be a crucial source of antiviral drug design. This research primarily focuses on studying the structural dynamics, over the course of few hundred nanoseconds, of NS3 helicase in the free state, as well as in complex form with human ssRNA, ATP, and an analogue of GTP. RMSD and RMSF plots of each simulation will provide details on the forces involved in the overall stability of the active and inactive states. Furthermore, free energy calculations on a per residue level will reveal the most interactive residues between states and ultimately the primary driving force behind these interactions. Together these analyses will provide highly relevant information on the binding surface chemistry and thus serve as the basis for potential drug design.

  16. Broadening CD4(+) and CD8(+) T Cell Responses against Hepatitis C Virus by Vaccination with NS3 Overlapping Peptide Panels in Cross-Priming Liposomes

    DEFF Research Database (Denmark)

    Filskov, Jonathan; Mikkelsen, Marianne; Hansen, Paul R.

    2017-01-01

    Despite the introduction of effective drugs to treat patients with chronic hepatitis C virus (HCV) infection, a vaccine would be the only means to substantially reduce the worldwide disease burden. An incomplete understanding of how HCV interacts with its human host and evades immune surveillance...... and was as potent a CD8+ T cell inducer as an adenovirus-vectored vaccine expressing NS3. Importantly, the cellular responses are dominated by multifunctional T cells, such as gamma interferon-positive (IFN-γ+) tumor necrosis factor alpha-positive (TNF-α+) coproducers, and displayed cytotoxic capacity in mice...

  17. VP2-serotyped live-attenuated bluetongue virus without NS3/NS3a expression provides serotype-specific protection and enables DIVA.

    Science.gov (United States)

    Feenstra, Femke; Maris-Veldhuis, Mieke; Daus, Franz J; Tacken, Mirriam G J; Moormann, Rob J M; van Gennip, René G P; van Rijn, Piet A

    2014-12-12

    Bluetongue virus (BTV) causes Bluetongue in ruminants and is transmitted by Culicoides biting midges. Vaccination is the most effective measure to control vector borne diseases; however, there are 26 known BTV serotypes showing little cross protection. The BTV serotype is mainly determined by genome segment 2 encoding the VP2 protein. Currently, inactivated and live-attenuated Bluetongue vaccines are available for a limited number of serotypes, but each of these have their specific disadvantages, including the inability to differentiate infected from vaccinated animals (DIVA). BTV non-structural proteins NS3 and NS3a are not essential for virus replication in vitro, but are important for cytopathogenic effect in mammalian cells and for virus release from insect cells in vitro. Recently, we have shown that virulent BTV8 without NS3/NS3a is non-virulent and viremia in sheep is strongly reduced, whereas local in vivo replication leads to seroconversion. Live-attenuated BTV6 without NS3/NS3a expression protected sheep against BTV challenge. Altogether, NS3/NS3a knockout BTV6 is a promising vaccine candidate and has been named Disabled Infectious Single Animal (DISA) vaccine. Here, we show serotype-specific protection in sheep by DISA vaccine in which only genome segment 2 of serotype 8 was exchanged. Similarly, DISA vaccines against other serotypes could be developed, by exchange of only segment 2, and could therefore safely be combined in multi-serotype cocktail vaccines with respect to reassortment between vaccine viruses. Additionally, NS3 antibody responses are raised after natural BTV infection and NS3-based ELISAs are therefore appropriate tools for DIVA testing accompanying the DISA vaccine. To enable DIVA, we developed an experimental NS3 ELISA. Indeed, vaccinated sheep remained negative for NS3 antibodies, whereas seroconversion for NS3 antibodies was associated with viremia after heterologous BTV challenge. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Rapid emergence of hepatitis C virus protease inhibitor resistance is expected

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Libin [Los Alamos National Laboratory; Perelson, Alan S [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory

    2009-01-01

    Approximately 170 million people worldwide are infected with hepatitis C virus (HCV). Current therapy, consisting of pegylated interferon (PEG-IFN) and ribavirin (RBV), leads to sustained viral elimination in only about 45% of patients treated. Telaprevir (VX-950), a novel HCV NS3-4A serine protease inhibitor, has demonstrated substantial antiviral activity in patients with chronic hepatitis C genotype 1 infection. However, some patients experience viral breakthrough during dosing, with drug resistant variants being 5%-20% of the virus population as early as day 2 after treatment initiation. Why viral variants appear such a short time after the start of dosing is unclear, especially since this has not been seen with monotherapy for either human immunodeficiency virus or hepatitis B virus. Here, using a viral dynamic model, we explain why such rapid emergence of drug resistant variants is expected when potent HCV protease inhibitors are used as monotherapy. Surprisingly, our model also shows that such rapid emergence need not be the case with some potent HCV NS5B polymerase inhibitors. Examining the case of telaprevir therapy in detail, we show the model fits observed dynamics of both wild-type and drug-resistant variants during treatment, and supports combination therapy of direct antiviral drugs with PEG-IFN and/or RBV for hepatitis C.

  19. Solution conformations of Zika NS2B-NS3pro and its inhibition by natural products from edible plants.

    Directory of Open Access Journals (Sweden)

    Amrita Roy

    Full Text Available The recent Zika viral (ZIKV epidemic has been associated with severe neurological pathologies such as neonatal microcephaly and Guillain-Barre syndrome but unfortunately no vaccine or medication is effectively available yet. Zika NS2B-NS3pro is essential for the proteolysis of the viral polyprotein and thereby viral replication. Thus NS2B-NS3pro represents an attractive target for anti-Zika drug discovery/design. Here, we have characterized the solution conformations and catalytic parameters of both linked and unlinked Zika NS2B-NS3pro complexes and found that the unlinked complex manifested well-dispersed NMR spectra. Subsequently with selective isotope-labeling using NMR spectroscopy, we demonstrated that C-terminal residues (R73-K100 of NS2B is highly disordered without any stable tertiary and secondary structures in the Zika NS2B-NS3pro complex in the free state. Upon binding to the well-characterized serine protease inhibitor, bovine pancreatic trypsin inhibitor (BPTI, only the extreme C-terminal residues (L86-K100 remain disordered. Additionally, we have identified five flavonoids and one natural phenol rich in edible plants including fruits and vegetables, which inhibit Zika NS2B-NS3pro in a non-competitive mode, with Ki ranging from 770 nM for Myricetin to 34.02 μM for Apigenin. Molecular docking showed that they all bind to a pocket on the back of the active site and their structure-activity relationship was elucidated. Our study provides valuable insights into the solution conformation of Zika NS2B-NS3pro and further deciphers its susceptibility towards allosteric inhibition by natural products. As these natural product inhibitors fundamentally differ from the currently-known active site inhibitors in terms of both inhibitory mode and chemical scaffold, our finding might open a new avenue for development of better allosteric inhibitors to fight ZIKV infection.

  20. Investigation of the effect of food and omeprazole on the relative bioavailability of a single oral dose of 240 mg faldaprevir, a selective inhibitor of HCV NS3/4 protease, in an open-label, randomized, three-way cross-over trial in healthy participants.

    Science.gov (United States)

    Wu, Jing; Gießmann, Thomas; Lang, Benjamin; Elgadi, Mabrouk; Huang, Fenglei

    2016-04-01

    This study was conducted to investigate the effect of food and coadministration of omeprazole on the relative bioavailability (BA) of faldaprevir (FDV). Fifteen healthy participants participated in this open-label, randomized, three-way cross-over study. Faldaprevir was administered as a 240 mg single dose during fasting state, following intake of a high-fat breakfast, or following omeprazole 40 mg q.d. dosing for 5 days. PK samples were collected on the day of faldaprevir administration. We found geometric mean (gMean) AUC0-∞ values for faldaprevir of 48 200, 37 900 and 36 000 ng h/ml under the fed, fasted and omeprazole coadministration conditions respectively. Similarly, gMean Cmax values for faldaprevir were 2600, 2030, 1920 ng/ml under the same respective conditions. The adjusted gMean ratio between the fed and fasted condition was approximately 120% for both AUC0-∞ and Cmax , while the ratio of omeprazole coadministration to fasted condition was approximately 94%. Faldaprevir was safe and well tolerated in the study. Administration of a single dose of 240 mg faldaprevir after high-fat breakfast led to a modest, clinically irrelevant increase in faldaprevir exposure, while coadministration of omeprazole did not influence faldaprevir exposure. © 2016 Royal Pharmaceutical Society, Journal of Pharmacy and Pharmacology.

  1. Specific Detection of Naturally Occurring Hepatitis C Virus Mutants with Resistance to Telaprevir and Boceprevir (Protease Inhibitors) among Treatment-Naïve Infected Individuals

    Science.gov (United States)

    Fonseca-Coronado, Salvador; Escobar-Gutiérrez, Alejandro; Ruiz-Tovar, Karina; Cruz-Rivera, Mayra Yolanda; Rivera-Osorio, Pilar; Vazquez-Pichardo, Mauricio; Carpio-Pedroza, Juan Carlos; Ruíz-Pacheco, Juan Alberto; Cazares, Fernando

    2012-01-01

    The use of telaprevir and boceprevir, both protease inhibitors (PI), as part of the specifically targeted antiviral therapy for hepatitis C (STAT-C) has significantly improved sustained virologic response (SVR) rates. However, different clinical studies have also identified several mutations associated with viral resistance to both PIs. In the absence of selective pressure, drug-resistant hepatitis C virus (HCV) mutants are generally present at low frequency, making mutation detection challenging. Here, we describe a mismatch amplification mutation assay (MAMA) PCR method for the specific detection of naturally occurring drug-resistant HCV mutants. MAMA PCR successfully identified the corresponding HCV variants, while conventional methods such as direct sequencing, endpoint limiting dilution (EPLD), and bacterial cloning were not sensitive enough to detect circulating drug-resistant mutants in clinical specimens. Ultradeep pyrosequencing was used to confirm the presence of the corresponding HCV mutants. In treatment-naïve patients, the frequency of all resistant variants was below 1%. Deep amplicon sequencing allowed a detailed analysis of the structure of the viral population among these patients, showing that the evolution of the NS3 is limited to a rather small sequence space. Monitoring of HCV drug resistance before and during treatment is likely to provide important information for management of patients undergoing anti-HCV therapy. PMID:22116161

  2. Ledipasvir-sofosbuvir with or without ribavirin to treat patients with HCV genotype 1 infection and cirrhosis non-responsive to previous protease-inhibitor therapy: a randomised, double-blind, phase 2 trial (SIRIUS).

    Science.gov (United States)

    Bourlière, Marc; Bronowicki, Jean-Pierre; de Ledinghen, Victor; Hézode, Christophe; Zoulim, Fabien; Mathurin, Philippe; Tran, Albert; Larrey, Dominique G; Ratziu, Vlad; Alric, Laurent; Hyland, Robert H; Jiang, Deyuan; Doehle, Brian; Pang, Phillip S; Symonds, William T; Subramanian, G Mani; McHutchison, John G; Marcellin, Patrick; Habersetzer, François; Guyader, Dominique; Grangé, Jean-Didier; Loustaud-Ratti, Véronique; Serfaty, Lawrence; Metivier, Sophie; Leroy, Vincent; Abergel, Armand; Pol, Stanislas

    2015-04-01

    Patients with cirrhosis resulting from chronic hepatitis C virus (HCV) infection are at risk of life-threatening complications, but consistently achieve lower sustained virological response (SVR) than patients without cirrhosis, especially if treatment has previously failed. We assessed the efficacy and safety of the NS5A inhibitor ledipasvir and the nucleotide polymerase inhibitor sofosbuvir, with and without ribavirin. In this multicentre, double-blind trial, between Oct 21, 2013, and Oct 30, 2014, we enrolled patients with HCV genotype 1 and compensated cirrhosis who had not achieved SVR after successive treatments with pegylated interferon and protease-inhibitor regimens at 20 sites in France. With a computer-generated randomisation sequence, patients were assigned in a 1:1 ratio to receive placebo matched in appearance to study drugs for 12 weeks followed by once daily combination fixed-dose tablets of 90 mg ledipasvir and 400 mg sofosbuvir plus weight-based ribavirin for 12 weeks, or ledipasvir-sofosbuvir plus placebo once daily for 24 weeks. The primary endpoint was SVR 12 weeks after the end of treatment (SVR12), for which 95% CIs were calculated with the Clopper-Pearson method. This study is registered with ClinicalTrials.gov, number NCT01965535. Of 172 patients screened, 155 entered randomisation, 77 were assigned to receive ledipasvir-sofosbuvir plus ribavirin and 78 ledipasvir-sofosbuvir. 114 (74%) were men, 151 (97%), were white, 98 (63%) had HCV genotype 1a, and 145 (94%) had non-CC IL28B alleles. SVR12 rates were 96% (95% CI 89-99) for patients in the ledipasvir-sofosbuvir plus ribavirin group and 97% (91-100) in the ledipasvir-sofosbuvir group. One patient discontinued treatment because of adverse events while receiving only placebo. The most frequent adverse events were asthenia and headache, pruritus, and fatigue. Ledipasvir-sofosbuvir plus ribavirin for 12 weeks and ledipasvir-sofosbuvir for 24 weeks provided similarly high SVR12 rates in

  3. Sustained specific and cross-reactive T cell responses to Zika and Dengue viruses NS3 in West Africa.

    Science.gov (United States)

    Herrera, Bobby Brooke; Tsai, Wen-Yang; Chang, Charlotte A; Hamel, Donald J; Wang, Wei-Kung; Lu, Yichen; Mboup, Souleymane; Kanki, Phyllis J

    2018-01-10

    Recent studies on the role of T cells in Zika virus (ZIKV) infection have shown that T cell responses to Asian ZIKV infection are important for protection, and that previous Dengue virus (DENV) exposure amplifies the protective T cell response to Asian ZIKV. Human T cell responses to African ZIKV infection, however, remain unexplored. Here, we utilized the modified anthrax toxin delivery system to develop a flavivirus ELISPOT. Using human ZIKV and DENV samples from Senegal, West Africa, our results demonstrate specific and cross-reactive T cell responses to nonstructural protein 3 (NS3). Specifically, we found that T cell responses to NS3 protease are ZIKV and DENV specific, but responses to NS3 helicase are cross-reactive. Sequential sample analyses revealed immune responses sustained many years after infection. These results have important implications for African ZIKV/DENV vaccine development, as well for potential flavivirus diagnostics based on T cell responses.IMPORTANCEThe recent Zika virus (ZIKV) epidemic in Latin America and the associated congenital microcephaly and Guillain-Barré syndrome has raised questions as to why we have not recognized these distinct clinical diseases in Africa. The human immunologic response to ZIKV and related flaviviruses in Africa represents a research gap that may potentially shed light on the mechanisms contributing to protection. The goal of our study was to develop an inexpensive assay to detect and characterize the T cell response to African ZIKV and DENV. Our data show long-term specific and cross-reactive human immune responses against African ZIKV and DENV, suggesting the potential usefulness of a diagnostic based on the T cell response. Additionally, we show that prior flavivirus exposure influences the magnitude of the T cell response. The identification of immune responses to African ZIKV and DENV is of relevance to vaccine development. Copyright © 2018 American Society for Microbiology.

  4. Efficient hepatitis c virus genotype 1b core-NS5A recombinants permit efficacy testing of protease and NS5A inhibitors

    DEFF Research Database (Denmark)

    Pham, Long V.; Ramirez Almeida, Santseharay; Carlsen, Thomas H R

    2017-01-01

    Hepatitis C virus (HCV) strains belong to seven genotypes with numerous subtypes that respond differently to antiviral therapies. Genotype 1, and primarily subtype 1b, is the most prevalent genotype worldwide. The development of recombinant HCV infectious cell culture systems for different variants...... cell culture adaptive substitutions A1226G, R1496L, and Q1773H. These viruses spread efficiently in Huh7.5 cells by acquiring additional adaptive substitutions, and final recombinants yielded peak supernatant infectivity titers of 4 to 5 log10 focus-forming units (FFU)/ml. We subsequently succeeded...... in adapting a JFH1- based 5=UTR-NS5A DH1 recombinant to efficient growth in cell culture. We evaluated the efficacy of clinically relevant NS3/4A protease and NS5A inhibitors against the novel genotype 1b viruses, as well as against previously developed 1a viruses. The inhibitors were efficient against all...

  5. Strong vaccine-induced CD8 T-cell responses have cytolytic function in a chimpanzee clearing HCV infection

    NARCIS (Netherlands)

    B.E. Verstrepen (Babs); E.J. Verschoor (Ernst); Z. Fagrouch (Zahra); P. Mooij (Petra); N.G. Groot (Natasja); R.E. Bontrop (Ronald ); W. Bogers (Willy); J.L. Heeney (Jonathan); G. Koopman (Gerrit)

    2014-01-01

    textabstractA single correlate of effective vaccine protection against chronic HCV infection has yet to be defined. In this study, we analyzed T-cell responses in four chimpanzees, immunized with core-E1-E2-NS3 and subsequently infected with HCV1b. Viral clearance was observed in one animal, while

  6. Hepatitis C Virus NS3 Mediated Microglial Inflammation via TLR2/TLR6 MyD88/NF-κB Pathway and Toll Like Receptor Ligand Treatment Furnished Immune Tolerance.

    Directory of Open Access Journals (Sweden)

    Ayilam Ramachandran Rajalakshmy

    Full Text Available Recent evidence suggests the neurotrophic potential of hepatitis C virus (HCV. HCV NS3 protein is one of the potent antigens of this virus mediating inflammatory response in different cell types. Microglia being the immune surveillance cells in the central nervous system (CNS, the inflammatory potential of NS3 on microglia was studied. Role of toll like receptor (TLR ligands Pam2CSK3 and Pam3CSK4 in controlling the NS3 mediated microglial inflammation was studied using microglial cell line CHME3.IL (Interleukin-8, IL-6, TNF-α (Tumor nicrosis factor alpha and IL-1β gene expressions were measured by semi quantitative RT-PCR (reverse transcription-PCR. ELISA was performed to detect IL-8, IL-6, TNF-α, IL-1β and IL-10 secretion. FACS (Flourescent activated cell sorting was performed to quantify TLR1, TLR2, TLR6, MyD88 (Myeloid differntiation factor 88, IkB-α (I kappaB alpha and pNF-κB (phosphorylated nuclear factor kappaB expression. Immunofluorescence staining was performed for MyD88, TLR6 and NF-κB (Nuclear factor kappaB. Student's t-test or One way analysis of variance with Bonferoni post hoc test was performed and p < 0.05 was considered significant.Microglia responded to NS3 by secreting IL-8, IL-6, TNF-α and IL-1β via TLR2 or TLR6 mediated MyD88/NF-κB pathway. Transcription factor NF-κB was involved in activating the cytokine gene expression and the resultant inflammatory response was controlled by NF-κB inhibitor, Ro106-9920, which is known to down regulate pro-inflammatory cytokine secretion. Activation of the microglia by TLR agonists Pam3CSK4 and Pam2CSK4 induced immune tolerance against NS3. TLR ligand treatment significantly down regulated pro-inflammatory cytokine secretion in the microglia. IL-10 secretion was suggested as the possible mechanism by which TLR agonists induced immune tolerance. NS3 as such was not capable of self-inducing immune tolerance in microglia.In conclusion, NS3 protein was capable of activating

  7. Targeting Dengue Virus NS-3 Helicase by Ligand based Pharmacophore Modeling and Structure based Virtual Screening

    Directory of Open Access Journals (Sweden)

    Sobia A. Halim

    2017-10-01

    Full Text Available Dengue fever is an emerging public health concern, with several million viral infections occur annually, for which no effective therapy currently exist. Non-structural protein 3 (NS-3 Helicase encoded by the dengue virus (DENV is considered as a potential drug target to design new and effective drugs against dengue. Helicase is involved in unwinding of dengue RNA. This study was conducted to design new NS-3 Helicase inhibitor by in silico ligand- and structure based approaches. Initially ligand-based pharmacophore model was generated that was used to screen a set of 1201474 compounds collected from ZINC Database. The compounds matched with the pharmacophore model were docked into the active site of NS-3 helicase. Based on docking scores and binding interactions, 25 compounds are suggested to be potential inhibitors of NS3 Helicase. The pharmacokinetic properties of these hits were predicted. The selected hits revealed acceptable ADMET properties. This study identified potential inhibitors of NS-3 Helicase in silico, and can be helpful in the treatment of Dengue.

  8. Hepatitis C virus (HCV): ever in reliable partnerships?

    African Journals Online (AJOL)

    GRACE

    2006-06-16

    Jun 16, 2006 ... hemophiliacs, multiple changes in HCV genotypes were observed in 58 % of the subjects, over a 3–15- ..... increase in HCV RNA levels in hemophiliacs (Eyster et. Amoador-Canizares and Duenas-Carrera .... and colleagues results showed that, among women who continued to receive protease inhibitors ...

  9. Anticuerpos policlonales contra la proteína recombinante NS3 del virus del dengue

    Directory of Open Access Journals (Sweden)

    Liliana Morales

    2017-01-01

    Resultados. Los anticuerpos producidos fueron útiles en ensayos de Western blot e inmunofluorescencia y se reportó por primera vez un anticuerpo policlonal anti-NS3 que permitió la inmunoprecipitación de la proteína viral y la detecta con Western blot sin necesidad de inducir sobreexpresión de NS3 o de usar extractos de células marcados metabólicamente con radioisótopos. Conclusión. Las proteínas recombinantes expresadas y los anticuerpos producidos constituyen herramientas valiosas para estudiar procesos infecciosos del DENV que involucren a la proteína NS3 y evaluar pruebas dirigidas a interferir las funciones de esta proteína.

  10. Three Conformational Snapshots of the Hepatitis Virus NS3 Helicase Reveal a Ratchet Translocation Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Gu, M.; Rice, C

    2010-01-01

    A virally encoded superfamily-2 (SF2) helicase (NS3h) is essential for the replication of hepatitis C virus, a leading cause of liver disease worldwide. Efforts to elucidate the function of NS3h and to develop inhibitors against it, however, have been hampered by limited understanding of its molecular mechanism. Here we show x-ray crystal structures for a set of NS3h complexes, including ground-state and transition-state ternary complexes captured with ATP mimics (ADP {center_dot} BeF{sub 3} and ADP {center_dot} AlF{sub 4}{sup -}). These structures provide, for the first time, three conformational snapshots demonstrating the molecular basis of action for a SF2 helicase. Upon nucleotide binding, overall domain rotation along with structural transitions in motif V and the bound DNA leads to the release of one base from the substrate base-stacking row and the loss of several interactions between NS3h and the 3{prime} DNA segment. As nucleotide hydrolysis proceeds into the transition state, stretching of a 'spring' helix and another overall conformational change couples rearrangement of the (d)NTPase active site to additional hydrogen-bonding between NS3h and DNA. Together with biochemistry, these results demonstrate a 'ratchet' mechanism involved in the unidirectional translocation and define the step size of NS3h as one base per nucleotide hydrolysis cycle. These findings suggest feasible strategies for developing specific inhibitors to block the action of this attractive, yet largely unexplored drug target.

  11. Efficacy of 8 Weeks of Sofosbuvir, Velpatasvir, and Voxilaprevir in Patients With Chronic HCV Infection: 2 Phase 3 Randomized Trials.

    Science.gov (United States)

    Jacobson, Ira M; Lawitz, Eric; Gane, Edward J; Willems, Bernard E; Ruane, Peter J; Nahass, Ronald G; Borgia, Sergio M; Shafran, Stephen D; Workowski, Kimberly A; Pearlman, Brian; Hyland, Robert H; Stamm, Luisa M; Svarovskaia, Evguenia; Dvory-Sobol, Hadas; Zhu, Yanni; Subramanian, G Mani; Brainard, Diana M; McHutchison, John G; Bräu, Norbert; Berg, Thomas; Agarwal, Kosh; Bhandari, Bal Raj; Davis, Mitchell; Feld, Jordan J; Dore, Gregory J; Stedman, Catherine A M; Thompson, Alexander J; Asselah, Tarik; Roberts, Stuart K; Foster, Graham R

    2017-07-01

    Patients with chronic hepatitis C virus (HCV) infection have high rates of sustained virologic response (SVR) after 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir combined with the NS5A inhibitor velpatasvir. We assessed the efficacy of 8 weeks of treatment with sofosbuvir and velpatasvir plus the pangenotypic NS3/4A protease inhibitor voxilaprevir (sofosbuvir-velpatasvir-voxilaprevir). In 2 phase 3, open-label trials, patients with HCV infection who had not been treated previously with a direct-acting antiviral agent were assigned randomly to groups given sofosbuvir-velpatasvir-voxilaprevir for 8 weeks or sofosbuvir-velpatasvir for 12 weeks. POLARIS-2, which enrolled patients infected with all HCV genotypes with or without cirrhosis, except patients with genotype 3 and cirrhosis, was designed to test the noninferiority of 8 weeks of sofosbuvir-velpatasvir-voxilaprevir to 12 weeks of sofosbuvir-velpatasvir using a noninferiority margin of 5%. POLARIS-3, which enrolled patients infected with HCV genotype 3 who had cirrhosis, compared rates of SVR in both groups with a performance goal of 83%. In POLARIS-2, 95% (95% confidence interval [CI], 93%-97%) of patients had an SVR to 8 weeks of sofosbuvir-velpatasvir-voxilaprevir; this did not meet the criterion to establish noninferiority to 12 weeks of sofosbuvir-velpatasvir, which produced an SVR in 98% of patients (95% CI, 96%-99%; difference in the stratum-adjusted Mantel-Haenszel proportions of -3.2%; 95% CI, -6.0% to -0.4%). The difference in the efficacy was owing primarily to a lower rate of SVR (92%) among patients with HCV genotype 1a infection receiving 8 weeks of sofosbuvir-velpatasvir-voxilaprevir. In POLARIS-3, 96% of patients (95% CI, 91%-99%) achieved an SVR in both treatment groups, which was significantly superior to the performance goal. Overall, the most common adverse events were headache, fatigue, diarrhea, and nausea; diarrhea and nausea were reported more frequently by

  12. Interferon-Free Hepatitis C Treatment before and after Liver Transplantation: The Role of HCV Drug Resistance

    Directory of Open Access Journals (Sweden)

    Bruno Roche

    2015-09-01

    Full Text Available Hepatitis C virus (HCV infection is one of the leading causes of end-stage liver disease and the main indication for liver transplantation (LT in most countries. All patients who undergo LT with detectable serum HCV RNA experience graft reinfection progressing to cirrhosis within five years in 20% to 30% of them. Obtaining a sustained virological response (SVR greatly improves overall and graft survival. Until 2011, standard antiviral therapy using PEGylated interferon (PEG-IFN and ribavirin (RBV was the only effective therapy, with an SVR rate around 30% in this setting. For patients infected with genotype 1, first generation NS3/4A protease inhibitors (PIs, boceprevir (BOC or telaprevir (TVR, associated with PEG-IFN and RBV for 48 weeks have increased the SVR rates to 60% in non-transplant patients. However, tolerability and drug-drug interactions with calcineurin inhibitors (CNI are both limiting factors of their use in the liver transplant setting. Over recent years, the efficacy of antiviral C therapy has improved dramatically using new direct-acting antiviral (DAA agents without PEG-IFN and/or RBV, leading to SVR rates over 90% in non-transplant patients. Results available for transplant patients showed a better efficacy and tolerability and less drug-drug interactions than with first wave PIs. However, some infrequent cases of viral resistance have been reported using PIs or NS5A inhibitors pre- or post-LT that can lead to difficulties in the management of these patients.

  13. The NS3 protein of rice hoja blanca virus suppresses RNA silencing in mammalian cells

    NARCIS (Netherlands)

    Schnettler, E.; Hemmes, J.C.; Goldbach, R.W.; Prins, M.W.

    2008-01-01

    The NS3 protein of the tenuivirus rice hoja blanca virus (RHBV) has previously been shown to represent the viral RNA interference (RNAi) suppressor and is active in both plant and insect cells by binding short interfering RNAs (siRNAs) in vitro. Using a firefly luciferase-based silencing assay it is

  14. NS2 Proteins of GB Virus B and Hepatitis C Virus Share Common Protease Activities and Membrane Topologies

    Science.gov (United States)

    Boukadida, Célia; Marnata, Caroline; Montserret, Roland; Cohen, Lisette; Blumen, Brigitte; Gouttenoire, Jérôme; Moradpour, Darius; Penin, François

    2014-01-01

    ABSTRACT GB virus B (GBV-B), which is hepatotropic in experimentally infected small New World primates, is a member of the Hepacivirus genus but phylogenetically relatively distant from hepatitis C virus (HCV). To gain insights into the role and specificity of hepaciviral nonstructural protein 2 (NS2), which is required for HCV polyprotein processing and particle morphogenesis, we investigated whether NS2 structural and functional features are conserved between HCV and GBV-B. We found that GBV-B NS2, like HCV NS2, has cysteine protease activity responsible for cleavage at the NS2/NS3 junction, and we experimentally confirmed the location of this junction within the viral polyprotein. A model for GBV-B NS2 membrane topology was experimentally established by determining the membrane association properties of NS2 segments fused to green fluorescent protein (GFP) and their nuclear magnetic resonance structures using synthetic peptides as well as by applying an N-glycosylation scanning approach. Similar glycosylation studies confirmed the HCV NS2 organization. Together, our data show that despite limited amino acid sequence similarity, GBV-B and HCV NS2 proteins share a membrane topology with 3 N-terminal transmembrane segments, which is also predicted to apply to other recently discovered hepaciviruses. Based on these data and using trans-complementation systems, we found that intragenotypic hybrid NS2 proteins with heterologous N-terminal membrane segments were able to efficiently trans-complement an assembly-deficient HCV mutant with a point mutation in the NS2 C-terminal domain, while GBV-B/HCV or intergenotypic NS2 chimeras were not. These studies indicate that virus- and genotype-specific intramolecular interactions between N- and C-terminal domains of NS2 are critically involved in HCV morphogenesis. IMPORTANCE Nonstructural protein 2 (NS2) of hepatitis C virus (HCV) is a multifunctional protein critically involved in polyprotein processing and virion

  15. Binding by the hepatitis C virus NS3 helicase partially melts duplex DNA.

    Science.gov (United States)

    Raney, Veronica M; Reynolds, Kimberly A; Harrison, Melody K; Harrison, David K; Cameron, Craig E; Raney, Kevin D

    2012-09-25

    Binding of NS3 helicase to DNA was investigated by footprinting with KMnO(4), which reacts preferentially with thymidine residues in single-stranded DNA (ssDNA) compared to those in double-stranded DNA (dsDNA). A distinct pattern of reactivity was observed on ssDNA, which repeated every 8 nucleotides (nt) and is consistent with the known binding site size of NS3. Binding to a DNA substrate containing a partial duplex was also investigated. The DNA contained a 15 nt overhang made entirely of thymidine residues adjacent to a 22 bp duplex that contained thymidine at every other position. Surprisingly, the KMnO(4) reactivity pattern extended from the ssDNA into the dsDNA region of the substrate. Lengthening the partial duplex to 30 bp revealed a similar pattern extending from the ssDNA into the dsDNA, indicating that NS3 binds within the duplex region. Increasing the length of the ssDNA portion of the partial duplex by 4 nt resulted in a shift in the footprinting pattern for the ssDNA by 4 nt, which is consistent with binding to the 3'-end of the ssDNA. However, the footprinting pattern in the dsDNA region was shifted by only 1-2 bp, indicating that binding to the ssDNA-dsDNA region was preferred. Footprinting performed as a function of time indicated that NS3 binds to the ssDNA rapidly, followed by slower binding to the duplex. Hence, multiple molecules of NS3 can bind along a ssDNA-dsDNA partial duplex by interacting with the ssDNA as well as the duplex DNA.

  16. Daclatasvir and asunaprevir plus peginterferon alfa and ribavirin in HCV genotype 1 or 4 non-responders.

    Science.gov (United States)

    Jensen, Donald; Sherman, Kenneth E; Hézode, Christophe; Pol, Stanislas; Zeuzem, Stefan; de Ledinghen, Victor; Tran, Albert; Elkhashab, Magdy; Younes, Ziad H; Kugelmas, Marcelo; Mauss, Stefan; Everson, Gregory; Luketic, Velimir; Vierling, John; Serfaty, Lawrence; Brunetto, Maurizia; Heo, Jeong; Bernstein, David; McPhee, Fiona; Hennicken, Delphine; Mendez, Patricia; Hughes, Eric; Noviello, Stephanie

    2015-07-01

    Improved therapies for peginterferon/ribavirin null or partial responders are needed. This study evaluated daclatasvir (NS5A inhibitor) and asunaprevir (NS3 protease inhibitor) plus peginterferon alfa-2a and ribavirin in this patient population. This open-label, phase 3 study (HALLMARK-QUAD; NCT01573351) treated patients with chronic hepatitis C virus (HCV) genotype 1 (n=354) or 4 (n=44) infection who had a prior null or partial response to peginterferon/ribavirin. Patients received daclatasvir 60 mg once-daily plus asunaprevir 100mg twice-daily, with weekly peginterferon alfa-2a and weight-based ribavirin for 24 weeks. The primary endpoint was sustained virological response at post-treatment week 12 (SVR12) among genotype 1-infected patients. Daclatasvir plus asunaprevir and peginterferon/ribavirin demonstrated SVR12 rates of 93% (95% CI 90-96) in prior non-responders infected with HCV genotype 1. SVR12 rates among genotype 4-infected patients were 98% (95% CI 93-100); one patient had a missing post-treatment week-12 HCV-RNA measurement, but achieved an SVR at post-treatment week 24, yielding a 100% SVR rate in genotype 4 patients. Prior peginterferon/ribavirin response, sex, age, IL28B genotype, or cirrhosis status did not influence SVR12 rates. Serious adverse events occurred in 6% of patients; 5% discontinued treatment due to an adverse event. Grade 3/4 laboratory abnormalities included neutropenia (22%), lymphopenia (16%), anemia (6%), thrombocytopenia (4%), and ALT/AST elevations (3% each). Daclatasvir plus asunaprevir and peginterferon/ribavirin demonstrated high rates of SVR12 in genotype 1- or 4-infected prior null or partial responders. The combination was well tolerated and no additional safety and tolerability concerns were observed compared with peginterferon/ribavirin regimens. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  17. Asunaprevir, a protease inhibitor for the treatment of hepatitis C infection

    Directory of Open Access Journals (Sweden)

    Gentile I

    2014-06-01

    , asunaprevir is associated with a transient increase in aminotransferase levels, which is mild in most cases. In conclusion, asunaprevir is a good candidate component of interferon-free combinations and may revolutionize the treatment of chronic HCV infection in the near future. Keywords: NS3, interferon, ribavirin, interferon-free, daclatasvir, sofosbuvir

  18. Simulación de redes móviles ad hoc mediante ns-3

    OpenAIRE

    Yuste Delgado, Antonio

    2014-01-01

    Introducción a la herramienta de simulación de redes network simulator 3 (ns-3). Este simulador es una de los programas más utilizados en la actualidad para la simulación de redes de diversos tipos, desde las redes ad hoc a redes móviles. El profesor Antonio Yuste especialista en protocolos de enrutamiento en redes móviles ad hoc utiliza este software en sus simulaciones. El objetivo de la charla es una dar una visión general del simulador y explicarnos cómo simular redes ad hoc móviles. U...

  19. Adapted J6/JFH1-Based Hepatitis C Virus Recombinants with Genotype-Specific NS4A Show Similar Efficacies against Lead Protease Inhibitors, Alpha Interferon, and a Putative NS4A Inhibitor

    Science.gov (United States)

    Gottwein, Judith M.; Jensen, Sanne B.; Serre, Stéphanie B. N.; Ghanem, Lubna; Scheel, Troels K. H.; Jensen, Tanja B.; Krarup, Henrik; Uzcategui, Nathalie; Mikkelsen, Lotte S.

    2013-01-01

    To facilitate studies of hepatitis C virus (HCV) NS4A, we aimed at developing J6/JFH1-based recombinants with genotype 1- to 7-specific NS4A proteins. We developed efficient culture systems expressing NS4A proteins of genotypes (isolates) 1a (H77 and TN), 1b (J4), 2a (J6), 4a (ED43), 5a (SA13), 6a (HK6a), and 7a (QC69), with peak infectivity titers of ∼3.5 to 4.5 log10 focus-forming units per ml. Except for genotype 2a (J6), growth depended on adaptive mutations identified in long-term culture. Genotype 1a, 1b, and 4a recombinants were adapted by amino acid substitutions F772S (p7) and V1663A (NS4A), while 5a, 6a, and 7a recombinants required additional substitutions in the NS3 protease and/or NS4A. We demonstrated applicability of the developed recombinants for study of antivirals. Genotype 1 to 7 NS4A recombinants showed similar responses to the protease inhibitors telaprevir (VX-950), boceprevir (Sch503034), simeprevir (TMC435350), danoprevir (ITMN-191), and vaniprevir (MK-7009), to alpha interferon 2b, and to the putative NS4A inhibitor ACH-806. The efficacy of ACH-806 was lower than that of protease inhibitors and was not influenced by changes at amino acids 1042 and 1065 (in the NS3 protease), which have been suggested to mediate resistance to ACH-806 in replicons. Genotype 1a, 1b, and 2a recombinants showed viral spread under long-term treatment with ACH-806, without acquisition of resistance mutations in the NS3-NS4A region. Relatively high concentrations of ACH-806 inhibited viral assembly, but not replication, in a single-cycle production assay. The developed HCV culture systems will facilitate studies benefitting from expression of genotype-specific NS4A in a constant backbone in the context of the complete viral replication cycle, including functional studies and evaluations of the efficacy of antivirals. PMID:24060868

  20. The Norovirus NS3 Protein Is a Dynamic Lipid- and Microtubule-Associated Protein Involved in Viral RNA Replication.

    Science.gov (United States)

    Cotton, Ben T; Hyde, Jennifer L; Sarvestani, Soroush T; Sosnovtsev, Stanislav V; Green, Kim Y; White, Peter A; Mackenzie, Jason M

    2017-02-01

    Norovirus (NoV) infections are a significant health burden to society, yet the lack of reliable tissue culture systems has hampered the development of appropriate antiviral therapies. Here we show that the NoV NS3 protein, derived from murine NoV (MNV), is intimately associated with the MNV replication complex and the viral replication intermediate double-stranded RNA (dsRNA). We observed that when expressed individually, MNV NS3 and NS3 encoded by human Norwalk virus (NV) induced the formation of distinct vesicle-like structures that did not colocalize with any particular protein markers to cellular organelles but localized to cellular membranes, in particular those with a high cholesterol content. Both proteins also showed some degree of colocalization with the cytoskeleton marker β-tubulin. Although the distribution of MNV and NV NS3s were similar, NV NS3 displayed a higher level of colocalization with the Golgi apparatus and the endoplasmic reticulum (ER). However, we observed that although both proteins colocalized in membranes counterstained with filipin, an indicator of cholesterol content, MNV NS3 displayed a greater association with flotillin and stomatin, proteins known to associate with sphingolipid- and cholesterol-rich microdomains. Utilizing time-lapse epifluorescence microscopy, we observed that the membrane-derived vesicular structures induced by MNV NS3 were highly motile and dynamic in nature, and their movement was dependent on intact microtubules. These results begin to interrogate the functions of NoV proteins during virus replication and highlight the conserved properties of the NoV NS3 proteins among the seven Norovirus genogroups. Many mechanisms involved in the replication of norovirus still remain unclear, including the role for the NS3 protein, one of seven nonstructural viral proteins, which remains to be elucidated. This study reveals that murine norovirus (MNV) NS3 is intimately associated with the viral replication complex and ds

  1. Adapted J6/JFH1-based hepatitis C virus recombinants with genotype-specific NS4A show similar efficacies against lead protease inhibitors, alpha interferon and a putative NS4A inhibitor

    DEFF Research Database (Denmark)

    Gottwein, Judith M; Jensen, Sanne B; Serre, Stéphanie B N

    2013-01-01

    To facilitate studies of hepatitis C virus (HCV) NS4A, we aimed at developing J6/JFH1-based recombinants with genotype 1- to 7-specific NS4A proteins. We developed efficient culture systems expressing NS4A proteins of genotypes (isolates) 1a (H77 and TN), 1b (J4), 2a (J6), 4a (ED43), 5a (SA13), 6a......), boceprevir (Sch503034), simeprevir (TMC435350), danoprevir (ITMN-191), and vaniprevir (MK-7009), to alpha interferon 2b, and to the putative NS4A inhibitor ACH-806. The efficacy of ACH-806 was lower than that of protease inhibitors and was not influenced by changes at amino acids 1042 and 1065 (in the NS3...

  2. Host competence and helicase activity differences exhibited by West Nile viral variants expressing NS3-249 amino acid polymorphisms.

    Directory of Open Access Journals (Sweden)

    Stanley A Langevin

    Full Text Available A single helicase amino acid substitution, NS3-T249P, has been shown to increase viremia magnitude/mortality in American crows (AMCRs following West Nile virus (WNV infection. Lineage/intra-lineage geographic variants exhibit consistent amino acid polymorphisms at this locus; however, the majority of WNV isolates associated with recent outbreaks reported worldwide have a proline at the NS3-249 residue. In order to evaluate the impact of NS3-249 variants on avian and mammalian virulence, multiple amino acid substitutions were engineered into a WNV infectious cDNA (NY99; NS3-249P and the resulting viruses inoculated into AMCRs, house sparrows (HOSPs and mice. Differential viremia profiles were observed between mutant viruses in the two bird species; however, the NS3-249P virus produced the highest mean peak viral loads in both avian models. In contrast, this avian modulating virulence determinant had no effect on LD50 or the neurovirulence phenotype in the murine model. Recombinant helicase proteins demonstrated variable helicase and ATPase activities; however, differences did not correlate with avian or murine viremia phenotypes. These in vitro and in vivo data indicate that avian-specific phenotypes are modulated by critical viral-host protein interactions involving the NS3-249 residue that directly influence transmission efficiency and therefore the magnitude of WNV epizootics in nature.

  3. Viperin restricts Zika virus and tick-borne encephalitis virus replication by targeting NS3 for proteasomal degradation.

    Science.gov (United States)

    Panayiotou, Christakis; Lindqvist, Richard; Kurhade, Chaitanya; Vonderstein, Kirstin; Pasto, Jenny; Edlund, Karin; Upadhyay, Arunkumar S; Överby, Anna K

    2018-01-10

    Flaviviruses are arthropod-borne viruses that constitute a major global health problem, with millions of human infections annually. Their pathogenesis ranges from mild illness to severe manifestations such as hemorrhagic fever and fatal encephalitis. Type I interferons (IFNs) are induced in response to viral infection, and stimulate the expression of interferon-stimulated genes (ISGs), including that encoding viperin (virus-inhibitory protein, endoplasmic reticulum-associated, IFN-inducible), which shows antiviral activity against a broad spectrum of viruses including several flaviviruses. Here we describe a novel antiviral mechanism exerted by viperin against two prominent flaviviruses, tick-borne encephalitis virus (TBEV) and Zika virus (ZIKV). Viperin was found to interact and co-localize with the structural proteins pre-membrane (prM) and envelope (E) of TBEV, as well as the non-structural (NS) proteins NS2A, NS2B, and NS3. Interestingly, viperin expression reduced the NS3 protein level, and the stability of the other interacting viral proteins, but only in the presence of NS3. We also found that although viperin interacted with NS3 of mosquito-borne flaviviruses (ZIKV, Japanese encephalitis virus, and yellow fever virus), only ZIKV was sensitive to the antiviral effect of viperin. This sensitivity correlated with viperin's ability to induce proteasome-dependent degradation of NS3. ZIKV and TBEV replication was rescued completely when NS3 was overexpressed, suggesting that the viral NS3 is the specific target of viperin. In summary, we present here a novel antiviral mechanism of viperin that is selective for specific viruses in the genus Flavivirus, affording the possibility of new drug targets that can be used for therapeutic intervention.ImportanceFlaviviruses are a group of enveloped RNA viruses that cause severe diseases in humans and animals worldwide, but no antiviral treatment is yet available. Viperin, a host protein produced in response to infection

  4. Ledipasvir/sofosbuvir-based treatment of patients with chronic genotype-1 HCV infection and cirrhosis: results from two Phase II studies.

    Science.gov (United States)

    Lawitz, Eric; Poordad, Fred; Hyland, Robert H; Wang, Jing; Liu, Lin; Dvory-Sobol, Hadas; Brainard, Diana M; McHutchison, John G; Gutierrez, Julio A

    2016-01-01

    Ledipasvir/sofosbuvir ± ribavirin administered for 12 weeks to patients with genotype-1 HCV infection and compensated cirrhosis is effective and well-tolerated. The Phase II TRILOGY-1 and TRILOGY-2 studies investigated whether ledipasvir/sofosbuvir plus the non-nucleotide NS5B inhibitor GS-9669 or the NS3/4A protease inhibitor vedroprevir could reduce treatment duration and/or eliminate the need for ribavirin in genotype-1 HCV-infected patients with compensated cirrhosis. In TRILOGY-1, 100 cirrhotic patients were randomized (1:1:1) to 8 weeks of ledipasvir/sofosbuvir plus ribavirin, ledipasvir/sofosbuvir plus GS-9669 250 mg or ledipasvir/sofosbuvir plus GS-9669 500 mg. In TRILOGY-2, 46 previously treated cirrhotic patients were randomized (1:1) to 8 weeks of ledipasvir/sofosbuvir plus vedroprevir ± ribavirin. The primary end points were the proportion of patients with sustained virological response 12 weeks after treatment discontinuation (SVR12) and safety. In both studies, most patients were male (each 65%) and white (92-96%), infected with HCV genotype-1a (62-70%) and had IL28B non-CC genotypes (82-87%). In total, 37-39% of patients were Hispanic or Latino. SVR12 rates were similar across treatment arms in TRILOGY-1 (82-91%) and TRILOGY-2 (88-95%); no patient had on-treatment virological failure. Two serious adverse events (acute myocardial infarction and cardiomyopathy) were reported in two patients participating in TRILOGY-1, both of whom had pre-existing cardiac conditions. Laboratory abnormalities were infrequent. All ledipasvir/sofosbuvir-based regimens were well-tolerated. To shorten therapy and eliminate ribavirin, use of a more potent third agent or a third agent with a different mechanism of action may be required.

  5. Capsid, membrane and NS3 are the major viral proteins involved in autophagy induced by Japanese encephalitis virus.

    Science.gov (United States)

    Wang, Xiujin; Hou, Lei; Du, Jige; Zhou, Lei; Ge, Xinna; Guo, Xin; Yang, Hanchun

    2015-08-05

    Japanese encephalitis virus (JEV) is an important zoonotic pathogen causing viral encephalitis in human and reproductive failure in pigs. In the present study, we first examined the autophagy induced by JEV infection in host cells, and then analyzed the JEV proteins involving in autophagy induction, and further investigated the relationship between viral protein and immunity-related GTPases M (IRGM). Our results showed that JEV infection could induce autophagy in host cells and autophagy promoted the replication of JEV in vitro; the cells transfected with individual plasmid that was expressing C, M and NS3 had a significantly higher conversion of LC3-I/II, and enhanced LC3 signals with the fluorescence punctuates accumulation which was completely co-localized with LC3 and increased number of autophagosomes-like vesicles, suggesting that C, M and NS3 are the major viral proteins involving in autophagy induction upon JEV infection; the virus titer in the cells treated by the siRNA specific for IRGM had a significant decrease, and the NS3 signals in the cells transfected with the plasmid that was expressing NS3 were completely co-localized with the IRGM signals, suggesting that the NS3 of JEV could target IRGM which may play a role in the replication of JEV. Our findings help to understand the role of autophagy in JEV and other flaviviruses infections. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Research of G3-PLC net self-organization processes in the NS-3 modeling framework

    Science.gov (United States)

    Pospelova, Irina; Chebotayev, Pavel; Klimenko, Aleksey; Myakochin, Yuri; Polyakov, Igor; Shelupanov, Alexander; Zykov, Dmitriy

    2017-11-01

    When modern infocommunication networks are designed, the combination of several data transfer channels is widely used. It is necessary for the purposes of improvement in quality and robustness of communication. Communication systems based on more than one data transfer channel are named heterogeneous communication systems. For the design of a heterogeneous network, the most optimal solution is the use of mesh technology. Mesh technology ensures message delivery to the destination under conditions of unpredictable interference environment situation in each of two channels. Therewith, one of the high-priority problems is the choice of a routing protocol when the mesh networks are designed. An important design stage for any computer network is modeling. Modeling allows us to design a few different variants of design solutions and also to compute all necessary functional specifications for each of these solutions. As a result, it allows us to reduce costs for the physical realization of a network. In this article the research of dynamic routing in the NS3 simulation modeling framework is presented. The article contains an evaluation of simulation modeling applicability in solving the problem of heterogeneous networks design. Results of modeling may be afterwards used for physical realization of this kind of networks.

  7. Implementation of quantum key distribution network simulation module in the network simulator NS-3

    Science.gov (United States)

    Mehic, Miralem; Maurhart, Oliver; Rass, Stefan; Voznak, Miroslav

    2017-10-01

    As the research in quantum key distribution (QKD) technology grows larger and becomes more complex, the need for highly accurate and scalable simulation technologies becomes important to assess the practical feasibility and foresee difficulties in the practical implementation of theoretical achievements. Due to the specificity of the QKD link which requires optical and Internet connection between the network nodes, to deploy a complete testbed containing multiple network hosts and links to validate and verify a certain network algorithm or protocol would be very costly. Network simulators in these circumstances save vast amounts of money and time in accomplishing such a task. The simulation environment offers the creation of complex network topologies, a high degree of control and repeatable experiments, which in turn allows researchers to conduct experiments and confirm their results. In this paper, we described the design of the QKD network simulation module which was developed in the network simulator of version 3 (NS-3). The module supports simulation of the QKD network in an overlay mode or in a single TCP/IP mode. Therefore, it can be used to simulate other network technologies regardless of QKD.

  8. (HCV) among alcoholics

    African Journals Online (AJOL)

    GREGORY

    2010-12-21

    Dec 21, 2010 ... alcoholics who do not have liver disease (Coelho–Little et al., 1995; Mendenhall et al., 1991; Takase et al., 1993). HCV is transmitted primarily through contaminated blood and less effectively through human bodily secre- tions. HCV has been detected in saliva, urine, semen and ascetic fluid (Campbell et ...

  9. Daclatasvir plus Asunaprevir Treatment for Real-World HCV Genotype 1-Infected Patients in Japan.

    Science.gov (United States)

    Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Suzuki, Eiichiro; Arai, Makoto; Haga, Yuki; Sasaki, Reina; Wu, Shuang; Nakamoto, Shingo; Imazeki, Fumio; Yokosuka, Osamu

    2016-01-01

    Background. All-oral combination of direct-acting antivirals could lead to higher sustained virologic response (SVR) in hepatitis C virus (HCV)-infected patients. In the present study, we examined the efficacy and safety of the dual oral treatment with HCV nonstructural protein (NS) 5A inhibitor daclatasvir (DCV) plus HCV NS3/4A inhibitor asunaprevir (ASV) for 24 weeks in real-world HCV genotype 1-infected Japanese individuals. Methods. After screening for HCV NS5A resistance-associated variants (RAVs) by PCR invader assay, a total of 54 Japanese patients infected with HCV genotype 1 treated with DCV plus ASV were retrospectively analyzed. SVR12 was used for evaluation of the virologic response. Results. Of the total 54 patients, 46 patients (85.2%) were treated with DCV plus ASV for 24 weeks and achieved SVR12. The other 8 patients (14.8%) discontinued this treatment before 24 weeks due to adverse events. Of these 8 patients, 5 and 3 patients did and did not achieve SVR12, respectively. Finally, 51 of 54 (94.4%) patients achieved SVR12. Conclusion. Treatment with DCV and ASV after screening for HCV NS5A RAVs by PCR invader assay is effective and safe in the treatment of real-world HCV genotype 1-infected patients in Japan.

  10. Comparison of HCV core antigen and anti-HCV with HCV RNA results

    African Journals Online (AJOL)

    Background: The measurement of anti-HCV antibodies using immunological methods and the confirmation of viral nuclear acid based on molecular methods is important in diagnosis and follow-up of the HCV infection. Objectives: In this study, we aimed to analyse HCV core Antigen positivity among anti-HCV antibody ...

  11. Development of a competitive ELISA for NS3 antibodies as DIVA test accompanying the novel Disabled Infectious Single Animal (DISA) vaccine for Bluetongue.

    Science.gov (United States)

    Tacken, Mirriam G J; Daus, Franz J; Feenstra, Femke; van Gennip, René G P; van Rijn, Piet A

    2015-10-13

    Recently, we have developed a novel vaccine for Bluetongue named BT Disabled Infectious Single Animal (DISA) vaccine. Due to the lack of non-essential NS3/NS3a protein, BT DISA vaccine is a replicating vaccine, but without the inherent risks of live-attenuated vaccines, such as residual virulence or reversion to virulence by mutations, reassortment with field virus, horizontal spread by vectors and vertical transmission. The immune response induced by BT DISA vaccines is rapidly induced, highly protective and serotype specific which is dependent on the immunodominant and serotype determining VP2 protein. The BT DISA vaccine platform provides the replacement of exclusively VP2 from different serotypes in order to safely formulate multivalent cocktail vaccines. The lack of NS3/NS3a directed antibodies by BT DISA vaccination enables differentiation of infected from vaccinated animals (DIVA principle). A highly conserved immunogenic site corresponding to the late domain was mapped in the N-terminal region of NS3. We here established an NS3-specific competitive ELISA (NS3 cELISA) as serological DIVA test accompanying BT DISA vaccines. To this end, NS3 protein missing putative transmembrane regions was produced in large amounts in bacteria and used as antigen in the NS3 cELISA which was investigated with a variety of sera. The NS3 cELISA displayed a high sensitivity and specificity similar to the commercially available VP7-specific cELISA. Results of previously performed vaccination-challenge trials with BT DISA vaccines clearly demonstrate the DIVA system based on the NS3 cELISA and BT vaccine free of NS3 protein. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. All-oral combination of ledipasvir, vedroprevir, tegobuvir, and ribavirin in treatment-naïve patients with genotype 1 HCV infection.

    Science.gov (United States)

    Wyles, David L; Rodriguez-Torres, Maribel; Lawitz, Eric; Shiffman, Mitchell L; Pol, Stanislas; Herring, Robert W; Massetto, Benedetta; Kanwar, Bittoo; Trenkle, James D; Pang, Phil S; Zhu, Yanni; Mo, Hongmei; Brainard, Diana M; Subramanian, G Mani; McHutchison, John G; Habersetzer, François; Sulkowski, Mark S

    2014-07-01

    This phase II trial assessed the efficacy and safety of a combination regimen of the nonstructural protein (NS)5A inhibitor ledipasvir (LDV), NS3 protease inhibitor vedroprevir (VDV), non-nucleoside NS5B inhibitor tegobuvir (TGV), and ribavirin (RBV) in treatment-naïve patients with chronic hepatitis C virus (HCV) genotype 1 without cirrhosis. Patients were randomized 1:2 to LDV 30 mg once daily (QD; Arm 1; n = 46) or LDV 90 mg QD (Arm 2; n = 94); patients in both arms also received VDV 200 mg QD, TGV 30 mg twice-daily, and RBV 1,000-1,200 mg/day. Patients in Arm 2 with vRVR, defined as HCV RNA below the lower limit of quantification (LLOQ) from treatment weeks 2 to 10, were randomized 1:1 to stop treatment at 12 weeks or continue for 24 weeks. Sustained virologic response 12 weeks after treatment (SVR12) was higher in patients receiving 90 mg of LDV for 24 weeks (63%), compared with LDV 90 mg for 12 weeks (54%) and LDV 30 mg for 24 weeks (48%). In patients with very rapid virologic response (vRVR) in Arm 2, SVR12 was achieved by 68% and 81% of patients treated for 12 and 24 weeks, respectively. Virologic breakthrough was more common in patients with HCV genotype 1a and was associated with resistance-associated variants for all three direct-acting antiviral agents (DAAs); however, in all but 1 patient who relapsed, resistance-associated variants directed against only one or two of the DAAs were detected. The most common adverse events were fatigue, headache, nausea, rash, and diarrhea. In patients with HCV genotype 1, an interferon-free regimen containing LDV/VDV/TGV/RBV was well tolerated and led to SVR12 in up to 63% of patients. LDV 90 mg is currently being investigated in combination with the nucleotide polymerase inhibitor, sofosbuvir. © 2014 by the American Association for the Study of Liver Diseases.

  13. Development of a competitive ELISA for NS3 antibodies as DIVA test accompanying the novel Disabled Infectious Single Animal (DISA) vaccine for bluetongue

    NARCIS (Netherlands)

    Tacken, M.G.J.; Daus, F.J.; Feenstra, F.; Gennip, van H.G.P.; Rijn, van P.A.

    2015-01-01

    Recently, we have developed a novel vaccine for Bluetongue named BT Disabled Infectious Single Animal (DISA) vaccine. Due to the lack of non-essential NS3/NS3a protein, BT DISA vaccine is a replicating vaccine, but without the inherent risks of live-attenuated vaccines, such as residual virulence or

  14. Protease inhibitor

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to a polypeptide exhibiting a protease inhibitory activity and uses of said polypeptide in methods for inhibiting, directly or indirectly, one or more proteases of the blood clotting cascade. The invention also relates to use of said polypeptide as a pharmaceutical e...

  15. Processing Proteases

    DEFF Research Database (Denmark)

    Ødum, Anders Sebastian Rosenkrans

    Processing proteases are proteases which proteolytically activate proteins and peptides into their biologically active form. Processing proteases play an important role in biotechnology as tools in protein fusion technology. Fusion strategies where helper proteins or peptide tags are fused...... to the protein of interest are an elaborate method to optimize expression or purification systems. It is however critical that fusion proteins can be removed and processing proteases can facilitate this in a highly specific manner. The commonly used proteases all have substrate specificities to the N......-terminal of the scissile bond, leaving C-terminal fusions to have non-native C-termini after processing. A solution yielding native C-termini would allow novel expression and purification systems for therapeutic proteins and peptides.The peptidyl-Lys metallopeptidase (LysN) of the fungus Armillaria mellea (Am) is one...

  16. Interaction between the yellow fever virus nonstructural protein NS3 and the host protein Alix contributes to the release of infectious particles.

    Science.gov (United States)

    Carpp, Lindsay N; Galler, Ricardo; Bonaldo, Myrna C

    2011-01-01

    The ESCRT (endosomal sorting complex required for transport) machinery normally executes cargo sorting and internalization during multivesicular body biogenesis, but is also utilized by several enveloped viruses to facilitate their budding from cellular membranes. Although the mechanisms of flavivirus infectious particle assembly and release are poorly understood, the nonstructural protein NS3 has been reported to have an essential role via an undescribed mechanism. Here, we shed light on the role of NS3 by connecting it to the host factor Alix, a protein intimately connected with the ESCRT machinery. We demonstrate that NS3 and Alix interact and show that dominant negative versions of Alix inhibit YFV release. Furthermore, we show that NS3 supplied in trans rescues this effect. We propose that the interaction between NS3 and Alix contributes to YFV release. Copyright © 2010 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  17. Lack of a clinically significant drug-drug interaction in healthy volunteers between the hepatitis C virus protease inhibitor boceprevir and the HIV integrase inhibitor raltegravir

    NARCIS (Netherlands)

    Kanter, C.T. de; Blonk, M.I.; Colbers, A.P.; Schouwenberg, B.J.J.W.; Burger, D.M.

    2013-01-01

    BACKGROUND: Patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) are likely to use both HIV and HCV treatment. Drug-drug interactions have been demonstrated between boceprevir, an HCV protease inhibitor, and frequently prescribed antiretroviral drugs, such as

  18. HCV and Oxidative Stress: Implications for HCV Life Cycle and HCV-Associated Pathogenesis

    Directory of Open Access Journals (Sweden)

    Regina Medvedev

    2016-01-01

    Full Text Available HCV (hepatitis C virus is a member of the Flaviviridae family that contains a single-stranded positive-sense RNA genome of approximately 9600 bases. HCV is a major causative agent for chronic liver diseases such as steatosis, fibrosis, cirrhosis, and hepatocellular carcinoma which are caused by multifactorial processes. Elevated levels of reactive oxygen species (ROS are considered as a major factor contributing to HCV-associated pathogenesis. This review summarizes the mechanisms involved in formation of ROS in HCV replicating cells and describes the interference of HCV with ROS detoxifying systems. The relevance of ROS for HCV-associated pathogenesis is reviewed with a focus on the interference of elevated ROS levels with processes controlling liver regeneration. The overview about the impact of ROS for the viral life cycle is focused on the relevance of autophagy for the HCV life cycle and the crosstalk between HCV, elevated ROS levels, and the induction of autophagy.

  19. HCV and Rheumatic Disease

    Science.gov (United States)

    ... of treating liver disease and your doctors who treat the non-liver symptoms of HCV. Also, make sure you get long-term follow-up care. This is vital, since the liver disease can become worse, leading to liver failure or liver cancer. Support groups also provide helpful support and coping ...

  20. HCV Virus and Lymphoid Neoplasms

    Directory of Open Access Journals (Sweden)

    Yutaka Tsutsumi

    2011-01-01

    Full Text Available Hepatitis C virus (HCV is one of the viruses known to cause hepatic cancer. HCV is also believed to be involved in malignant lymphoma. In this paper, we investigated characteristics of malignant lymphoma cases that were anti-HCV antibody (HCV-Ab positive. We were able to perform pathological examinations on 13 out of 14 HCV-positive cases. Of these, lymphoid tissues of 10 stained positive for HCV-Ab. There was no significant correlation between the degree of HCV staining and the rate of recurrence or resistance to treatment. However, there did appear to be a consistent decrease in the amount of HCV-RNA between pre- and posttreatment among HCV-Ab-positive cases; that is, treatment-resistant cases that exhibited resistance from the first treatment and recurrent cases more frequently had a higher HCV level at treatment termination compared to the pretreatment level. This suggests that the HCV virus either accelerates oncogenesis by direct interaction with B cells or indirectly affects lymphoma prognosis.

  1. Supermarket Proteases.

    Science.gov (United States)

    Hagar, William G.; Bullerwell, Lornie D.

    2003-01-01

    Presents a laboratory activity on enzymes. Uses common items found in the supermarket that contain protease enzymes, such as contact lens cleaner and meat tenderizer. Demonstrates the digestion of gelatin proteins as part of enzymatic reactions. (Author/SOE)

  2. HCV triple therapy in co-infection HIV/HCV is not associated with a different risk of developing major depressive disorder

    Directory of Open Access Journals (Sweden)

    Renata Fialho

    2014-11-01

    Full Text Available Introduction: Hepatitis C (HCV treatment options have changed with the development of direct activity antivirals (DAAs and the availability of triple therapies have improved HCV cure rates. A common neuropsychiatric side effect of pegylated-interferon and ribavirin treatment is major depressive disorder (MDD, however little is known about such adverse events with protease inhibitor-based triple therapy. The aim of this study was to assess the rate of MDD in co-infected HIV HCV patients undergoing different HCV treatments. Methods: All participants were co-infected HIV HCV attending the Royal Sussex County Hospital Brighton hepatology outpatient clinic between 2010 and 2014. Participants were assessed for DSM-IV MDD and depression severity (using the Hamilton depression scale (HAMD at baseline and monthly after treatment initiation. HIV and HCV stages, genotype, reinfection and standard demographic variables were recorded. Influence of HCV stage (acute vs. chronic and type of treatment (classic vs triple, emergence of MDD and clearance outcomes were analyzed using repeated measures and logistic regression models. Results: Fifty participants with a mean age of 42.65 years (SD=10.32 were included; most were male (98%. The majority had contracted HCV genotype 1 (64% or 4 (26%. The HCV stage and treatment groups were matched for age and depression at baseline. No significant differences were found on virological outcomes considering HCV stage and treatment. From baseline to SVR, there was a significant increase in HAMD scores, F(4,36=10.09, p<.001; this was not significantly influenced by HCV stage, F(4,35=0.54, p=.708 or HCV treatment group, F(4,35=0.60, p=.664. Those with chronic HCV were more likely to transition to MDD than acute infection (OR 7.77, 95% CI 2.04–29.54, p=.003. No differences were found for depression emergence by HCV treatment group (OR 0.83, 95% CI 0.22–3.13, p=.787. Conclusions: HCV triple therapy was not associated with a

  3. Induction of broadly neutralising HCV antibodies in mice by integration-deficient lentiviral vector-based pseudotyped particles.

    Directory of Open Access Journals (Sweden)

    Yao Deng

    Full Text Available INTRODUCTION: Integration-deficient lentiviral vectors (IDLVs are a promising platform for immunisation to elicit both humoral immunity and cellular mediated immunity (CMI. Here, we compared the specific immunity in mice immunised via different regimens (homologous and cocktail with IDLV-based HCV pseudoparticles (HCVpps carrying pseudotyped glycoproteins E1E2 and bearing the HCV NS3 gene. Humoral and cell-mediated immune responses were also evaluated after IDLV-HCVpp immunisation combined with heterologous rAd5-CE1E2 priming protocols. Sera from the mice effectively elicited anti-E1, -E2, and -NS3 antibody responses, and neutralised various HCVpp subtypes (1a, 1b, 2a, 3a and 5a. No significant CMI was detected in the groups immunised with IDLV-based HCVpps. In contrast, the combination of rAd5-CE1E2 priming and IDLV-based HCVpp boosting induced significant CMI against multiple antigens (E1, E2, and NS3. CONCLUSION: IDLV-based HCVpps are a promising vaccination platform and the combination of rAd5-CE1E2 and IDLV-based HCVpp prime-boost strategy should be further explored for the development of a cross-protective HCV vaccine.

  4. Strong vaccine-induced CD8 T-cell responses have cytolytic function in a chimpanzee clearing HCV infection.

    Directory of Open Access Journals (Sweden)

    Babs E Verstrepen

    Full Text Available A single correlate of effective vaccine protection against chronic HCV infection has yet to be defined. In this study, we analyzed T-cell responses in four chimpanzees, immunized with core-E1-E2-NS3 and subsequently infected with HCV1b. Viral clearance was observed in one animal, while the other three became chronically infected. In the animal that cleared infection, NS3-specific CD8 T-cell responses were observed to be more potent in terms of frequency and polyfunctionality of cytokine producing cells. Unique to this animal was the presence of killing-competent CD8 T-cells, specific for NS3 1258-1272, being presented by the chimpanzee MHC class I molecule Patr-A*03∶01, and a high affinity recognition of this epitope. In the animals that became chronically infected, T-cells were able to produce cytokines against the same peptide but no cytolysis could be detected. In conclusion, in the animal that was able to clear HCV infection not only cytokine production was observed but also cytolytic potential against specific MHC class I/peptide-combinations.

  5. Effects of HCV proteins in current HCV transgenic models.

    Science.gov (United States)

    Jiao, Jian; Wang, Jiangbin; Sallberg, Matii

    2010-02-01

    Hepatits C virus (HCV) is an enveloped virus with positive-sense single-stranded RNA genome that causes both acute and persistent infections associated with chronic hepatitis, cirrhosis and hepatocellular carcinoma, which needs fully functional human hepatocytes for its development. Due to the strict human tropism of HCV, only human and higher primates such as chimpanzees have been receptive to HCV infection and development, cognition about pathophysiololgy and host immune responses of HCV infection is limited by lacking of simple laboratory models of infection for a long time. During the past decade, gene transfer approaches have been helpful to the understanding of the molecular basis of human disease. Transgenic cell lines, chimeric and transgenic animal models were developed and had been demonstrated their invaluable benefits. This review focuses on the existing HCV transgenic models and summarize the relative results about probable pathophysical changes induced by HCV proteins.

  6. Steady-state NTPase activity of Dengue virus NS3: number of catalytic sites, nucleotide specificity and activation by ssRNA.

    Directory of Open Access Journals (Sweden)

    J Jeremías Incicco

    Full Text Available Dengue virus nonstructural protein 3 (NS3 unwinds double stranded RNA driven by the free energy derived from the hydrolysis of nucleoside triphosphates. This paper presents the first systematic and quantitative characterization of the steady-state NTPase activity of DENV NS3 and their interaction with ssRNA. Substrate curves for ATP, GTP, CTP and UTP were obtained, and the specificity order for these nucleotides - evaluated as the ratio (kcat /KM - was GTP[Formula: see text]ATP[Formula: see text]CTP [Formula: see text] UTP, which showed that NS3 have poor ability to discriminate between different NTPs. Competition experiments between the four substrates indicated that all of them are hydrolyzed in one and the same catalytic site of the enzyme. The effect of ssRNA on the ATPase activity of NS3 was studied using poly(A and poly(C. Both RNA molecules produced a 10 fold increase in the turnover rate constant (kcat and a 100 fold decrease in the apparent affinity (KM for ATP. When the ratio [RNA bases]/[NS3] was between 0 and [Formula: see text]20 the ATPase activity was inhibited by increasing both poly(A and poly(C. Using the theory of binding of large ligands (NS3 to a one-dimensional homogeneous lattice of infinite length (RNA we tested the hypothesis that inhibition is the result of crowding of NS3 molecules along the RNA lattices. Finally, we discuss why this hypothesis is consistent with the idea that the ATPase catalytic cycle is tightly coupled to the movement of NS3 helicase along the RNA.

  7. ITPA Genotypes Predict Anemia but Do Not Affect Virological Response with Interferon-Free Faldaprevir, Deleobuvir, and Ribavirin for HCV Infection.

    Directory of Open Access Journals (Sweden)

    Tarik Asselah

    Full Text Available Whether inosine triphosphatase (ITPA gene polymorphisms predict anemia during interferon-free therapy in chronic hepatitis C virus (HCV-infected patients is unknown. We examined the relationship between two ITPA polymorphisms, anemia, and sustained virological response 12 weeks post-treatment (SVR12 in patients receiving the NS3/4A protease inhibitor faldaprevir, the non-nucleoside polymerase inhibitor deleobuvir, and ribavirin.HCV genotype 1-infected, treatment-naïve patients (N = 362 were randomized and treated in one of five treatment arms with faldaprevir and deleobuvir with or without ribavirin. Two ITPA polymorphisms (rs1127354 and rs6051702 were genotyped and defined as ITPA-deficient (rs1127354 AA or AC; rs6051702 CC or CA or ITPA-non-deficient (rs1127354 CC; rs6051702 AA according to their association with ITPA deficiency. Baseline and on-treatment variables associated with anemia and SVR12 were identified using logistic regression.In the pooled ribavirin-containing arms, 10.1% (32/316 of patients experienced on-treatment hemoglobin <10 g/dL, and 32.6% (103/316 experienced on-treatment hemoglobin <10 g/dL or a change from baseline ≥3.5 g/dL. Of the latter group, 99% (102/103 had the ITPA-non-deficient rs1127354 genotype. Other variables associated with on-treatment hemoglobin <10 g/dL or a decrease ≥3.5 g/dL were age, baseline hemoglobin, rs6051702 genotype, and plasma ribavirin concentration. In a multivariate analysis, high plasma ribavirin concentration, low baseline hemoglobin, HCV genotype 1b, and IL28B genotype CC were associated with higher SVR12.The ITPA rs1127354 CC and rs6051702 AA genotypes may predict ribavirin-induced anemia during treatment with interferon-free, ribavirin-containing regimens. With this interferon-free regimen, SVR was associated with ribavirin levels, but not with anemia or ITPA genotypes.ClinicalTrials.gov: NCT01132313.

  8. Characterisation of interaction between NS3 and NS5B protein of classical swine fever virus by deletion of terminal sequences of NS5B.

    Science.gov (United States)

    Wang, Yujing; Zhu, Zailing; Wang, Ping; Yu, Jialin; Wan, Lingzhu; Chen, Jun; Xiao, Ming

    2011-03-01

    The NS3-NS5B interaction of classical swine fever virus (CSFV) is important for viral replication. For characterisation of the interaction between the NS3 and NS5B, a series of NS5B mutants with deletion of N-, C-terminal amino acids and quadruple alanine substitution mutations were produced. GST pull-down assays and immunoprecipitation analyses showed that NS5B and some NS5B mutants have NS3 binding activity. Further experimental data indicated that CSFV NS5B might contain two NS3 binding sites, one covering amino acids 63-99 located at the N-terminal end, another covering amino acids 611-642 at the C-terminal end. Assays for RNA-dependent RNA polymerase (RdRp) activity revealed that CSFV NS3 is able to enhance the RdRp activity of NS5B and some NS5B mutants in vitro. The enhancement might be obtained by NS3 binding to the two terminal sequences of NS5B, which could be attractive targets for drug development against CSFV. Copyright © 2011. Published by Elsevier B.V.

  9. Production and Optimization of Physicochemical Parameters of Cellulase Using Untreated Orange Waste by Newly Isolated Emericella variecolor NS3.

    Science.gov (United States)

    Srivastava, Neha; Srivastava, Manish; Manikanta, Ambepu; Singh, Pardeep; Ramteke, P W; Mishra, P K; Malhotra, Bansi D

    2017-10-01

    Cellulase enzymes have versatile industrial applications. This study was directed towards the isolation, production, and characterization of cellulase enzyme system. Among the five isolated fungal cultures, Emericella variecolor NS3 showed maximum cellulase production using untreated orange peel waste as substrate using solid-state fermentation (SSF). Maximum enzyme production of 31 IU/gds (per gram of dry substrate) was noticed at 6.0 g concentration of orange peel. Further, 50 °C was recorded as the optimum temperature for cellulase activity and the thermal stability for 240 min was observed at this temperature. In addition, the crude enzyme was stable at pH 5.0 and held its complete relative activity in presence of Mn 2+ and Fe 3+ . This study explored the production of crude enzyme system using biological waste with future potential for research and industrial applications.

  10. Hepatitis C virus (HCV) status in newborns born to HCV positive ...

    African Journals Online (AJOL)

    Group one: 30 women HCV antibody (Ab) positive/HCV RNA negative. Group two: 30 women HCV Ab positive/ HCV RNA positive. Newborn sera were subjected to HCV antibody testing, and detection of HCV viral RNA by PCR. Results: None of the newborns born to PCR negative females undergoing ICSI cycles showed ...

  11. A Review of Hepatitis C Virus (HCV) and the Current Management ...

    African Journals Online (AJOL)

    Background: Chronic Hepatitis C virus (HCV) is the primary cause of cirrhosis, hepatocellular carcinoma (HCC), and end- stage liver disease. The addition of protease inhibitor with peginterferon alfa and ribavirin (triple therapy) for genotype 1 infected patients, are the current standard of care. Method: Data was sourced ...

  12. Phylogenetics of HCV: Recent advances

    African Journals Online (AJOL)

    ONOS

    2010-09-06

    Sep 6, 2010 ... Tanaka (2006), studied the coalescent analysis indicated that a transition from constant size to rapid exponential growth (spread time) occurred in Japan in the 1920s. (HCV-1b), but not until the 1940s for the same genotype in Spain and other European countries. The spread time of HCV-1a in the United ...

  13. The NS3 and NS4A genes as the targets of RNA interference inhibit replication of Japanese encephalitis virus in vitro and in vivo.

    Science.gov (United States)

    Yuan, Lei; Wu, Rui; Liu, Hanyang; Wen, Xintian; Huang, Xiaobo; Wen, Yiping; Ma, Xiaoping; Yan, Qigui; Huang, Yong; Zhao, Qin; Cao, Sanjie

    2016-12-15

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that can cause acute encephalitis with a high fatality rate. RNA interference (RNAi) is a powerful tool to silence gene expression and a potential therapy for virus infection. In this study, the antiviral ability of eight shRNA expression plasmids targeting different sites of the NS3 and NS4A genes of JEV was determined in BHK21 cells and mice. The pGP-NS3-3 and pGP-NS4A-4 suppressed 93.9% and 82.0% of JEV mRNA in cells, respectively. The virus titer in cells was reduced approximately 950-fold by pretreating with pGP-NS3-4, and 640-fold by pretreating with pGP-NS4A-4. The results of western blot and immunofluorescence analysis showed JEV E protein and viral load in cells were remarkably inhibited by shRNA expression plasmids. The viral load in brains of mice pretreated with pGP-NS3-4 or pGP-NS4A-4 were reduced approximately 2400-fold and 800-fold, respectively, and the survival rate of mice challenged with JEV were 70% and 50%, respectively. However, the antiviral ability of shRNA expression plasmids was decreased over time. This study indicates that RNAi targeting of the NS3 and NS4A genes of JEV can sufficiently inhibit the replication of JEV in vitro and in vivo, and NS3 and NS4A genes might be potential targets of molecular therapy for JEV infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. HCV and HCC molecular epidemiology

    Directory of Open Access Journals (Sweden)

    Flor H. Pujol

    2007-02-01

    Full Text Available

    iHepatitis C virus (HCV is a member of the family Flaviviridae, responsible for the majority of the non-A non-B post-transfusion hepatitis before 1990. Around 170 millions persons in the world are thought to be infected with this virus. A high number of HCV-infected people develop cirrhosis and from these, a significant proportion progresses to hepatocellular carcinoma (HCC. Six HCV genotypes and a large number of subtypes in each genotype have been described. Infections with HCV genotype 1 are associated with the lowest therapeutic success. HCV genotypes 1, 2, and 3 have a worldwide distribution. HCV subtypes 1a and 1b are the most common genotypes in the United States and are also are predominant in Europe, while in Japan, subtype 1b is predominant. Although HCV subtypes 2a and 2b are relatively common in America, Europe, and Japan, subtype 2c is found commonly in northern Italy. HCV genotype 3a is frequent in intravenous drug abusers in Europe and the United States. HCV genotype 4 appears to be prevalent in Africa and the Middle East, and genotypes 5 and 6 seem to be confined to South Africa and Asia, respectively. HCC accounts for approximately 6% of all human cancers. Around 500,000 to 1 million cases occur annually worldwide, with HCC being the fifth common malignancy in men and the ninth in women. HCC is frequently a consequence of infection by HBV and HCV. The first line of evidences comes from epidemiologic studies. While HBV is the most frequent cause of HCC in many countries of Asia and South America, both HBV and HCV are found at similar frequencies, and eventually HCV at a higher frequency than HBV, among HCC patients in Europe, North America, and Japan. The cumulative appearance rate of HCC might be higher for HCV

  15. Preclinical evaluation of multi antigenic HCV DNA vaccine for the prevention of Hepatitis C virus infection.

    Science.gov (United States)

    Lee, Hyojin; Jeong, Moonsup; Oh, Jooyeon; Cho, Youngran; Shen, Xuefei; Stone, John; Yan, Jian; Rothkopf, Zachary; Khan, Amir S; Cho, Byung Mun; Park, Young K; Weiner, David B; Son, Woo-Chan; Maslow, Joel N

    2017-03-07

    Direct-acting antiviral treatment for hepatitis C virus (HCV) infection is costly and does not protect from re-infection. For human and chimpanzees, recovery from acute HCV infection correlates with host CD4+ and CD8+ T cell responses. DNA plasmids targeting the HCV non-structural antigens NS3, NS4, and NS5, were previously reported to induce robust and sustained T cell responses in mice and primates. These plasmids were combined with a plasmid encoding cytokine IL-28B, together named as VGX-6150. The dose-dependent T cell response and safety of VGX-6150 administered intramuscularly and followed by electroporation was assessed in mice. Immune responses plateaued at 20 μg/dose with IL-28B demonstrating significant immunoadjuvant activity. Mice administered VGX-6150 at 40, 400, and 800 μg given either as a single injection or as 14 injections given bi-weekly over 26 weeks showed no vaccine related changes in any clinical parameter compared to placebo recipients. There was no evidence of VGX-6150 accumulation at the injection site or in any organ 1 month following the 14th vaccination. Based on these studies, the approximate lethal dose (ALD) exceeds 800 μg/dose and the NOAEL was 800 μg/dose in mouse. In conclusion, VGX-6150 appears safe and a promising preventive vaccine candidate for HCV infection.

  16. Translation of the flavivirus kunjin NS3 gene in cis but not its RNA sequence or secondary structure is essential for efficient RNA packaging

    NARCIS (Netherlands)

    Pijlman, G.P.; Kondratieva, N.; Khromykh, A.A.

    2006-01-01

    Our previous studies using trans-complementation analysis of Kunjin virus (KUN) full-length cDNA clones harboring in-frame deletions in the NS3 gene demonstrated the inability of these defective complemented RNAs to be packaged into virus particles (W. J. Liu, P. L. Sedlak, N. Kondratieva, and A. A.

  17. Mutagenesis of the yellow fever virus NS2B protein: effects on proteolytic processing, NS2B-NS3 complex formation, and viral replication.

    Science.gov (United States)

    Chambers, T J; Nestorowicz, A; Amberg, S M; Rice, C M

    1993-11-01

    To study the role of specific regions of the yellow fever virus NS2B protein in proteolytic processing and association with the NS3 proteinase domain, a series of mutations were created in the hydrophobic regions and in a central conserved hydrophilic region proposed as a domain important for NS2B function. The effects of these mutations on cis cleavage at the 2B/3 cleavage site and on processing at other consensus cleavage sites for the NS3 proteinase in the nonstructural region were then characterized by cell-free translation and transient expression in BHK cells. Association between NS2B and the NS3 proteinase domain and the effects of mutations on complex formation were investigated by nondenaturing immunoprecipitation of these proteins expressed in infected cells, by cell-free translation, or by recombinant vaccinia viruses. Mutations within the hydrophobic regions had subtle effects on proteolytic processing, whereas mutations within the conserved domain dramatically reduced cleavage efficiency or abolished all cleavages. The conserved domain of NS2B is also implicated in formation of an NS2B-NS3 complex on the basis of the ability of mutations in this region to eliminate both association of these two proteins and trans-cleavage activity. In addition, mutations which either eliminated proteolytic processing or had no apparent effect on processing were found to abolish recovery of infectious virus following RNA transfection. These results suggest that the conserved region of NS2B is a domain essential for the function of the NS3 proteinase. Hydrophobic regions of NS2B whose structural integrity may not be essential for proteolytic processing may have additional functions during viral replication.

  18. Naturally Occurring Resistance-Associated Variants to Hepatitis C Virus Direct-Acting Antiviral Agents in Treatment-Naive HCV Genotype 6a-Infected Patients

    Directory of Open Access Journals (Sweden)

    Zhanyi Li

    2017-01-01

    Full Text Available Background and Objective. The direct-acting antiviral agents (DAAs antiviral therapy has drastically improved the prognosis of hepatitis C virus (HCV patients. However, the viral drug resistance-associated variants (RAVs can limit the efficacy of DAAs. For the HCV-6a is not the predominant prevalent genotype; the data on the prevalence of naturally occurring RAVs in it is scarce. Our study aims to assess the prevalence of RAVs in treatment-naive HCV-6a patients. Methods. Nested PCR assays were performed on 95 HCV-6a patients to amplify HCV viral regions of NS3, NS5A, and NS5B. Results. In NS3/4A region, we detected Q80K in 95.5% isolates (84/88 and D168E in 2.3% isolates (2/88. In NS5A region, we detected Q30R in 93.2% isolates (82/88, L31M in 4.6% isolates (4/88, and H58P in 6.8% isolates (6/88. In NS5B region, we detected A15G in 2.3% isolates (2/88, S96T in 1.1% isolates (1/88, and S282T in 20.7% isolates (17/88 and we detected I482L in 100% isolates (4/4, V494A in 50% isolates (2/4, and V499A in 100% isolates (4/4. Conclusions. RAVs to DAAs preexist in treatment-naive HCV-6a patients. Further studies should address the issue of the impact of RAVs in response to DAA therapies for HCV-6a patients.

  19. Intrinsic flexibility of West Nile virus protease in solution characterized using small-angle X-ray scattering.

    Science.gov (United States)

    Garces, Andrea P; Watowich, Stanley J

    2013-10-01

    West Nile virus (WNV) is a mosquito-borne flavivirus with a rapidly expanding global distribution. Infection can cause severe neurological disease and fatality in humans. Efforts are ongoing to develop antiviral drugs that inhibit the WNV protease, a viral enzyme required for polyprotein processing. Unfortunately, little is known about the solution structure of recombinant WNV protease (NS2B-NS3pro) used for antiviral drug discovery and development, although X-ray crystal structures and nuclear magnetic resonance (NMR) studies have provided valuable insights into the interactions between NS2B-NS3pro and peptide-based inhibitors. We completed small-angle X-ray scattering and Fourier transform infrared spectroscopy experiments to determine the solution structure and dynamics of WNV NS2B-NS3pro in the absence of a bound substrate or inhibitor. Importantly, these solution studies suggested that all or most of the NS2B cofactor was highly flexible and formed an ensemble of structures, in contrast to the NS2B tertiary structures observed in crystallographic and NMR studies. The secondary structure of NS2B-NS3pro in solution had high β-content, similar to the secondary structure observed in crystallographic studies. This work provided evidence of the intrinsic flexibility and conformational heterogeneity of the NS2B chain of the WNV protease in the absence of substratelike ligands, which should be considered during antiviral drug discovery and development efforts.

  20. Comparison of Elecsys Anti-HCV II Assay With Other HCV Screening Assays.

    Science.gov (United States)

    Li, Dongdong; Zhu, Siyuan; Wang, Tingting; An, Jingna; Wang, Lanlan; Tao, Chuanmin

    2016-09-01

    Early detection of hepatitis C virus (HCV) is an important step in preventing progression to cirrhosis and hepatocellular carcinoma. Serologic assays for anti-HCV antibody are valuable first-line tests in the screening and diagnosis of HCV infection. This study's aim was to evaluate the sensitivity and specificity of Elecsys Anti-HCV II assay for HCV screening. A total of 1,044 routine sera, 20 known HCV-positive samples, plus 54 preselected weakly positive samples were tested for anti-HCV with Elecsys Anti-HCV II assay, Elecsys Anti-HCV assays, InTec HCV enzymoimmunoassay (EIA), and Livzon Anti-HCV EIA. Interference test was assessed with additional 423 specimens without clinical evidence of HCV infection: preselected HCV weak reactive samples; dialysis samples; anti-HBc (antibody to HBV core antigen) (+), anti-Treponema pallidum (+), and anti-HIV (+) sera; and samples form autoimmune/alcoholic hepatitis or systemic Lupus erythematosus (SLE). Discrepant results were evaluated with recombinant immunoblot assay. The seroconversion panels were evaluated to assess how early each assay could detect HCV infection. The specificity (99.81%) of the Elecsys Anti-HCV II assay was less than that with the two EIA comparison methods. However, false-negative results were easily seen in the EIA assays. When serial bleeds of HCV panels were compared with the above-mentioned methods, the assay detected acute HCV infection only 3.5 days after a positive HCV-RNA nucleic acid test and earlier than the comparator assays. Sensitivities and specificities of the anti-HCV assays were sufficiently high for use in this study. The Elecsys Anti-HCV II assay is suitable for screening and reliable early detection of HCV infection. © 2015 Wiley Periodicals, Inc.

  1. Ledipasvir and sofosbuvir for previously treated HCV genotype 1 infection.

    Science.gov (United States)

    Afdhal, Nezam; Reddy, K Rajender; Nelson, David R; Lawitz, Eric; Gordon, Stuart C; Schiff, Eugene; Nahass, Ronald; Ghalib, Reem; Gitlin, Norman; Herring, Robert; Lalezari, Jacob; Younes, Ziad H; Pockros, Paul J; Di Bisceglie, Adrian M; Arora, Sanjeev; Subramanian, G Mani; Zhu, Yanni; Dvory-Sobol, Hadas; Yang, Jenny C; Pang, Phillip S; Symonds, William T; McHutchison, John G; Muir, Andrew J; Sulkowski, Mark; Kwo, Paul

    2014-04-17

    Effective treatment for hepatitis C virus (HCV) genotype 1 infection in patients who have not had a sustained virologic response to prior interferon-based therapy represents an unmet medical need. We conducted a phase 3, randomized, open-label study involving patients infected with HCV genotype 1 who had not had a sustained virologic response after treatment with peginterferon and ribavirin, with or without a protease inhibitor. Patients were randomly assigned to receive the NS5A inhibitor ledipasvir and the nucleotide polymerase inhibitor sofosbuvir in a once-daily, fixed-dose combination tablet for 12 weeks, ledipasvir-sofosbuvir plus ribavirin for 12 weeks, ledipasvir-sofosbuvir for 24 weeks, or ledipasvir-sofosbuvir plus ribavirin for 24 weeks. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. Among the 440 patients who underwent randomization and were treated, 20% had cirrhosis and 79% had HCV genotype 1a infection. The rates of sustained virologic response were high in all treatment groups: 94% (95% confidence interval [CI], 87 to 97) in the group that received 12 weeks of ledipasvir-sofosbuvir; 96% (95% CI, 91 to 99) in the group that received 12 weeks of ledipasvir-sofosbuvir and ribavirin; 99% (95% CI, 95 to 100) in the group that received 24 weeks of ledipasvir-sofosbuvir; and 99% (95% CI, 95 to 100) in the group that received 24 weeks of ledipasvir-sofosbuvir and ribavirin. No patient discontinued treatment owing to an adverse event. The most common adverse events were fatigue, headache, and nausea. Treatment with a once-daily, single-tablet regimen of ledipasvir and sofosbuvir resulted in high rates of sustained virologic response among patients with HCV genotype 1 infection who had not had a sustained virologic response to prior interferon-based treatment. (Funded by Gilead Sciences; ION-2 ClinicalTrials.gov number, NCT01768286.).

  2. Interferon Response in Hepatitis C Virus (HCV Infection: Lessons from Cell Culture Systems of HCV Infection

    Directory of Open Access Journals (Sweden)

    Pil Soo Sung

    2015-10-01

    Full Text Available Hepatitis C virus (HCV is a positive-stranded RNA virus that infects approximately 130–170 million people worldwide. In 2005, the first HCV infection system in cell culture was established using clone JFH-1, which was isolated from a Japanese patient with fulminant HCV infection. JFH-1 replicates efficiently in hepatoma cells and infectious virion particles are released into the culture supernatant. The development of cell culture-derived HCV (HCVcc systems has allowed us to understand how hosts respond to HCV infection and how HCV evades host responses. Although the mechanisms underlying the different outcomes of HCV infection are not fully understood, innate immune responses seem to have a critical impact on the outcome of HCV infection, as demonstrated by the prognostic value of IFN-λ gene polymorphisms among patients with chronic HCV infection. Herein, we review recent research on interferon response in HCV infection, particularly studies using HCVcc infection systems.

  3. Sofosbuvir, Velpatasvir, and Voxilaprevir for Previously Treated HCV Infection.

    Science.gov (United States)

    Bourlière, Marc; Gordon, Stuart C; Flamm, Steven L; Cooper, Curtis L; Ramji, Alnoor; Tong, Myron; Ravendhran, Natarajan; Vierling, John M; Tran, Tram T; Pianko, Stephen; Bansal, Meena B; de Lédinghen, Victor; Hyland, Robert H; Stamm, Luisa M; Dvory-Sobol, Hadas; Svarovskaia, Evguenia; Zhang, Jie; Huang, K C; Subramanian, G Mani; Brainard, Diana M; McHutchison, John G; Verna, Elizabeth C; Buggisch, Peter; Landis, Charles S; Younes, Ziad H; Curry, Michael P; Strasser, Simone I; Schiff, Eugene R; Reddy, K Rajender; Manns, Michael P; Kowdley, Kris V; Zeuzem, Stefan

    2017-06-01

    Patients who are chronically infected with hepatitis C virus (HCV) and who do not have a sustained virologic response after treatment with regimens containing direct-acting antiviral agents (DAAs) have limited retreatment options. We conducted two phase 3 trials involving patients who had been previously treated with a DAA-containing regimen. In POLARIS-1, patients with HCV genotype 1 infection who had previously received a regimen containing an NS5A inhibitor were randomly assigned in a 1:1 ratio to receive either the nucleotide polymerase inhibitor sofosbuvir, the NS5A inhibitor velpatasvir, and the protease inhibitor voxilaprevir (150 patients) or matching placebo (150 patients) once daily for 12 weeks. Patients who were infected with HCV of other genotypes (114 patients) were enrolled in the sofosbuvir-velpatasvir-voxilaprevir group. In POLARIS-4, patients with HCV genotype 1, 2, or 3 infection who had previously received a DAA regimen but not an NS5A inhibitor were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir-voxilaprevir (163 patients) or sofosbuvir-velpatasvir (151 patients) for 12 weeks. An additional 19 patients with HCV genotype 4 infection were enrolled in the sofosbuvir-velpatasvir-voxilaprevir group. In the three active-treatment groups, 46% of the patients had compensated cirrhosis. In POLARIS-1, the rate of sustained virologic response was 96% with sofosbuvir-velpatasvir-voxilaprevir, as compared with 0% with placebo. In POLARIS-4, the rate of response was 98% with sofosbuvir-velpatasvir-voxilaprevir and 90% with sofosbuvir-velpatasvir. The most common adverse events were headache, fatigue, diarrhea, and nausea. In the active-treatment groups in both trials, the percentage of patients who discontinued treatment owing to adverse events was 1% or lower. Sofosbuvir-velpatasvir-voxilaprevir taken for 12 weeks provided high rates of sustained virologic response among patients across HCV genotypes in whom treatment with a DAA regimen

  4. Preclinical evaluation of an anti-HCV miRNA cluster for treatment of HCV infection.

    Science.gov (United States)

    Yang, Xiao; Marcucci, Katherine; Anguela, Xavier; Couto, Linda B

    2013-03-01

    We developed a strategy to treat hepatitis C virus (HCV) infection by replacing five endogenous microRNA (miRNA) sequences of a natural miRNA cluster (miR-17-92) with sequences that are complementary to the HCV genome. This miRNA cluster (HCV-miR-Cluster 5) is delivered to cells using adeno-associated virus (AAV) vectors and the miRNAs are expressed in the liver, the site of HCV replication and assembly. AAV-HCV-miR-Cluster 5 inhibited bona fide HCV replication in vitro by up to 95% within 2 days, and the spread of HCV to uninfected cells was prevented by continuous expression of the anti-HCV miRNAs. Furthermore, the number of cells harboring HCV RNA replicons decreased dramatically by sustained expression of the anti-HCV miRNAs, suggesting that the vector is capable of curing cells of HCV. Delivery of AAV-HCV-miR-Cluster 5 to mice resulted in efficient transfer of the miRNA gene cluster and expression of all five miRNAs in liver tissue, at levels up to 1,300 copies/cell. These levels achieved up to 98% gene silencing of cognate HCV sequences, and no liver toxicity was observed, supporting the safety of this approach. Therefore, AAV-HCV-miR-Cluster 5 represents a different paradigm for the treatment of HCV infection.

  5. Retreatment efficacy and predictors of ledipasvir plus sofosbuvir to HCV genotype 1 in Japan.

    Science.gov (United States)

    Akuta, Norio; Sezaki, Hitomi; Suzuki, Fumitaka; Fujiyama, Shunichiro; Kawamura, Yusuke; Hosaka, Tetsuya; Kobayashi, Masahiro; Kobayashi, Mariko; Saitoh, Satoshi; Suzuki, Yoshiyuki; Arase, Yasuji; Ikeda, Kenji; Kumada, Hiromitsu

    2017-02-01

    Predictors of treatment efficacy with ledipasvir plus sofosbuvir as direct-acting antiviral (DAA) regimen for HCV infection are still unclear. Retreatment efficacy of ledipasvir plus sofosbuvir for failures to prior DAA regimens, including NS5A inhibitors, are also unknown because resistance-associated variants (RAVs) in NS5A have been shown to persist up to the long-term of post-treatment. One hundred seventy-five patients with chronic HCV genotype 1 infection, without decompensated liver cirrhosis and hepatocellular carcinoma, were evaluated SVR12 by ledipasvir 90 mg plus sofosbuvir 400 mg once-daily for 12 weeks. Overall, SVR12 were 92%, based on intention to treat analysis. In failures to daclatasvir plus asunaprevir, SVR12 were 71%. The study using ultra-deep sequencing showed that ledipasvir plus sofosbuvir was effective to one case of failures to daclatasvir plus asunaprevir with multidrug RAVs (triple mutation in NS3-D168/NS5A-L31/NS5A-Y93). Multivariate analysis identified FIB4 index (ledipasvir plus sofosbuvir for HCV genotype 1 infection, including multidrug RAVs in Japan. Treatment efficacy could be predicted by the combination of viral and host factors. J. Med. Virol. 89:284-290, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. HCV Infection and B-Cell Lymphomagenesis

    Directory of Open Access Journals (Sweden)

    Masahiko Ito

    2011-01-01

    Full Text Available Hepatitis C virus (HCV has been recognized as a major cause of chronic liver diseases worldwide. It has been suggested that HCV infects not only hepatocytes but also mononuclear lymphocytes including B cells that express the CD81 molecule, a putative HCV receptor. HCV infection of B cells is the likely cause of B-cell dysregulation disorders such as mixed cryoglobulinemia, rheumatoid factor production, and B-cell lymphoproliferative disorders that may evolve into non-Hodgkin's lymphoma (NHL. Epidemiological data indicate an association between HCV chronic infection and the occurrence of B-cell NHL, suggesting that chronic HCV infection is associated at least in part with B-cell lymphomagenesis. In this paper, we aim to provide an overview of recent literature, including our own, to elucidate a possible role of HCV chronic infection in B-cell lymphomagenesis.

  7. Structure-guided fragment-based in silico drug design of dengue protease inhibitors

    Science.gov (United States)

    Knehans, Tim; Schüller, Andreas; Doan, Danny N.; Nacro, Kassoum; Hill, Jeffrey; Güntert, Peter; Madhusudhan, M. S.; Weil, Tanja; Vasudevan, Subhash G.

    2011-03-01

    An in silico fragment-based drug design approach was devised and applied towards the identification of small molecule inhibitors of the dengue virus (DENV) NS2B-NS3 protease. Currently, no DENV protease co-crystal structure with bound inhibitor and fully formed substrate binding site is available. Therefore a homology model of DENV NS2B-NS3 protease was generated employing a multiple template spatial restraints method and used for structure-based design. A library of molecular fragments was derived from the ZINC screening database with help of the retrosynthetic combinatorial analysis procedure (RECAP). 150,000 molecular fragments were docked to the DENV protease homology model and the docking poses were rescored using a target-specific scoring function. High scoring fragments were assembled to small molecule candidates by an implicit linking cascade. The cascade included substructure searching and structural filters focusing on interactions with the S1 and S2 pockets of the protease. The chemical space adjacent to the promising candidates was further explored by neighborhood searching. A total of 23 compounds were tested experimentally and two compounds were discovered to inhibit dengue protease (IC50 = 7.7 μM and 37.9 μM, respectively) and the related West Nile virus protease (IC50 = 6.3 μM and 39.0 μM, respectively). This study demonstrates the successful application of a structure-guided fragment-based in silico drug design approach for dengue protease inhibitors providing straightforward hit generation using a combination of homology modeling, fragment docking, chemical similarity and structural filters.

  8. Structure-guided fragment-based in silico drug design of dengue protease inhibitors.

    Science.gov (United States)

    Knehans, Tim; Schüller, Andreas; Doan, Danny N; Nacro, Kassoum; Hill, Jeffrey; Güntert, Peter; Madhusudhan, M S; Weil, Tanja; Vasudevan, Subhash G

    2011-03-01

    An in silico fragment-based drug design approach was devised and applied towards the identification of small molecule inhibitors of the dengue virus (DENV) NS2B-NS3 protease. Currently, no DENV protease co-crystal structure with bound inhibitor and fully formed substrate binding site is available. Therefore a homology model of DENV NS2B-NS3 protease was generated employing a multiple template spatial restraints method and used for structure-based design. A library of molecular fragments was derived from the ZINC screening database with help of the retrosynthetic combinatorial analysis procedure (RECAP). 150,000 molecular fragments were docked to the DENV protease homology model and the docking poses were rescored using a target-specific scoring function. High scoring fragments were assembled to small molecule candidates by an implicit linking cascade. The cascade included substructure searching and structural filters focusing on interactions with the S1 and S2 pockets of the protease. The chemical space adjacent to the promising candidates was further explored by neighborhood searching. A total of 23 compounds were tested experimentally and two compounds were discovered to inhibit dengue protease (IC(50) = 7.7 μM and 37.9 μM, respectively) and the related West Nile virus protease (IC(50) = 6.3 μM and 39.0 μM, respectively). This study demonstrates the successful application of a structure-guided fragment-based in silico drug design approach for dengue protease inhibitors providing straightforward hit generation using a combination of homology modeling, fragment docking, chemical similarity and structural filters.

  9. HIV protease inhibitor resistance

    NARCIS (Netherlands)

    Wensing, Annemarie M.J.; Fun, Axel; Nijhuis, Monique

    2017-01-01

    HIV protease is pivotal in the viral replication cycle and directs the formation of mature infectious virus particles. The development of highly specific HIV protease inhibitors (PIs), based on thorough understanding of the structure of HIV protease and its substrate, serves as a prime example of

  10. HBV And HCV Molecular Evolution

    Directory of Open Access Journals (Sweden)

    Flor H. Pujol

    2007-02-01

    hepatitis C virus (HCV. Six genotypes and a large number of subtypes in each genotype have been described for this member of the Flaviviridae family. Infections with HCV genotype 1 are associated with the lowest therapeutic success. HCV genotype 1b has also been more frequently associated with a more severe liver disease. However, this association seems to be due to the fact that individuals infected with this genotype have a longer mean duration of infection. HCV genotypes 1, 2, and 3 have a worldwide distribution and display an apidemic pattern of distribution. HCV subtypes 1a and 1b are the most common genotypes in the United States and are also are predominant in Europe, while in Japan, subtype 1b is predominant. Although HCV subtypes 2a and 2b are relatively common in America, Europe, and Japan, subtype 2c is found commonly in northern Italy. HCV genotype 3a is frequent in intravenous drug abusers in Europe and the United States. HCV genotype 4 appears to be prevalent in Africa and theMiddle East, and genotypes 5 and 6 seem to be confined to South Africa and Asia, respectively. These last genotypes display an endemic pattern of distribution. In addition, a change in the frequency of the prevailing genotypes has been described in several countries: in general, HCV genotype 1b is being displaced by genotypes 3a and/or 2. Coalescent studies have allowed to describe the epidemic pattern of dissemination of some HCV subtypes in specific countries, generally around 100 years ago. The origin of this virus is still an open question, but several studies traces it diversification only around 1,000 years ago.

    The replication of HCV is dependent on a RNA-polymerase RNA dependent which lacks proofreading activity, which confers to this virus a high rate of variability. This virus circulates as a quasispecies. This population dynamic inside a single strain confers to this virus the ability to

  11. Serotype-specific interactions among functional domains of dengue virus 2 nonstructural proteins (NS) 5 and NS3 are crucial for viral RNA replication.

    Science.gov (United States)

    Teramoto, Tadahisa; Balasubramanian, Anuradha; Choi, Kyung H; Padmanabhan, Radhakrishnan

    2017-06-09

    Four serotypes of mosquito-borne dengue virus (DENV), evolved from a common ancestor, are human pathogens of global significance for which there is no vaccine or antiviral drug available. The N-terminal domain of DENV NS5 has guanylyltransferase and methyltransferase (MTase), and the C-terminal region has the polymerase (POL), all of which are important for 5'-capping and RNA replication. The crystal structure of NS5 shows it as a dimer, but the functional evidence for NS5 dimer is lacking. Our studies showed that the substitution of DENV2 NS5 MTase or POL for DENV4 NS5 within DENV2 RNA resulted in a severe attenuation of replication in the transfected BHK-21 cells. A replication-competent species was evolved with the acquired mutations in the DENV2 and DENV4 NS5 MTase or POL domain or in the DENV2 NS3 helicase domain in the DENV2 chimera RNAs by repeated passaging of infected BHK-21 or mosquito cells. The linker region of seven residues in NS5, rich in serotype-specific residues, is important for the recovery of replication fitness in the chimera RNA. Our results, taken together, provide genetic evidence for a serotype-specific interaction between NS3 and NS5 as well as specific interdomain interaction within NS5 required for RNA replication. Genome-wide RNAseq analysis revealed the distribution of adaptive mutations in RNA quasispecies. Those within NS3 and NS5 are located at the surface and/or within the NS5 dimer interface, providing a functional significance to the crystal structure NS5 dimer. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. NS4A protein as a marker of HCV history suggests that different HCV genotypes originally evolved from genotype 1b

    Science.gov (United States)

    2011-01-01

    Background The 9.6 kb long RNA genome of Hepatitis C virus (HCV) is under the control of RNA dependent RNA polymerase, an error-prone enzyme, for its transcription and replication. A high rate of mutation has been found to be associated with RNA viruses like HCV. Based on genetic variability, HCV has been classified into 6 different major genotypes and 11 different subtypes. However this classification system does not provide significant information about the origin of the virus, primarily due to high mutation rate at nucleotide level. HCV genome codes for a single polyprotein of about 3011 amino acids which is processed into structural and non-structural proteins inside host cell by viral and cellular proteases. Results We have identified a conserved NS4A protein sequence for HCV genotype 3a reported from four different continents of the world i.e. Europe, America, Australia and Asia. We investigated 346 sequences and compared amino acid composition of NS4A protein of different HCV genotypes through Multiple Sequence Alignment and observed amino acid substitutions C22, V29, V30, V38, Q46 and Q47 in NS4A protein of genotype 1b. Furthermore, we observed C22 and V30 as more consistent members of NS4A protein of genotype 1a. Similarly Q46 and Q47 in genotype 5, V29, V30, Q46 and Q47 in genotype 4, C22, Q46 and Q47 in genotype 6, C22, V38, Q46 and Q47 in genotype 3 and C22 in genotype 2 as more consistent members of NS4A protein of these genotypes. So the different amino acids that were introduced as substitutions in NS4A protein of genotype 1 subtype 1b have been retained as consistent members of the NS4A protein of other known genotypes. Conclusion These observations indicate that NS4A protein of different HCV genotypes originally evolved from NS4A protein of genotype 1 subtype 1b, which in turn indicate that HCV genotype 1 subtype 1b established itself earlier in human population and all other known genotypes evolved later as a result of mutations in HCV genotype 1b

  13. Potential for Drug-Drug Interactions between Antiretrovirals and HCV Direct Acting Antivirals in a Large Cohort of HIV/HCV Coinfected Patients.

    Directory of Open Access Journals (Sweden)

    Isabelle Poizot-Martin

    Full Text Available Development of direct acting antivirals (DAA offers new benefits for patients with chronic hepatitis C. The combination of these drugs with antiretroviral treatment (cART is a real challenge in HIV/HCV coinfected patients. The aim of this study was to describe potential drug-drug interactions between DAAs and antiretroviral drugs in a cohort of HIV/HCV coinfected patients.Cross-sectional study of all HIV/HCV coinfected patients attending at least one visit in 2012 in the multicenter French Dat'AIDS cohort. A simulation of drug-drug interactions between antiretroviral treatment and DAAs available in 2015 was performed.Of 16,634 HIV-infected patients, 2,511 had detectable anti-HCV antibodies, of whom 1,196 had a detectable HCV-RNA and were not receiving HCV treatment at the time of analysis. 97.1% of these patients were receiving cART and 81.2% had a plasma HIV RNA <50 copies/mL. cART included combinations of nucleoside reverse transcriptase inhibitors with a boosted protease inhibitor in 43.6%, a non-nucleoside reverse transcriptase inhibitor in 17.3%, an integrase inhibitor in 15.4% and various combinations or antiretroviral drugs in 23.7% of patients. A previous treatment against HCV had been administered in 64.4% of patients. Contraindicated associations/potential interactions were expected between cART and respectively sofosbuvir (0.2%/0%, sofosbuvir/ledipasvir (0.2%/67.6%, daclatasvir (0%/49.4%, ombitasvir/boosted paritaprevir (with or without dasabuvir (34.4%/52.2% and simeprevir (78.8%/0%.Significant potential drug-drug interactions are expected between cART and the currently available DAAs in the majority of HIV/HCV coinfected patients. Sofosbuvir/ledipasvir and sofosbuvir/daclatasvir with or without ribavirin appeared the most suitable combinations in our population. A close collaboration between hepatologists and HIV/AIDS specialists appears necessary for the management of HCV treatment concomitantly to cART.

  14. NS4A protein as a marker of HCV history suggests that different HCV genotypes originally evolved from genotype 1b

    Directory of Open Access Journals (Sweden)

    Asad Sultan

    2011-06-01

    Full Text Available Abstract Background The 9.6 kb long RNA genome of Hepatitis C virus (HCV is under the control of RNA dependent RNA polymerase, an error-prone enzyme, for its transcription and replication. A high rate of mutation has been found to be associated with RNA viruses like HCV. Based on genetic variability, HCV has been classified into 6 different major genotypes and 11 different subtypes. However this classification system does not provide significant information about the origin of the virus, primarily due to high mutation rate at nucleotide level. HCV genome codes for a single polyprotein of about 3011 amino acids which is processed into structural and non-structural proteins inside host cell by viral and cellular proteases. Results We have identified a conserved NS4A protein sequence for HCV genotype 3a reported from four different continents of the world i.e. Europe, America, Australia and Asia. We investigated 346 sequences and compared amino acid composition of NS4A protein of different HCV genotypes through Multiple Sequence Alignment and observed amino acid substitutions C22, V29, V30, V38, Q46 and Q47 in NS4A protein of genotype 1b. Furthermore, we observed C22 and V30 as more consistent members of NS4A protein of genotype 1a. Similarly Q46 and Q47 in genotype 5, V29, V30, Q46 and Q47 in genotype 4, C22, Q46 and Q47 in genotype 6, C22, V38, Q46 and Q47 in genotype 3 and C22 in genotype 2 as more consistent members of NS4A protein of these genotypes. So the different amino acids that were introduced as substitutions in NS4A protein of genotype 1 subtype 1b have been retained as consistent members of the NS4A protein of other known genotypes. Conclusion These observations indicate that NS4A protein of different HCV genotypes originally evolved from NS4A protein of genotype 1 subtype 1b, which in turn indicate that HCV genotype 1 subtype 1b established itself earlier in human population and all other known genotypes evolved later as a result of

  15. Impact of Pre-existing NS5A-L31 or -Y93H Minor Variants on Response Rates in Patients Infected with HCV Genotype-1b Treated with Daclatasvir/Asunaprevir.

    Science.gov (United States)

    Hernandez, Dennis; Yu, Fei; Huang, Xin; Kirov, Stefan; Pant, Saumya; McPhee, Fiona

    2016-07-01

    The combination of daclatasvir (DCV, pan-genotypic NS5A inhibitor) plus asunaprevir (ASV; NS3 protease inhibitor) is approved in Japan, Korea and other countries for the treatment of chronic hepatitis C virus (HCV) genotype (GT)-1. A high (~90 to 100%) sustained virologic response (SVR) with DCV/ASV therapy has been achieved by excluding patients infected with HCV GT-1b with baseline NS5A resistance-associated variants (RAVs) at L31 or Y93H detected by direct sequencing (DS). We set out to determine whether patients with minor variants at NS5A-L31 or -Y93H, detected by next-generation sequencing (NGS), impacted SVR rates with DCV/ASV therapy. Baseline samples from 222 interferon (IFN)-ineligible/intolerant (N = 135) and prior non-responder (N = 87) patients infected with GT-1b who were treated with DCV/ASV for 24 weeks in the Phase 3 clinical study AI447026 were prepared for NGS (Ion-Torrent platform). The prevalence of baseline NS5A RAVs and their impact on SVR when observed at ≥1% by NGS in a patient's virus population were examined. NGS and DS (sensitivity ≥20%) data were compared. The prevalence of baseline NS5A RAVs at L31 or Y93H was 29% (63/219) and 18% (39/214) by NGS and DS, respectively. SVR24 rates were comparable in patients without observed baseline L31 or Y93H polymorphisms whether assessed by NGS (96%; 148/154) or by the less sensitive DS platform (95%; 164/173). Optimal SVR rates (≥95%) to DCV/ASV treatment were achieved using DS to exclude patients infected with GT-1b with NS5A RAVs at L31 or Y93H representing ≥20% of their virus population. Exclusion by NGS of patients with minor variants in NS5A (<20%) did not enhance SVR rates. These results suggest that the presence of minor variants in NS5A does not appear to impact the overall SVR rate in patients with GT-1b treated with DCV/ASV. This study was sponsored by Bristol-Myers Squibb. ClinicalTrials.gov identifier: NCT01497834.

  16. Complementary role of HCV and HIV in T-cell activation and exhaustion in HIV/HCV coinfection

    NARCIS (Netherlands)

    Feuth, T.; Arends, J.E.; Fransen, J.H.; Nanlohy, N.M.; Erpecum, K.J. van; Siersema, P.D.; Hoepelman, A.I.; Baarle, D. van

    2013-01-01

    OBJECTIVES: To investigate whether T-cell activation and exhaustion is linked to HCV- and HIV disease parameters in HIV/HCV infected individuals, we studied T-cell characteristics in HIV/HCV coinfected patients and controls. METHODS: 14 HIV/HCV coinfected, 19 HCV monoinfected, 10 HIV monoinfected

  17. Expression of the rice hoja blanca virus (RHBV) non-structural protein 3 (NS3) in Escherichia coli and its in situ localization in RHBV-infected rice tissues.

    Science.gov (United States)

    Muñoz, Miguel; Bolaños, Isela; Arrieta-Espinoza, Griselda; Espinoza, Ana M

    2004-09-01

    The non-structural NS3 protein gene from the rice hoja blanca virus (RHBV) was fused to the glutathione-S-transferase carboxilic end and expressed in Escherichia coli strain JM83. Large quantities of fusion protein were produced in insoluble form. The fusion protein was fractionated in SDS-PAGE and purified by electroelution, polyclonal antibodies were raised in rabbit and the antiserum was absorbed with bacterial crude extract. A band of similar size as that of NS3 protein was observed in Western blots using extracts from RHBV-infected rice plants. Immunoelectron microscopy with colloidal gold-labeled antibodies against NS3 protein and the viral nucleocapsid protein revealed in situ accumulation of NS3 protein in the cytoplasm but not in the viral inclusion bodies, vacuoles or chloroplasts of RHBV-infected plants, following the same pattern of distribution as the RHBV nucleocapsid protein.

  18. Serotype-Specific Structural Differences in the Protease-Cofactor Complexes of the Dengue Virus Family

    Energy Technology Data Exchange (ETDEWEB)

    Chandramouli, Sumana; Joseph, Jeremiah S.; Daudenarde, Sophie; Gatchalian, Jovylyn; Cornillez-Ty, Cromwell; Kuhn, Peter (Scripps)

    2010-03-04

    With an estimated 40% of the world population at risk, dengue poses a significant threat to human health, especially in tropical and subtropical regions. Preventative and curative efforts, such as vaccine development and drug discovery, face additional challenges due to the occurrence of four antigenically distinct serotypes of the causative dengue virus (DEN1 to -4). Complex immune responses resulting from repeat assaults by the different serotypes necessitate simultaneous targeting of all forms of the virus. One of the promising targets for drug development is the highly conserved two-component viral protease NS2B-NS3, which plays an essential role in viral replication by processing the viral precursor polyprotein into functional proteins. In this paper, we report the 2.1-{angstrom} crystal structure of the DEN1 NS2B hydrophilic core (residues 49 to 95) in complex with the NS3 protease domain (residues 1 to 186) carrying an internal deletion in the N terminus (residues 11 to 20). While the overall folds within the protease core are similar to those of DEN2 and DEN4 proteases, the conformation of the cofactor NS2B is dramatically different from those of other flaviviral apoprotease structures. The differences are especially apparent within its C-terminal region, implicated in substrate binding. The structure reveals for the first time serotype-specific structural elements in the dengue virus family, with the reported alternate conformation resulting from a unique metal-binding site within the DEN1 sequence. We also report the identification of a 10-residue stretch within NS3pro that separates the substrate-binding function from the catalytic turnover rate of the enzyme. Implications for broad-spectrum drug discovery are discussed.

  19. The history of hepatitis C virus (HCV)

    DEFF Research Database (Denmark)

    Bukh, Jens

    2016-01-01

    The discovery of hepatitis C virus (HCV) in 1989 permitted basic research to unravel critical components of a complex life cycle for this important human pathogen. HCV is a highly divergent group of viruses classified in 7 major genotypes and a great number of subtypes, and circulating in infected...

  20. Hepatitis C virus (HCV) RNA profiles among chronic HIV/HCV-coinfected individuals in ESPRIT; spontaneous HCV RNA clearance observed in nine individuals

    DEFF Research Database (Denmark)

    Grint, D; Tedaldi, Ellen; Peters, L

    2017-01-01

    with the CC interleukin (IL)-28B genotype. This study describes HCV RNA profiles and factors associated with changes over time in HCV RNA levels in the ESPRIT study. METHODS: HIV/HCV-coinfected individuals positive for HCV RNA were included in the study. Follow-up was counted from the first HCV RNA positive...... test and censored at the initiation of interferon-based treatment. HCV RNA and IL-28B measurements were performed in the same reference laboratory. Random effects mixed models were used to analyse changes over time in HCV RNA. RESULTS: A total of 312 ESPRIT patients were included in the study (151...

  1. Expression of the rice hoja blanca virus (RHBV non-structural protein 3 (NS3 in Escherichia coli and its in situ localization in RHBV-infected rice tissues

    Directory of Open Access Journals (Sweden)

    Miguel Muñoz

    2004-09-01

    Full Text Available The non-structural NS3 protein gene from the rice hoja blanca virus (RHBV was fused to the glutathione- S-transferase carboxilic end and expressed in Escherichia coli strain JM83. Large quantities of fusion protein were produced in insoluble form. The fusion protein was fractionated in SDS-PAGE and purified by electroelution, polyclonal antibodies were raised in rabbit and the antiserum was absorbed with bacterial crude extract. A band of similar size as that of NS3 protein was observed in Western blots using extracts from RHBV-infected rice plants. Immunoelectron microscopy with colloidal gold-labeled antibodies against NS3 protein and the viral nucleocapsid protein revealed in situ accumulation of NS3 protein in the cytoplasm but not in the viral inclusion bodies, vacuoles or chloroplasts of RHBV-infected plants, following the same pattern of distribution as the RHBV nucleocapsid protein. Rev. Biol. Trop. 52(3: 765-775. Epub 2004 Dic 15.El gen que codifica por la proteína no estructural NS3 del virus de la hoja blanca de arroz (RHBV se fusionó al extremo carboxilo del gen de la glutationa-S-transferasa y se expresó en la cepa JM83 de Escherichia coli. Se obtuvieron altas concentraciones de la proteína de fusion (GST-NS3 en forma insoluble. La proteína de fusión se fraccionó en geles de SDS-PAGE, se purificó por electroelución, y se utilizó para producir anticuerpos policlonales en conejo . El antisuero producido se absorbió con extractos crudos de E. coli. Extractos crudos de plantas de arroz sanas e infectadas con el RHBV se evaluaron por Western blots detectándose una banda de peso molecular similar al estimado para la proteína NS3 (23KDa en las plantas infectadas con el virus. Los tejidos provenientes de plantas infectadas con el RHBV se analizaron por medio de microscopia inmunoelectrónica con oro colloidal marcado con anticuerpos contra la proteína NS3 y la nucleoproteína viral N. Se observó una acumulación in situ de la

  2. Novel fungal protease.

    NARCIS (Netherlands)

    Buxton, F.; Jarai, G.; Visser, J.

    1994-01-01

    The present invention concerns a novel DNA sequence coding for an Aspergillus serine protease of the subtilisin-type, an Aspergillus serine protease of the subtilisin-type per se and a method for the preparation thereof. The invention further concerns a novel Aspergillus mutant strain defective in a

  3. Sexual Transmission of HCV in Heterologous Monogamous Spouses

    Directory of Open Access Journals (Sweden)

    Mona M. Rafik

    2014-01-01

    Full Text Available We screened for evidence of HCV infection in healthy heterologous monogamous spouses of chronic HCV patients and studied the relation with various risk factors. A cross-sectional study of fifty healthy monogamous heterosexual spouses of HCV-positive index cases was carried out. All participants were HBV and HIV negative. The association with various risk factors was studied. Five spouses (10% showed evidence of HCV infection. Two partners were positive for HCV antibody alone (4% and 3 for antibody and HCV PCR (6%. No association was found between HCV infection and various sociodemographic parameters with the exception of older age categories. Intraspousal transmission of HCV may be an important source of spread of HCV infection. The reservoir of HCV-infected individuals in Egypt is sizable, and sexual transmission of HCV may contribute to the total burden of infection in Egypt.

  4. Resistance Patterns Associated with HCV NS5A Inhibitors Provide Limited Insight into Drug Binding

    Directory of Open Access Journals (Sweden)

    Moheshwarnath Issur

    2014-11-01

    Full Text Available Direct-acting antivirals (DAAs have significantly improved the treatment of infection with the hepatitis C virus. A promising class of novel antiviral agents targets the HCV NS5A protein. The high potency and broad genotypic coverage are favorable properties. NS5A inhibitors are currently assessed in advanced clinical trials in combination with viral polymerase inhibitors and/or viral protease inhibitors. However, the clinical use of NS5A inhibitors is also associated with new challenges. HCV variants with decreased susceptibility to these drugs can emerge and compromise therapy. In this review, we discuss resistance patterns in NS5A with focus prevalence and implications for inhibitor binding.

  5. HCV-induced autophagosomes are generated via homotypic fusion of phagophores that mediate HCV RNA replication.

    Directory of Open Access Journals (Sweden)

    Linya Wang

    2017-09-01

    Full Text Available Hepatitis C virus (HCV induces autophagy to promote its replication, including its RNA replication, which can take place on double-membrane vesicles known as autophagosomes. However, how HCV induces the biogenesis of autophagosomes and how HCV RNA replication complex may be assembled on autophagosomes were largely unknown. During autophagy, crescent membrane structures known as phagophores first appear in the cytoplasm, which then progress to become autophagosomes. By conducting electron microscopy and in vitro membrane fusion assay, we found that phagophores induced by HCV underwent homotypic fusion to generate autophagosomes in a process dependent on the SNARE protein syntaxin 7 (STX7. Further analyses by live-cell imaging and fluorescence microscopy indicated that HCV-induced phagophores originated from the endoplasmic reticulum (ER. Interestingly, comparing with autophagy induced by nutrient starvation, the progression of phagophores to autophagosomes induced by HCV took significantly longer time, indicating fundamental differences in the biogenesis of autophagosomes induced by these two different stimuli. As the knockdown of STX7 to inhibit the formation of autophagosomes did not affect HCV RNA replication, and purified phagophores could mediate HCV RNA replication, the assembly of the HCV RNA replication complex on autophagosomes apparently took place during the formative stage of phagophores. These findings provided important information for understanding how HCV controlled and modified this important cellular pathway for its own replication.

  6. Hepatitis C virus genotypes in Tirana, Albania.

    Science.gov (United States)

    Haldeda, Migena; Baume, Julien; Tamalet, Catherine; Bizhga, Melpomeni; Colson, Philippe

    2014-01-01

    Hepatitis C virus (HCV) infection is a worldwide concern. Knowledge of the HCV genotype is clinically important because it predicts the rate of response to therapy and guides the treatment duration. Moreover, it allows molecular epidemiology to be performed. To our knowledge, the prevalence of HCV genotypes has been assessed only once in Albania, using a line probe genotyping assay. We determined HCV genotypes by population sequencing of HCV-infected patients in Tirana, Albania. HCV genotype and sequence analyses were performed for serum samples collected from January 2011 through May 2012 from 61 HCV-seropositive patients using population sequencing of the NS3 protease gene and alternatively the NS5b gene and the 5' untranslated region (UTR). HCV RNA was retrieved from the blood samples of 50 patients. The HCV NS3 protease gene was sequenced for 28 patients and NS5b and/or 5'UTR fragments were sequenced for an additional 22 patients. The predominant genotype was 1b in 25 patients (50%), followed by genotypes 2c, 4a, 3a, and 1a in 18%, 14%, 8%, and 6% of cases, respectively. Best matches for these HCV RNAs in GenBank were obtained in different countries worldwide. One NS3 protease naturally harbored an amino acid conferring minor drug resistance to newly available HCV protease inhibitors. In conclusion, HCV-1b was predominant in the present Albanian population, as in southeastern Europe. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Molecular Epidemiology of Hepatitis C Virus (HCV) in Kadun State ...

    African Journals Online (AJOL)

    Objective: To determine the distribution of hepatitis C virus (HCV) genotypes and subtypes among blood donors and outpatients attendees positive for antibody to HCV (anti-HCV). Justification: Hepatitis C virus (HCV) continues to be a major disease burden on the world and Man is the only known natural host of Hepatitis C ...

  8. The Novel Cyclophilin Inhibitor CPI-431-32 Concurrently Blocks HCV and HIV-1 Infections via a Similar Mechanism of Action.

    Directory of Open Access Journals (Sweden)

    Philippe A Gallay

    Full Text Available HCV-related liver disease is the main cause of morbidity and mortality of HCV/HIV-1 co-infected patients. Despite the recent advent of anti-HCV direct acting antivirals (DAAs, the treatment of HCV/HIV-1 co-infected patients remains a challenge, as these patients are refractory to most therapies and develop liver fibrosis, cirrhosis and liver cancer more often than HCV mono-infected patients. Until the present study, there was no suitable in vitro assay to test the inhibitory activity of drugs on HCV/HIV-1 co-infection. Here we developed a novel in vitro "co-infection" model where HCV and HIV-1 concurrently replicate in their respective main host target cells--human hepatocytes and CD4+ T-lymphocytes. Using this co-culture model, we demonstrate that cyclophilin inhibitors (CypI, including a novel cyclosporin A (CsA analog, CPI-431-32, simultaneously inhibits replication of both HCV and HIV-1 when added pre- and post-infection. In contrast, the HIV-1 protease inhibitor nelfinavir or the HCV NS5A inhibitor daclatasvir only blocks the replication of a single virus in the "co-infection" system. CPI-431-32 efficiently inhibits HCV and HIV-1 variants, which are normally resistant to DAAs. CPI-431-32 is slightly, but consistently more efficacious than the most advanced clinically tested CypI--alisporivir (ALV--at interrupting an established HCV/HIV-1 co-infection. The superior antiviral efficacy of CPI-431-32 over ALV correlates with its higher potency inhibition of cyclophilin A (CypA isomerase activity and at preventing HCV NS5A-CypA and HIV-1 capsid-CypA interactions known to be vital for replication of the respective viruses. Moreover, we obtained evidence that CPI-431-32 prevents the cloaking of both the HIV-1 and HCV genomes from cellular sensors. Based on these results, CPI-431-32 has the potential, as a single agent or in combination with DAAs, to inhibit both HCV and HIV-1 infections.

  9. Hepatitis B and Hepatitis C Virus Replication Upregulates Serine Protease Inhibitor Kazal, Resulting in Cellular Resistance to Serine Protease-Dependent Apoptosis▿ †

    OpenAIRE

    Lamontagne, Jason; Pinkerton, Mark; Timothy M Block; Lu, Xuanyong

    2009-01-01

    Hepatitis B and C viruses (HBV and HCV, respectively) are different and distinct viruses, but there are striking similarities in their disease potential. Infection by either virus can cause chronic hepatitis, liver cirrhosis, and ultimately, liver cancer, despite the fact that no pathogenetic mechanisms are known which are shared by the two viruses. Our recent studies have suggested that replication of either of these viruses upregulates a cellular protein called serine protease inhibitor Kaz...

  10. Interaction of lipidated GBV-C/HGV NS3 (513-522) and (505-514) peptides with phospholipids monolayer. An AFM study.

    Science.gov (United States)

    Weroński, Konrad J; Diez-Pérez, Ismael; Busquets, M Antonia; López-Iglesias, Carmen; Girona, Victoria; Prat, Josefina

    2010-01-01

    Lipidation of a short hydrophilic peptide has the aim to make the molecule amphiphilic, which improves its insertion into lipid monolayer and at the same time, the tendency to self-assembly. These both properties of two positively charged, hepatitis G (GBV-C/HGV) related lipidated peptides--palmitic acid derivatives of the fragments: 505-514 and the 513-522 of the NS3 protein (respectively Palmitoyl-SAELSMQRRG and Palmitoyl-RGRTGRGRSG) were studied. First, using transmission electron microscope (TEM) and atomic force microscope (AFM) the tendency to self-assembly in water solution was examined. Both techniques confirmed the formation of fibrous aggregates of Palmitoyl-SAELSMQRRG in water solution. At the same conditions, any fibrous aggregates of Palmitoyl-RGRTGRGRSG were detected neither by TEM nor by AFM. Insertion of the lipidated peptides into phospholipids monolayer formed by zwitterionic 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or negatively charged 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (DPPG) was investigated. Monolayers prepared by Langmuir-Blodgett method were visualized by AFM. The presence of lipidated peptides in phospholipid monolayers produced changes in the monolayers and different morphologies of the monolayers were obtained for each of the lipidated peptides.

  11. Efficient infectious cell culture systems of the hepatitis C virus (HCV) prototype strains HCV-1 and H77

    DEFF Research Database (Denmark)

    Li, Yi-Ping; Ramirez, Santseharay; Mikkelsen, Lotte

    2015-01-01

    UNLABELLED: The first discovered and sequenced hepatitis C virus (HCV) genome and the first in vivo infectious HCV clones originated from the HCV prototype strains HCV-1 and H77, respectively, both widely used in research of this important human pathogen. In the present study, we developed...... efficiently after transfection and subsequent infection of naive Huh7.5 cells, reaching titers of 10(3.5) and 10(4.4) FFU/ml, respectively. IMPORTANCE: Hepatitis C virus (HCV) was discovered in 1989 with the cloning of the prototype strain HCV-1 genome. In 1997, two molecular clones of H77, the other HCV...

  12. Telaprevir-containing triple therapy in acute HCV coinfection: The CHAT Study.

    Science.gov (United States)

    Boesecke, Christoph; Singh, Gurmit K Jagjit; Scholten, Stefan H-A; Lutz, Thomas; Baumgarten, Axel; Schneeweiss, Stephan M; Trein, Andreas; Rausch, Michael; Ingiliz, Patrick; Rockstroh, Jürgen K; Nelson, Mark

    2017-01-01

    No published randomized controlled data on the use of direct-acting antivirals (DAA) in acute hepatitis C (AHC) coinfection exist. However, with the AHC epidemic ongoing among men who have sex with men (MSM) these are urgently needed. The CHAT study is a randomized controlled trial of pegylated interferon + ribavirin (PR) plus telaprevir (TVR) for 12-24 weeks versus PR alone for 24-48 weeks in the response-guided treatment of patients with AHC genotype (GT) 1 infection and HIV-1 coinfection in Germany and Great Britain. 34 patients were included: 15 were randomized to the PR arm (arm 1), 19 to the TVR + PR arm (arm 2). All patients were MSM, median age was 40 years. 55% had IL28B C/C GT. Median baseline HCV RNA was 291,227 IU/ml, median alanine aminotransferase was 105 U/l. 85% received cART, all had baseline HIV RNA <40 copies/ml. Overall sustained virological response (SVR 12 ) rate was 79.4% (27/34). SVR 12 was seen in 12/15 (80%) in arm 1 and in 15/19 (79.8%) in arm 2. Of the four patients without SVR in arm 2, one experienced viraI breakthrough, two were non-responders; in one case HCV protease inhibitor (PI)-associated mutations were selected under TVR (V36M, R155K). Due to moderate response rates and additional toxicities 1st generation HCV PIs should not be used in treating acute HCV. While not being licensed, recent study data and guidelines support the use of dual DAA therapy but optimal treatment duration in acute HCV needs further investigation.

  13. Introduction and Utilization of High Priced HCV Medicines across Europe; Implications for the Future

    Science.gov (United States)

    de Bruijn, Winnie; Ibáñez, Cristina; Frisk, Pia; Bak Pedersen, Hanne; Alkan, Ali; Vella Bonanno, Patricia; Brkičić, Ljiljana S.; Bucsics, Anna; Dedet, Guillaume; Eriksen, Jaran; Fadare, Joseph O.; Fürst, Jurij; Gallego, Gisselle; Godói, Isabella P.; Guerra Júnior, Augusto A.; Gürsöz, Hakkı; Jan, Saira; Jones, Jan; Joppi, Roberta; Kerman, Saim; Laius, Ott; Madzikwa, Newman; Magnússon, Einar; Maticic, Mojca; Markovic-Pekovic, Vanda; Massele, Amos; Ogunleye, Olayinka; O'Leary, Aisling; Piessnegger, Jutta; Sermet, Catherine; Simoens, Steven; Tiroyakgosi, Celda; Truter, Ilse; Thyberg, Magnus; Tomekova, Kristina; Wladysiuk, Magdalena; Vandoros, Sotiris; Vural, Elif H.; Zara, Corinne; Godman, Brian

    2016-01-01

    Background: Infection with the Hepatitis C Virus (HCV) is a widespread transmittable disease with a diagnosed prevalence of 2.0%. Fortunately, it is now curable in most patients. Sales of medicines to treat HCV infection grew 2.7% per year between 2004 and 2011, enhanced by the launch of the protease inhibitors (PIs) boceprevir (BCV) and telaprevir (TVR) in addition to ribavirin and pegylated interferon (pegIFN). Costs will continue to rise with new treatments including sofosbuvir, which now include interferon free regimens. Objective: Assess the uptake of BCV and TVR across Europe from a health authority perspective to offer future guidance on dealing with new high cost medicines. Methods: Cross-sectional descriptive study of medicines to treat HCV (pegIFN, ribavirin, BCV and TVR) among European countries from 2008 to 2013. Utilization measured in defined daily doses (DDDs)/1000 patients/quarter (DIQs) and expenditure in Euros/DDD. Health authority activities to influence treatments categorized using the 4E methodology (Education, Engineering, Economics and Enforcement). Results: Similar uptake of BCV and TVR among European countries and regions, ranging from 0.5 DIQ in Denmark, Netherlands and Slovenia to 1.5 DIQ in Tayside and Catalonia in 2013. However, different utilization of the new PIs vs. ribavirin indicates differences in dual vs. triple therapy, which is down to factors including physician preference and genotypes. Reimbursed prices for BCV and TVR were comparable across countries. Conclusion: There was reasonable consistency in the utilization of BCV and TVR among European countries in comparison with other high priced medicines. This may reflect the social demand to limit the transmission of HCV. However, the situation is changing with new curative medicines for HCV genotype 1 (GT1) with potentially an appreciable budget impact. These concerns have resulted in different prices across countries, with their impact on budgets and patient outcomes

  14. Introduction and utilisation of high priced HCV medicines across Europe; implications for the future

    Directory of Open Access Journals (Sweden)

    Winnie de Bruijn

    2016-07-01

    Full Text Available Background: Infection with the Hepatitis C Virus (HCV is a widespread transmittable disease with a diagnosed prevalence of 2.0%. Fortunately, it is now curable in most patients. Sales of medicines to treat HCV infection grew 2.7% per year between 2004 and 2011, enhanced by the launch of the protease inhibitors (PIs boceprevir (BCV and telaprevir (TVR in addition to ribavirin and pegylated interferon (pegIFN. Costs will continue to rise with new treatments including sofosbuvir, which now include interferon free regimens. Objective: Assess the uptake of BCV and TVR across Europe from a health authority perspective to offer future guidance on dealing with new high cost medicines. Methods: Cross-sectional descriptive study of medicines to treat HCV (pegIFN, ribavirin, BCV and TVR among European countries from 2008 to 2013. Utilisation measured in defined daily doses (DDDs/ 1000 patients/ quarter (DIQs and expenditure in Euros/ DDD. Health authority activities to influence treatments categorised using the 4E methodology (Education, Engineering, Economics and Enforcement. Results: Similar uptake of BCV and TVR among European countries and regions, ranging from 0.5 DIQ in Denmark, Netherlands and Slovenia to 1.5 DIQ in Tayside and Catalonia in 2013. However, different utilisation of the new PIs versus ribavirin indicates differences in dual versus triple therapy, which is down to factors including physician preference and genotypes. Reimbursed prices for BCV and TVR were comparable across countries. Conclusion: There was reasonable consistency in the utilisation of BCV and TVR among European countries in comparison with other high priced medicines. This may reflect the social demand to limit the transmission of HCV. However, the situation is changing with new curative medicines for HCV genotype 1 (GT1 with potentially an appreciable budget impact. These concerns have resulted in different prices negotiations across countries, with their impact

  15. Production of recombinant non-structural protein-3 hydrophobic domain deletion (NS3ΔHD) protein of bluetongue virus from prokaryotic expression system as an efficient diagnostic reagent.

    Science.gov (United States)

    Mohanty, Nihar Nalini; Chacko, Nirmal; Biswas, Sanchay Kumar; Chand, Karam; Pandey, Awadh Bihari; Mondal, Bimalendu; Hemadri, Divakar; Shivachandra, Sathish Bhadravati

    2016-09-01

    Serological diagnostics for bluetongue (BT), which is an infectious, non-contagious and arthropod-borne virus disease of ruminants, are primarily dependent on availability of high quality native or recombinant antigen(s) based on either structural/non-structural proteins in sufficient quantity. Non-structural proteins (NS1-NS4) of BT virus are presumed candidate antigens in development of DIVA diagnostics. In the present study, NS3 fusion gene encoding for NS3 protein containing the N- and C-termini with a deletion of two hydrophobic domains (118A to S141 aa and 162S to A182 aa) and intervening variable central domain (142D to K161 aa) of bluetongue virus 23 was constructed, cloned and over-expressed using prokaryotic expression system. The recombinant NS3ΔHD fusion protein (∼38 kDa) including hexa-histidine tag on its both termini was found to be non-cytotoxic to recombinant Escherichia coli cells and purified by affinity chromatography. The purified rNS3ΔHD fusion protein was found to efficiently detect BTV-NS3 specific antibodies in indirect-ELISA format with diagnostic sensitivity (DSn = 94.4%) and specificity (DSp = 93.9%). The study indicated the potential utility of rNS3ΔHD fusion protein as candidate diagnostic reagent in developing an indirect-ELISA for sero-surveillance of animals for BTV antibodies under DIVA strategy, wherever monovalent/polyvalent killed BT vaccine formulations devoid of NS proteins are being practiced for immunization. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  16. Bacterial proteases and virulence

    DEFF Research Database (Denmark)

    Frees, Dorte; Brøndsted, Lone; Ingmer, Hanne

    2013-01-01

    Bacterial pathogens rely on proteolysis for variety of purposes during the infection process. In the cytosol, the main proteolytic players are the conserved Clp and Lon proteases that directly contribute to virulence through the timely degradation of virulence regulators and indirectly by providing....... These extracellular proteases are activated in complex cascades involving auto-processing and proteolytic maturation. Thus, proteolysis has been adopted by bacterial pathogens at multiple levels to ensure the success of the pathogen in contact with the human host....

  17. 12 Weeks of Daclatasvir in Combination With Sofosbuvir for HIV-HCV Coinfection (ALLY-2 Study): Efficacy and Safety by HIV Combination Antiretroviral Regimens.

    Science.gov (United States)

    Luetkemeyer, Anne F; McDonald, Cheryl; Ramgopal, Moti; Noviello, Stephanie; Bhore, Rafia; Ackerman, Peter

    2016-06-15

    Highly effective hepatitis C virus (HCV) direct-acting antiviral therapies that do not require modification of human immunodeficiency virus (HIV) antiretroviral regimens are needed. We evaluated the efficacy and safety of daclatasvir + sofosbuvir (DCV + SOF) for 12 weeks by antiretroviral (ARV) regimen in HIV-HCV-coinfected patients. In the randomized, open-label ALLY-2 study, HIV-HCV-coinfected patients received 8 or 12 weeks of once-daily DCV 60 mg (dose-adjusted as-necessary for concomitant ARVs) + SOF 400 mg. Results were stratified by ARV class for the 151 patients who received 12 weeks of DCV + SOF. Fifty-one patients were HCV treatment experienced, 100 were treatment naive, 89% male and 33% black. HCV genotypes were: genotype 1a (GT1a; 69%), GT1b (15%), GT2 (8%), GT3 (6%), and GT4 (2%). Sustained virologic response 12 weeks post-treatment (SVR12) was 97% and was similar across ARV regimens (P = .774): protease inhibitor-based, 97% (95% confidence interval [CI], 90%-99.7%); nonnucleoside reverse transcriptase inhibitor-based, 100% (95% CI, 91%-100%); and integrase inhibitor based, 95% (95% CI, 83%-99.4%). SVR12 among patients receiving either tenofovir disoproxil fumarate or abacavir as part of their antiretroviral therapy regimen was 98% (95% CI, 93%-99.5%) and 100% (95% CI, 85%-100%), respectively. Age, gender, race, cirrhosis, HCV treatment history, GT , and baseline HCV RNA did not affect SVR12. No discontinuations were attributed to treatment-related adverse events. DCV + SOF x12 weeks is a highly efficacious, all-oral, pan-GT HCV treatment for HIV-HCV coinfected patients across a broad range of ARV regimens. NCT02032888. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  18. HCV core-antigen assay as an alternative to HCV RNA quantification: A correlation study for the assessment of HCV viremia.

    Science.gov (United States)

    Alonso, Roberto; Pérez-García, Felipe; López-Roa, Paula; Alcalá, Luis; Rodeño, Pilar; Bouza, Emilio

    2017-02-25

    Detection of hepatitis C virus (HCV) RNA and the HCV core antigen assay (HCV-Ag) are reliable techniques for the diagnosis of active and chronic HCV infection. Our aim was to evaluate the HCV-Ag assay as an alternative to quantification of HVC RNA. A comparison was made of the sensitivity and specificity of an HCV-Ag assay (204 serum samples) with those of a PCR assay, and the correlation between the two techniques was determined. The sensitivity and specificity of HCV-Ag was 76.6% and 100%, respectively. Both assays were extremely well correlated (Pearson coefficient=0.951). The formula (LogCV=1.15*LogAg+2.26) was obtained to calculate the viral load by PCR from HCV-Ag values. HCV-Ag was unable to detect viral loads below 5000IU/mL. Although the HCV-Ag assay was less sensitive than the PCR assay, the correlation between both assays was excellent. HCV-Ag can be useful as a first step in the diagnosis of acute or chronic HCV infection and in emergency situations. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  19. Development and evaluation of a MAb based competitive-ELISA using helicase domain of NS3 protein for sero-diagnosis of bovine viral diarrhea in cattle and buffaloes.

    Science.gov (United States)

    Bhatia, S; Sood, Richa; Mishra, N; Pattnaik, B; Pradhan, H K

    2008-08-01

    The aim of this study was to develop a competitive inhibition ELISA (CI-ELISA) for detection of antibodies to bovine viral diarrhea virus (BVDV) using the helicase domain of NS3 (non-structural) protein and monoclonal antibody (MAb) against it and to estimate its sensitivity and specificity using two commercial ELISA kits as independent references. The 45-kDa helicase domain of NS3 protein of BVDV was expressed in Escherichia coli and 18MAbs were developed against it. MAb-11G8 was selected for use in CI-ELISA on the basis of maximum inhibition (90%) obtained with BVDV type 1 infected calf serum. Based on the distribution of percent inhibition of known negative sera (n=166), a cut-off value was set at 40% inhibition. In testing 914 field serum samples of cattle (810) and buffaloes (104), the CI-ELISA showed a relative specificity of 95.75% and 97.38% and sensitivity of 96% and 94.43% with Ingenesa kit and Institut Pourquier kit, respectively. This study proved that the use of helicase domain of NS3 (45-kDa) is equally good as the whole NS3 protein (80-kDa) used in commercial kits for detection of BVDV antibodies in cattle and buffaloes.

  20. The neuropsychiatric aspect of the HCV infection.

    Science.gov (United States)

    Więdłocha, Magdalena; Marcinowicz, Piotr; Sokalla, Dorota; Stańczykiewicz, Bartłomiej

    2017-01-01

    HCV infection is significantly more prevalent in the population of psychiatric patients, drug addicts and people tending to undertake risky sexual behaviors than in the general population. This article presents a spectrum of psychopathological symptoms and psychological dysfunctions, an outline of current theories on the neuropathology and psychiatric aspects of HCV infection treatment. The unspecific character of the psychopathological symptoms in the HCV infection makes the process of thorough diagnostics and adequate treatment difficult, thus the specific and characteristic features have been emphasized. The aim of this review is to shed light not only on the basic information concerning CNS pathology but also on the conclusions emerging from the studies of different authors, of various methodology, in diverse study groups and also to investigate current topics of research. The results of neuroimaging studies have been presented as well. Attention has also been dedicated separately to specific issues, like psychiatric aspects of co-infection with HCV and HIV viruses, the chronic fatigue in the course of HCV infection, the influence of substance use disorders and difficulties encountered during treatment with interferon. Undiagnosed psychiatric disorders, not only inevitably decrease the already rather low quality of life but also cause non-adherence with recommendations and medications regimes, contributing to a worse treatment outcome. Finally, the above disorders, when left untreated, result in higher rates of risk-taking behaviors among the infected, thus imposing a danger not only to patients themselves but also to the healthy population.

  1. Fluorimetric and HPLC-based dengue virus protease assays using a FRET substrate.

    Science.gov (United States)

    Nitsche, Christoph; Klein, Christian D

    2013-01-01

    The number of dengue virus infections is increasing and the dengue NS2B-NS3 protease is considered a promising target for the development of antiviral therapies. Therefore, reliable and fast screening systems are needed for the discovery of new lead structures. In this chapter, we describe two dengue virus protease assays based on an internally quenched, high-affinity Förster resonance energy transfer (FRET) substrate (Km = 105 μM). A fluorimetric assay using a microtiter fluorescence plate reader can be used for high-throughput screening of a large number of compounds. Alternatively, an HPLC-based assay with fluorescence detection can be applied to confirm the compound hits and to avoid false-positive results that may arise due to the inner filter effect of some compounds.

  2. Detection of HCV core antigen and its diagnostic significance

    Directory of Open Access Journals (Sweden)

    YANG Jie

    2013-02-01

    Full Text Available ObjectiveTo compare the abilities of the hepatitis C virus (HCV core antigen (cAg test and the HCV RNA assay for confirming anti-HCV presence in order to determine the clinical utility of the HCV-cAg as an alternative or confirmatory diagnostic tool. MethodsSerum samples collected from 158 patients diagnosed with HCV infection were subjected to the enzyme-linked immunosorbent assay-based HCV-cAg test. The optical density (OD measured values were used to calculate the ratio of specimen absorbance to the cutoff value (S/CO. Simultaneously, the serum samples were subjected to PCR-based nucleic acid amplification quantitative fluorescence detection of HCV RNA. ResultsNone of the serum samples had a S/CO value <1 for the HCV-cAg test (100% negative, but all of the samples had a S/CO value >5 (100% positive. The HCV-cAg test sensitivity was 87.05%, specificity was 76.67%, positive predictive value was 9653%, and negative predictive value was 44.23%. As the S/CO value gradually increased, the significantly higher positive coincident rate of the HCV RNA test decreased. The HCV RNA negative coincident rate was significantly higher than that of the HCV-cAg test. HCV-cAg S/CO values between 1 and 2 corresponded to an HCV RNA values between 1.0×103 copies/ml and 1.0×104 copies/ml. The highest S/CO value obtained was 1.992. ConclusionThe HCV-cAg test is comparable to the HCV RNA assay for diagnosing HCV infection.

  3. New Insights in Recurrent HCV Infection after Liver Transplantation

    Directory of Open Access Journals (Sweden)

    Shih-Hsien Hsu

    2013-01-01

    Full Text Available Hepatitis C virus (HCV is a small-enveloped RNA virus belonging to the Flaviviridae family. Since first identified in 1989, HCV has been estimated to infect 170 million people worldwide. Mostly chronic hepatitis C virus has a uniform natural history, from liver cirrhosis to the development of hepatocellular carcinoma. The current therapy for HCV infection consists of a combination of Pegylated interferon and ribavirin. On the other hand, HCV-related liver disease is also the leading indication for liver transplantation. However, posttransplant HCV re-infection of the graft has been reported to be universal. Furthermore, the graft after HCV re-infection often results in accelerated progression to liver failure. In addition, treatment of recurrent HCV infection after liver transplantation is often compromised by enhanced adverse effects and limited efficacy of interferon-based therapies. Taken together, poor outcome after HCV re-infection, regardless of grafts or recipients, poses a major issue for the hepatologists and transplant surgeons. The aim of this paper is to review several specific aspects regarding HCV re-infection after transplant: risk factors, current therapeutics for HCV in different stages of liver transplantation, cellular function of HCV proteins, and molecular mechanisms of HCV entry. Hopefully, this paper will inspire new strategies and novel inhibitors against recurrent HCV infection after liver transplantation and greatly improve its overall outcome.

  4. Antiviral activity of telaprevir (VX-950) and peginterferon alfa-2a in patients with hepatitis C

    NARCIS (Netherlands)

    Forestier, Nicole; Reesink, Hendrik W.; Weegink, Christine J.; McNair, Lindsay; Kieffer, Tara L.; Chu, Hui-May; Purdy, Susan; Jansen, Peter L. M.; Zeuzem, Stefan

    2007-01-01

    Telaprevir (VX-950), an inhibitor of the hepatitis C virus (HCV) NS3/4A protease, substantially decreased plasma HCV RNA levels in a prior clinical study. The present study evaluated viral kinetics and safety during dosing with telaprevir alone and in combination with peginterferon alfa-2a for 14

  5. Immunological HCV-Associated Thrombocytopenia: Short Review

    Directory of Open Access Journals (Sweden)

    Dimitrios Dimitroulis

    2012-01-01

    Full Text Available Infection with Hepatitis C virus (HCV is affecting about 3% of the world's population, leading to liver damage, end-stage liver disease, and development of hepatocellular carcinoma, being thus the first indication for liver transplantation in the USA. Apart from the cirrhotic-liver-derived clinical signs and symptoms several conditions with immunological origin can also arise, such as, glomerulonephritis, pulmonary fibrosis, and thrombocytopenia. HCV-related autoimmune thrombocytopenia shows specific pathogenetic characteristics as well as symptoms and signs that differ in severity and frequency from symptoms in patients that are not HCV infected. Aim of this short paper is to estimate the epidemiological characteristics of the disease, to investigate the pathogenesis and clinical manifestation, and to propose treatment strategies according to the pertinent literature.

  6. HCV genetic heterogeneity and its host genetics

    Directory of Open Access Journals (Sweden)

    NIE Yonghong

    2013-10-01

    Full Text Available Hepatitis C represents a major worldwide public health problem. Studies have shown that both genetic diversity of hepatitis C virus (HCV and genetic polymorphisms of IL-28B, ITPA, and IP-10 in the host are implicated in the progression of hepatitis C, treatment response, and adverse effects. The research advances in the molecular epidemiology and clinical and therapeutic interventions of HCV genetic heterogeneity and single nucleotide polymorphisms in its host are reviewed. It is suggested that there is a pressing need for reliable data on the molecular epidemiology of HCV and its host, which will assist in the decision making of public health issues and reduce the morbidity and mortality of hepatitis C worldwide.

  7. Prevalence of mixed hepatitis C virus (HCV genotypes among recently diagnosed dialysis patients with HCV infection

    Directory of Open Access Journals (Sweden)

    Mohammed A Al Balwi

    2011-01-01

    Full Text Available Hepatitis C virus (HCV infection is considered a major health problem recognized globally. HCV is a major cause of chronic liver disease that may lead to cirrhosis and hepatocellular carcinoma. The aim of this study was to investigate the prevalence of multiple (mixed HCV genotypes in Saudi patients recently diagnosed with HCV infection and their association with various clinical risk factors. We examined a total of 1,292 newly diagnosed HCV-positive cases between January 2006 and July 2009 at the Molecular Pathology Laboratory, King Abdulaziz Medical City, Riyadh. The clinical and laboratory data of the study patients were collected. The HCV-RNA viral load and its genotyping were carried out with RT-PCR technology to assist in the follow-up and management of HCV-infected patients undergoing antiviral therapy. Twenty-two patients (1.7% were found to have mixed HCV genotypes; of them, mixed genotypes associated with genotype-4 were seen in 19 patients (86%, mixed genotypes associated with genotype-1 were found in 68.4%, with genotype-3 in 26.3% and with genotype-2 in 5.3%. Additionally, mixed genotypes associated with genotype-1 were seen in three cases (13.6%; they were associated with genotype-2 in two (66.7% and with genotype-5 in one patient (33.3%. In conclusion, the prevalence rate of mixed HCV genotypes in the cohort of the newly infected Saudi patients was 1.7%, with genotype-4 being the most frequent genotype encountered.

  8. HCV viremia is associated with drug use in young HIV-1 and HCV coinfected pregnant and non-pregnant women*

    Science.gov (United States)

    Nikolopoulou, Georgia B.; Nowicki, Marek J.; Du, Wenbo; Homans, James; Stek, Alice; Kramer, Francoise; Kovacs, Andrea

    2011-01-01

    Aims Vertical transmission of HCV is increased among HIV-1/HCV coinfected women and is related to HCV viral load. In this study we assessed clinical and demographic factors associated with HCV viremia in a cohort of young pregnant and non-pregnant mothers coinfected with HIV-1. Design A cross-sectional clinic-based study nested within a prospective cohort study. Methods From 1988 to 2000, HIV-1 + pregnant and non-pregnant women with children followed in a large maternal, child and adolescent HIV-1 clinic were evaluated for HCV infection using EIA 3.0. HCV RNA levels were determined for HCV antibody + women using polymerase chain reaction. Demographic and clinical characteristics between HCV-RNA(+) and HCV-RNA(−) women and between pregnant and non-pregnant HIV-1/HCV coinfected women were compared using univariate and multivariate analyses. Findings Among 359 HIV-1(+) women, 84 (23%) were HCV-ab + and 49/84 (58%) had detectable HCV-RNA in plasma. Median age was 31. CD4 counts, HIV-1 RNA levels and demographic characteristics were similar for viremic and non-viremic women and pregnant and non-pregnant women. However, viremic women were more likely to report a history of (88% versus 43%; P < 0.001) or active injection drug use (AIDU) (83% versus 29%; P < 0.001). Logistic regression analysis showed that HCV viremia was associated significantly with AIDU (adjusted OR: 15.17; 95% CI: 3.56, 64.56) after adjusting for age, race, number of sexual partners, pregnancy status, CD4 counts and HIV-1 viral load. Conclusion In this cohort of young HIV-1 and HCV coinfected women, HCV viremia was associated strongly with active injection drug use, perhaps due to reinfection or reactivation of HCV. Thus, careful evaluation for HCV infection and counseling related to drug use may be necessary. PMID:15847620

  9. HCV tumor promoting effect is dependent on host genetic background.

    Directory of Open Access Journals (Sweden)

    Naama Klopstock

    Full Text Available BACKGROUND: The hepatitis C virus (HCV is one of the major risk factors for the development of hepatocellular carcinoma (HCC. Nevertheless, transgenic mice which express the whole HCV polyprotein (HCV-Tg do not develop HCC. Whereas chronic HCV infection causes inflammation in patients, in HCV-Tg mice, the host immune reaction against viral proteins is lacking. We aimed to test the role of HCV proteins in HCC development on the background of chronic inflammation in vivo. METHODOLOGY/PRINCIPAL FINDINGS: We crossed HCV-Tg mice that do not develop HCC with the Mdr2-knockout (Mdr2-KO mice which develop inflammation-associated HCC, to generate Mdr2-KO/HCV-Tg mice. We studied the effect of the HCV transgene on tumor incidence, hepatocyte mitosis and apoptosis, and investigated the potential contributing factors for the generated phenotype by gene expression and protein analyses. The Mdr2-KO/HCV-Tg females from the N2 generation of this breeding (having 75% of the FVB/N genome and 25% of the C57BL/6 genome produced significantly larger tumors in comparison with Mdr2-KO mice. In parallel, the Mdr2-KO/HCV-Tg females had an enhanced inflammatory gene expression signature. However, in the N7 generation (having 99.2% of the FVB/N genome and 0.8% of the C57BL/6 genome there was no difference in tumor development between Mdr2-KO/HCV-Tg and Mdr2-KO animals of both sexes. The HCV transgene was similarly expressed in the livers of Mdr2-KO/HCV-Tg females of both generations, as revealed by detection of the HCV transcript and the core protein. CONCLUSION: These findings suggest that the HCV transgene accelerated inflammation-associated hepatocarcinogenesis in a host genetic background-dependent manner.

  10. Packaging of HCV-RNA into lentiviral vector

    Energy Technology Data Exchange (ETDEWEB)

    Caval, Vincent [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Piver, Eric [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Service de Biochimie et Biologie Moleculaire, CHRU de Tours (France); Ivanyi-Nagy, Roland; Darlix, Jean-Luc [LaboRetro, ENS-Lyon INSERM, U758, 46 Allee d' Italie, 69364 Lyon (France); Pages, Jean-Christophe, E-mail: jean-christophe.pages@univ-tours.fr [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Service de Biochimie et Biologie Moleculaire, CHRU de Tours (France)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Description of HCV-RNA Core-D1 interactions. Black-Right-Pointing-Pointer In vivo evaluation of the packaging of HCV genome. Black-Right-Pointing-Pointer Determination of the role of the three basic sub-domains of D1. Black-Right-Pointing-Pointer Heterologous system involving HIV-1 vector particles to mobilise HCV genome. Black-Right-Pointing-Pointer Full length mobilisation of HCV genome and HCV-receptor-independent entry. -- Abstract: The advent of infectious molecular clones of Hepatitis C virus (HCV) has unlocked the understanding of HCV life cycle. However, packaging of the genomic RNA, which is crucial to generate infectious viral particles, remains poorly understood. Molecular interactions of the domain 1 (D1) of HCV Core protein and HCV RNA have been described in vitro. Since compaction of genetic information within HCV genome has hampered conventional mutational approach to study packaging in vivo, we developed a novel heterologous system to evaluate the interactions between HCV RNA and Core D1. For this, we took advantage of the recruitment of Vpr fusion-proteins into HIV-1 particles. By fusing HCV Core D1 to Vpr we were able to package and transfer a HCV subgenomic replicon into a HIV-1 based lentiviral vector. We next examined how deletion mutants of basic sub-domains of Core D1 influenced HCV RNA recruitment. The results emphasized the crucial role of the first and third basic regions of D1 in packaging. Interestingly, the system described here allowed us to mobilise full-length JFH1 genome in CD81 defective cells, which are normally refractory to HCV infection. This finding paves the way to an evaluation of the replication capability of HCV in various cell types.

  11. Correlation between alanine aminotransferase level, HCV-RNA titer ...

    African Journals Online (AJOL)

    Quantitative HCV-RNA level measurement, HCV genotyping, and abdominal ultrasonography were investigated in all patients. Liver biopsy was done for 80 patients and the remaining 58 patients were examined using Fibroscan. Highly significant higher percentage of cases with high level of HCV viremia was found among ...

  12. Prevalence of HCV Infections Among Hemodialysis Patients in Al ...

    African Journals Online (AJOL)

    1527 patients (11%) who were HCV free at the start of the study. By the end of the study, a total of 42.2% were found to be anti-HCV reactive. Conclusion: The study demonstrated high prevalence of anti-HCV in HD units in Al Gharbiyah Governorate. Similar studies must be conducted in all Egyptian governorates' HD units ...

  13. HCV RNA in peripheral blood mononuclear cells (PBMCs) as a ...

    African Journals Online (AJOL)

    Abdel Fatah Fahmy Hanno

    2013-06-27

    Jun 27, 2013 ... Objectives: To study hepatitis virus C (HCV) RNA in peripheral blood mononuclear cells. (PBMCs) of patients with chronic HCV infection, and explore the relationship between the HCV. RNA in the PBMCs and response to interferon (IFN) therapy. Methods: Twenty-five patients with chronic viral hepatitis C ...

  14. Successful Retreatment of Chronic HCV Genotype-1 Infection With Ledipasvir and Sofosbuvir After Initial Short Course Therapy With Direct-Acting Antiviral Regimens.

    Science.gov (United States)

    Wilson, Eleanor M; Kattakuzhy, Sarah; Sidharthan, Sreetha; Sims, Zayani; Tang, Lydia; McLaughlin, Mary; Price, Angie; Nelson, Amy; Silk, Rachel; Gross, Chloe; Akoth, Elizabeth; Mo, Hongmei; Subramanian, G Mani; Pang, Phillip S; McHutchison, John G; Osinusi, Anu; Masur, Henry; Kohli, Anita; Kottilil, Shyam

    2016-02-01

    The optimal retreatment strategy for chronic hepatitis C virus (HCV) patients who fail directly-acting antiviral agent (DAA)-based treatment is unknown. In this study, we assessed the efficacy and safety of ledipasvir (LDV) and sofosbuvir (SOF) for 12 weeks in HCV genotype-1 (GT-1) patients who failed LDV/SOF-containing therapy. In this single-center, open-label, phase 2a trial, 34 participants with HCV (GT-1) and early-stage liver fibrosis who previously failed 4-6 weeks of LDV/SOF with GS-9669 and/or GS-9451 received LDV/SOF for 12 weeks. The primary endpoint was HCV viral load below the lower limit of quantification 12 weeks after completion of therapy (sustained virological response [SVR]12). Deep sequencing of the NS3, NS5A, and NS5B regions were performed at baseline, at initial relapse, prior to retreatment, and at second relapse with Illumina next-generation sequencing technology. Thirty-two of 34 enrolled participants completed therapy. Two patients withdrew after day 0. Participants were predominantly male and black, with median baseline HCV viral load of 1.3 × 10(6) IU/mL and Metavir fibrosis stage 1 and genotype-1a. Median time from relapse to retreatment was 22 weeks. Prior to retreatment, 29 patients (85%) had NS5A-resistant variants. The SVR12 rate was 91% (31/34; intention to treat, ITT) after retreatment. One patient relapsed. In patients who previously failed short-course combination DAA therapy, we demonstrate a high SVR rate in response to 12 weeks of LDV/SOF, even for patients with NS5A resistance-associated variants. NCT01805882. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  15. HCV and Oxidative Stress in the Liver

    Directory of Open Access Journals (Sweden)

    Sergey N. Kochetkov

    2013-01-01

    Full Text Available Hepatitis C virus (HCV is the etiological agent accounting for chronic liver disease in approximately 2–3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies.

  16. HCV and Oxidative Stress in the Liver

    Science.gov (United States)

    Ivanov, Alexander V.; Bartosch, Birke; Smirnova, Olga A.; Isaguliants, Maria G.; Kochetkov, Sergey N.

    2013-01-01

    Hepatitis C virus (HCV) is the etiological agent accounting for chronic liver disease in approximately 2–3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS) in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies. PMID:23358390

  17. Indications for treatment in chronic HCV infection.

    Science.gov (United States)

    Dávalos Moscol, Milagros

    2010-01-01

    HCV Infection is a global burden disease and it is related to the development of progressive liver fibrosis, cirrhosis and hepatocellular carcinoma. At least 80% of the persons that have an acute infection evolve to chronicity. This event affects the patient and their contacts for the risk of acquiring the infection. Once chronic HCV is present some factors accelerate progression: older age, obesity, alcohol consumption, etc. Severity of fibrosis is one of the most important factors to be analyzed before deciding to treat a patient. Pegylated interferon and ribavirin is the .standard of care. for this disease, however, it has many side effects, some of them life threatening. That is the reason why this treatment must be indicated in the right moment in the right patient. A complete medical evaluation must be done previously to initiate treatment. Other concurrent problems must be ruled out or treated. Decompensated cirrhosis, autoimmune diseases or other uncontrolled disease are contraindication to HCV treatment. Previous failure to treatment for HCV must be analyzed to identify the reasons for that event and consider retreatment. Cryoglobulinemia and membranoproliferative glomerulonephritis are indications for treatment independent from the severity of liver disease.

  18. Correlates of HCV seropositivity among familial contacts of HCV positive patients

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    Matera Antonio

    2006-09-01

    Full Text Available Abstract Background Determinants of intrafamilial HCV transmission are still being debated. The aim of this study is to investigate the correlates of HCV seropositivity among familial contacts of HCV positive patients in Italy. Methods A cross-sectional study was conducted with 175 HCV positive patients (index cases, recruited from Policlinico Gemelli in Rome as well as other hospitals in Central Italy between 1995 and 2000 (40% female, mean age 57 ± 15.2 years, and 259 familial contacts. Differences in proportions of qualitative variables were tested with non-parametric tests (χ2, Yates correction, Fisher exact test, and a p value Results Seropositivity for HCV was found in 8.9% of the contacts. From the univariate analysis, risk factors significantly associated to HCV positivity in the contacts were: intravenous drug addiction (p = 0.004 and intercourse with drug addicts (p = 0.005. The only variables associated significantly and independently to HCV seropositivity in patients' contacts were intercourse with drug addicts (OR = 19.28; 95% CI: 2.01 – 184.94, the retirement status from work (OR = 3.76; 95% CI: 1.17 – 11.98, the time of the relationship (OR = 1.06; 95% CI: 1.00 – 1.11 and tattoos (OR = 7.68; 95% CI: 1.00 – 60.20. Conclusion The present study confirms that having intercourse with a drug addict is the most significant risk factor for intrafamilial HCV transmission. The association with retirement status from work could be related to both a long-term relationship with an index case and past exposure to common risk factors.

  19. Hepatitis C virus (HCV) RNA profiles among chronic HIV/HCV-coinfected individuals in ESPRIT; spontaneous HCV RNA clearance observed in nine individuals.

    Science.gov (United States)

    Grint, D; Tedaldi, E; Peters, L; Mocroft, A; Edlin, B; Gallien, S; Klinker, H; Boesecke, C; Kokordelis, P; Rockstroh, J K

    2017-07-01

    Studies have shown that hepatitis C virus (HCV) RNA levels remain stable over time in HIV/HCV-coinfected individuals taking combination antiretroviral therapy (cART), while spontaneous clearance of HCV RNA during the persistent infection phase has been documented only rarely among those with the CC interleukin (IL)-28B genotype. This study describes HCV RNA profiles and factors associated with changes over time in HCV RNA levels in the ESPRIT study. HIV/HCV-coinfected individuals positive for HCV RNA were included in the study. Follow-up was counted from the first HCV RNA positive test and censored at the initiation of interferon-based treatment. HCV RNA and IL-28B measurements were performed in the same reference laboratory. Random effects mixed models were used to analyse changes over time in HCV RNA. A total of 312 ESPRIT patients were included in the study (151 in the arm receiving subcutaneous recombinant IL-2 and 161 in the control arm). Most of the patients were white (89%) and male (76%), and they had a median of 5 HCV RNA measurements per person [interquartile range (IQR) 3-6; range 1-9]. Median follow-up was 5 years (IQR: 2-6 years). At baseline, 96% of patients were taking cART and 93% had undetectable HIV RNA. Mean HCV RNA levels decreased by 13% per year over the study period [95% confidence interval (CI) 8-18%; P < 0.0001]. Baseline HCV RNA levels and the change over time in HCV RNA did not differ by randomization arm (P = 0.16 and P = 0.56, respectively). Nine individuals spontaneously cleared HCV RNA during follow-up [IL-28B genotypes: CC, five patients (56%); CT, four patients (44%)]. HCV RNA levels decreased over time in this population with well-controlled HIV infection. Spontaneous clearance of HCV RNA was documented in five individuals with IL-28B genotype CC and four with the CT genotype. © 2016 British HIV Association.

  20. Cleavage of Dicer protein by I7 protease during vaccinia virus infection.

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    Jhih-Si Chen

    Full Text Available Dicer is the key component in the miRNA pathway. Degradation of Dicer protein is facilitated during vaccinia virus (VV infection. A C-terminal cleaved product of Dicer protein was detected in the presence of MG132 during VV infection. Thus, it is possible that Dicer protein is cleaved by a viral protease followed by proteasome degradation of the cleaved product. There is a potential I7 protease cleavage site in the C-terminus of Dicer protein. Indeed, reduction of Dicer protein was detected when Dicer was co-expressed with I7 protease but not with an I7 protease mutant protein lack of the protease activity. Mutation of the potential I7 cleavage site in the C-terminus of Dicer protein resisted its degradation during VV infection. Furthermore, Dicer protein was reduced dramatically by recombinant VV vI7Li after the induction of I7 protease. If VV could facilitate the degradation of Dicer protein, the process of miRNA should be affected by VV infection. Indeed, accumulation of precursor miR122 was detected after VV infection or I7 protease expression. Reduction of miR122 would result in the suppression of HCV sub-genomic RNA replication, and, in turn, the amount of viral proteins. As expected, significant reduction of HCVNS5A protein was detected after VV infection and I7 protease expression. Therefore, our results suggest that VV could cleave Dicer protein through I7 protease to facilitate Dicer degradation, and in turn, suppress the processing of miRNAs. Effect of Dicer protein on VV replication was also studied. Exogenous expression of Dicer protein suppresses VV replication slightly while knockdown of Dicer protein does not affect VV replication significantly.

  1. Seroprevalence of HCV among Cairo University students in Egypt.

    Science.gov (United States)

    Esmat, Gamal; Raziky, Maissa El; Nabeel, Mohammed M; Maher, Rabab; Zakaria, Zeinab

    2016-08-01

    Hepatitis C virus (HCV) is highly prevalent in Egypt. This work aimed at determining the seroprevalence of HCV among Cairo University students. The present study included 3,000 students from Cairo University, Egypt. Blood sample was obtained from each participant to be tested for HCV seromarker. HCV RNA detection by polymerase chain reaction (PCR) was carried out for those with positive anti-HCV. Overall prevalence rate of HCV antibody (anti-HCV) was 4.6%. It showed that the prevalence was relatively higher among females (86/1660; 5.2%) while males (51/1340; 3.8%) with no significant difference. PCR for HCV RNA was detected in 31.4% of the HCV antibody positive subjects (43/137). Which showed statistical significant difference between males (29/51) and females (14/86) at P = 0.001. Despite the prevalence rate reported in the present study was similar to anti-HCV prevalence among persons in the same age group, confirmed that HCV infection is detected among Cairo University students. J. Med. Virol. 88:1384-1387, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Secreted proteases from dermatophytes.

    Science.gov (United States)

    Monod, Michel

    2008-01-01

    Dermatophytes are highly specialized pathogenic fungi that exclusively infect the stratum corneum, nails or hair, and it is evident that secreted proteolytic activity is important for their virulence. Endo- and exoproteases-secreted by dermatophytes are similar to those of species of the genus Aspergillus. However, in contrast to Aspergillus spp., dermatophyte-secreted endoproteases are multiple and are members of two large protein families, the subtilisins (serine proteases) and the fungalysins (metalloproteases). In addition, dermatophytes excrete sulphite as a reducing agent. In the presence of sulphite, disulphide bounds of the keratin substrate are directly cleaved to cysteine and S-sulphocysteine, and reduced proteins become accessible for further digestion by various endo- and exoproteases secreted by the fungi. Sulphitolysis is likely to be an essential step in the digestion of compact keratinized tissues which precedes the action of all proteases.

  3. Multiclass HCV resistance to direct-acting antiviral failure in real-life patients advocates for tailored second-line therapies.

    Science.gov (United States)

    Di Maio, Velia C; Cento, Valeria; Lenci, Ilaria; Aragri, Marianna; Rossi, Piera; Barbaliscia, Silvia; Melis, Michela; Verucchi, Gabriella; Magni, Carlo F; Teti, Elisabetta; Bertoli, Ada; Antonucci, FrancescoPaolo; Bellocchi, Maria C; Micheli, Valeria; Masetti, Chiara; Landonio, Simona; Francioso, Simona; Santopaolo, Francesco; Pellicelli, Adriano M; Calvaruso, Vincenza; Gianserra, Laura; Siciliano, Massimo; Romagnoli, Dante; Cozzolongo, Raffaele; Grieco, Antonio; Vecchiet, Jacopo; Morisco, Filomena; Merli, Manuela; Brancaccio, Giuseppina; Di Biagio, Antonio; Loggi, Elisabetta; Mastroianni, Claudio M; Pace Palitti, Valeria; Tarquini, Pierluigi; Puoti, Massimo; Taliani, Gloria; Sarmati, Loredana; Picciotto, Antonino; Vullo, Vincenzo; Caporaso, Nicola; Paoloni, Maurizio; Pasquazzi, Caterina; Rizzardini, Giuliano; Parruti, Giustino; Craxì, Antonio; Babudieri, Sergio; Andreoni, Massimo; Angelico, Mario; Perno, Carlo F; Ceccherini-Silberstein, Francesca

    2017-04-01

    Despite the excellent efficacy of direct-acting antivirals (DAA) reported in clinical trials, virological failures can occur, often associated with the development of resistance-associated substitutions (RASs). This study aimed to characterize the presence of clinically relevant RASs to all classes in real-life DAA failures. Of the 200 virological failures that were analyzed in 197 DAA-treated patients, 89 with pegylated-interferon+ribavirin (PegIFN+RBV) and 111 without (HCV-1a/1b/1g/2/3/4=58/83/1/6/24/25; 56.8% treatment experienced; 65.5% cirrhotic) were observed. Sanger sequencing of NS3/NS5A/NS5B was performed by home-made protocols, at failure (N=200) and whenever possible at baseline (N=70). The majority of the virological failures were relapsers (57.0%), 22.5% breakthroughs, 20.5% non-responders. RAS prevalence varied according to IFN/RBV use, DAA class, failure type and HCV genotype/subtype. It was 73.0% in IFN group vs 49.5% in IFN free, with the highest prevalence of NS5A-RASs (96.1%), compared to NS3-RASs (75.9% with IFN, 70.5% without) and NS5B-RASs (66.6% with IFN, 20.4% without, in sofosbuvir failures). In the IFN-free group, RASs were higher in breakthrough/non-responders than in relapsers (90.5% vs 40.0%, Presistance, including 11/11 NS3+NS5A failures. Furthermore, 20.0% of patients had baseline-RASs, which were always confirmed at failure. In our failure setting, RAS prevalence was remarkably high in all genes, with a partial exception for NS5B, whose limited resistance is still higher than previously reported. This multiclass resistance advocates for HCV resistance testing at failure, in all three genes for the best second-line therapeutic tailoring. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. PML tumor suppressor protein is required for HCV production

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, Misao [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Research Fellow of the Japan Society for the Promotion of Science (Japan); Center for AIDS Research, Kumamoto University, Kumamoto 860-0811 (Japan); Ariumi, Yasuo, E-mail: ariumi@kumamoto-u.ac.jp [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Center for AIDS Research, Kumamoto University, Kumamoto 860-0811 (Japan); Hijikata, Makoto [Department of Viral Oncology, Institute for Virus Research, Kyoto University, Kyoto 606-8507 (Japan); Ikeda, Masanori; Dansako, Hiromichi [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Wakita, Takaji [Department of Virology II, National Institute of Infectious Diseases, Tokyo 162-8640 (Japan); Shimotohno, Kunitada [Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Ichikawa, Chiba 272-8516 (Japan); Kato, Nobuyuki [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer PML tumor suppressor protein is required for HCV production. Black-Right-Pointing-Pointer PML is dispensable for HCV RNA replication. Black-Right-Pointing-Pointer HCV could not alter formation of PML-NBs. Black-Right-Pointing-Pointer INI1 and DDX5, PML-related proteins, are involved in HCV life cycle. -- Abstract: PML tumor suppressor protein, which forms discrete nuclear structures termed PML-nuclear bodies, has been associated with several cellular functions, including cell proliferation, apoptosis and antiviral defense. Recently, it was reported that the HCV core protein colocalizes with PML in PML-NBs and abrogates the PML function through interaction with PML. However, role(s) of PML in HCV life cycle is unknown. To test whether or not PML affects HCV life cycle, we examined the level of secreted HCV core and the infectivity of HCV in the culture supernatants as well as the level of HCV RNA in HuH-7-derived RSc cells, in which HCV-JFH1 can infect and efficiently replicate, stably expressing short hairpin RNA targeted to PML. In this context, the level of secreted HCV core and the infectivity in the supernatants from PML knockdown cells was remarkably reduced, whereas the level of HCV RNA in the PML knockdown cells was not significantly affected in spite of very effective knockdown of PML. In fact, we showed that PML is unrelated to HCV RNA replication using the subgenomic HCV-JFH1 replicon RNA, JRN/3-5B. Furthermore, the infectivity of HCV-like particle in the culture supernatants was significantly reduced in PML knockdown JRN/3-5B cells expressing core to NS2 coding region of HCV-JFH1 genome using the trans-packaging system. Finally, we also demonstrated that INI1 and DDX5, the PML-related proteins, are involved in HCV production. Taken together, these findings suggest that PML is required for HCV production.

  5. Prediction of Intraoperative Blood Loss during Total Knee Arthroplasty in HCV+ and HCV- Patients with Hemophilia A.

    Science.gov (United States)

    Shurkhina, E S; Polyanskaya, T Yu; Zorenko, V Yu; Nesterenko, V M

    2017-03-01

    We examined HCV+ and HCV- hemophilia A patients with knee arthropathy and hematocrit above 38.5%. The mean density of erythrocytes was studied by the phthalate method, intraoperative blood loss was assessed gravimetrically. The volume of blood loss in HCV+ patients with manifest adhesive process and chronic synovitis varied from 300 to 1900 ml, in patients with moderate adhesive process from 400 to 1500 ml. The volume of blood loss in HCV- patients was 300-800 ml. A positive correlation between the blood loss volume and mean density of erythrocytes was detected. Blood loss >1000 ml during total knee arthroplasty can be expected in patients with hemophilia A with HCV and high mean density of erythrocytes. Blood loss >1000 ml is unlikely in HCV- and HCV+ patients with the mean density of erythrocytes not surpassing the normal values.

  6. Nucleic Acid Aptamers Against Proteases

    DEFF Research Database (Denmark)

    Dupont, D M; Andersen, L M; Bøtkjær, Kenneth Alrø

    2011-01-01

    Proteases are potential or realized therapeutic targets in a wide variety of pathological conditions. Moreover, proteases are classical subjects for studies of enzymatic and regulatory mechanisms. We here review the literature on nucleic acid aptamers selected with proteases as targets. Designing...... small molecule protease inhibitors of sufficient specificity has proved a daunting task. Aptamers seem to represent a promising alternative. In our review, we concentrate on biochemical mechanisms of aptamer selection, proteinaptamer recognition, protease inhibition, and advantages of aptamers...... for pharmacological intervention with pathophysiological functions of proteases. Aptamers can be selected so that they bind their targets highly specifically and with affinities corresponding to K(D) values in the nM range. Aptamers can be selected so that they recognize their targets conformation...

  7. Clp chaperone-proteases: structure and function.

    Science.gov (United States)

    Kress, Wolfgang; Maglica, Zeljka; Weber-Ban, Eilika

    2009-11-01

    Clp proteases are the most widespread energy-dependent proteases in bacteria. Their two-component architecture of protease core and ATPase rings results in an inventory of several Clp protease complexes that often coexist. Here, we present insights into Clp protease function, from their assembly to substrate recruitment and processing, and how this is coupled to the expense of energy.

  8. Complementary role of HCV and HIV in T-cell activation and exhaustion in HIV/HCV coinfection.

    Science.gov (United States)

    Feuth, Thijs; Arends, Joop E; Fransen, Justin H; Nanlohy, Nening M; van Erpecum, Karel J; Siersema, Peter D; Hoepelman, Andy I M; van Baarle, Debbie

    2013-01-01

    To investigate whether T-cell activation and exhaustion is linked to HCV- and HIV disease parameters in HIV/HCV infected individuals, we studied T-cell characteristics in HIV/HCV coinfected patients and controls. 14 HIV/HCV coinfected, 19 HCV monoinfected, 10 HIV monoinfected patients and 15 healthy controls were included in this cross-sectional study. Differences in expression of activation and exhaustion markers (HLA-DR, CD38, PD-1, Tim-3 and Fas) and phenotypic markers on CD4(+) and CD8(+) T-cells were analysed by flow cytometry and were related to HCV disease parameters (HCV-viremia, ALT and liver fibrosis). Frequencies of activated CD4(+) and CD8(+) T-cells were higher in HIV/HCV-coinfected compared to healthy controls and HCV or HIV mono-infected individuals. Coinfected patients also showed high expression of the exhaustion marker PD-1 and death receptor Fas. In contrast, the exhaustion marker Tim-3 was only elevated in HIV-monoinfected patients. T-cell activation and exhaustion were correlated with HCV-RNA, suggesting that viral antigen influences T-cell activation and exhaustion. Interestingly, increased percentages of effector CD8(+) T-cells were found in patients with severe (F3-F4) liver fibrosis compared to those with no to minimal fibrosis (F0-F2). HIV/HCV coinfected patients display a high level of T-cell activation and exhaustion in the peripheral blood. Our data suggest that T-cell activation and exhaustion are influenced by the level of HCV viremia. Furthermore, high percentages of cytotoxic/effector CD8(+) T-cells are associated with liver fibrosis in both HCV monoinfected and HIV/HCV coinfected patients.

  9. Boceprevir in combination with HIV protease inhibitors in patients with advanced fibrosis-altered drug-drug interactions?

    Directory of Open Access Journals (Sweden)

    C Schwarze-Zander

    2012-11-01

    Full Text Available In HIV/HCV co-infected patients improved treatment outcomes have been reported for the HCV protease inhibitors (PIs boceprevir (BOC and telaprevir (TVR, reaching SVR rates of up to 70% in pilot trials. Due to complex drug-drug-interactions triple therapy is substantially limited in HIV/HCV-coinfected individuals. Co-administration of BOC with the commonly available HIV PIs has been reported not only to decrease the level of BOC but also to lead to relevant decreases in the respective HIV PI. Here, we report on two patients who received BOC-containing HCV triple therapy in combination with a HIV PI. Patient 1 was on darunavir 800 mg/ritonavir 100 mg once-daily mono-therapy. Using FibroScan a liver stiffness of 34 kPa suggested liver cirrhosis prior to start of HCV triple therapy. At week 5 of HCV triple therapy darunavir trough concentration was measured in the reference range with 3777 ng/ml (reference trough concentration 2400–4600 ng/ml. HCV-RNA became negative at week 10 and HIV-RNA was below detection limit (<40 copies/ml at all times. Patient 2 was on a simplified FTC qd and fos-amprenavir 700 mg/ritonavir 100 mg bid regimen. Liver disease had also progressed to liver cirrhosis, confirmed in FibroScan, with a liver stiffness of 32 kPa. At week 8 of HCV triple therapy fos-amprenavir trough level was measured in the normal reference range with 1699 ng/ml (reference trough concentration 750–2500 ng/ml. At week 11 HCV-RNA was <12 IU/ml and HIV viral load was below detection limit of <40 copies/ml at all times. Our clinical data suggest that in patients with advanced liver disease possibly drug levels of HIV PIs which are coadministered with BOC may be within the normal range. In order to better understand the true amount of drug interactions between BOC and commonly used HIV PIs in HIV/HCV-coinfected patients with more advanced liver fibrosis, urgently more PK studies are required to make HCV triple therapy accessible for a wider number of

  10. Immune biomarker differences and changes comparing HCV mono-infected, HIV/HCV co-infected, and HCV spontaneously cleared patients.

    Directory of Open Access Journals (Sweden)

    Lauren E Kushner

    Full Text Available Immune biomarkers are implicated in HCV treatment response, fibrosis, and accelerated pathogenesis of comorbidities, though only D-dimer and C-reactive protein have been consistently studied. Few studies have evaluated HIV/HCV co-infection, and little longitudinal data exists describing a broader antiviral cytokine response.Fifty immune biomarkers were analyzed at baseline (BL and HCV end of treatment follow-up(FU time point using the Luminex 50-plex assay in plasma samples from 15 HCV-cleared, 24 HCV mono- and 49 HIV/HCV co-infected patients receiving antiretroviral treatment, who either did or did not receive pegylated-interferon/ribavirin HCV treatment. Biomarker levels were compared among spontaneous clearance patients, mono- and co-infected, untreated and HCV-treated, and sustained virologic responders (SVR and non-responders (NR at BL and FU using nonparametric analyses. A Bonferroni correction, adjusting for tests of 50 biomarkers, was used to reduce Type I error.Compared to HCV patients at BL, HIV/HCV patients had 22 significantly higher and 4 significantly lower biomarker levels, following correction for multiple testing. There were no significantly different BL levels when comparing SVR and NR in mono- or co-infected patients; however, FU levels changed considerably in co-infected patients, with seven becoming significantly higher and eight becoming significantly lower in SVR patients. Longitudinally between BL and FU, 13 markers significantly changed in co-infected SVR patients, while none significantly changed in co-infected NR patients. There were also no significant changes in longitudinal analyses of mono-infected patients achieving SVR or mono-infected and co-infected groups deferring treatment.Clear differences exist in pattern and quantity of plasma immune biomarkers among HCV mono-infected, HIV/HCV co-infected, and HCV-cleared patients; and with SVR in co-infected patients treated for HCV. Though >90% of patients were male and

  11. Large-Scale Structure-Based Prediction and Identification of Novel Protease Substrates Using Computational Protein Design.

    Science.gov (United States)

    Pethe, Manasi A; Rubenstein, Aliza B; Khare, Sagar D

    2017-01-20

    Characterizing the substrate specificity of protease enzymes is critical for illuminating the molecular basis of their diverse and complex roles in a wide array of biological processes. Rapid and accurate prediction of their extended substrate specificity would also aid in the design of custom proteases capable of selectively and controllably cleaving biotechnologically or therapeutically relevant targets. However, current in silico approaches for protease specificity prediction, rely on, and are therefore limited by, machine learning of sequence patterns in known experimental data. Here, we describe a general approach for predicting peptidase substrates de novo using protein structure modeling and biophysical evaluation of enzyme-substrate complexes. We construct atomic resolution models of thousands of candidate substrate-enzyme complexes for each of five model proteases belonging to the four major protease mechanistic classes-serine, cysteine, aspartyl, and metallo-proteases-and develop a discriminatory scoring function using enzyme design modules from Rosetta and AMBER's MMPBSA. We rank putative substrates based on calculated interaction energy with a modeled near-attack conformation of the enzyme active site. We show that the energetic patterns obtained from these simulations can be used to robustly rank and classify known cleaved and uncleaved peptides and that these structural-energetic patterns have greater discriminatory power compared to purely sequence-based statistical inference. Combining sequence and energetic patterns using machine-learning algorithms further improves classification performance, and analysis of structural models provides physical insight into the structural basis for the observed specificities. We further tested the predictive capability of the model by designing and experimentally characterizing the cleavage of four novel substrate motifs for the hepatitis C virus NS3/4 protease using an in vivo assay. The presented structure

  12. CD127 expression, exhaustion status and antigen specific proliferation predict sustained virologic response to IFN in HCV/HIV co-infected individuals.

    Directory of Open Access Journals (Sweden)

    Hassen Kared

    Full Text Available Hepatitis C virus (HCV infection is a major cause of morbidity and mortality in the HIV co-infected population. Interferon-alpha (IFN-α remains a major component of anti-HCV therapy despite its deleterious effects on the immune system. Furthermore, IFN-α was recently shown to diminish the size of the latent HIV reservoir. The objectives of this study were to monitor the impact of IFN-α on T cell phenotype and proliferation of HIV and HCV-specific T cells during IFN therapy, and to identify immune markers that can predict the response to IFN in HICV/HIV co-infected patients. We performed longitudinal analyses of T cell numbers, phenotype and function in co-infected patients undergoing IFN-α therapy with different outcomes including IFN-α non-responders (NR (n = 9 and patients who achieved sustained virologic response (SVR (n = 19. We examined the expression of activation (CD38, HLA-DR, functional (CD127 and exhaustion markers (PD1, Tim-3, CD160 and CD244 on total CD4 and CD8 T cells before, during and after therapy. In addition, we examined the HIV- and HCV-specific proliferative responses against HIV-p24 and HCV-NS3 proteins. Frequencies of CD127+ CD4 T cells were higher in SVR than in NR patients at baseline. An increase in CD127 expression on CD8 T cells was observed after IFN-α therapy in all patients. In addition, CD8 T cells from NR patients expressed a higher exhaustion status at baseline. Finally, SVR patients exhibited higher proliferative response against both HIV and HCV antigens at baseline. Altogether, SVR correlated with higher expression of CD127, lower T cell exhaustion status and better HIV and HCV proliferative responses at baseline. Such factors might be used as non-invasive methods to predict the success of IFN-based therapies in co-infected individuals.

  13. The success of HCV cure: every rose has its thorn.

    Science.gov (United States)

    Salmon-Ceron, Dominique; Mondelli, Mario U; Maticic, Mojca; Arends, Joop E

    2017-11-07

    This review aimed to examine mid-term liver complications and extra-hepatic clinical syndromes in addition to quality of life benefits associated with achieving HCV cure. Also to review the few safety issues that have been associated with the use of oral direct acting antivirals (DAAs) and discuss the potential benefits of the reduction of the burden of HCV infection at the population level. HCV cure is possible with DAAs in more than 95% of the patients treated. The blockage of liver inflammation and halting of fibrosis progression translates in both hepatic and extra-hepatic beneficial improvements and in reduction in the need for liver transplantation secondary to HCV. In addition, a reduction in the frequency of extra-hepatic manifestations like mixed cryoglobulinemia and vasculitis and improvements in quality of life and fatigue have been described. Curing HCV infection also provides a high potential to reduce the burden of HCV infection at the population level. Several modelling studies suggest that dramatic reductions in HCV prevalence and incidence are possible with large scaling-up of HCV treatment. However, obtaining these benefits needs early treatment of HCV-infected individuals preceded by voluntary national policies to improve the screening of HCV and the access to care, particularly in high-risk populations. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Trasmissione sessuale di HCV in coppie eterosessuali monogame

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    C. Vandelli

    2003-05-01

    Full Text Available

    Obiettivi: la trasmissione dell’HCV per via sessuale non è stata ancora confermata in modo inequivocabile. Dai dati della letteratura emerge che il tasso di infezione da HCV in partner sessuali di soggetti anti-HCV positivi varia da valori molto bassi a valori elevati (fino al 30%. Scopo dello studio è stato quello di valutare prospetticamente il rischio di acquisire l’infezione da HCV in una coorte di partner monogami di soggetti con infezione cronica da HCV.

    Metodi: è stata studiata una coorte di 895 partner sessuali monogami di soggetti HCV infetti afferenti al Dipartimento di Medicina Interna dell’Università di Modena. Le coppie sono state seguite prospetticamente per un periodo di 10 anni. I dati disponibili al termine del follow-up riguardavano 776 delle 895 (86.7% coppie arruolate. Tutte le coppie hanno negato rapporti anali, sesso durante il periodo mestruale o uso di profilattico. Il tasso medio settimanale di rapporti sessuali è risultato di 1.8. Tutti i soggetti sono stati annualmente testati per anti-HCV e HCV RNA. Risultati: durante il follow-up sono state osservate 3 nuove infezioni da HCV (tasso di incidenza = 0.37 per 1000 persone-anno. Tuttavia, il genotipo di HCV presente in un coniuge (2a era differente da quello del rispettivo partner (1b. Le rimanenti due coppie avevano genotipo concordante ma l’analisi filogenetica delle sequenze della regione NS5b del genoma di HCV ha indicato che gli isolati virali dei rispettivi partner erano differenti, escludendo quindi la possibilità di una trasmissione per via sessuale.

    Conclusioni: i dati del presente studio indicano che il rischio di trasmissione sessuale di HCV tra coppie eterosessuali monogame è estremamente basso o addirittura assente. Alcuna raccomandazione generale all’uso del profilattico sembra pertanto richiesta per coppie monogami con un partner HCV positivo.

  15. Activation of extrinsic apoptosis pathway in HCV monoinfected and HIV-HCV coinfected patients, irrespective of liver disease severity.

    Science.gov (United States)

    Feuth, Thijs; Van Baarle, Debbie; Hoepelman, Andy I M; Van Erpecum, Karel J; Siersema, Peter D; Arends, Joop E

    2014-07-01

    Chronic hepatitis C virus (HCV) infection is associated with increased levels of peripheral T cell apoptosis. We aimed to study whether T cell apoptosis markers indicate pathways that may contribute to clinical progression in HCV monoinfected and HIV-HCV coinfected patients. Activation of the extrinsic apoptosis pathways was measured by levels of death receptor Fas, initiator caspase 8 and effector caspases 3 and 7 activity and Annexin V binding on peripheral CD4 and CD8 T cells of HCV monoinfected and HIV/HCV coinfected patients, as well as healthy controls and HIV-infected, hepatitis B virus-infected and primary biliary cirrhosis disease controls. Association with liver fibrosis was assessed by biopsy or by transient elastography. HCV monoinfected and HIV-HCV coinfected patients displayed enhanced peripheral CD4 and CD8 T cell apoptosis. Caspase 8 activity was highest in HIV-HCV coinfection, without enhanced downstream activity of caspases 3 and 7. Level of peripheral T cell apoptosis was independent of liver fibrosis or other disease parameters in all disease groups. The extrinsic apoptosis pathway is upregulated in HCV monoinfection and HIV-HCV coinfection, but this is independent of liver disease severity.

  16. Why don't we treat chronic hepatitis C in HIV patients? Results from a cohort of HIV-HCV coinfected patients from the southeast of Spain

    Directory of Open Access Journals (Sweden)

    C Smilg Nicolás

    2012-11-01

    Full Text Available Purpose of the study: To know the different reasons why we decide not to treat or to delay the antiviral treatment against HCV in HIV coinfected patients. Methods: Prospective cohort of HIV and HCV coinfected patients, followed in the Infectious Diseases Department of the Santa Lucia Universitary Hospital (Cartagena, Spain between 1/12/2011 and 28/02/2012 in which we made transitory elastography. We evaluated the main reasons that moved us to decide not to treat or to delay the antiviral treatment against HCV: social-familiar-laboral reasons; neuro-psychiatric severe diseases; patient decision; low grade hepatic fibrosis; previous failure to pegylated interferon (IFN and ribavirin (RBV in no-1 genotype patients; delay in the approval of the triple therapy with INF-RBV and a protease inhibitor (boceprevir or telaprevir by the Regional Sanitary Authority; active alcohol abuse; active diseases that contraindicate the antiviral treatment, incomplete study of HCV (VL of HCV, genotype, ILB28, abdominal ecography; previous intolerance against IFN-RBV and severe thrombocytopenia (<50×109/L. Summary of results: The cohort included 109 patients, being 27 of them females (25% and 82 males (75%, with a median of age of 45.8 years (SD: 6.2. In 98 patients (90% we decided not to treat or to delay the antiviral treatment against HCV for one or more of the following reasons: 37 (34% presented low grade hepatic fibrosis (<9.5 kpascal or F0-F2; 19 (17% had neuro-psychiatric diseases; 18 (16.5% were waiting for the approval of triple therapy by the Regional Sanitary Authority; 10 (9.2% did not want to be treated; 10 (9.2% had failure to IFN-RBV in no-1 genotype; 6 (5.5% had social-familiar-laboral reasons; 6 (5.5% presented active severe diseases; 4 (3.7% were waiting to complete HCV study; 3 (2.8% presented active alcohol abuse; 3 (2.8% had previous intolerance against IFN-RBV treatment and 2 (2% had severe thrombocytopenia. Conclusions: In our cohort of HIV-HCV

  17. Present situation of antiviral therapies for HCV-related cirrhosis

    Directory of Open Access Journals (Sweden)

    LI Qiang

    2015-11-01

    Full Text Available Patients with hepatitis C virus (HCV-related cirrhosis are at a higher risk for the development of hepatic failure and hepatocellular carcinoma (HCC compared with non-cirrhotic patients. Antiviral therapies for HCV-related cirrhosis may reduce the incidence of HCC and hepatic failure. This article introduces current antiviral therapies for HCV-related cirrhosis: P/R, DAA+P/R, and IFN-free regimens, and summarizes the present situation of antiviral therapies for HCV-related cirrhosis. It is thought that the advent of direct-acting antivirals has improved the rate of sustained virologic response and reduced the incidence of adverse events during the treatment of HCV-related cirrhosis. Interferon-free regimens have great advantage and potential in antiviral therapies for HCV-related cirrhosis.

  18. Mechanisms of accelerated liver fibrosis in HIV-HCV coinfection.

    Science.gov (United States)

    Chrysanthidis, Theofilos; Loli, Georgia; Metallidis, Simeon; Germanidis, Georgios

    2017-01-01

    Although there is evidence that HCV progresses rapidly in HIV/HCV coinfected patients in comparison with HCV monoinfected, the HIV-, HCV- and host/genetic-related factors, as well as the exact mechanisms implicated in this process are not fully elucidated. Furthermore, cure of HCV in those coinfected seems possible with the new antiviral drugs, but high cost as well as insufficient identification, linkage with care and treatment hamper the achievement of this goal. Research on the subject, could reveal an important prognostic marker for the effectiveness of persuasion of patients with HIV/HCV coinfection with a predicted accelerated fibrosis course, in order to facilitate and prioritize, not in terms of guidelines but in the real life situation, their treatment with a medically just framework.

  19. Virological Mechanisms in the Coinfection between HIV and HCV

    Directory of Open Access Journals (Sweden)

    Maria Carla Liberto

    2015-01-01

    Full Text Available Due to shared transmission routes, coinfection with Hepatitis C Virus (HCV is common in patients infected by Human Immunodeficiency Virus (HIV. The immune-pathogenesis of liver disease in HIV/HCV coinfected patients is a multifactorial process. Several studies demonstrated that HIV worsens the course of HCV infection, increasing the risk of cirrhosis and hepatocellular carcinoma. Also, HCV might increase immunological defects due to HIV and risk of comorbidities. A specific cross-talk among HIV and HCV proteins in coinfected patients modulates the natural history, the immune responses, and the life cycle of both viruses. These effects are mediated by immune mechanisms and by a cross-talk between the two viruses which could interfere with host defense mechanisms. In this review, we focus on some virological/immunological mechanisms of the pathogenetic interactions between HIV and HCV in the human host.

  20. Impaired Hepatitis C Virus (HCV)–Specific Interferon-γ Responses in Individuals With HIV Who Acquire HCV Infection: Correlation With CD4+ T-Cell Counts

    Science.gov (United States)

    Flynn, Jacqueline K.; Dore, Gregory J.; Matthews, Gail; Hellard, Margaret; Yeung, Barbara; Rawlinson, William D.; White, Peter A.; Kaldor, John M.; Lloyd, Andrew R.; Ffrench, Rosemary A.

    2012-01-01

    Studies examining the effect of coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) on the HCV-specific immune response in acute HCV infection are limited. This study directly compared acute HCV-specific T-cell responses and cytokine profiles between 20 HIV/HCV-coinfected and 20 HCV-monoinfected subjects, enrolled in the Australian Trial in Acute Hepatitis C (ATAHC), using HCV peptide enzyme-linked immunospot (ELISPOT) and multiplex in vitro cytokine production assays. HIV/HCV coinfection had a detrimental effect on the HCV-specific cytokine production in acute HCV infection, particularly on HCV-specific interferon γ (IFN-γ) production (magnitude P = .004; breadth P = .046), which correlated with peripheral CD4+ T-cell counts (ρ = 0.605; P = .005) but not with detectable HIV viremia (ρ = 0.152; P = .534). PMID:22949308

  1. Impaired hepatitis C virus (HCV)-specific interferon-γ responses in individuals with HIV who acquire HCV infection: correlation with CD4(+) T-cell counts.

    Science.gov (United States)

    Flynn, Jacqueline K; Dore, Gregory J; Matthews, Gail; Hellard, Margaret; Yeung, Barbara; Rawlinson, William D; White, Peter A; Kaldor, John M; Lloyd, Andrew R; Ffrench, Rosemary A

    2012-11-15

    Studies examining the effect of coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) on the HCV-specific immune response in acute HCV infection are limited. This study directly compared acute HCV-specific T-cell responses and cytokine profiles between 20 HIV/HCV-coinfected and 20 HCV-monoinfected subjects, enrolled in the Australian Trial in Acute Hepatitis C (ATAHC), using HCV peptide enzyme-linked immunospot (ELISPOT) and multiplex in vitro cytokine production assays. HIV/HCV coinfection had a detrimental effect on the HCV-specific cytokine production in acute HCV infection, particularly on HCV-specific interferon γ (IFN-γ) production (magnitude P = .004; breadth P = .046), which correlated with peripheral CD4(+) T-cell counts (ρ = 0.605; P = .005) but not with detectable HIV viremia (ρ = 0.152; P = .534).

  2. Anti-Hepatitis C Virus Activity of a Crude Extract from Longan (Dimocarpus longan Lour.) Leaves.

    Science.gov (United States)

    Apriyanto, Dadan Ramadhan; Aoki, Chie; Hartati, Sri; Hanafi, Muhammad; Kardono, Leonardus Broto Sugeng; Arsianti, Ade; Louisa, Melva; Sudiro, Tjahjani Mirawati; Dewi, Beti Ernawati; Sudarmono, Pratiwi; Soebandrio, Amin; Hotta, Hak

    2016-05-20

    Infection with hepatitis C virus (HCV) results in hepatitis C, a disease characterized by chronic infection, cirrhosis, and hepatocellular carcinoma. Currently, the standard therapy is a combination of pegylated interferon-α plus ribavirin with NS3 protease inhibitors. Addition of NS3 protease inhibitors to the standard therapy improves response rates; however, use of NS3 protease inhibitors is also associated with significant adverse effects and an increase in the overall cost of treatment. Therefore, there is a need to develop safe and inexpensive drugs for the treatment of HCV infections. In this study, we examined the antiviral activity of a crude extract from Dimocarpus longan leaves against HCV (genotype 2a strain JFH1). The D. longan crude extract (DL-CE) exhibited anti-HCV activity with a 50% effective concentration (EC50) of 19.4 μg/ml without cytotoxicity. A time-of-addition study demonstrated that DL-CE has anti-HCV activity at both the entry and post-entry steps and markedly blocks the viral entry step through direct virucidal activity with marginal inhibition of virion assembly. Co-treatment of DL-CE with cyclosporine A, an immunosuppressant or telaprevir, an NS3 protease inhibitor, resulted in additive and synergistic antiviral effects, respectively. Our findings suggest that DL-CE may be useful as an add-on therapy candidate for treating HCV infections.

  3. Proteochemometric modeling of HIV protease susceptibility

    National Research Council Canada - National Science Library

    Lapins, Maris; Eklund, Martin; Spjuth, Ola; Prusis, Peteris; Wikberg, Jarl E S

    2008-01-01

    .... Therefore, we used proteochemometrics to model the susceptibility of HIV to protease inhibitors in current use, utilizing descriptions of the physico-chemical properties of mutated HIV proteases...

  4. Detection limit of architect hepatitis C core antigen assay in correlation with HCV RNA, and renewed confirmation algorithm for reactive anti-HCV samples.

    Science.gov (United States)

    Ottiger, Cornelia; Gygli, Nicole; Huber, Andreas R

    2013-11-01

    hepatitis C infections are detected by anti-HCV screening tests. Reactive anti-HCV results give no information about the presence or absence of hepatitis C viruses, or of unspecific reactivity. To obtain information about the viral load, HCV RNA measurements, following a reactive anti-HCV result, are performed in well equipped and specialised laboratories. Anti-HCV immunoblots are the only means to exclude non specific reactivity. The measurement of HCV core antigen (HCV-Ag), as an alternative to HCV RNA, is discussed, as it can be analysed on the same instrument as anti-HCV. The detection limit of HCV-Ag is crucial to use it in lieu of HCV RNA, in regard of the different genotypes. A renewed algorithm is proposed to exclude unspecific reactivity of anti-HCV. Samples were tested on Architect i2000SR (Abbott) for anti-HCV and HCV-Ag. HCV RNA measurements were obtained by Cobas Ampliprep/Taqman (Roche) or m2000rt(®) (Abbott). Comparison between HCV-Ag and HCV RNA from 126 samples of 101 patients with chronic hepatitis C gave linear regression R(2) 0.89, slope 0.885 and intercept -2.258, which were independent of the genotypes. The detection limit of HCV-Ag was between 2.4 and 4.5 Log(10)IU/mL. A renewed algorithm for confirmation of reactive anti-HCV results is proposed: active or resolved hepatitis C infections or false reactivity can be differentiated by sequenced reflex testing due to HCV-Ag, anti-HCV immunoblot and HCV RNA. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Animal models for HCV and HBV studies

    Directory of Open Access Journals (Sweden)

    Isabelle Chemin

    2007-02-01

    Full Text Available

    The narrow host range of infection and lack of suitable tissue culture systems for the propagation of hepatitis B and C viruses are limitations that have prevented a more thorough understanding of persistent infection and the pathogenesis of chronic liver disease.

    Despite decades of intensive research and significant progresses in understanding of viral hepatitis, many basic questions and clinical problems still await to be resolved. For example, the HBV cellular receptor and related mechanisms of viral entry have not yet been identified. Little is also known about the function of certain non-structural viral products, such as the hepatitis B e antigen and the X protein, or about the role of excess hepadnavirus subviral particles circulating in the blood stream during infection. Furthermore, the molecular mechanisms involved in the development of hepatocellular carcinoma and the role of the immune system in determining the fate of infection are not fully understood.

    The reason for these drawbacks is essentially due to the lack of reliable cell-based in vitro infection systems and, most importantly, convenient animal models.

    This lack of knowledge has been partially overcome for hepatitis B virus (HBV, by the discovery and characterization of HBV-like viruses in wild animals while for hepatitis C virus (HCV, related flaviviruses have been used as surrogate systems.

    Other laboratories have developed transgenic mice that express virus gene products and/or support virus replication. Some HBV transgenic mouse models

  6. Discovery of potent macrocyclic HCV NS5A inhibitors.

    Science.gov (United States)

    Yu, Wensheng; Vibulbhan, Bancha; Rosenblum, Stuart B; Martin, Gregory S; Vellekoop, A Samuel; Holst, Christian L; Coburn, Craig A; Wong, Michael; Selyutin, Oleg; Ji, Tao; Zhong, Bin; Hu, Bin; Chen, Lei; Dwyer, Michael P; Jiang, Yueheng; Nair, Anilkumar G; Tong, Ling; Zeng, Qingbei; Agrawal, Sony; Carr, Donna; Rokosz, Laura; Liu, Rong; Curry, Stephanie; McMonagle, Patricia; Ingravallo, Paul; Lahser, Fred; Asante-Appiah, Ernest; Fells, James; Kozlowski, Joseph A

    2016-08-01

    HCV NS5A inhibitors have demonstrated impressive in vitro virologic profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed-dose combination (FDC) regimen for the treatment of HCV infection. Merck's effort in this area identified MK-4882 and MK-8325 as early development leads. Herein, we describe the discovery of potent macrocyclic NS5A inhibitors bearing the MK-8325 or MK-4882 core structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. In-vitro antiviral activity of Solanum nigrum against Hepatitis C Virus

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    Rehman Sidra

    2011-01-01

    Full Text Available Abstract Background Hepatitis C is a major health problem causes liver cirrhosis, hepatocellular carcinoma and death. The current treatment of standard interferon in combination with ribavirin, has limited benefits due to emergence of resistant mutations during long-term treatment, adverse side effects and high cost. Hence, there is a need for the development of more effective, less toxic antiviral agents. Results The present study was designed to search anti-HCV plants from different areas of Pakistan. Ten medicinal plants were collected and tested for anti-HCV activity by infecting the liver cells with HCV 3a innoculum. Methanol and chloroform extracts of Solanum nigrum (SN seeds exhibited 37% and more than 50% inhibition of HCV respectively at non toxic concentration. Moreover, antiviral effect of SN seeds extract was also analyzed against HCV NS3 protease by transfecting HCV NS3 protease plasmid into liver cells. The results demonstrated that chloroform extract of SN decreased the expression or function of HCV NS3 protease in a dose- dependent manner and GAPDH remained constant. Conclusion These results suggest that SN extract contains potential antiviral agents against HCV and combination of SN extract with interferon will be better option to treat chronic HCV.

  8. Hepatitis C virus (HCV genotype 1 subtype identification in new HCV drug development and future clinical practice.

    Directory of Open Access Journals (Sweden)

    Stéphane Chevaliez

    Full Text Available BACKGROUND: With the development of new specific inhibitors of hepatitis C virus (HCV enzymes and functions that may yield different antiviral responses and resistance profiles according to the HCV subtype, correct HCV genotype 1 subtype identification is mandatory in clinical trials for stratification and interpretation purposes and will likely become necessary in future clinical practice. The goal of this study was to identify the appropriate molecular tool(s for accurate HCV genotype 1 subtype determination. METHODOLOGY/PRINCIPAL FINDINGS: A large cohort of 500 treatment-naïve patients eligible for HCV drug trials and infected with either subtype 1a or 1b was studied. Methods based on the sole analysis of the 5' non-coding region (5'NCR by sequence analysis or reverse hybridization failed to correctly identify HCV subtype 1a in 22.8%-29.5% of cases, and HCV subtype 1b in 9.5%-8.7% of cases. Natural polymorphisms at positions 107, 204 and/or 243 were responsible for mis-subtyping with these methods. A real-time PCR method using genotype- and subtype-specific primers and probes located in both the 5'NCR and the NS5B-coding region failed to correctly identify HCV genotype 1 subtype in approximately 10% of cases. The second-generation line probe assay, a reverse hybridization assay that uses probes targeting both the 5'NCR and core-coding region, correctly identified HCV subtypes 1a and 1b in more than 99% of cases. CONCLUSIONS/SIGNIFICANCE: In the context of new HCV drug development, HCV genotyping methods based on the exclusive analysis of the 5'NCR should be avoided. The second-generation line probe assay is currently the best commercial assay for determination of HCV genotype 1 subtypes 1a and 1b in clinical trials and practice.

  9. HCV-RNA quantification in liver bioptic samples and extrahepatic compartments, using the abbott RealTime HCV assay.

    Science.gov (United States)

    Antonucci, FrancescoPaolo; Cento, Valeria; Sorbo, Maria Chiara; Manuelli, Matteo Ciancio; Lenci, Ilaria; Sforza, Daniele; Di Carlo, Domenico; Milana, Martina; Manzia, Tommaso Maria; Angelico, Mario; Tisone, Giuseppe; Perno, Carlo Federico; Ceccherini-Silberstein, Francesca

    2017-08-01

    We evaluated the performance of a rapid method to quantify HCV-RNA in the hepatic and extrahepatic compartments, by using for the first time the Abbott RealTime HCV-assay. Non-tumoral (NT), tumoral (TT) liver samples, lymph nodes and ascitic fluid from patients undergoing orthotopic-liver-transplantation (N=18) or liver resection (N=4) were used for the HCV-RNA quantification; 5/22 patients were tested after or during direct acting antivirals (DAA) treatment. Total RNA and DNA quantification from tissue-biopsies allowed normalization of HCV-RNA concentrations in IU/μg of total RNA and IU/10 6 liver-cells, respectively. HCV-RNA was successfully quantified with high reliability in liver biopsies, lymph nodes and ascitic fluid samples. Among the 17 untreated patients, a positive and significant HCV-RNA correlation between serum and NT liver-samples was observed (Pearson: rho=0.544, p=0.024). Three DAA-treated patients were HCV-RNA "undetectable" in serum, but still "detectable" in all tested liver-tissues. Differently, only one DAA-treated patient, tested after sustained-virological-response, showed HCV-RNA "undetectability" in liver-tissue. HCV-RNA was successfully quantified with high reliability in liver bioptic samples and extrahepatic compartments, even when HCV-RNA was "undetectable" in serum. Abbott RealTime HCV-assay is a good diagnostic tool for HCV quantification in intra- and extra-hepatic compartments, whenever a bioptic sample is available. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Therapeutic vaccines in HBV: lessons from HCV.

    Science.gov (United States)

    Barnes, Eleanor

    2015-02-01

    Currently, millions of people infected with hepatitis B virus (HBV) are committed to decades of treatment with anti-viral therapy to control viral replication. However, new tools for immunotherapy that include both viral vectors and molecular checkpoint inhibitors are now available. This has led to a resurgence of interest in new strategies to develop immunotherapeutic strategies with the aim of inducing HBeAg seroconversion--an end-point that has been associated with a decrease in the rates of disease progression. Ultimately, a true cure will involve the elimination of covalently closed circular DNA which presents a greater challenge for immunotherapy. In this manuscript, I describe the development of immunotherapeutic strategies for HBV that are approaching or currently in clinical studies, and draw on observations of T cell function in natural infection supported by recent animal studies that may lead to additional rational vaccine strategies using checkpoint inhibitors. I also draw on our recent experience in developing potent vaccines for HCV prophylaxis based on simian adenoviral and MVA vectors used in prime-boost strategies in both healthy volunteers and HCV infected patients. I have shown that the induction of T cell immune responses is markedly attenuated when administered to people with persistent HCV viremia. These studies and recently published animal studies using the woodchuck model suggest that potent vaccines based on DNA or adenoviral vectored vaccination represent a rational way forward. However, combining these with drugs to suppress viral replication, alongside checkpoint inhibitors may be required to induce long-term immune control.

  11. Modeling HCV disease in animals: virology, immunology and pathogenesis of HCV and GBV-B infections.

    Science.gov (United States)

    Manickam, Cordelia; Reeves, R Keith

    2014-01-01

    Hepatitis C virus (HCV) infection has become a global public health burden costing billions of dollars in health care annually. Even with rapidly advancing scientific technologies this disease still poses a significant threat due to a lack of vaccines and affordable treatment options. The immune correlates of protection and predisposing factors toward chronicity remain major obstacles to development of HCV vaccines and immunotherapeutics due, at least in part, to lack of a tangible infection animal model. This review discusses the currently available animal models for HCV disease with a primary focus on GB virus B (GBV-B) infection of New World primates that recapitulates the dual Hepacivirus phenotypes of acute viral clearance and chronic pathologic disease. HCV and GBV-B are also closely phylogenetically related and advances in characterization of the immune systems of New World primates have already led to the use of this model for drug testing and vaccine trials. Herein, we discuss the benefits and caveats of the GBV-B infection model and discuss potential avenues for future development of novel vaccines and immunotherapies.

  12. Modeling HCV Disease in Animals: Virology, Immunology and Pathogenesis of HCV and GBV-B Infections

    Directory of Open Access Journals (Sweden)

    Cordelia eManickam

    2014-12-01

    Full Text Available Hepatitis C virus (HCV infection has become a global public health burden costing billions of dollars in health care annually. Even with rapidly advancing scientific technologies, this disease still looms large due to a lack of vaccines and affordable treatment options. The immune correlates of protection and predisposing factors towards chronicity remain major obstacles to development of HCV vaccines and immunotherapeutics due, at least in part, to lack of a tangible infection animal model. This review discusses the currently available animal models for HCV disease, with a primary focus on GB virus B (GBV-B infection of New World primates that recapitulates the dual hepacivirus phenotypes of acute viral clearance and chronic pathologic disease. HCV and GBV-B are also closely phylogenetically related, and advances in characterization of the immune systems of New World primates have already led to the use of this model for drug testing and vaccine trials. Herein, we discuss the benefits and caveats of the GBV-B infection model and discuss potential avenues for future development of novel vaccines and immunotherapies.

  13. Molecular epidemiology of HCV monoinfection and HIV/HCV coinfection in injection drug users in Liuzhou, Southern China.

    Directory of Open Access Journals (Sweden)

    Yi Tan

    Full Text Available BACKGROUND: Hepatitis C virus (HCV mono-infection and HCV/HIV (human immunodeficiency virus co-infection are growing problems in injection drug users (IDU. Their prevalence and genotypic patterns vary with geographic locations. Access to harm reduction measures is opening up opportunities for improving the HIV/HCV profiling of IDU in China, where IDUs account for a significant proportion of the two infections especially in the southern part of the country. METHODOLOGY/PRINCIPAL FINDINGS: A cross sectional study was conducted. Through the Liuzhou Methadone Clinic, a total of 117 injection drug users (IDUs were recruited from Guangxi, Southern China. A majority of the IDUs (96% were HCV antibody positive, of which 21% were HIV infected. Unlike HCV monoinfection, there was spatial heterogeneity in the distribution of HIV/HCV coinfection, the latter also characterized by a higher prevalence of needle-sharing. Phylogenetic analysis revealed that genotype 6a was predominant in the study population. There were shorter genetic distances among the 6a sequences compared to the other HCV subtypes-1a, 3a, and 3b. CONCLUSION/SIGNIFICANCE: The results suggested that HIV and HCV were introduced at around the same time to the IDU populations in Southern China, followed by their differential spread as determined by the biologic characteristics of the virus and the intensity of behavioural risk. This pattern is different from that in other South East Asian countries where HCV infections have probably predated HIV.

  14. A randomized trial of daclatasvir with peginterferon alfa-2b and ribavirin for HCV genotype 1 infection.

    Science.gov (United States)

    Suzuki, Fumitaka; Toyota, Joji; Ikeda, Kenji; Chayama, Kazuaki; Mochida, Satoshi; Hayashi, Norio; Ishikawa, Hiroki; Miyagoshi, Hidetaka; Hu, Wenhua; McPhee, Fiona; Hughes, Eric A; Kumada, Hiromitsu

    2014-01-01

    Daclatasvir-containing regimens have the potential to address limitations of current regimens combining peginterferon alfa and ribavirin with first-generation protease inhibitors for treatment of chronic HCV genotype 1 infection. In this randomized, double-blind study, 27 Japanese treatment-naive patients received once-daily daclatasvir 10 mg or 60 mg or placebo, each combined with peginterferon alfa-2b/ribavirin; 18 prior null (n=9) or partial (n=9) responders received the same daclatasvir-containing regimens without a placebo arm. Daclatasvir recipients with protocol-defined response (HCV RNAdaclatasvir 10 mg, 60 mg and placebo groups, respectively. Prior non-responders had more frequent virological failure; 22.2% and 33.3% of daclatasvir 10 mg and 60 mg recipients, respectively, achieved SVR24. Adverse events were similar across groups and were typical of peginterferon alfa-2b/ribavirin. Pyrexia, headache, alopecia, decreased appetite and malaise were the most common adverse events; two daclatasvir recipients discontinued due to adverse events. Daclatasvir 60 mg combined with peginterferon alfa-2b and ribavirin achieved a high rate of SVR24 in treatment-naive patients with HCV genotype 1 infection, with tolerability similar to that of peginterferon alfa-2b/ribavirin alone. However, regimens with greater antiviral potency are needed for prior non-responders.

  15. Stability of hepatitis C virus (HCV) RNA levels among interferon-naïve HIV/HCV-coinfected individuals treated with combination antiretroviral therapy

    DEFF Research Database (Denmark)

    Grint, D; Peters, L; Reekie, J

    2013-01-01

    Infection with hepatitis C virus (HCV) is a major cause of chronic liver disease. High HCV RNA levels have been associated with poor treatment response. This study aimed to examine the natural history of HCV RNA in chronically HCV/HIV-coinfected individuals....

  16. Structure of a murine norovirus NS6 protease-product complex revealed by adventitious crystallisation.

    Directory of Open Access Journals (Sweden)

    Eoin N Leen

    Full Text Available Murine noroviruses have emerged as a valuable tool for investigating the molecular basis of infection and pathogenesis of the closely related human noroviruses, which are the major cause of non-bacterial gastroenteritis. The replication of noroviruses relies on the proteolytic processing of a large polyprotein precursor into six non-structural proteins (NS1-2, NS3, NS4, NS5, NS6(pro, NS7(pol by the virally-encoded NS6 protease. We report here the crystal structure of MNV NS6(pro, which has been determined to a resolution of 1.6 Å. Adventitiously, the crystal contacts are mediated in part by the binding of the C-terminus of NS6(pro within the peptide-binding cleft of a neighbouring molecule. This insertion occurs for both molecules in the asymmetric unit of the crystal in a manner that is consistent with physiologically-relevant binding, thereby providing two independent views of a protease-peptide complex. Since the NS6(pro C-terminus is formed in vivo by NS6(pro processing, these crystal contacts replicate the protease-product complex that is formed immediately following cleavage of the peptide bond at the NS6-NS7 junction. The observed mode of binding of the C-terminal product peptide yields new insights into the structural basis of NS6(pro specificity.

  17. Post-transcriptional inhibition of hepatitis C virus replication through small interference RNA

    Directory of Open Access Journals (Sweden)

    Rehman Sidra

    2011-03-01

    Full Text Available Abstract Background Hepatitis C Virus (HCV infection is a major health problem throughout world that causes acute and chronic infection which resulted in liver fibrosis, hepatocellular carcinoma and death. The only therapy currently available for HCV infection is the combination of pegylated interferon alpha (PEG-IFN α and ribavirin. This therapy can effectively clear the virus infection in only 50% of infected individuals. Hence, there is a dire need to develop antiviral agents against HCV. Results This study was design to examine the ability of exogenous small interfering RNAs (siRNAs to block the replication of HCV in human liver cells. In the present study six 21-bp siRNAs were designed against different regions of HCV non-structural genes (NS2, NS3 serine protease/helicase, NS4Band NS5B RNA dependent RNA polymerase. siRNAs were labeled as NS2si241, NS3si-229, NS3si-858, NS4Bsi-166, NS5Bsi-241 and NS5Bsi-1064. We found that siRNAs against HCV NS2- NS5B efficiently inhibit HCV replication in Huh-7 cells. Our results demonstrated that siRNAs directed against HCV NS3 (NS3si-229 and NS3si-858 showed 58% and 88% reduction in viral titer respectively. Moreover, NS4Bsi-166 and NS5Bsi-1064 exhibited a dramatic reduction in HCV viral RNA and resulted in greater than 90% inhibition at a 20 μM concentration, while NS2si-241 showed 27% reduction in viral titer. No significant inhibition was detected in cells transfected with the negative control siRNA. Conclusion Our results suggest that siRNAs targeting against HCV non-structural genes (NS2-NS5B efficiently inhibit HCV replication and combination of these siRNAs of different targets and interferon will be better option to treat HCV infection throughout the world.

  18. Protease-Sensitive Synthetic Prions

    OpenAIRE

    Colby, David W.; Wain, Rachel; Baskakov, Ilia V.; Legname, Giuseppe; Palmer, Christina G.; Nguyen, Hoang-Oanh B.; Lemus, Azucena; Cohen, Fred E.; DeArmond, Stephen J.; Prusiner, Stanley B.

    2010-01-01

    Prions arise when the cellular prion protein (PrPC) undergoes a self-propagating conformational change; the resulting infectious conformer is designated PrPSc. Frequently, PrPSc is protease-resistant but protease-sensitive (s) prions have been isolated in humans and other animals. We report here that protease-sensitive, synthetic prions were generated in vitro during polymerization of recombinant (rec) PrP into amyloid fibers. In 22 independent experiments, recPrP amyloid preparations, but no...

  19. Partial Purification and Characterization of Extracellular Protease ...

    African Journals Online (AJOL)

    Microbial proteases have wide industrial applications and proteases of the lactic acid bacteria (LAB) have received special attention because of their importance in the ... The crude protease had temperature and pH optima of 28 oC and 4.0 respectively thus indicating that the enzyme is a mesophilic and acidic protease.

  20. HCV clearance patterns in saliva and serum of patients with chronic HCV infection under interferon plus ribavirin therapy.

    Science.gov (United States)

    Diz Dios, P; Castro, A; Rodríguez, I; Reforma, N G; Castro, M; Eirea, M; Hermida, M

    2005-05-01

    Hepatitis C virus (HCV)-RNA is often present in saliva of HCV-infected patients, with plasma viral load being the only known predictable factor. Interferon plus ribavirin therapy yields a sustained reduction in HCV viremia. This study aimed to assess the presence of HCV in saliva and serum specimens from patients undergoing this combination therapy (CT). Paired serum and saliva specimens were collected from 44 chronic HCV-infected patients at basal time, 4 and 12 weeks after CT onset, at the end of treatment and 6 months latter. Serum HCV-RNA levels were determined by the polymerase chain reaction (PCR) Amplicor system. Presence of HCV-RNA in saliva was tested by a highly sensitive non-commercialized nested-PCR. The HCV-RNA was detected in 26 saliva specimens at basal time (59.1%). In 34.1% of cases, a concordance viral clearance pattern in serum and saliva was observed in both responders (pattern 1a) and non-responders (pattern 1b). In pattern 2 (13.6% of cases), HCV was detected longer during CT in serum than in saliva (pattern 2a) or in saliva than in serum (pattern 2b). In 11.3% of patients, viral clearance was corroborated either in their serum (pattern 3a) or in their saliva (pattern 3b), but not in both fluids. Of the eight primary responders with 1a clearance pattern, seven were sustained responders. None of the patients with 2a clearance pattern was a sustained responder. Of the two primary responders showing the 3b salivary pattern, one had already relapsed in the first 6 months of follow up. The present results suggest that the monitoring of salivary levels of HCV would be a helpful means of determining sustained antiviral effects of interferon and ribavirin in the treatment of HCV disease.

  1. Expression of chimeric HCV peptide in transgenic tobacco plants ...

    African Journals Online (AJOL)

    Using plant-virus based transient expression to produce this unique chimeric antigen will facilitate the development and production of an experimental HCV vaccine. A plant derived recombinant HCV vaccine can potentially reduce expenses normally associated with production and delivery of conventional vaccine.

  2. Seroprevalence of Hepatitis C Virus (HCV) antibodies in pregnant ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) infection is a major public health concern. The aim of this study was to ascertain the seroprevalence and risk factors of HCV antibodies among pregnant women in Anyigba, Kogi State North Central Nigeria. Materials and methods:Blood samples (5mls) were collected from one hundred ...

  3. Historical epidemiology of hepatitis C virus (HCV) in selected countries

    DEFF Research Database (Denmark)

    Bruggmann, P; Berg, T; Øvrehus, A L H

    2014-01-01

    Chronic infection with hepatitis C virus (HCV) is a leading indicator for liver disease. New treatment options are becoming available, and there is a need to characterize the epidemiology and disease burden of HCV. Data for prevalence, viremia, genotype, diagnosis and treatment were obtained thro...

  4. Relation of HCV induced insulin resitance and Hepatocellular ...

    African Journals Online (AJOL)

    It could be concluded from this work that HCV-related metabolic complications as hepatic steatosis and IR may be associated with increased risk of HCC development. c.335T>C and c.3073A>C SNPs of MDR1 gene could be considered as a possible molecular candidates for the HCC development in chronic HCV patients.

  5. Hepatitis C virus (HCV): ever in reliable partnerships? | Yalena ...

    African Journals Online (AJOL)

    There is no preventive vaccine against HCV and treatment, consisting of interferon alpha plus Ribavirin, is generally effective in less than 50% of cases. HCV has evolved ... Issues regarding tropism, disease progression and antiviral treatment response, among other aspects, are discussed. Data accumulated reveal that ...

  6. Correlation between alanine aminotransferase level, HCV-RNA titer ...

    African Journals Online (AJOL)

    Reham Al Swaff

    2012-04-04

    Apr 4, 2012 ... Abstract The relationship of serum alanine aminotransferase (ALT) level and viral replication to liver damage in chronic hepatitis C virus (HCV) patients remains unclear. The aim of the present study was to determine whether the stage of fibrosis correlates with HCV-. RNA titer and/or serum ALT level in ...

  7. HCV-related liver cancer in people with haemophilia

    NARCIS (Netherlands)

    Meijer, K.; Haagsma, E. B.

    . The topic of this monograph is liver cancer associated with chronic HCV infection. We start with some background information on chronic HCV infection and its long-term sequelae, one of which is liver cancer. The rest of the article is concerned with liver cancer or hepatocellular carcinoma (HCC).

  8. Treatment of HCV Infection by Targeting MicroRNA

    NARCIS (Netherlands)

    Janssen, Harry L. A.; Reesink, Hendrik W.; Lawitz, Eric J.; Zeuzem, Stefan; Rodriguez-Torres, Maribel; Patel, Keyur; van der Meer, Adriaan J.; Patick, Amy K.; Chen, Alice; Zhou, Yi; Persson, Robert; King, Barney D.; Kauppinen, Sakari; Levin, Arthur A.; Hodges, Michael R.

    2013-01-01

    BACKGROUND The stability and propagation of hepatitis C virus (HCV) is dependent on a functional interaction between the HCV genome and liver-expressed microRNA-122 (miR-122). Miravirsen is a locked nucleic acid-modified DNA phosphorothioate antisense oligonucleotide that sequesters mature miR-122

  9. HCV RNA in peripheral blood mononuclear cells (PBMCs) as a ...

    African Journals Online (AJOL)

    Abdel Fatah Fahmy Hanno

    2013-06-27

    Jun 27, 2013 ... Abstract Background: Hepatitis C virus (HCV) has been found to infect peripheral blood mono- nuclear cells (PBMCs), using them as a reservoir, which might contribute to the development of resistance to treatment. Objectives: To study hepatitis virus C (HCV) RNA in peripheral blood mononuclear cells.

  10. HCV RNA in peripheral blood mononuclear cells (PBMCs) as a ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) has been found to infect peripheral blood mononuclear cells (PBMCs), using them as a reservoir, which might contribute to the development of resistance to treatment. Objectives: To study hepatitis virus C (HCV) RNA in peripheral blood mononuclear cells (PBMCs) of patients with ...

  11. Co-evolution of insect proteases and plant protease inhibitors.

    Science.gov (United States)

    Jongsma, Maarten A; Beekwilder, Jules

    2011-08-01

    Plants are at the basis of the food chain, but there is no such thing as a "free lunch" for herbivores. To promote reproductive success, plants evolved multi-layered defensive tactics to avoid or discourage herbivory. To the detriment of plants, herbivores, in turn, evolved intricate strategies to find, eat, and successfully digest essential plant parts to raise their own offspring. In this battle the digestive tract is the arena determining final victory or defeat as measured by growth or starvation of the herbivore. Earlier, specific molecular opponents were identified as proteases and inhibitors: digestive proteases of herbivores evolved structural motifs to occlude plant protease inhibitors, or alternatively, the insects evolved proteases capable of specifically degrading the host plant inhibitors. In response plant inhibitors evolved hyper-variable and novel protein folds to remain active against potential herbivores. At the level of protease regulation in herbivorous insects, it was shown that inhibition-insensitive digestive proteases are up-regulated when sensitive proteases are inhibited. The way this regulation operates in mammals is known as negative feedback by gut-luminal factors, so-called 'monitor peptides' that are sensitive to the concentration of active enzymes. We propose that regulation of gut enzymes by endogenous luminal factors has been an open invitation to plants to "hijack" this regulation by evolving receptor antagonists, although yet these plant factors have not been identified. In future research the question of the co-evolution of insect proteases and plant inhibitors should, therefore, be better approached from a systems level keeping in mind that evolution is fundamentally opportunistic and that the plant's fitness is primarily improved by lowering the availability of essential amino acids to an herbivore by any available mechanism.

  12. Immune Responses to HCV and Other Hepatitis Viruses

    Science.gov (United States)

    Park, Su-Hyung; Rehermann, Barbara

    2014-01-01

    Summary Five human hepatitis viruses cause most acute and chronic liver disease worldwide. Over the past 25 years hepatitis C virus (HCV) in particular has received much interest because of its ability to persist in most immunocompetent adults and the lack of a protective vaccine. Here we examine innate and adaptive immune responses to HCV infection. Although HCV activates an innate immune response, it employs an elaborate set of mechanisms to evade interferon (IFN)-based antiviral immunity. By comparing innate and adaptive immune responses to HCV with those to hepatitis A and B viruses, we suggest that prolonged innate immune activation impairs the development of successful adaptive immune responses. Comparative immunology furthermore provides insights into the maintenance of immune protection. We conclude by discussing prospects for an HCV vaccine and future research needs for the hepatitis viruses. PMID:24439265

  13. An overview of HCV molecular biology, replication and immune responses

    Directory of Open Access Journals (Sweden)

    Nawaz Zafar

    2011-04-01

    Full Text Available Abstract Hepatitis C virus (HCV causes acute and chronic hepatitis which can eventually lead to permanent liver damage, hepatocellular carcinoma and death. Currently, there is no vaccine available for prevention of HCV infection due to high degree of strain variation. The current treatment of care, Pegylated interferon α in combination with ribavirin is costly, has significant side effects and fails to cure about half of all infections. In this review, we summarize molecular virology, replication and immune responses against HCV and discussed how HCV escape from adaptive and humoral immune responses. This advance knowledge will be helpful for development of vaccine against HCV and discovery of new medicines both from synthetic chemistry and natural sources.

  14. Recent advances in the anti-HCV mechanisms of interferon

    Directory of Open Access Journals (Sweden)

    Menghao Huang

    2014-08-01

    Full Text Available Interferon (IFN in combination with ribavirin has been the standard of care (SOC for chronic hepatitis C for the past few decades. Although the current SOC lacks the desired efficacy, and 4 new direct-acting antiviral agents have been recently approved, interferons are still likely to remain the cornerstone of therapy for some time. Moreover, as an important cytokine system of innate immunity, host interferon signaling provides a powerful antiviral response. Nevertheless, the mechanisms by which HCV infection controls interferon production, and how interferons, in turn, trigger anti-HCV activities as well as control the outcome of HCV infection remain to be clarified. In this report, we review current progress in understanding the mechanisms of IFN against HCV, and also summarize the knowledge of induction of interferon signaling by HCV infection.

  15. Addressing HCV infection in Europe: reported, estimated and undiagnosed cases

    DEFF Research Database (Denmark)

    Merkinaite, Simona; Lazarus, Jeff; Gore, Charles

    2008-01-01

    The hepatitis C virus (HCV) is a major public health problem due to its high prevalence, high rate of onward transmission and health complications. As many as 85% of people infected with HCV may go on to become chronic carriers of the disease with the risk of developing liver cancer or cirrhosis....... At present, it is the most common cause of chronic liver disease and liver transplantation in a number of countries, with an estimated 250,000 people dying annually from HCV-related causes. Despite the magnitude of the problem, the virus does not receive adequate attention from either the general public...... cirrhosis and liver cancer. Additionally, as previous studies in central and eastern Europe show, evidence-based measures to prevent and manage HCV among IDUs, where most current transmission is concentrated, remain limited. Therefore, there is a strong need for intensified advocacy to put HCV higher...

  16. The HCV Synthesis Project: Scope, methodology, and preliminary results

    Directory of Open Access Journals (Sweden)

    Scheinmann Roberta

    2008-09-01

    Full Text Available Abstract Background The hepatitis C virus (HCV is hyper-endemic in injecting drug users. There is also excess HCV among non-injection drug users who smoke, snort, or sniff heroin, cocaine, crack, or methamphetamine. Methods To summarize the research literature on HCV in drug users and identify gaps in knowledge, we conducted a synthesis of the relevant research carried out between 1989 and 2006. Using rigorous search methods, we identified and extracted data from published and unpublished reports of HCV among drug users. We designed a quality assurance system to ensure accuracy and consistency in all phases of the project. We also created a set of items to assess study design quality in each of the reports we included. Results We identified 629 reports containing HCV prevalence rates, incidence rates and/or genotype distribution among injecting or non-injecting drug user populations published between January 1989 and December 2006. The majority of reports were from Western Europe (41%, North America (26%, Asia (11% and Australia/New Zealand (10%. We also identified reports from Eastern Europe, South America, the Middle East, and the Caribbean. The number of publications reporting HCV rates in drug users increased dramatically between 1989 and 2006 to 27–52 reports per year after 1998. Conclusion The data collection and quality assurance phases of the HCV Synthesis Project have been completed. Recommendations for future research on HCV in drug users have come out of our data collection phase. Future research reports can enhance their contributions to our understanding of HCV etiology by clearly defining their drug user participants with respect to type of drug and route of administration. Further, the use of standard reporting methods for risk factors would enable data to be combined across a larger set of studies; this is especially important for HCV seroconversion studies which suffer from small sample sizes and low power to examine risk

  17. Activity Assays for Rhomboid Proteases.

    Science.gov (United States)

    Arutyunova, E; Strisovsky, K; Lemieux, M J

    2017-01-01

    Rhomboids are ubiquitous intramembrane serine proteases that are involved in various signaling pathways. This fascinating class of proteases harbors an active site buried within the lipid milieu. High-resolution structures of the Escherichia coli rhomboid GlpG with various inhibitors revealed the catalytic mechanism for rhomboid-mediated proteolysis; however, a quantitative characterization was lacking. Assessing an enzyme's catalytic parameters is important for understanding the details of its proteolytic reaction and regulatory mechanisms. To assay rhomboid protease activity, many challenges exist such as the lipid environment and lack of known substrates. Here, we summarize various enzymatic assays developed over the last decade to study rhomboid protease activity. We present detailed protocols for gel-shift and FRET-based assays, and calculation of KM and Vmax to measure catalytic parameters, using detergent solubilized rhomboids with TatA, the only known substrate for bacterial rhomboids, and the model substrate fluorescently labeled casein. © 2017 Elsevier Inc. All rights reserved.

  18. High rate of hepatitis C virus (HCV) recurrence in HIV-infected individuals with spontaneous HCV RNA clearance

    DEFF Research Database (Denmark)

    Peters, L; Mocroft, A; Soriano, V

    2014-01-01

    OBJECTIVES: Following resolution of hepatitis C virus (HCV) infection, recurrence has been shown to occur in some persons with repeated exposure to HCV. We aimed to investigate the rate and factors associated with HCV RNA recurrence among HIV-1-infected patients with prior spontaneous HCV RNA...... clearance in the EuroSIDA cohort. METHODS: All HIV-infected patients with documented prior spontaneous HCV clearance, and at least one subsequently collected plasma sample, were examined. The last sample was tested for HCV RNA and those with HCV RNA ≥ 615 IU/mL were defined as having HCV recurrence...... (IDUs). The median time between the first and last samples was 3.6 years (interquartile range 2.0-5.8 years). After adjustment, those on combination antiretroviral therapy [odds ratio (OR) 0.44; 95% CI 0.20-0.99; P = 0.046] and older persons (OR 0.51 per 10 years older; 95% CI 0.28-0.95; P = 0.033) were...

  19. Protease inhibitors and beyond.

    Science.gov (United States)

    1997-03-01

    A new generation of protease inhibitors is entering studies. Abbott Lab's ABT-378 and Pharmacia/Upjohn's PNU-140690 are beginning clinical studies and both are designed to overcome resistance problems. Several companies are developing new compounds to inhibit reverse transcriptase, such as Bristol-Myers Squibb's lobucavir and Hoechst/Bayer's HBY097. Calanolide A, which will soon begin trials, has a different resistance pattern than other non-nucleoside reverse transcriptase inhibitors, which may be an important advantage. Several groups are developing compounds to inhibit the HIV zinc finger, such as Parke-Davis' compound, CI-1012; and a Dutch company who is developing Azodicarbonamide, a drug currently in phase I/II trials for people with advanced disease in Europe. HIV drugs to date have not been successful in blocking viral fusion. However, three new fusion inhibitors are showing promise within the laboratory: Pentafuside (currently in phase I trials), Fuji ImmunoPharmaceuticals' FP-21399 (currently in phase I trials), and ISIS Pharmaceuticals' ISIS 5320. A new class of drugs known as integrase inhibitors has been of interest to pharmaceutical companies for the past several years; only one drug, Aronex Pharmaceuticals' Zintevir, has reached phase I/II trials.

  20. HCV subtype characterization among injection drug users: implication for a crucial role of Zhenjiang in HCV transmission in China.

    Directory of Open Access Journals (Sweden)

    Chiyu Zhang

    Full Text Available BACKGROUND: HCV transmission is closely associated with drug-trafficking routes in China. However, the transmission route of HCV in Eastern China remains unclear. Here, we investigate the role of Zhenjiang city of Jiangsu province, an important transportation hub linking Shanghai with other regions of China, in HCV transmission. METHODOLOGY/PRINCIPAL FINDINGS: A total of 141 whole blood samples were collected from injection drug users (IDUs in Zhenjiang and then tested for HCV infection. Of them, 115 HCV positive plasmas were subjected to RNA extraction, RT-PCR amplification, and sequencing. The subtype characterization and the evolutionary origin of HCV strains circulating in Zhenjiang were determined using polygenetic or phylogeographic analyses. Seven HCV subtypes 1b, 2a, 3a, 3b, 6a, 6e and 6n were detected among Zhenjiang IDUs, showing a complex HCV epidemic. The most predominant subtypes were 3a (38% and 1b (26.8%. Among these subtypes, subtypes 3b, 6n and 6e originated from Southwestern China (i.e., Yunnan and/or Guangxi, subtypes 2a and 6a from Southern China (i.e., Guangdong, subtype 1b from Central (i.e., Henan and Northwestern (i.e., Xinjiang China, and subtype 3a from Southwestern (i.e., Yunnan and Northwestern (i.e., Xinjiang China. From Zhenjiang, subtypes 1b and 2a were further spread to Eastern (i.e., Shanghai and Northern (i.e., Beijing China, respectively. CONCLUSIONS/SIGNIFICANCE: The mixing of seven HCV subtypes in Zhenjiang from all quarters of China indicates that as an important middle station, Zhenjiang plays a crucial role in HCV transmission, just as it is important in population migration between other regions of China and Eastern China.

  1. Performance of ARCHITECT HCV core antigen test with specimens from US plasma donors and injecting drug users.

    Science.gov (United States)

    Mixson-Hayden, Tonya; Dawson, George J; Teshale, Eyasu; Le, Thao; Cheng, Kevin; Drobeniuc, Jan; Ward, John; Kamili, Saleem

    2015-05-01

    Hepatitis C virus (HCV) core antigen is a serological marker of current HCV infection. The aim of this study was mainly to evaluate the performance characteristics of the ARCHITECT HCV core antigen assay with specimens from US plasma donors and injecting drug users. A total of 551 serum and plasma samples with known anti-HCV and HCV RNA status were tested for HCV core antigen using the Abbott ARCHITECT HCV core antigen test. HCV core antigen was detectable in 100% of US plasma donor samples collected during the pre-seroconversion phase of infection (anti-HCV negative/HCV RNA positive). Overall sensitivity of the HCV core antigen assay was 88.9-94.3% in samples collected after seroconversion. The correlation between HCV core antigen and HCV RNA titers was 0.959. HCV core antigen testing may be reliably used to identify current HCV infection. Published by Elsevier B.V.

  2. Evolving strategy for HCV testing in an Italian tertiary care hospital.

    Science.gov (United States)

    Medici, Maria Cristina; Chezzi, Carlo; De Conto, Flora; Ferraglia, Francesca; Pinardi, Federica; Arcangeletti, Maria Cristina; Bernasconi, Daniela; Galli, Claudio; Calderaro, Adriana

    2016-04-01

    Diagnostic tests for hepatitis C virus (HCV) infection should be adapted according to the clinical status of the patient. We exploited the application of different HCV diagnostic algorithms in a tertiary care hospital practice. The laboratory clinical reports to the medical orders for HCV testing during three years were clustered by different combinations of assays for anti-HCV antibodies (HCV Ab) (screening and confirmatory), HCV nucleic acid (HCV-RNA), HCV core antigen (HCV Ag). The latter was the first-line assay in acute HCV infections requiring a rapid assessment of the infectious state. The majority (91.9%) of the 2726 subjects whose samples were analyzed were inpatients. Most of the patients/subjects were tested for clinical suspicion of viral hepatitis (49.2%), or occupational accident to health care professionals (20.0%). On 66% of samples HCV Ag test alone was performed and resulted positive in 116 cases (6%), while it was detected in 50.3% of anti-HCV positive samples. The agreement between HCV Ag and HCV-RNA was very high (k=0.97); HCV Ag positivity rates increased according to the signal of the HCV Ab screening test. The use of different testing strategies according to the patients' history and clinical status allowed a significant reduction of the number of tests performed and the time needed to provide a diagnostic response useful for patients' management without compromising the overall diagnostic accuracy for HCV infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Claudin-6 and Occludin Natural Variants Found in a Patient Highly Exposed but Not Infected with Hepatitis C Virus (HCV Do Not Confer HCV Resistance In Vitro.

    Directory of Open Access Journals (Sweden)

    Lucie Fénéant

    Full Text Available The clinical course of Hepatitis C Virus (HCV infection is highly variable between infected individual hosts: up to 80% of acutely HCV infected patients develop a chronic infection while 20% clear infection spontaneously. Spontaneous clearance of HCV infection can be predicted by several factors, including symptomatic acute infection, favorable IFNL3 polymorphisms and gender. In our study, we explored the possibility that variants in HCV cell entry factors might be involved in resistance to HCV infection. In a same case patient highly exposed but not infected by HCV, we previously identified one mutation in claudin-6 (CLDN6 and a rare variant in occludin (OCLN, two tight junction proteins involved in HCV entry into hepatocytes. Here, we conducted an extensive functional study to characterize the ability of these two natural variants to prevent HCV entry. We used lentiviral vectors to express Wildtype or mutated CLDN6 and OCLN in different cell lines and primary human hepatocytes. HCV infection was then investigated using cell culture produced HCV particles (HCVcc as well as HCV pseudoparticles (HCVpp expressing envelope proteins from different genotypes. Our results show that variants of CLDN6 and OCLN expressed separately or in combination did not affect HCV infection nor cell-to-cell transmission. Hence, our study highlights the complexity of HCV resistance mechanisms supporting the fact that this process probably not primarily involves HCV entry factors and that other unknown host factors may be implicated.

  4. Claudin-6 and Occludin Natural Variants Found in a Patient Highly Exposed but Not Infected with Hepatitis C Virus (HCV) Do Not Confer HCV Resistance In Vitro.

    Science.gov (United States)

    Fénéant, Lucie; Ghosn, Jade; Fouquet, Baptiste; Helle, François; Belouzard, Sandrine; Vausselin, Thibaut; Séron, Karin; Delfraissy, Jean-François; Dubuisson, Jean; Misrahi, Micheline; Cocquerel, Laurence

    2015-01-01

    The clinical course of Hepatitis C Virus (HCV) infection is highly variable between infected individual hosts: up to 80% of acutely HCV infected patients develop a chronic infection while 20% clear infection spontaneously. Spontaneous clearance of HCV infection can be predicted by several factors, including symptomatic acute infection, favorable IFNL3 polymorphisms and gender. In our study, we explored the possibility that variants in HCV cell entry factors might be involved in resistance to HCV infection. In a same case patient highly exposed but not infected by HCV, we previously identified one mutation in claudin-6 (CLDN6) and a rare variant in occludin (OCLN), two tight junction proteins involved in HCV entry into hepatocytes. Here, we conducted an extensive functional study to characterize the ability of these two natural variants to prevent HCV entry. We used lentiviral vectors to express Wildtype or mutated CLDN6 and OCLN in different cell lines and primary human hepatocytes. HCV infection was then investigated using cell culture produced HCV particles (HCVcc) as well as HCV pseudoparticles (HCVpp) expressing envelope proteins from different genotypes. Our results show that variants of CLDN6 and OCLN expressed separately or in combination did not affect HCV infection nor cell-to-cell transmission. Hence, our study highlights the complexity of HCV resistance mechanisms supporting the fact that this process probably not primarily involves HCV entry factors and that other unknown host factors may be implicated.

  5. Identification of Variants of Hepatitis C Virus (HCV) Entry Factors in Patients Highly Exposed to HCV but Remaining Uninfected: An ANRS Case-Control Study.

    Science.gov (United States)

    Fouquet, Baptiste; Ghosn, Jade; Quertainmont, Yann; Salmon, Dominique; Rioux, Christophe; Duvivier, Claudine; Delfraissy, Jean-François; Misrahi, Micheline

    2015-01-01

    Hepatitis C virus (HCV) causes persistent infection in 75% of cases and is a major public health problem worldwide. More than 92% of intravenous drug users (IDU) infected by human immunodeficiency virus type 1 (HIV-1) are seropositive for HCV, and it is conceivable that some HIV-1-infected IDU who remain uninfected by HCV may be genetically resistant.Here we conducted a case-control study to identify mutations in HCV entry coreceptors in HIV-infected IDU who remained uninfected by HCV. We recruited 138 patients, comprising 22 HIV+ HCV- case IDU and 116 HIV+ HCV+ control IDU. We focused on coreceptors in which point mutations are known to abolish HCV infectivity in vitro. Our previous study of the Claudin-1 gene revealed no specific variants in the same case population. Here we performed direct genomic sequencing of the Claudin-6, Claudin-9, Occludin and Scavenger receptor-B1 (SCARB1) gene coding regions. Most HIV+ HCV- IDU had no mutations in HCV coreceptors. However, two HIV+ HCV- patients harbored a total of four specific mutations/variants of HCV entry factors that were not found in the HIV+ HCV+ controls. One case patient harbored heterozygous variants of both Claudin-6 and Occludin, and the other case patient harbored two heterozygous variants of SCARB1. This suggests that HCV resistance might involve complex genetic events and factors other than coreceptors, a situation similar to that reported for HIV-1 resistance.

  6. Identification of Variants of Hepatitis C Virus (HCV Entry Factors in Patients Highly Exposed to HCV but Remaining Uninfected: An ANRS Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Baptiste Fouquet

    Full Text Available Hepatitis C virus (HCV causes persistent infection in 75% of cases and is a major public health problem worldwide. More than 92% of intravenous drug users (IDU infected by human immunodeficiency virus type 1 (HIV-1 are seropositive for HCV, and it is conceivable that some HIV-1-infected IDU who remain uninfected by HCV may be genetically resistant.Here we conducted a case-control study to identify mutations in HCV entry coreceptors in HIV-infected IDU who remained uninfected by HCV. We recruited 138 patients, comprising 22 HIV+ HCV- case IDU and 116 HIV+ HCV+ control IDU. We focused on coreceptors in which point mutations are known to abolish HCV infectivity in vitro. Our previous study of the Claudin-1 gene revealed no specific variants in the same case population. Here we performed direct genomic sequencing of the Claudin-6, Claudin-9, Occludin and Scavenger receptor-B1 (SCARB1 gene coding regions. Most HIV+ HCV- IDU had no mutations in HCV coreceptors. However, two HIV+ HCV- patients harbored a total of four specific mutations/variants of HCV entry factors that were not found in the HIV+ HCV+ controls. One case patient harbored heterozygous variants of both Claudin-6 and Occludin, and the other case patient harbored two heterozygous variants of SCARB1. This suggests that HCV resistance might involve complex genetic events and factors other than coreceptors, a situation similar to that reported for HIV-1 resistance.

  7. Acetaminophen-induced acute liver injury in HCV transgenic mice

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Takeki; Kosyk, Oksana; Jeannot, Emmanuelle; Bradford, Blair U. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States); Tech, Katherine; Macdonald, Jeffrey M. [Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States); Boorman, Gary A. [Covance, Chantilly, VA 20151 (United States); Chatterjee, Saurabh; Mason, Ronald P. [Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, RTP, NC 27713 (United States); Melnyk, Stepan B. [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72201 (United States); Tryndyak, Volodymyr P.; Pogribny, Igor P. [Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079 (United States); Rusyn, Ivan, E-mail: iir@unc.edu [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States)

    2013-01-15

    The exact etiology of clinical cases of acute liver failure is difficult to ascertain and it is likely that various co-morbidity factors play a role. For example, epidemiological evidence suggests that coexistent hepatitis C virus (HCV) infection increased the risk of acetaminophen-induced acute liver injury, and was associated with an increased risk of progression to acute liver failure. However, little is known about possible mechanisms of enhanced acetaminophen hepatotoxicity in HCV-infected subjects. In this study, we tested a hypothesis that HCV-Tg mice may be more susceptible to acetaminophen hepatotoxicity, and also evaluated the mechanisms of acetaminophen-induced liver damage in wild type and HCV-Tg mice expressing core, E1 and E2 proteins. Male mice were treated with a single dose of acetaminophen (300 or 500 mg/kg in fed animals; or 200 mg/kg in fasted animals; i.g.) and liver and serum endpoints were evaluated at 4 and 24 h after dosing. Our results suggest that in fed mice, liver toxicity in HCV-Tg mice is not markedly exaggerated as compared to the wild-type mice. In fasted mice, greater liver injury was observed in HCV-Tg mice. In fed mice dosed with 300 mg/kg acetaminophen, we observed that liver mitochondria in HCV-Tg mice exhibited signs of dysfunction showing the potential mechanism for increased susceptibility. -- Highlights: ► Acetaminophen-induced liver injury is a significant clinical challenge. ► HCV-infected subjects may be at higher risk for acetaminophen-induced liver injury. ► We used HCV transgenics to test if liver injury due to acetaminophen is exacerbated.

  8. Presence of hepatitis C virus (HCV)-RNA in peripheral blood mononuclear cells in HCV serum negative patients during interferon and ribavirin therapy.

    Science.gov (United States)

    Januszkiewicz-Lewandowska, Danuta; Wysocki, Jacek; Pernak, Monika; Nowicka, Karina; Zawada, Mariola; Rembowska, Jolanta; Lewandowski, Krzysztof; Mańkowski, Przemysław; Nowak, Jerzy

    2007-02-01

    Identification of hepatitis C virus (HCV)-RNA in blood serum is crucial for hepatitis C diagnosis and for appropriate treatment. Detection of HCV-RNA in blood serum is used for therapy monitoring of patients with hepatitis C. Despite HCV-RNA elimination from blood serum during treatment in some patients, HCV viremia appears again after the completion of therapy. The aim of this study was to assess HCV-RNA in peripheral blood mononuclear cells (PBMCs) of hepatitis C patients in relation to HCV-RNA and antibodies to HCV in the serum. The study involved 71 patients undergoing anti-viral therapy (interferon and ribavirin). RNA isolated from serum and PBMCs was examined for the presence of HCV-RNA by an RT-PCR technique using specific oligonucleotide primers or by commercially available kits. In order to show the possible presence of HCV sequences in PBMCs, molecular DNA probes were constructed with a PCR amplicon and biotin-labelled by nick translation, and FISH and extended chromatin fibers in situ hybridization (ECFs-FISH) techniques were used. A 24-month follow-up study revealed that 34 out of 59 patients (58%) eliminated HCV-RNA from their sera. In the serum negative group, HCV-RNA was detected in PBMCs of 2 patients. The presence of HCV-RNA in PBMCs was confirmed by the FISH technique. In the ECFs-FISH procedure, no signal was found in all examined patients. Our data suggest that PBMCs infected with HCV can serve as a virus reservoir. HCV-RNA serum negative patients who have HCV-RNA in their leukocytes after completion of anti-viral therapy would be at great risk of hepatitis C recurrence. These HCV-RNA serum negative but PBMCs positive patients would be a potential source of HCV spread.

  9. seroprevalence of hav, hbv, hcv, and hev among acute hepatitis ...

    African Journals Online (AJOL)

    2013-07-30

    00100, Nairobi, J. Ngaira, Jomo Kenyatta. University of ... (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus .... analysis was carried out using SPSS 11.5 computer software.

  10. Treatment with daclatasvir and sofosbuvir for 24 weeks without ribavirin in cirrhotic patients who failed first-generation protease inhibitors.

    Science.gov (United States)

    Boglione, Lucio; Pinna, Simone Mornese; Cardellino, Chiara Simona; De Nicolò, Amedeo; Cusato, Jessica; Carcieri, Chiara; Cariti, Giuseppe; Di Perri, Giovanni; D'Avolio, Antonio

    2017-02-01

    Treatment of patients with chronic hepatitis C who failed the triple therapy with first generation of protease inhibitors is not still defined. The combined use of sofosbuvir (SOF) and daclatasvir (DCV) seems to be promising due to higher genetic barrier, good tolerance and effectiveness. We described the treatment with this drug combination in a real-life cohort of 20 cirrhotic patients with genotype 1 who failed the triple therapy. 18 of them (90%) with Child-Pugh A, 11 (55%) with genotype 1a, 17 (85%) with more than 1 and 8 (40%) with more than 2 previous failed treatment; all patients had at baseline NS3 resistance-associated variants related to triple therapy failure. RBV was not administered due to anemia in previous treatments. The sustained virological response was 100%. Treatment with SOF + DCV without RBV for 24 weeks is safe and effective in cirrhotic patients who failed triple therapy with the first generation of protease inhibitors.

  11. Development of a VLP-based HCV vaccine candidate

    OpenAIRE

    Fernandes, Marina Isabel Ferreira

    2016-01-01

    Tese de mestrado, Biologia Molecular e Genética, Universidade de Lisboa, Faculdade de Ciências, 2016 The Hepatitis C Virus (HCV) infects approximately 3% of the world population, being one of the major causes of liver cirrhosis and hepatocellular carcinoma. The development of safe, effective and affordable prophylactic and therapeutic vaccines against HCV has become an important medical priority; however, there are many obstacles to its development. In recent years, strategies of viral ant...

  12. Ledipasvir and sofosbuvir for untreated HCV genotype 1 infection.

    OpenAIRE

    Afdhal, Nezam; Zeuzem, Stefan; Kwo, Paul Y.; Chojkier, Mario; Gitlin, Norman; Puoti, Massimo; Romero Gomez, Manuel; Zarski, Jean Pierre; Agarwal, Kosh; Buggisch, Peter; Foster, Graham R.; Bräu, Norbert; Buti, Maria; Jacobson, Ira M.; Subramanian, G.Mani

    2014-01-01

    BACKGROUND: In phase 2 studies, treatment with the all-oral combination of the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor ledipasvir resulted in high rates of sustained virologic response among previously untreated patients with hepatitis C virus (HCV) genotype 1 infection. METHODS: We conducted a phase 3, open-label study involving previously untreated patients with chronic HCV genotype 1 infection. Patients were randomly assigned in a 1:1:1:1 ratio to receive ledipasv...

  13. Unsolved Puzzles Surrounding HCV Immunity: Heterologous Immunity Adds Another Dimension

    Science.gov (United States)

    Gupta, Nancy; Li, Wen; Vedi, Satish; Kumar, Rakesh

    2017-01-01

    Chronic infection with hepatitis C virus (HCV) afflicts 3% of the world’s population and can lead to serious and late-stage liver diseases. Developing a vaccine for HCV is challenging because the correlates of protection are uncertain and traditional vaccine approaches do not work. Studies of natural immunity to HCV in humans have resulted in many enigmas. Human beings are not immunologically naïve because they are continually exposed to various environmental microbes and antigens, creating large populations of memory T cells. Heterologous immunity occurs when this pool of memory T cells cross-react against a new pathogen in an individual. Such heterologous immunity could influence the outcome when an individual is infected by a pathogen. We have recently made an unexpected finding that adenoviruses, a common environmental pathogen and an experimental vaccine vector, can induce robust cross-reactive immune responses against multiple antigens of HCV. Our unique finding of previously uncharacterized heterologous immunity against HCV opens new avenues to understand HCV pathogenesis and develop effective vaccines. PMID:28749434

  14. Prediction of HCV vertical transmission: what factors should be optimized using data mining computational analysis.

    Science.gov (United States)

    Elrazek, Abd; Amer, Mohamed; El-Hawary, Bahaa; Salah, Altaher; Bhagavathula, Akshaya S; Alboraie, M; Saab, Samy

    2017-04-01

    Neonates born to hepatitis C virus (HCV)-positive mothers are usually not screened for HCV. Unscreened children may act as active sources for social HCV transmission, and factors contributing for vertical HCV transmitting still remained controversial and needed optimization. We aimed to investigate the factors contributing for vertical HCV transmission in Egypt; the highest HCV prevalence worldwide. We prospectively followed the neonates born to HCV-positive mother in the child-bearing period, to identify mother-to-child transmission (MTCT) factors from January 2015 to March 2016. Data mining computational analysis was used to quantify the findings. Among 3000 randomized pregnant women, prevalence of HCV was 46/3000 (1.53%). HCV vertical transmission was identified in eight neonates (17.39%). Only high viral load identified at 975.000 IU was the predictor risk for MTCT. Hepatitis C virus in pregnancy has substantial risk for vertical HCV transmission: High viral load in HCV-positive women increases the risk of HCV transmission to neonates. Screening pregnant women during early stage of pregnancy and optimizing the HCV viral load in HCV-positive women might prevent vertical HCV transmission to neonates. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Plant cysteine proteases that evoke itch activate protease-activated receptors

    Science.gov (United States)

    Reddy, V.B.; Lerner, E.A.

    2013-01-01

    Background Bromelain, ficin and papain are cysteine proteases from plants that produce itch upon injection into skin. Their mechanism of action has not been considered previously. Objectives To determine the mechanism by which these proteases function. Methods The ability of these proteases to activate protease-activated receptors was determined by ratiometric calcium imaging. Results We show here that bromelain, ficin and papain activate protease-activated receptors 2 and 4. Conclusions Bromelain, ficin and papain function as signalling molecules and activate protease-activated receptors. Activation of these receptors is the likely mechanism by which these proteases evoke itch. PMID:20491769

  16. Partial Purification and Characterization of Extracellular Protease ...

    African Journals Online (AJOL)

    USER

    ABSTRACT: Microbial proteases have wide industrial applications and proteases of the lactic acid bacteria (LAB) ... the food and dairy industry. ..... Sumantha, A., Larroche, C. and Pandey, A. (2006). Microbiology and industrial biotechnology of food-grade proteases: a perspective. Food. Technology and Biotechnology ...

  17. Curcumin derivatives as HIV-1 protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)

    1993-12-31

    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  18. Optimization of alkaline protease production from Pseudomonas ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... A protease producing bacteria was isolated from meat waste contaminated soil and identified as. Pseudomonas ... Key words: Alkaline protease, casein agar, meat waste contaminated soil, Pseudomonas fluorescens. INTRODUCTION ... advent of new frontiers in biotechnology, the spectrum of protease ...

  19. Expression of core antigen of HCV genotype 3a and its evaluation as screening agent for HCV infection in Pakistan

    OpenAIRE

    Yousaf, Muhammad Z; Idrees, Muhammad; Saleem, Zafar; Rehman, Irshad U; Ali, Muhammad

    2011-01-01

    Abstract Background Pakistan is facing a threat from hepatitis C infection which is increasing at an alarming rate throughout the country. More specific and sensitive screening assays are needed to timely and correctly diagnose this infection. Methods After RNA extraction from specimen (HCV-3a), cDNA was synthesized that was used to amplify full length core gene of HCV 3a. After verification through PCR, DNA sequencing and BLAST, a properly oriented positive recombinant plasmid for core gene ...

  20. High awareness of hepatitis C virus (HCV) but limited knowledge of HCV complications among HIV-positive and HIV-negative men who have sex with men

    NARCIS (Netherlands)

    Lambers, Femke A. E.; Prins, Maria; Davidovich, Udi; Stolte, Ineke G.

    2014-01-01

    Hepatitis C virus (HCV) has emerged as a sexually transmitted infection among HIV-positive men who have sex with men (MSM) in high-income countries. Little is reported about HCV awareness among MSM, although this is essential for developing targeted prevention strategies. We, therefore, studied HCV

  1. Spontaneous viral clearance, viral load, and genotype distribution of hepatitis C virus (HCV) in HIV-infected patients with anti-HCV antibodies in Europe

    DEFF Research Database (Denmark)

    Soriano, Vincent; Mocroft, Amanda; Rockstroh, Juergen

    2008-01-01

    BACKGROUND: Variables influencing serum hepatitis C virus (HCV) RNA levels and genotype distribution in individuals with human immunodeficiency virus (HIV) infection are not well known, nor are factors determining spontaneous clearance after exposure to HCV in this population. METHODS: All HCV...

  2. Ongoing risk behavior and the presence of HCV-RNA affect the hepatitis C virus (HCV)-Specific CD4(+) T cell response

    NARCIS (Netherlands)

    van den Berg, Charlotte H S B; Nanlohy, Nening M; van de Laar, Thijs J W; Prins, Maria; van Baarle, Debbie

    The largest population of people at risk for HCV-infection is injecting drug users (DU). We hypothesize that recurrent exposure to HCV, by continuing risk behavior, influences the development of an HCV-specific T-cell response. Therefore, we studied the association between repeated exposure to and

  3. Production of Recombinant Rhomboid Proteases.

    Science.gov (United States)

    Arutyunova, E; Panigrahi, R; Strisovsky, K; Lemieux, M J

    2017-01-01

    Rhomboid proteases are intramembrane enzymes that hydrolyze peptide bonds of transmembrane proteins in the lipid bilayer. They play a variety of roles in key biological events and are linked to several disease states. Over the last decade a great deal of structural and functional knowledge has been generated on this fascinating class of proteases. Both structural and kinetic analyses require milligram amounts of protein, which may be challenging for membrane proteins such as rhomboids. Here, we present a detailed protocol for optimization of expression and purification of three rhomboid proteases from Escherichia coli (ecGlpG), Haemophilus influenzae (hiGlpG), and Providencia stuartii (AarA). We discuss the optimization of expression conditions, such as concentration of inducing agent, induction time, and temperature, as well as purification protocol with precise details for each step. The provided protocol yields 1-2.5mg of rhomboid enzyme per liter of bacterial culture and can assist in structural and functional studies of intramembrane proteases. © 2017 Elsevier Inc. All rights reserved.

  4. Carbohydrase and protease supplementation increased ...

    African Journals Online (AJOL)

    User

    2014-09-15

    Sep 15, 2014 ... Department of Animal and Wildlife Sciences, Faculty of Natural and Agricultural Science ... control birds was 12% higher than that of the positive control, while diets supplemented with single enzyme ... The inclusion of exogenous proteases in maize-soya-based diets increases protein digestion by.

  5. Factor VII-activating protease

    DEFF Research Database (Denmark)

    Ramanathan, Ramshanker; Gram, Jørgen B; Sand, Niels Peter R

    2017-01-01

    : Factor VII-activating protease (FSAP) may regulate development of cardiovascular disease (CVD). We evaluated sex differences in FSAP measures and examined the association between FSAP and coronary artery calcification (CAC) in a middle-aged population. Participants were randomly selected citizens...

  6. Multicentric performance analysis of HCV quantification assays and its potential relevance for HCV treatment.

    Science.gov (United States)

    Wiesmann, F; Naeth, G; Berger, A; Hirsch, H H; Regenass, S; Ross, R S; Sarrazin, C; Wedemeyer, H; Knechten, H; Braun, P

    2016-06-01

    An accurate quantification of low viremic HCV RNA plasma samples has gained importance since the approval of direct acting antivirals and since only one single measurement predicts the necessity of a prolonged or shortened therapy. As reported previously, HCV quantification assays such as Abbott RealTime HCV and Roche COBAS AmpliPrep/COBAS TaqMan HCV version 2 (CTM v2) may vary in sensitivity and precision particularly in low-level viremia. Importantly, substantial variations were previously demonstrated between some of these assays compared to the Roche High Pure System/COBAS TaqMan assay (HPS) reference assay, which was used to establish the clinical decision points in clinical studies. In this study, the reproducibility of assay performances across several laboratories was assessed by analysing quantification results generated by six independent laboratories (3× RealTime, 3× CTM v2) in comparison with one HPS reference laboratory. The 4th WHO Standard was diluted to 100, 25 and 10 IU/ml, and aliquots were tested in triplicates in 5 independent runs by each assay in the different laboratories to assess assay precision and detection rates. In a second approach, 2 clinical samples (GT 1a & GT 1b) were diluted to 100 and 25 IU/ml and tested as described above. While the result range for WHO 100 IU/ml replicates across all laboratories was similar in this analysis, the CVs of each laboratory ranged from 19.3 to 25.6 % for RealTime laboratories and were lower than CVs of CTM v2 laboratories with a range of 26.1-47.3 %, respectively, and also in comparison with the CV of the HPS reference laboratory (34.9 %). At WHO standard dilution of 25 IU/ml, 24 replicates were quantified by RealTime compared to 8 replicates with CTM v2. Results of clinical samples again revealed a higher variation of CTM v2 results as compared to RealTime values. (CVs at 100 IU/ml: RealTime: 13.1-21.0 % and CTM v2: 15.0-32.3 %; CVs at 25 IU/ml: RealTime 17.6-34.9 % and CTM v2 28

  7. Human subtilase SKI-1/S1P is a master regulator of the HCV Lifecycle and a potential host cell target for developing indirect-acting antiviral agents.

    Directory of Open Access Journals (Sweden)

    Andrea D Olmstead

    2012-01-01

    Full Text Available HCV infection is a major risk factor for liver cancer and liver transplantation worldwide. Overstimulation of host lipid metabolism in the liver by HCV-encoded proteins during viral infection creates a favorable environment for virus propagation and pathogenesis. In this study, we hypothesize that targeting cellular enzymes acting as master regulators of lipid homeostasis could represent a powerful approach to developing a novel class of broad-spectrum antivirals against infection associated with human Flaviviridae viruses such as hepatitis C virus (HCV, whose assembly and pathogenesis depend on interaction with lipid droplets (LDs. One such master regulator of cholesterol metabolic pathways is the host subtilisin/kexin-isozyme-1 (SKI-1--or site-1 protease (S1P. SKI-1/S1P plays a critical role in the proteolytic activation of sterol regulatory element binding proteins (SREBPs, which control expression of the key enzymes of cholesterol and fatty-acid biosynthesis. Here we report the development of a SKI-1/S1P-specific protein-based inhibitor and its application to blocking the SREBP signaling cascade. We demonstrate that SKI-1/S1P inhibition effectively blocks HCV from establishing infection in hepatoma cells. The inhibitory mechanism is associated with a dramatic reduction in the abundance of neutral lipids, LDs, and the LD marker: adipose differentiation-related protein (ADRP/perilipin 2. Reduction of LD formation inhibits virus assembly from infected cells. Importantly, we confirm that SKI-1/S1P is a key host factor for HCV infection by using a specific active, site-directed, small-molecule inhibitor of SKI-1/S1P: PF-429242. Our studies identify SKI-1/S1P as both a novel regulator of the HCV lifecycle and as a potential host-directed therapeutic target against HCV infection and liver steatosis. With identification of an increasing number of human viruses that use host LDs for infection, our results suggest that SKI-1/S1P inhibitors may allow

  8. Human subtilase SKI-1/S1P is a master regulator of the HCV Lifecycle and a potential host cell target for developing indirect-acting antiviral agents.

    Science.gov (United States)

    Olmstead, Andrea D; Knecht, Wolfgang; Lazarov, Ina; Dixit, Surjit B; Jean, François

    2012-01-01

    HCV infection is a major risk factor for liver cancer and liver transplantation worldwide. Overstimulation of host lipid metabolism in the liver by HCV-encoded proteins during viral infection creates a favorable environment for virus propagation and pathogenesis. In this study, we hypothesize that targeting cellular enzymes acting as master regulators of lipid homeostasis could represent a powerful approach to developing a novel class of broad-spectrum antivirals against infection associated with human Flaviviridae viruses such as hepatitis C virus (HCV), whose assembly and pathogenesis depend on interaction with lipid droplets (LDs). One such master regulator of cholesterol metabolic pathways is the host subtilisin/kexin-isozyme-1 (SKI-1)--or site-1 protease (S1P). SKI-1/S1P plays a critical role in the proteolytic activation of sterol regulatory element binding proteins (SREBPs), which control expression of the key enzymes of cholesterol and fatty-acid biosynthesis. Here we report the development of a SKI-1/S1P-specific protein-based inhibitor and its application to blocking the SREBP signaling cascade. We demonstrate that SKI-1/S1P inhibition effectively blocks HCV from establishing infection in hepatoma cells. The inhibitory mechanism is associated with a dramatic reduction in the abundance of neutral lipids, LDs, and the LD marker: adipose differentiation-related protein (ADRP)/perilipin 2. Reduction of LD formation inhibits virus assembly from infected cells. Importantly, we confirm that SKI-1/S1P is a key host factor for HCV infection by using a specific active, site-directed, small-molecule inhibitor of SKI-1/S1P: PF-429242. Our studies identify SKI-1/S1P as both a novel regulator of the HCV lifecycle and as a potential host-directed therapeutic target against HCV infection and liver steatosis. With identification of an increasing number of human viruses that use host LDs for infection, our results suggest that SKI-1/S1P inhibitors may allow development of

  9. Stability of hepatitis C virus (HCV) RNA levels among interferon-naïve HIV/HCV-coinfected individuals treated with combination antiretroviral therapy.

    Science.gov (United States)

    Grint, D; Peters, L; Reekie, J; Soriano, V; Kirk, O; Knysz, B; Suetnov, O; Lazzarin, A; Ledergerber, B; Rockstroh, J K; Mocroft, A

    2013-07-01

    Infection with hepatitis C virus (HCV) is a major cause of chronic liver disease. High HCV RNA levels have been associated with poor treatment response. This study aimed to examine the natural history of HCV RNA in chronically HCV/HIV-coinfected individuals. Mixed models were used to analyse the natural history of HCV RNA changes over time in HIV-positive patients with chronic HCV infection. A total of 1541 individuals, predominantly White (91%), male (73%), from southern (35%) and western central Europe (23%) and with HCV genotype 1 (58%), were included in the analysis. The median follow-up time was 5.0 years [interquartile range (IQR) 2.8 to 8.3 years]. Among patients not on combination antiretroviral therapy (cART), HCV RNA levels increased by a mean 27.6% per year [95% confidence interval (CI) 6.1-53.5%; P = 0.0098]. Among patients receiving cART, HCV RNA levels were stable, increasing by a mean 2.6% per year (95% CI -1.1 to 6.5%; P = 0.17). Baseline HCV RNA levels were 25.5% higher (95% CI 8.8 to 39.1%; P = 0.0044) in individuals with HCV genotype 1 compared with HCV genotypes 2, 3 and 4. A 1 log HIV-1 RNA copies/mL increase in HIV RNA was associated with a 10.9% increase (95% CI 2.3 to 20.2%; P = 0.012) in HCV RNA. While HCV RNA levels increased significantly in patients prior to receiving cART, among those treated with cART HCV RNA levels remained stable over time. © 2013 British HIV Association.

  10. Network analyses reveal pervasive functional regulation between proteases in the human protease web.

    Directory of Open Access Journals (Sweden)

    Nikolaus Fortelny

    2014-05-01

    Full Text Available Proteolytic processing is an irreversible posttranslational modification affecting a large portion of the proteome. Protease-cleaved mediators frequently exhibit altered activity, and biological pathways are often regulated by proteolytic processing. Many of these mechanisms have not been appreciated as being protease-dependent, and the potential in unraveling a complex new dimension of biological control is increasingly recognized. Proteases are currently believed to act individually or in isolated cascades. However, conclusive but scattered biochemical evidence indicates broader regulation of proteases by protease and inhibitor interactions. Therefore, to systematically study such interactions, we assembled curated protease cleavage and inhibition data into a global, computational representation, termed the protease web. This revealed that proteases pervasively influence the activity of other proteases directly or by cleaving intermediate proteases or protease inhibitors. The protease web spans four classes of proteases and inhibitors and so links both recently and classically described protease groups and cascades, which can no longer be viewed as operating in isolation in vivo. We demonstrated that this observation, termed reachability, is robust to alterations in the data and will only increase in the future as additional data are added. We further show how subnetworks of the web are operational in 23 different tissues reflecting different phenotypes. We applied our network to develop novel insights into biologically relevant protease interactions using cell-specific proteases of the polymorphonuclear leukocyte as a system. Predictions from the protease web on the activity of matrix metalloproteinase 8 (MMP8 and neutrophil elastase being linked by an inactivating cleavage of serpinA1 by MMP8 were validated and explain perplexing Mmp8-/- versus wild-type polymorphonuclear chemokine cleavages in vivo. Our findings supply systematically

  11.  Daclatasvir plus asunaprevir dual therapy for chronic HCV genotype 1b infection: results of Turkish early access program.

    Science.gov (United States)

    Köklü, Seyfettin; Köksal, Iftihar; Akarca, Ulus Salih; Balkan, Ayhan; Güner, Rahmet; Demirezen, Aylin; Sahin, Memduh; Akhan, Sila; Ozaras, Reşat; Idilman, Ramazan

     Background. Daclatasvir and asunaprevir dual therapy is approved for the treatment of HCV genotype 1b infection in several countries. To evaluate the efficacy and safety of daclatasvir and asunaprevir dual therapy in Turkish patients. Sixty-one patients with HCV genotype 1b were enrolled in the Turkish early access program. Most of the patients were in difficult-to-treat category. Patients were visited at each 4 week throughout the follow-up period. Laboratory findings and adverse events were recorded at each visit. Fifty-seven of 61 enrolled patients completed 24 weeks of treatment. Two patients died as a result of underlying diseases at 12-14th weeks of treatment. Two patients stopped the treatment early as a consequence of virological breakthrough, and 2 patients had viral relapse at the post-treatment follow-up. Overall SVR12 rates were 90% (55/61) and 93.2% (55/59) according to intention-to-treat (ITT) and per protocol (PP) analysis respectively. In ITT analysis, SVR12 was achieved by 93% (13/14) in relapsers, 80% (12/15) in interferon-ineligible patients and 91% (20/22) in previous nonresponder patients. SVR12 rates were 86.5% and 91.4% in patients with cirrhosis according to ITT and PP analysis respectively. SVR12 was 95.8% in non-cirrhosis group in both analysis. Patients with previous protease inhibitor experience had an SVR12 of 87.5%. Common adverse events developed in 28.8% of patients. There were no treatment related severe adverse event or grade-4 laboratory abnormality. Daclatasvir and asunaprevir dual therapy is found to be effective and safe in difficult-to-treat Turkish patients with HCV genotype 1b infection.

  12. Transmission of HCV infection among long-term hospitalized onco-haematological patients.

    Science.gov (United States)

    Januszkiewicz-Lewandowska, D; Wysocki, J; Rembowska, J; Pernak, M; Lewandowski, K; Nowak, T; Nowicka-Kujawska, K; Nowak, J

    2003-02-01

    Hepatitis C virus (HCV) infection is becoming a substantial problem in long-term hospitalized patients. Onco-haematological patients undergoing chemotherapy are especially prone to HCV infection. These patients are usually immunosuppressed and therefore antibodies to HCV are not produced despite the presence of HCV RNA in peripheral blood. The aim of the study was to see how often long-term hospitalized patients acquired HCV infection, and what were the possible sources and routes of virus transmission. The study involved 129 children with lymphoproliferative diseases, 36 patients with solid tumours, and 61 healthcare workers from onco-haematological wards. All were HCV RNA and anti-HCV negative at the time of first hospitalization. During a two and a half-year follow-up study among 165 onco-haematological patients, HCV RNA appeared in 87 in subsequent hospitalizations. The majority of infections were (82/87) were 1a genotype, 2 were 1b, 1 was 1a + 1b and 1 was 1a + 3a. In an attempt to establish the origin of HCV infection, healthcare workers were screened for HCV genotyping. All HCV-infected staff working on wards had the same genotype (1a). None of the staff was infected with 1b genotype. As the most prevalent genotype in Polish blood donors is 1b, HCV infection in onco-haematological patients is most likely due to horizontal transmission, probably involving genotype 1a, and potential horizontal transmission of HCV is implied by the presence of 1a genotype of HCV in saliva and urine of selected patients. Spread of hospital HCV infection among children may be facilitated by micro-injury of the skin and mucosa. Early detection of HCV RNA is important in such immunosuppressed patients, as they are not able to produce anti-HCV antibodies. This may enable the introduction of prophylactic steps to prevent the spread of HCV infection by horizontal transmission. Copyright 2003 The Hospital Infection Society

  13. Dynamics of HCV RNA levels during acute hepatitis C virus infection

    Science.gov (United States)

    Hajarizadeh, Behzad; Grebely, Jason; Applegate, Tanya; Matthews, Gail V; Amin, Janaki; Petoumenos, Kathy; Hellard, Margaret; Rawlinson, William; Lloyd, Andrew; Kaldor, John; Dore, Gregory J

    2014-01-01

    Understanding viral dynamics during acute hepatitis C virus (HCV) infection can provide important insights into immunopathogenesis and guide early treatment. The aim of this study was investigating the dynamics of HCV RNA and alanine transaminase (ALT) levels during recent HCV infection in the Australian Trial in Acute Hepatitis C (ATAHC). ATAHC was a prospective study of the natural history of recently acquired HCV infection. Longitudinal HCV RNA and ALT levels were compared among individuals with ultimately persistent infection and spontaneous clearance outcomes. Among those with HCV persistence (n=104) and HCV clearance (n=30), median HCV RNA (5.2 vs. 4.1 log IU/mL, respectively) and ALT levels (779 vs. 1765 IU/L, respectively) were high during month two following infection, and then declined during months three and four in both groups. Among those with HCV persistence, median HCV RNA was 2.9 log IU/mL during months four, increased to 5.5 log IU/mL during month five, and remained subsequently relatively stable. Among those with HCV clearance, median HCV RNA was undetectable by month five. Median HCV RNA levels were comparable between individuals with HCV persistence and HCV clearance during month three following infection (3.2 vs. 3.5 log IU/mL, respectively; P=0.935), but markedly different during month five (5.5 vs. 1.0 log IU/mL, respectively; P<0.001). In conclusion, dynamics of HCV RNA levels in those with HCV clearance and HCV persistence diverged between months three and five following infection, with the latter time-point being potentially useful for commencing early treatment. PMID:25042465

  14. Antiretroviral Effects on Host Lipoproteins Are Associated With Changes in Hepatitis C Virus (HCV) RNA Levels in Human Immunodeficiency Virus/HCV Coinfected Individuals

    Science.gov (United States)

    Naggie, Susanna; Patel, Keyur; Yang, Lan-Yan; Chow, Shein-Chung; Johnson, Victoria; Guyton, John R.; Muir, Andrew J.; Sulkowski, Mark; Hicks, Charles

    2015-01-01

    We evaluated the impact of antiretroviral-induced dyslipidemia on hepatitis C virus (HCV) biogenesis in human immunodeficiency virus (HIV)/HCV coinfected patients. This study used serum samples from antiretroviral-naive HIV/HCV patients initiating their first regimen as part of AIDS Clinical Trials Group study protocols (A5142, A5202). Initiation of antiretrovirals increased most lipoproteins and apolipoproteins. In the multivariable model, changes in apolipoproteins were associated with changes in log10 HCV RNA from baseline to week-24 of therapy. Off-target lipogenic changes need to be considered in the context of liver and other metabolic disease in HIV/HCV patients. PMID:26110167

  15. [Serologic prevalence of HCV antibodies in health personnel in Peru].

    Science.gov (United States)

    Colichon Yerosh, Alejandro; Figueroa, Rolando; Moreno, Armando; Zumaeta, Eduardo; Ferrandíz, Jorge; Busalleu, Alejandro; Prado, William; Candella, Ricardo; Colichón, Alejandro; Rodriguez, Wilson; Espinoza, Julio; Kianman, Wilfredo; Amaya, Nelly; García Pérez, Segundo A; Tello Rodriguez, José; Valdez, Jesús; Paucar Sotomayor, Héctor; Sanchez, César

    2004-01-01

    In Peru, new cases of asymptomatic HCV infection are reported with certain frequency in patients with or without antecedents of blood transfusion. Although serologic screening has improved notoriously in the last years, there is still a population of polytransfused patients with high HCV risk (e.g. hemodialyzed patients), making up a major reservoir. Based on this premise, we decided to study the risk of the health worker population in Peru as another major HCV risk group. A total of 2,769 health workers from 7 Public Hospitals and 2 Private Hospitals in the City of Lima and from 7 Public Hospitals in 4 major/main cities of Peru (Chiclayo, Trujillo, Arequipa, and Cusco) were studied. All those workers, who due to their area of work had higher contact with blood and/or blood derivatives (Surgery, ICU, Traumatology, Gynecology, Gastroenterology, Hemodialysis and Laboratories-Blood Banks) were studied. The studied population accounts for 30% of the total health worker population in these services. All serums underwent the EIA-3 test (HCV-Cobas-Core, Lab. Roche, USA). The positive results were confirmed by RT-HCV (Ampiclor, Roche). The positive serums were confirmed by PCR and the positive results with high viral load underwent HCV genotyping (AMPICLOR-Roche Diagnostic, IGEN Diagnostic USA). Of the 2,769 health workers studied in Peru, 32 were positive for HCV antibodies (1.16% of the total number). Lima showed a prevalence slightly higher than the provinces: 26 out of 2,112 vs. 6 out of 657, or 1.23% vs. 0.91%, respectively. The higher risk is assumed by professional with higher level of contact with blood: 2 physicians (Hemodialysis), 5 nurses (HD) and Lab-Blood Bank technicians. The physicians and nurses share the same risk. If we segregate Lima from provinces, it can be seen that the highest risk is in Lima (1.34% compared to 1.07% in provinces). There is a major risk in health workers and the figures are slightly above those that were suspected for Peru (between 0

  16. Evaluation of Relationship between Lichen Planus and HCV Antibody

    Directory of Open Access Journals (Sweden)

    Ali Taghavi Zenouz

    2010-03-01

    Full Text Available Background and aims. Lichen planus is a relatively common chronic mucocutaneaous disease with an unknown cause, and is considered a manifestation of cell-mediated immune response. Hepatitis C virus (HCV and its subgroups have been associated with lichen planus in different geographic locations. The present study was undertaken to evaluate the prevalence of HCV antibody in patients with lichen planus in northwest Iran. Materials and methods. This descriptive analytical study included 30 patients with cutaneous lichen planus, 30 patients with oral lichen planus, and 30 healthy individuals as controls. Anti-HCV test was run for all the subjects. Descriptive statistics as well as chi-square test, to compare means in the three study groups, were applied to the data using SPSS 14.0 computer software. Results. Age and sex differences between the groups were not significant. No statistically significant differences were observed in anti-HCV test results between the groups (P = 0.50. Conclusion. No statistically significant relationships were observed between lichen planus and HCV antibody in the studied samples.

  17. HCV-related central and peripheral nervous system demyelinating disorders.

    Science.gov (United States)

    Mariotto, Sara; Ferrari, Sergio; Monaco, Salvatore

    2014-01-01

    Chronic infection with hepatitis C virus (HCV) is associated with a large spectrum of extrahepatic manifestations (EHMs), mostly immunologic/rheumatologic in nature owing to B-cell proliferation and clonal expansion. Neurological complications are thought to be immune-mediated or secondary to invasion of neural tissues by HCV, as postulated in transverse myelitis and encephalopathic forms. Primarily axonal neuropathies, including sensorimotor polyneuropathy, large or small fiber sensory neuropathy, motor polyneuropathy, mononeuritis, mononeuritis multiplex, or overlapping syndrome, represent the most common neurological complications of chronic HCV infection. In addition, a number of peripheral demyelinating disorders are encountered, such as chronic inflammatory demyelinating polyneuropathy, the Lewis-Sumner syndrome, and cryoglobulin-associated polyneuropathy with demyelinating features. The spectrum of demyelinating forms also includes rare cases of iatrogenic central and peripheral nervous system disorders, occurring during treatment with pegylated interferon. Herein, we review HCV-related demyelinating conditions, and disclose the novel observation on the significantly increased frequency of chronic demyelinating neuropathy with anti-myelin-associated glycoprotein antibodies in a cohort of 59 consecutive patients recruited at our institution. We also report a second case of neuromyelitis optica with serum IgG autoantibody against the water channel aquaporin-4. The prompt recognition of these atypical and underestimated complications of HCV infection is of crucial importance in deciding which treatment option a patient should be offered.

  18. Molecular Mechanisms of Liver Fibrosis in HIV/HCV Coinfection

    Directory of Open Access Journals (Sweden)

    Claudio M. Mastroianni

    2014-05-01

    Full Text Available Chronic hepatitis C virus (HCV infection is an important cause of morbidity and mortality in people coinfected with human immunodeficiency virus (HIV. Several studies have shown that HIV infection promotes accelerated HCV hepatic fibrosis progression, even with HIV replication under full antiretroviral control. The pathogenesis of accelerated hepatic fibrosis among HIV/HCV coinfected individuals is complex and multifactorial. The most relevant mechanisms involved include direct viral effects, immune/cytokine dysregulation, altered levels of matrix metalloproteinases and fibrosis biomarkers, increased oxidative stress and hepatocyte apoptosis, HIV-associated gut depletion of CD4 cells, and microbial translocation. In addition, metabolic alterations, heavy alcohol use, as well drug use, may have a potential role in liver disease progression. Understanding the pathophysiology and regulation of liver fibrosis in HIV/HCV co-infection may lead to the development of therapeutic strategies for the management of all patients with ongoing liver disease. In this review, we therefore discuss the evidence and potential molecular mechanisms involved in the accelerated liver fibrosis seen in patients coinfected with HIV and HCV.

  19. HCV-Related Central and Peripheral Nervous System Demyelinating Disorders

    Science.gov (United States)

    Mariotto, Sara; Ferrari, Sergio; Monaco, Salvatore

    2014-01-01

    Chronic infection with hepatitis C virus (HCV) is associated with a large spectrum of extrahepatic manifestations (EHMs), mostly immunologic/rheumatologic in nature owing to B-cell proliferation and clonal expansion. Neurological complications are thought to be immune-mediated or secondary to invasion of neural tissues by HCV, as postulated in transverse myelitis and encephalopathic forms. Primarily axonal neuropathies, including sensorimotor polyneuropathy, large or small fiber sensory neuropathy, motor polyneuropathy, mononeuritis, mononeuritis multiplex, or overlapping syndrome, represent the most common neurological complications of chronic HCV infection. In addition, a number of peripheral demyelinating disorders are encountered, such as chronic inflammatory demyelinating polyneuropathy, the Lewis-Sumner syndrome, and cryoglobulin-associated polyneuropathy with demyelinating features. The spectrum of demyelinating forms also includes rare cases of iatrogenic central and peripheral nervous system disorders, occurring during treatment with pegylated interferon. Herein, we review HCV-related demyelinating conditions, and disclose the novel observation on the significantly increased frequency of chronic demyelinating neuropathy with anti-myelin-associated glycoprotein antibodies in a cohort of 59 consecutive patients recruited at our institution. We also report a second case of neuromyelitis optica with serum IgG autoantibody against the water channel aquaporin-4. The prompt recognition of these atypical and underestimated complications of HCV infection is of crucial importance in deciding which treatment option a patient should be offered. PMID:25198705

  20. [HCV and HBV prevalence in hemodialyzed pediatric patients. Multicenter study].

    Science.gov (United States)

    Cañero-Velasco, M C; Mutti, J E; Gonzalez, J E; Alonso, A; Otegui, L; Adragna, M; Antonuccio, M; Laso, M; Montenegro, M; Repetto, L; Brandi, M; Canepa, J; Baimberg, E

    1998-01-01

    Hemodialized pediatric patients are a risk population for the hepatitis B and C virus infection. The aim of this paper was to study the serum prevalence of HBV and HCV infection in hemodialized children. We study 61 pediatric patients at hemodialisis, 12 on renal transplant, range between 2 and 20 years old (mean: 12.9 years), 23 male and 38 female. The specific anti-HCV IgC were measured by enzyme immunoassay (ELISA Abbott) and confirmed by LIA-TEK (Organon). The anti-HBV were measured by ELISA Abbott and transaminases by cinetic method (ASAT: 29 UI/L and ALT: 33 UI/L). The 19.7% of studied children were HCV (+) and 29.5% were HBV (+), 38.9% of them were HbsAg (+) and 50% anti-HBs (+). The HCV and HBV infection was more elevated in relation to the transfusion number and the hemodilisis time. The elevation of ALT/ASAT activity isn't a right infection index for HCV and HBV in this children.

  1. Role of HCV Core gene of genotype 1a and 3a and host gene Cox-2 in HCV-induced pathogenesis

    Directory of Open Access Journals (Sweden)

    Ahmad Waqar

    2011-04-01

    Full Text Available Abstract Background Hepatitis C virus (HCV Core protein is thought to trigger activation of multiple signaling pathways and play a significant role in the alteration of cellular gene expression responsible for HCV pathogenesis leading to hepatocellular carcinoma (HCC. However, the exact molecular mechanism of HCV genome specific pathogenesis remains unclear. We examined the in vitro effects of HCV Core protein of HCV genotype 3a and 1a on the cellular genes involved in oxidative stress and angiogenesis. We also studied the ability of HCV Core and Cox-2 siRNA either alone or in combination to inhibit viral replication and cell proliferation in HCV serum infected Huh-7 cells. Results Over expression of Core gene of HCV 3a genotype showed stronger effect in regulating RNA and protein levels of Cox-2, iNOS, VEGF, p-Akt as compared to HCV-1a Core in hepatocellular carcinoma cell line Huh-7 accompanied by enhanced PGE2 release and cell proliferation. We also observed higher expression levels of above genes in HCV 3a patient's blood and biopsy samples. Interestingly, the Core and Cox-2-specific siRNAs down regulated the Core 3a-enhanced expression of Cox-2, iNOS, VEGF, p-Akt. Furthermore, the combined siRNA treatment also showed a dramatic reduction in viral titer and expression of these genes in HCV serum-infected Huh-7 cells. Taken together, these results demonstrated a differential response by HCV 3a genotype in HCV-induced pathogenesis, which may be due to Core and host factor Cox-2 individually or in combination. Conclusions Collectively, these studies not only suggest a genotype-specific interaction between key players of HCV pathogenesis but also may represent combined viral and host gene silencing as a potential therapeutic strategy.

  2. HCV and HBV coexist in HBsAg-negative patients with HCV viremia; possibility of coinfection in these patients must be considered in HBV-high endemic area

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1998-01-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers and is highly associated with HBV infection in Korea. It has been suggested that HCV core protein may impair the polymerase activity of HBV in vitro, potentially lowering HBV titre in coinfected patients. The aim of this study was to confirm the coexistence of HBV viremia in HCV infected patients HCC who have apparent HBsAg seronegativity. The serological profiles of HBV and HCV in 616 patients with HCC were analysed and coinfection rate of HBV and HCV investigated. Sera were obtained from 16 patients who were both anti-HCV and HCV RNA positive but HbsAg negative, and tested for HBV BY PCR. As a control group, sera were obtained from 15 patients with HCC and 30 non-A abd non-B chronic hepatitis patients without HCC; both were anti-HCV, HCV-RNA, and HBsAg negative and tested for HBV PCR. Of 616 patients with HCC, 450 (73.1 %) had current HBV infection, 48 (7.8 %) had anti-HCV antibodies, and nine (1.5 %) had viral markers of both HCV abd HBV by serological profiles. Of 27 the patients with HCV viremia and HBsAg seronegativity, 14 (51.9 %) showed HBV viremia by PCR. In contrast, of the 75 patients in the control group who were both HCV PCR negative and HBsAg negative, five (11.1 %) showed HBV viremia by PCR. The PCR for HBV revealed coexistent HBV viremia in HCV viremia patients, despite HBsAg negativity by EIA. In HBV-endemic areas, the possibility of coinfection of HBV in HBsAg-negative patients with HCV viremia should be considered and molecular analysis for HBV-DNA performed. (author). 18 refs., 4 tabs.

  3. Evaluation of a total hepatitis C virus (HCV) core antigen assay for the detection of antigenaemia in anti-HCV positive individuals.

    Science.gov (United States)

    Valcavi, Pierpaolo; Medici, Maria Cristina; Casula, Francesca; Arcangeletti, Maria Cristina; De Conto, Flora; Pinardi, Federica; Calderaro, Adriana; Chezzi, Carlo; Dettori, Giuseppe

    2004-07-01

    A new, sensitive enzyme immunoassay has been developed for detecting and quantifying total hepatitis C virus (HCV) core antigen in anti-HCV positive or negative sera ("trak-C", Ortho Clinical Diagnostics, Raritan, NJ). The purpose of this study was to evaluate the performance of trak-C as an additional laboratory diagnostic marker of viraemia. The performance was compared to HCV-RNA detection in the "screening" of sera from a large heterogeneous population of hospitalised patients and outpatients. Six hundred and eighteen anti-HCV negative sera, 405 anti-HCV positive/HCV-RNA negative sera, 604 anti-HCV positive/HCV-RNA positive sera and 67 anti-HCV negative sera containing antigens or antibodies potentially interfering with the performance of the assay were analysed. Supplemental HCV antibody testing was performed using a commercial strip immunoblot assay. HCV-RNA was investigated using a qualitative commercial assay. A quantitative commercial RT-PCR was used for the analysis of selected samples. Sensitivity and specificity values were 94.7 and 100%, respectively. The latter was also confirmed when anti-HCV negative samples containing potentially interfering antigens/antibodies were examined. Sensitivity below 100% was probably due to an antigenaemia below the detection limit of trak-C. Besides, because 65.6% of HCV-RNA positive/trak-C negative samples presented specific antibodies against all four RIBA antigens, the hypothesis was raised that, in some cases, the dissociation step efficiency could be sub-optimal. In conclusion, trak-C seems suitable for identifying HCV infection on large based populations. It is a rapid to perform, reliable and specific assay that can be adapted to any laboratory setting. Copyright 2004 Wiley-Liss, Inc.

  4. Hepatitis C Virus (HCV) Registry Veterans in VHA Care in 2015, for the Nation, by VISN and by Station

    Data.gov (United States)

    Department of Veterans Affairs — This report describes the number of Hepatitis C Virus (HCV) registry Veterans in VHA care in 2015 based on serologic evidence of HCV infection status (HCV Positive)...

  5. Safety analysis of raltegravir/truvada regimen in HIV/HCV co-infected patients without switchback after HCV treatment

    Directory of Open Access Journals (Sweden)

    Robert Ehret

    2014-11-01

    Full Text Available Introduction: Due to drug-drug interactions of HIV- and HCV-specific antivirals when initiating an HCV-therapy, the antiretroviral therapy (ART often has to be changed. The spectrum of applicable antiretrovirals is small, therefore many patients were switched to raltegravir/truvada (RAL/TVD in our cohort. Due to the relatively low genetic barrier of RAL, this regimen may be endangered to fail, if the NRTI backbone is not fully active because of pre-existing NRTI resistance. We investigated the long-term follow-up and safety of RAL/TVD in co-infected patients after hepatitis C virus (HCV therapy was stopped and the protective antiretroviral effect of interferon ended. Materials and Methods: Twenty patients initiated a direct-acting antiviral (DAA containing HCV therapy (8x faldaprevir, 6x telaprevir, 2x daclatasvir and 4x simeprevir between 11/2011 and 01/2013. Seventeen were switched to RAL/TVD, three patients were not treated before, but started with the regimen. Diagnosis of HIV infection was dated between 1985 and 2010. The HI-viral suppression was monitored retrospectively to date. Results: Thirteen of the twenty patients (65% remained on RAL/TVD after finishing HCV treatment, for seven patients, no data about their ART continuation was available, after HCV therapy had stopped. All remaining thirteen patients showed an HI-viral load below detection limit up to date (for 15 to 22 months, median 20 months. Only for four patients, historic resistance data were available but none showed NRTI mutations. Conclusions: Switch to RAL/TVD as HIV ART due to initiating HCV therapy was safe for the observed small cohort even in long-term follow-up without switchback or a second ART switch. However, resistance data for the cohort was little, showing no NRTI mutations, indicating a relatively safe setting. Since no further data is available, physicians should keep in mind ART history, historical therapy failure and HIV-resistance while switching ART to

  6. Intrahepatic cytokine expression is downregulated during HCV/HIV co-infection.

    Science.gov (United States)

    Blackard, Jason T; Komurian-Pradel, Florence; Perret, Magali; Sodoyer, Mireille; Smeaton, Laura; St Clair, J Benjamin; Chapman, Stacey; Taylor, Lynn E; Paranhos-Baccalà, Glaucia; Chung, Raymond T

    2006-02-01

    HIV co-infection is associated with reduced HCV treatment response rates and accelerated HCV-related liver disease. Cytokines play an important role in regulating hepatic inflammation and fibrogenesis during chronic HCV infection, yet the roles of HIV and/or its therapies on cytokine expression are unknown. Total RNA was extracted from liver biopsies of 12 HCV mono-infected and 14 HCV/HIV co-infected persons. We used real-time PCR to quantify cytokines that contribute to innate and adaptive immune responses, including IFNalpha, IFNgamma, TNFalpha, TGFbeta(1), IL-2, IL-4, IL-8, IL-10, and IL-12p40. Positive- and negative-strand HCV RNA levels were quantified using a molecular beacon approach. Detection of positive-strand HCV RNA was 100% in both groups; negative-strand HCV RNA was detected in four (33%) HCV mono-infected persons and in nine (64%) HCV/HIV co-infected persons. Median strand-specific HCV RNA levels were not significantly different between the two groups. Detection rates of cytokine mRNAs were lower for the HCV/HIV co-infected group compared to the HCV mono-infected group; the detection rates for TNFalpha, IL-8, and IL-10 were statistically significant. Overall, cytokine mRNA quantities were lower for HCV/HIV co-infected compared to HCV mono-infected persons, with the exception of TGFbeta1. These data suggest that a defect in cytokine activation may occur in HCV/HIV co-infected persons that limits efficient clearance of HCV from the liver. Copyright 2005 Wiley-Liss, Inc.

  7. HCV RNA traffic and association with NS5A in living cells

    Energy Technology Data Exchange (ETDEWEB)

    Fiches, Guillaume N.; Eyre, Nicholas S.; Aloia, Amanda L.; Van Der Hoek, Kylie [Department of Molecular and Cellular Biology, Research Centre for Infectious Diseases, University of Adelaide, Adelaide and Centre for Cancer Biology, SA Pathology, Adelaide, SA (Australia); Betz-Stablein, Brigit; Luciani, Fabio [Systems Immunology, School of Medical Sciences, University of New South Wales, Sydney, NSW (Australia); Chopra, Abha [Institute for Immunology and infectious diseases (IIID), Murdoch University, Perth, WA (Australia); Beard, Michael R., E-mail: michael.beard@adelaide.edu.au [Department of Molecular and Cellular Biology, Research Centre for Infectious Diseases, University of Adelaide, Adelaide and Centre for Cancer Biology, SA Pathology, Adelaide, SA (Australia)

    2016-06-15

    The spatiotemporal dynamics of Hepatitis C Virus (HCV) RNA localisation are poorly understood. To address this we engineered HCV genomes harbouring MS2 bacteriophage RNA stem-loops within the 3′-untranslated region to allow tracking of HCV RNA via specific interaction with a MS2-Coat-mCherry fusion protein. Despite the impact of these insertions on viral fitness, live imaging revealed that replication of tagged-HCV genomes induced specific redistribution of the mCherry-tagged-MS2-Coat protein to motile and static foci. Further analysis showed that HCV RNA was associated with NS5A in both static and motile structures while a subset of motile NS5A structures was devoid of HCV RNA. Further investigation of viral RNA traffic with respect to lipid droplets (LDs) revealed HCV RNA-positive structures in close association with LDs. These studies provide new insights into the dynamics of HCV RNA traffic with NS5A and LDs and provide a platform for future investigations of HCV replication and assembly. - Highlights: • HCV can tolerate can bacteriophage MS2 stem-loop insertions within the 3′ UTR. • MS2 stem-loop containing HCV genomes allow for real-time imaging of HCV RNA. • HCV RNA is both static and motile and associates with NS5A and lipid droplets.

  8. Ongoing Transmission of HCV: Should Cesarean Section be Justified? Data Mining Discovery.

    Science.gov (United States)

    Elrazek, Abd; Saab, Samy; Foad, Mahmoud; Elgohary, Elsayed A; Sallam, Mohammad M; Nawara, Abdallah; Ismael, Ali; Morsi, Samar S; Salah, Altaher; Alboraie, Mohamed; Bhagavathula, Akshaya Srikanth; Zayed, Marwa; Elmasry, Hossam; Salem, Tamer Z

    2017-03-01

    Over the past few decades, cesarean section (CS) rates are steadily increasing in most of the middle- and high-income countries. However, most of the pregnant women (particularly undergoing CS) are not screened for hepatitis C virus (HCV); hence, neonates born to HCV-positive mother could be a source of future HCV infection. In this study, the role of the CS and other surgical interventions in HCV transmission in Egypt, the highest endemic country of HCV-4, was investigated. From January to June 2016, a prospective cohort study was conducted among 3,836 pregnant women in both urban and rural areas across Egypt for HCV screening in both mothers and neonates born to HCV-positive mother. All pregnant women were screened during third trimester or just before delivery, neonates born to HCV-positive mothers were evaluated within 24-h postdelivery to record vertical transmission cases. Data mining (DM)-driven computational analysis was used to quantify the findings. Among 3,836 randomized pregnant women, HCV genotype 4 was identified in 80 women (2.08%). Out of 80 HCV-infected women, 18 have experienced surgical intervention (22.5%) and 62 CS (77.5%). HCV vertical transmission was identified in 10 neonates, 10/80 (12.5%). Screening women who had experienced surgical intervention or CS during child bearing period and before pregnancy might prevent HCV mother-to-child transmission (MTCT). CS should be ethically justified to decrease global HCV transmission.

  9. Protease-sensitive synthetic prions.

    Directory of Open Access Journals (Sweden)

    David W Colby

    2010-01-01

    Full Text Available Prions arise when the cellular prion protein (PrP(C undergoes a self-propagating conformational change; the resulting infectious conformer is designated PrP(Sc. Frequently, PrP(Sc is protease-resistant but protease-sensitive (s prions have been isolated in humans and other animals. We report here that protease-sensitive, synthetic prions were generated in vitro during polymerization of recombinant (rec PrP into amyloid fibers. In 22 independent experiments, recPrP amyloid preparations, but not recPrP monomers or oligomers, transmitted disease to transgenic mice (n = 164, denoted Tg9949 mice, that overexpress N-terminally truncated PrP. Tg9949 control mice (n = 174 did not spontaneously generate prions although they were prone to late-onset spontaneous neurological dysfunction. When synthetic prion isolates from infected Tg9949 mice were serially transmitted in the same line of mice, they exhibited sPrP(Sc and caused neurodegeneration. Interestingly, these protease-sensitive prions did not shorten the life span of Tg9949 mice despite causing extensive neurodegeneration. We inoculated three synthetic prion isolates into Tg4053 mice that overexpress full-length PrP; Tg4053 mice are not prone to developing spontaneous neurological dysfunction. The synthetic prion isolates caused disease in 600-750 days in Tg4053 mice, which exhibited sPrP(Sc. These novel synthetic prions demonstrate that conformational changes in wild-type PrP can produce mouse prions composed exclusively of sPrP(Sc.

  10. Occult HCV Infection: The Current State of Knowledge

    Science.gov (United States)

    Rezaee-Zavareh, Mohammad Saeid; Hadi, Reza; Karimi-Sari, Hamidreza; Hossein Khosravi, Mohammad; Ajudani, Reza; Dolatimehr, Fardin; Ramezani-Binabaj, Mahdi; Miri, Seyyed Mohammad; Alavian, Seyed Moayed

    2015-01-01

    Context Occult HCV infection (OCI) is defined as the presence of HCV-RNA in hepatocytes and the absence of HCV in the serum according to usual tests. We aimed to define OCI and provide information about the currently available diagnostic methods. Then we focus on specific groups that are at high risk of OCI and finally investigate immune responses to OCI and the available treatment approaches. Evidence Acquisition PubMed, Scopus and Google Scholar were comprehensively searched with combination of following keywords: “occult”, “hepatitis C virus” and “occult HCV infection”. The definition of OCI, diagnostic methods, specific groups that are at high risk and available treatment approaches were extract from literature. An analysis of available articles on OCI also was done based on Scopus search results. Results OCI has been reported in several high-risk groups, especially in hemodialysis patients and subjects with cryptogenic liver disease. Furthermore, some studies have proposed a specific immune response for OCI in comparison with chronic hepatitis C (CHC). Conclusions With a clinical history of approximately 11 years, occult HCV infection can be considered an occult type of CHC. Evidences suggest that considering OCI in these high-risk groups seems to be necessary. We suggest that alternative diagnostic tests should be applied and that there is a need for the participation of all countries to determine the epidemiology of this type of HCV infection. Additionally, evaluating OCI in blood transfusion centers and in patients who receive large amounts of blood and clotting factors, such as patients with hemophilia, should be performed in future projects. PMID:26734487

  11. Strategies to manage hepatitis C virus (HCV) disease burden

    DEFF Research Database (Denmark)

    Wedemeyer, H; Duberg, A S; Buti, M

    2014-01-01

    and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV-related morbidity and mortality occurs......The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant...

  12. Constrained pattern of viral evolution in acute and early HCV infection limits viral plasticity

    National Research Council Canada - National Science Library

    Pfafferott, Katja; Gaudieri, Silvana; Ulsenheimer, Axel; James, Ian; Heeg, Malte; Nolan, David; John, Mina; Rauch, Andri; Mallal, Simon; Lucas, Andrew; Klenerman, Paul; Diepolder, Helmut M; Lucas, Michaela

    2011-01-01

    .... Most mutations were maintained into the chronic phase of HCV infection (75%). The lack of reversion of adaptations and high proportion of silent substitutions suggests that HCV has structural and functional limitations that constrain evolution...

  13. Structure and mechanism of rhomboid protease.

    Science.gov (United States)

    Ha, Ya; Akiyama, Yoshinori; Xue, Yi

    2013-05-31

    Rhomboid protease was first discovered in Drosophila. Mutation of the fly gene interfered with growth factor signaling and produced a characteristic phenotype of a pointed head skeleton. The name rhomboid has since been widely used to describe a large family of related membrane proteins that have diverse biological functions but share a common catalytic core domain composed of six membrane-spanning segments. Most rhomboid proteases cleave membrane protein substrates near the N terminus of their transmembrane domains. How these proteases function within the confines of the membrane is not completely understood. Recent progress in crystallographic analysis of the Escherichia coli rhomboid protease GlpG in complex with inhibitors has provided new insights into the catalytic mechanism of the protease and its conformational change. Improved biochemical assays have also identified a substrate sequence motif that is specifically recognized by many rhomboid proteases.

  14. Structure and Mechanism of Rhomboid Protease*

    Science.gov (United States)

    Ha, Ya; Akiyama, Yoshinori; Xue, Yi

    2013-01-01

    Rhomboid protease was first discovered in Drosophila. Mutation of the fly gene interfered with growth factor signaling and produced a characteristic phenotype of a pointed head skeleton. The name rhomboid has since been widely used to describe a large family of related membrane proteins that have diverse biological functions but share a common catalytic core domain composed of six membrane-spanning segments. Most rhomboid proteases cleave membrane protein substrates near the N terminus of their transmembrane domains. How these proteases function within the confines of the membrane is not completely understood. Recent progress in crystallographic analysis of the Escherichia coli rhomboid protease GlpG in complex with inhibitors has provided new insights into the catalytic mechanism of the protease and its conformational change. Improved biochemical assays have also identified a substrate sequence motif that is specifically recognized by many rhomboid proteases. PMID:23585569

  15. The negative impact of HBV/HCV coinfection on cirrhosis and its consequences.

    Science.gov (United States)

    Pol, S; Haour, G; Fontaine, H; Dorival, C; Petrov-Sanchez, V; Bourliere, M; Capeau, J; Carrieri, P; Larrey, D; Larsen, C; Marcellin, P; Pawlostky, J-M; Nahon, P; Zoulim, F; Cacoub, P; de Ledinghen, V; Mathurin, P; Negro, F; Pageaux, G-P; Yazdanpanah, Y; Wittkop, L; Zarski, J-P; Carrat, F

    2017-10-09

    Hepatitis B virus (HBV)/hepatitis C virus (HCV) confection has been rarely studied in nonasian series. To compare the characteristics of HBV/HCV coinfected patients to those of HBV- or HCV-monoinfected patients in the ANRS CO22 HEPATHER cohort study. Of the 20 936 included patients, 95 had HBV/HCV coinfection (hepatitis B surface antigen, anti-HCV antibody and HCV RNA positive) and were matched with 375 HBV- and 380 HCV-monoinfected patients on age, gender and time since HBV or HCV diagnosis. F3-F4 fibrosis was more frequent in coinfected patients (58%) than in HBV- (32%, P HBV- (2%, P = .0002) or HCV- (4%, P = .0275) monoinfected patients. Past excessive alcohol use was more frequent in coinfected patients (26%) than in HBV (12%, P = .0011), but similar in HCV monoinfected patients (32%, P = .2868). Coinfected patients had a higher proportion with arterial hypertension (42%) than HBV- (26%) or HCV-monoinfected patients (25%) (P HBV-infected patients (OR = 3.84, 95% CI 1.99-7.43) and the association between decompensated cirrhosis and coinfection in HBV infected (OR = 5.58, 95% CI 1.42-22.0) or HCV infected patients (OR = 3.02, 95% CI 1.22-7.44). HCV coinfection harmfully affects liver fibrosis in HBV patients, while decompensated cirrhosis is increased in coinfected patients compared with HBV- or HCV-monoinfected patients. HCV treatment is as safe and effective in coinfected as monoinfected patients and should be considered following the same rules as HCV monoinfected patients. © 2017 John Wiley & Sons Ltd.

  16. Effects of different anti-HIV therapies on progression of hepatitis C in HCV/HIV-coinfected patients

    Directory of Open Access Journals (Sweden)

    SUN Hongqing

    2013-11-01

    Full Text Available ObjectiveTo investigate the effect of protease inhibitors (PIs- or non-nucleoside reverse transcriptase inhibitors (NNRTIs-based therapy on the progression of hepatitis C in patients with hepatitis C virus (HCV/human immunodeficiency virus (HIV coinfection. MethodsA total of 273 patients initially diagnosed with HCV/HIV coinfection were enrolled and divided into PIs group (n=135 and NNRTIs group (n=138 to receive PIs-based therapy and NNRTIs-based therapy, respectively, for one year. Laboratory indices, such as HCV RNA, aspartate aminotransferase (AST, alanine aminotransferase (ALT, total bilirubin (TBil, albumin (Alb, laminin (LN, cholyglycine (CG, type III procollagen (PCIII, type IV collagen (CIV, prothrombin activity (PTA, and cholinesterase (CHE, were quantified before and after treatment. The obtained data were analyzed using SPSS 11.5 software; enumeration data were analyzed using the Kolmogorov-Smirnov test, and non-normal data were analyzed using the Mann-Whitney U test. ResultsAfter the end of treatment, PTA, CHE, TBil, Alb, ALT, AST, CG, and LN levels were significantly higher in NNRTIs group than in PIs [PTA: 77% (67%-109% vs 68% (56%-91%; CHE: 6717.00 U/L (5951.00-7622.00 U/L vs 586200 U/L (4392.00-8539.25 U/L; TBil: 10.95 μmol/L (8.10-14.32 μmol/L vs 8.60 μmol/L (8.00-9.50 μmol/L; Alb: 43.90 mmol/L (39.65-48.20 mmol/L vs 38.90 mmol/L (36.00-45.00 mmol/L; ALT: 52.50 U/L (30.00-93.50 U/L vs 36.20 U/L (30.30-40.40 U/L; AST: 49.00 U/L (33.00-80.00 U/L vs 31.30 U/L (29.70-38.70 U/L; CG: 16.78 μg/ml (3.26-29.32 μg/ml vs 3.26 μg/ml (102-688 μg/ml; LN: 34.40 ng/ml (16.71-46.54 ng/ml vs 34.05 ng/ml (33.42-64.33 ng/ml; P<0.01 or P<0.05]. ConclusionNNRTIs-based therapy can accelerate the progression of hepatitis C in HCV/HIV-coinfected patients.

  17. Effect of route of delivery on heterologous protection against HCV induced by an adenovirus vector carrying HCV structural genes

    Directory of Open Access Journals (Sweden)

    Guan Jie

    2011-11-01

    Full Text Available Abstract Background An effective vaccine and new therapeutic methods for hepatitis C virus (HCV are needed, and a potent HCV vaccine must induce robust and sustained cellular-mediated immunity (CMI. Research has indicated that adenoviral and vaccinia vectors may have the ability to elicit strong B and T cell immune responses to target antigens. Results A recombinant replication-defective adenovirus serotype 5 (rAd5 vector, rAd5-CE1E2, and a recombinant Tian Tan vaccinia vector, rTTV-CE1E2, were constructed to express the HCV CE1E2 gene (1-746 amino acid HCV 1b subtype. Mice were prime-immunised with rAd5-CE1E2 delivered via intramuscular injection (i.m., intranasal injection (i.n., or intradermal injection (i.d. and boosted using a different combination of injection routes. CMI was evaluated via IFN-γ ELISPOT and ICS 2 weeks after immunisation, or 16 weeks after boost for long-term responses. The humoral response was analysed by ELISA. With the exception of priming by i.n. injection, a robust CMI response against multiple HCV antigens (core, E1, E2 was elicited and remained at a high level for a long period (16 weeks post-vaccination in mice. However, i.n. priming elicited the highest anti-core antibody levels. Priming with i.d. rAd5-CE1E2 and boosting with i.d. rTTV-CE1E2 carried out simultaneously enhanced CMI and the humoral immune response, compared to the homologous rAd5-CE1E2 immune groups. All regimens demonstrated equivalent cross-protective potency in a heterologous surrogate challenge assay based on a recombinant HCV (JFH1, 2a vaccinia virus. Conclusions Our data suggest that a rAd5-CE1E2-based HCV vaccine would be capable of eliciting an effective immune response and cross-protection. These findings have important implications for the development of T cell-based HCV vaccine candidates.

  18. Prevalence of Hepatitis C Virus (HCV) in healthy adults and Human ...

    African Journals Online (AJOL)

    The prevalence of HCV infection in Abuja, FCT, Nigeria was determined among healthy adults and HIV infected persons. A total of n=520 apparently healthy HIV negative persons and n=1,200 infected persons were tested for antibodies against HCV by rapid chromatographic immunoassay HCV kit (Acon, ACON ...

  19. 21 CFR 610.47 - Hepatitis C virus (HCV) “lookback” requirements.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Hepatitis C virus (HCV) âlookbackâ requirements... Disease Agents § 610.47 Hepatitis C virus (HCV) “lookback” requirements. (a) If you are an establishment... after a donor tests reactive for evidence of hepatitis C virus (HCV) infection when tested under § 610...

  20. The Association between Female Genital Cutting and Spousal HCV Infection in Egypt

    Directory of Open Access Journals (Sweden)

    Chris R. Kenyon

    2014-01-01

    Full Text Available Objective. To identify the risk factors for HCV infection within married couples in Egypt. Methods. In 2008 Egypt conducted its first nationally representative survey of HCV prevalence. 11126 of the 12780 individuals aged 15–59 year who were sampled agreed to participate and provided information via a questionnaire about demographic and behavioural characteristics and blood for HCV antibody and RNA analysis. We assessed the risk factors for HCV infection in a subsample of 5182 married individuals via multivariate logistic regression. Results. Overall HCV antibody prevalence in the married couples was 18.2% (95% CI, 16.8–19.6. HCV antibody prevalence was higher in the husbands (23.7% than the wives (12.1%; P<0.001. Having a spouse who was infected with HCV was an independent risk factor for HCV infection with odds ratios of 2.1 (95% CI, 1.6–2.9 and 2.2 (95% CI, 1.6–3.1 for women and men, respectively. Husbands whose wives had experienced female genital cutting (FGC had a higher prevalence of HCV and this relationship was driven by a strong association in urban areas. Amongst the women there was no association between FGC and HCV overall but in urban areas only women who had experienced FGC were HCV infected. Conclusions. This study provides additional evidence of the importance of intrafamilial transmission of HCV in Egypt.

  1. Hepatitis C virus (HCV) interaction with astrocytes: nonproductive infection and induction of IL-18.

    Science.gov (United States)

    Liu, Ziqing; Zhao, Fang; He, Johnny J

    2014-06-01

    Hepatitis C virus (HCV) infection causes the central nervous system (CNS) abnormalities in more than 50 % of chronically infected subjects. However, the underlying mechanisms are largely unknown. In this study, we characterized the HCV interactions with astrocytes, one of the putative HCV target cells in the brain. We demonstrated that primary human astrocytes (PHA) were very inefficiently infected by HCV, either in the cell-free form or through cell-cell contact. We then determined the potential restriction steps of HCV infection and replication in these cells. PHA expressed all known HCV receptors but failed to support HCV entry. HCV IRES-mediated RNA translation was functional in PHA and further enhanced by miR122 expression. Nevertheless, PHA did not support HCV replication regardless of miR122 expression. To our great surprise, we found that HCV exposure induced robust IL-18 expression in PHA and exhibited direct neurotoxicity. Taken together, these results showed that astrocytes did not support productive HCV infection and replication, but HCV interactions with astrocytes and neurons alone might be sufficient to cause CNS dysfunction.

  2. Convergent evolution of escape from hepaciviral antagonism in primates.

    Directory of Open Access Journals (Sweden)

    Maulik R Patel

    Full Text Available The ability to mount an interferon response on sensing viral infection is a critical component of mammalian innate immunity. Several viruses directly antagonize viral sensing pathways to block activation of the host immune response. Here, we show that recurrent viral antagonism has shaped the evolution of the host protein MAVS--a crucial component of the viral-sensing pathway in primates. From sequencing and phylogenetic analyses of MAVS from 21 simian primates, we found that MAVS has evolved under strong positive selection. We focused on how this positive selection has shaped MAVS' susceptibility to Hepatitis C virus (HCV. We functionally tested MAVS proteins from diverse primate species for their ability to resist antagonism by HCV, which uses its protease NS3/4A to cleave human MAVS. We found that MAVS from multiple primates are resistant to inhibition by the HCV protease. This resistance maps to single changes within the protease cleavage site in MAVS, which protect MAVS from getting cleaved by the HCV protease. Remarkably, most of these changes have been independently acquired at a single residue 506 that evolved under positive selection. We show that "escape" mutations lower affinity of the NS3 protease for MAVS and allow it to better restrict HCV replication. We further show that NS3 proteases from all other primate hepaciviruses, including the highly divergent GBV-A and GBV-C viruses, are functionally similar to HCV. We conclude that convergent evolution at residue 506 in multiple primates has resulted in escape from antagonism by hepaciviruses. Our study provides a model whereby insights into the ancient history of viral infections in primates can be gained using extant host and virus genes. Our analyses also provide a means by which primates might clear infections by extant hepaciviruses like HCV.

  3. Convergent evolution of escape from hepaciviral antagonism in primates.

    Science.gov (United States)

    Patel, Maulik R; Loo, Yueh-Ming; Horner, Stacy M; Gale, Michael; Malik, Harmit S

    2012-01-01

    The ability to mount an interferon response on sensing viral infection is a critical component of mammalian innate immunity. Several viruses directly antagonize viral sensing pathways to block activation of the host immune response. Here, we show that recurrent viral antagonism has shaped the evolution of the host protein MAVS--a crucial component of the viral-sensing pathway in primates. From sequencing and phylogenetic analyses of MAVS from 21 simian primates, we found that MAVS has evolved under strong positive selection. We focused on how this positive selection has shaped MAVS' susceptibility to Hepatitis C virus (HCV). We functionally tested MAVS proteins from diverse primate species for their ability to resist antagonism by HCV, which uses its protease NS3/4A to cleave human MAVS. We found that MAVS from multiple primates are resistant to inhibition by the HCV protease. This resistance maps to single changes within the protease cleavage site in MAVS, which protect MAVS from getting cleaved by the HCV protease. Remarkably, most of these changes have been independently acquired at a single residue 506 that evolved under positive selection. We show that "escape" mutations lower affinity of the NS3 protease for MAVS and allow it to better restrict HCV replication. We further show that NS3 proteases from all other primate hepaciviruses, including the highly divergent GBV-A and GBV-C viruses, are functionally similar to HCV. We conclude that convergent evolution at residue 506 in multiple primates has resulted in escape from antagonism by hepaciviruses. Our study provides a model whereby insights into the ancient history of viral infections in primates can be gained using extant host and virus genes. Our analyses also provide a means by which primates might clear infections by extant hepaciviruses like HCV.

  4. Bluetongue virus nonstructural protein NS3/NS3a is not essential for virus replication

    NARCIS (Netherlands)

    Gennip, van H.G.P.; Water, van de S.G.P.; Rijn, van P.A.

    2014-01-01

    Orbiviruses form the largest genus of the family Reoviridae consisting of at least 23 different virus species. One of these is the bluetongue virus (BTV) and causes severe hemorrhagic disease in ruminants, and is transmitted by bites of Culicoides midges. BTV is a non-enveloped virus which is

  5. HCV and HBV infections in Nigerian Patients with Liver Cirrhosis ...

    African Journals Online (AJOL)

    The present study is aimed at determining the incidence of HCV and HBV infections in Nigerian patients with Liver Cirrhosis (LC) and Hepatocellular Carcinoma (HCC). The incidence of HBV and antibodies to HVC was determined by Enzyme Linked Immunosorbent Assey (ELISA) in 24 Nigerians with histologically ...

  6. Prevalence of Hepatitis C Virus (HCV) and Human ...

    African Journals Online (AJOL)

    Prevalence of Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV) Co-Infection Among Pregnant Women Attending Antenatal Clinics in Abuja, Nigeria. ... with this virus complicates issues related to diagnosis, clinical disease progression, monitoring disease activity, treatment options and basic immunology.

  7. The Case of anti-HCV Negative Chronic Hepatitis C

    Directory of Open Access Journals (Sweden)

    A. L. Rossina

    2015-01-01

    Full Text Available The paper gives a brief literary reference relating to contemporary aspects of serological diagnosis of hepatitis C, and understands a clinical example of chronic hepatitis C in a child with acute lymphoblastic leukemia, with the absence of circulating antibodies to HCV classes M, and G for almost 2 years.

  8. Phylogenetics of HCV: Recent advances | Bostan | African Journal of ...

    African Journals Online (AJOL)

    Hepatitis C virus (HCV), a virus present in human population from indefinite time period, has affected millions of people globally, by causing liver infection which in majority of cases leads to chronicity, cirrhosis, end stage liver disease and hepatocellular carcinoma (HCC). The disease burden is expected to increase in the ...

  9. Prevalence of HBV and HCV among blood donors in Kosovo

    Science.gov (United States)

    Fejza, Hajrullah; Telaku, Skender

    2009-01-01

    Hepatitis is disease of the liver caused by the infectious and non-infectious agents. The aim of study was to analyze the prevalence of HBV and HCV among voluntary blood donors in Kosovo, during 2000–2003. The data from National Center for Blood Transfusion of Kosovo were collected and analyzed through descriptive and comparative epidemiological method of retrospective study. All samples were tested by ELISA test. Out of 70348 samples of the blood donors, 3145 were positive. From overall positive samples, 2939 were HBV positive, 192 HCV positive while 14 samples were positive for both viruses. The HBV prevalence among the blood donors of Kosovo is 4.2%, which range Kosovo to the second zone according to the CDC classification of the geographical spread of the HBV infection. The HCV prevalence among the blood donors in Kosovo is 0.3%. Compared to the other European countries this level of prevalence is relatively low. Age group 30–39 years old was presented with 34.8% of cases. The higher number was among the workers, 842 or 26.8%. Based on the results we can conclude that Kosovo have the similar prevalence for HBV and HCV infections as other South East European countries. PMID:19216773

  10. Frequencies of HBV, HCV, HIV, and Syphilis Markers Among Blood ...

    African Journals Online (AJOL)

    Purpose: This study aimed to determine the frequency rates of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis among blood donors. Methods: Physically fit persons aged 18 – 48 years who came for blood donation at the blood bank unit of the military hospital in Hodeidah, ...

  11. Glances in Immunology of HIV and HCV Infection

    Science.gov (United States)

    Quaranta, Maria Giovanna; Mattioli, Benedetta; Vella, Stefano

    2012-01-01

    Since the identification of HIV and HCV much progress has been made in the understanding of their life cycle and interaction with the host immune system. Despite these viruses markedly differ in their virological properties and in their pathogenesis, they share many common features in their immune escape and survival strategy. Both viruses have developed sophisticated ways to subvert and antagonize host innate and adaptive immune responses. In the last years, much effort has been done in the study of the AIDS pathogenesis and in the development of efficient treatment strategies, and a fatal infection has been transformed in a potentially chronic pathology. Much of this knowledge is now being transferred in the HCV research field, especially in the development of new drugs, although a big difference still remains between the outcome of the two infections, being HCV eradicable after treatment, whereas HIV eradication remains at present unachievable due to the establishment of reservoirs. In this review, we present current knowledge on innate and adaptive immune recognition and activation during HIV and HCV mono-infections and evasion strategies. We also discuss the genetic associations between components of the immune system, the course of infection, and the outcome of the therapies. PMID:22754568

  12. The Phylogeographic and Spatiotemporal Spread of HCV in Pakistani Population.

    Directory of Open Access Journals (Sweden)

    Noor-Ul-Huda Ghori

    Full Text Available Hepatitis C Virus (HCV is the most prevalent human pathogen in Pakistan and is the major cause of liver cirrhosis and hepatocellular carcinoma in infected patients. It has shifted from being hypo-endemic to being hyper-endemic. There was no information about the origin and evolution of the local variants. Here we use newly developed phyloinformatic methods of sequence analysis to conduct the first comprehensive investigation of the evolutionary and biogeographic history in unprecedented detail and breadth. Considering evolutionary rate and molecular-clock hypothesis in context, we reconstructed the spatiotemporal spread of HCV in the whole territory of its circulation using a combination of Bayesian MCMC methods utilizing all sequences available in GenBank. Comparative analysis were performed and were addressed. Whole genome and individual gene analysis have shown that sub-types 1a, 1b and 3a are recognized as epidemic strains and are distributed globally. Here we confirm that the origin of HCV 3a genotypes is in South Asia and HCV has evolved in the region to become stably adapted to the host environment.

  13. Occult HCV infection: an unexpected finding in a population unselected for hepatic disease.

    Directory of Open Access Journals (Sweden)

    Laura De Marco

    Full Text Available BACKGROUND: Occult Hepatitis C virus (HCV infection is a new pathological entity characterized by presence of liver disease and absence or very low levels of detectable HCV-RNA in serum. Abnormal values of liver enzymes and presence of replicative HCV-RNA in peripheral blood mononuclear cells are also observed. Aim of the study was to evaluate occult HCV occurrence in a population unselected for hepatic disease. METHODOLOGY/PRINCIPAL FINDINGS: We chose from previous epidemiological studies three series of subjects (n = 276, age range 40-65 years unselected for hepatic disease. These subjects were tested for the presence of HCV antibodies and HCV-RNA in plasma and in the peripheral blood mononuclear cells (PBMCs by using commercial systems. All subjects tested negative for HCV antibodies and plasma HCV-RNA and showed normal levels of liver enzymes; 9/276 patients (3.3% were positive for HCV-RNA in PBMCs, identifying a subset of subjects with potential occult HCV infection. We could determine the HCV type for 8 of the 9 patients finding type 1a (3 patients, type 1b (2 patients, and type 2a (3 patients. CONCLUSIONS: The results of this study show evidence that occult HCV infection may occur in a population unselected for hepatic disease. A potential risk of HCV infection spread by subjects harbouring occult HCV infection should be considered. Design of prospective studies focusing on the frequency of infection in the general population and on the clinical evolution of occult HCV infection will be needed to verify this unexpected finding.

  14. Diagnostic reliability of Architect anti-HCV assay: Experience of a tertiary care hospital in India.

    Science.gov (United States)

    Fletcher, Gnanadurai John; Raghavendran, Anantharam; Sivakumar, Jayashree; Samuel, Prasanna; Abraham, Priya

    2017-06-28

    Anti-HCV assays are prone to false positive results. Thus, accurate detection of HCV infection is critical for the timely therapeutic management. This study ascertained the reliability of Architect anti-HCV assay (Abbott) and to estimate the agreement of this assay with Ortho HCV 3.0 ELISA Test System with Enhanced SAVe (Ortho), HCV Tri-dot (Tri-dot) and HCV-PCR in a tertiary care setting. A total of 78 788 consecutive sera were routinely screened for anti-HCV antibodies using Architect. All repeatedly reactive anti-HCV sera (n=1000) and anti-HCV negative sera (n=300) were tested in Ortho and in Tri-dot assays. Representative proportions of sera (n=500) with various signal-to-cut-off (S/Co) ratio were also compared with HCV-PCR. When Architect was compared with Ortho, Tri-dot, and HCV-PCR, the level of agreement as assessed by kappa were .26, .16, and .27 respectively. Using Latent class analysis (LCA), we found that sensitivity and specificity were 100% and 36.1% for Architect, 93.8% and 100% for Ortho and 63.8% and 100% for Tri-dot respectively. The median S/CO ratio of Architect and Ortho anti-HCV assays were significantly different between HCV-PCR positive and negative results (PArchitect S/CO ratio of >8 showed higher accuracy indices in both anti-HCV assays. Architect can be used as a screening assay because of its high sensitivity, high throughput, and short turnaround time. However, S/Co ratios of ≥1 to Architect necessitates HCV PCR to identify current infection and or EIA to distinguish true positivity from false biological positivity. © 2017 Wiley Periodicals, Inc.

  15. Glomerular diseases associated with HBV and HCV infection

    Directory of Open Access Journals (Sweden)

    Boriana Kiperova

    2014-03-01

    Full Text Available Hepatitis B and C viruses are human pathogens of major significance. Their extrahepatic manifestations are global health problem. HBV is a well-known cause of membranous nephropathy, membranoproliferative GN and IgA nephropathy, frequently in Asian populations. Polyarteritis nodosa is a rare, but serious systemic complication of chronic HBV. Immunosuppressive therapy in HBV-related GN is not recommended. Interferon alpha treatment produces sustained remission of porteinuria, often associated with clearance of HBeAg and/or HBsAg, however, it has many side effects. Compared to interferon, nucleos(tide analogues offer some advantages. These antiviral agents suppress HBV replication through their inhibitory effect on viral DNA polymerase. They have convenient administration and high tolerability. Lamivudine is well tolerated and safe in long-term studies, but the resistance of HBV is an escalating problem. The resistance to newer polymerase inhibitors Entecavir and Tenofovir is significantly lower. Hepatitis C virus causes cryoglobulinemia-mediated glomerulonephritis and other immune complex forms of GN. The renal manifestations are usually associated with long-lasting HCV infection. HCV glomerular disease is more frequent in adult males, and often leads to chronic renal insufficiency. The first line treatment in patients with mild to moderate clinical and histological kidney damage is the antiviral therapy with pegylated INF alpha and ribavirin. In case of severe HCV-associated cryoglobulinemic GN - nephrotic syndrome, nephritic syndrome and/or progressive renal failure, high activity score of glomerulonephritis on light microscopy, the initial treatment might consist of sequential administration of antiviral and immunosuppressive agents (corticosteroids, cyclophosphamide and plasma exchange, or rituximab. The treatment of HCV-related glomerular disease is still under debate and based on scant experimental evidence. Large randomized and controlled

  16. High awareness of hepatitis C virus (HCV) but limited knowledge of HCV complications among HIV-positive and HIV-negative men who have sex with men.

    Science.gov (United States)

    Lambers, Femke A E; Prins, Maria; Davidovich, Udi; Stolte, Ineke G

    2014-04-01

    Hepatitis C virus (HCV) has emerged as a sexually transmitted infection among HIV-positive men who have sex with men (MSM) in high-income countries. Little is reported about HCV awareness among MSM, although this is essential for developing targeted prevention strategies. We, therefore, studied HCV awareness and knowledge among HIV-positive and HIV-negative MSM from the Amsterdam Cohort Studies (ACS). During two visits, 1 year apart and starting in October 2007, MSM from the ACS answered questions regarding HCV awareness, knowledge of HCV transmission (7 items), complications (8 items) and sexual risk behaviour. We examined the percentage of HCV awareness and correctly answered knowledge items, and whether awareness and knowledge improved significantly over time. Using logistic regression, we studied whether HIV status and sexual risk behaviour were associated with awareness. Seventy percent (312/444) of HIV-negative and 80% (74/92) of HIV-positive MSM reported to have ever heard of HCV on the first visit. Overall, awareness increased with 9% between the first and second visit (p awareness was borderline significant (OR 1.49, 95% CI 0.97-2.30). Compared with knowledge of transmission routes, knowledge of complications appeared to be limited. In the ACS, awareness of HCV is high, particularly among those reporting group sex, an important risk factor for HCV transmission. The majority of participants had good knowledge of transmission routes, but limited knowledge of complications of chronic HCV infection. HCV prevention messages could be strengthened, therefore, by further addressing the complications of HCV infection.

  17. Ledipasvir and sofosbuvir for HCV infection in patients coinfected with HBV.

    Science.gov (United States)

    Gane, Edward J; Hyland, Robert H; An, Di; Svarovskaia, Evguenia S; Brainard, Diana; McHutchison, John G

    2016-01-01

    Currently there are no all-oral treatment regimens for HCV in patients coinfected with HBV. In this pilot study, we evaluated whether ledipasvir and sofosbuvir therapy can suppress HCV infection in patients coinfected with HBV. Patients with HBV and genotype-1 HCV received 90 mg ledipasvir and 400 mg sofosbuvir daily for 12 weeks. The efficacy end point was sustained virological response (HCV RNA ledipasvir/sofosbuvir was a safe and effective treatment for genotype-1 HCV infection in patients coinfected with HBV. Larger studies with longer follow-up are warranted.

  18. Discovery of fused tricyclic core containing HCV NS5A inhibitors with pan-genotype activity.

    Science.gov (United States)

    Yu, Wensheng; Coburn, Craig A; Yang, De-Yi; Meinke, Peter T; Wong, Michael; Rosenblum, Stuart B; Chen, Kevin X; Njoroge, George F; Chen, Lei; Dwyer, Michael P; Jiang, Yueheng; Nair, Anilkumar G; Selyutin, Oleg; Tong, Ling; Zeng, Qingbei; Zhong, Bin; Ji, Tao; Hu, Bin; Agrawal, Sony; Xia, Ellen; Zhai, Ying; Liu, Rong; Kong, Rong; Ingravallo, Paul; Asante-Appiah, Ernest; Nomeir, Amin; Fells, James; Kozlowski, Joseph A

    2016-07-01

    HCV NS5A inhibitors have demonstrated impressive in vitro potency profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed dose combination regimen for the treatment of HCV infection. Herein, we describe research efforts that led to the discovery of a series of fused tricyclic core containing HCV NS5A inhibitors such as 24, 39, 40, 43, and 44 which have pan-genotype activity and are orally bioavailable in the rat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. HCV - Estimation of the number of diagnosed patients eligible to the new anti-HCV therapies in Italy.

    Science.gov (United States)

    Gardini, I; Bartoli, M; Conforti, M; Mennini, F S; Marcellusi, A; Lanati, E

    2016-12-01

    The present research wants to take a picture of the current epidemiological scenario regarding HCV infection in Italy. Studies used to estimate HCV burden of illness in Italy were so far local and performed a number of years ago, not mirroring the state of the art. EpaC wanted to provide a real number of diagnosed patients, eligible to new anti-HCV therapies. EpaC is the most important Italian NGO for hepatopathic patients. A number of sources were cross-checked. Starting from all regional data regarding HCV-related exemptions, a correction/integration was performed with online questionnaire to associated patients (from which we derived patients cured and also other/no exemptions); survey to all prescribing centers in Italy (from which we derived the percentage of ineligible patients); prevalence of particular subpopulations was also collected (prisoners and HIV/HCV coinfected); calculations of new diagnosed, dead and cured patients in 2015. Excluded patients were illegal immigrants and active drug addicts (subpopulations currently rarely cured). A total of 221,549 patients were derived from regional exemptions databases and the mean national prevalence was 0.364%. Adding patients without exemptions/other exemptions, total was 308,624. We deducted the yearly deaths, cured and not eligible patients and, last, integrated with coinfected and prisoner special groups. Prevalence was also estimated at regional level, highlighting a reduction of the typical North-to-South prevalence gradient. Applying the above-mentioned corrections/integrations, total diagnosed and eligible HCV patients in Italy who can be immediately cured are supposed to range 163,148-187,756. This is a research aimed at filling an informative gap able to provide useful actual information in terms of HCV patients real-life management and future resource allocation. These data may be considered the basis for policy- and decision-makers to plan and manage patients ready to be cured. The research does not

  20. HCV-specific T-cell responses in injecting drug users : evidence for previous exposure to HCV and a role for CD4+ T cells focussing on nonstructural proteins in viral clearance

    NARCIS (Netherlands)

    Ruys, T A; Nanlohy, N M; van den Berg, C H S B; Hassink, E; Beld, M; van de Laar, T; Bruisten, S; Wit, F; Krol, A; Prins, M; Lange, J; van Baarle, D

    In order to understand the parameters associated with resolved hepatitis C virus (HCV)-infection, we analysed the HCV-specific T-cell responses longitudinally in 13 injecting drug-users (IDUs) with a prospectively identified acute HCV infection. Seven IDUs cleared HCV and six IDUs remained

  1. Optimization of medium composition for thermostable protease ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... Optimization of the fermentation medium for maximization of thermostable neutral protease production by Bacillus sp. ... at 3.6 g/l and yeast extract at 3.9 g/l gived maximum protease activity of 6804 U/ml. Key words: Medium ... face method, which is used to study the effects of several factors influencing the ...

  2. Optimization of medium composition for thermostable protease ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... Full Length Research Paper. Optimization of medium composition for thermostable protease production by Bacillus sp. HS08 with a statistical method .... Table 2. Effects of some elements in basic medium on the thermostable protease production. Element. Relatively activity (%). Control. Conc. (g/l). 100.

  3. Partial Purification and Characterization of Extracellular Protease ...

    African Journals Online (AJOL)

    USER

    This is similar to the findings of Akinkugbe and Onilude. (2013) who reported that protease from Lactobacillus acidophilus had maximum activity at 2% casein concentration. Gerze et al. (2005) obtained a slightly lesser value (1.2%) for protease produced by Bacillus subtilis megaterium (BSM) in their study on the effect of.

  4. A cyclic peptidic serine protease inhibitor

    DEFF Research Database (Denmark)

    Zhao, Baoyu; Xu, Peng; Jiang, Longguang

    2014-01-01

    Peptides are attracting increasing interest as protease inhibitors. Here, we demonstrate a new inhibitory mechanism and a new type of exosite interactions for a phage-displayed peptide library-derived competitive inhibitor, mupain-1 (CPAYSRYLDC), of the serine protease murine urokinase...

  5. Optimization of alkaline protease production from Pseudomonas ...

    African Journals Online (AJOL)

    A protease producing bacteria was isolated from meat waste contaminated soil and identified as Pseudomonas fluorescens. Optimization of the fermentation medium for maximum protease production was carried out. The culture conditions like inoculum concentration, incubation time, pH, temperature, carbon sources, ...

  6. Efficacy and safety of direct-acting antiviral regimens in HIV/HCV-co-infected patients - French ANRS CO13 HEPAVIH cohort.

    Science.gov (United States)

    Piroth, Lionel; Wittkop, Linda; Lacombe, Karine; Rosenthal, Eric; Gilbert, Camille; Miailhes, Patrick; Carrieri, Patrizia; Chas, Julie; Poizot-Martin, Isabelle; Gervais, Anne; Dominguez, Stéphanie; Neau, Didier; Zucman, David; Billaud, Eric; Morlat, Philippe; Aumaitre, Hugues; Lascoux-Combe, Caroline; Simon, Anne; Bouchaud, Olivier; Teicher, Elina; Bani-Sadr, Firouzé; Alric, Laurent; Vittecoq, Daniel; Boué, François; Duvivier, Claudine; Valantin, Marc-Antoine; Esterle, Laure; Dabis, François; Sogni, Philippe; Salmon, Dominique

    2017-07-01

    There is little data available on the use of new oral direct-acting antiviral (DAA) regimens to treat human immunodeficiency virus and hepatitis C virus (HIV/HCV) co-infected patients in real-life settings. Here, the efficacy and safety of all-oral DAA-based regimens in HIV/HCV-co-infected patients enrolled in the French nationwide ANRS CO13 HEPAVIH observational cohort are reported. HIV/HCV-co-infected patients enrolled in the ANRS CO13 HEPAVIH observational cohort were included if they began an all-oral DAA-based regimen before 1st May 2015 (12-week regimens) or 1st February 2015 (24-week regimens). Treatment success (SVR12) was defined by undetectable HCV-RNA 12weeks after treatment cessation. Exact logistic regression analysis was used to identify factors associated with SVR12. A total of 323 patients (74% men) with a median age of 53years were included, 99% of whom were on combination antiretroviral therapy (cART). HIV RNA load was <50 copies/ml in 88% of patients; median CD4 cell count was 540/mm(3); 60% of patients were cirrhotic; 68% had previously received unsuccessful anti-HCV treatment. cART was protease inhibitor (PI)-based in 23%, non-nucleoside reverse transcriptase inhibitor (NNRTI)-based in 15%, and integrase inhibitor (II)-based in 38%, while 24% of patients received other regimens. The SVR12 rate was 93.5% overall (95% confidence interval [CI]: 90.2-95.9), 93.3% (88.8-96.4) in patients with cirrhosis and 93.8% (88.1-97.3) in patients without cirrhosis. The SVR12 rates were 93.1% (84.5-97.7), 91.8% (80.4-97.7) and 95.8% (90.5-98.6) respectively, in patients receiving PI-based, NNRTI-based and II-based cART. In adjusted analysis, SVR12 was not associated with HIV RNA load, the cART regimen, cirrhosis, prior anti-HCV treatment, the duration of anti-HCV therapy, or ribavirin use. The most common adverse effects were fatigue and digestive disorders. New all-oral DAA regimens were well-tolerated and yielded high SVR12 rates in HIV/HCV

  7. The Rationale for a Preventative HCV Virus-Like Particle (VLP Vaccine

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    Joseph Torresi

    2017-11-01

    Full Text Available HCV represents a global health problem with ~200 million individuals currently infected, worldwide. With the high cost of antiviral therapies, the global burden of chronic hepatitis C infection (CHCV infection will be substantially reduced by the development of an effective vaccine for HCV. The field of HCV vaccines is generally divided into proponents of strategies to induce neutralizing antibodies (NAb and those who propose to elicit cell mediated immunity (CMI. However, for a hepatitis C virus (HCV vaccine to be effective in preventing infection, it must be capable of generating cross-reactive CD4+, CD8+ T cell, and NAb responses that will cover the major viral genotypes. Simulation models of hepatitis C have predicted that a vaccine of even modest efficacy and coverage will significantly reduce the incidence of hepatitis C. A HCV virus like particle (VLP based vaccine would fulfill the requirement of delivering critical conformational neutralizing epitopes in addition to providing HCV specific CD4+ and CD8+ epitopes. Several approaches have been reported including insect cell-derived genotype 1b HCV VLPs; a human liver-derived quadrivalent genotype 1a, 1b, 2, and 3a vaccine; a genotype 1a HCV E1 and E2 glycoprotein/MLV Gag pseudotype VLP vaccine; and chimeric HBs-HCV VLP vaccines. All to result in the production of cross-NAb and/or T cell responses against HCV. This paper summarizes the evidence supporting the development of a HCV VLP based vaccine.

  8. Proteasome- and Ethanol-Dependent Regulation of HCV-Infection Pathogenesis

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    Natalia A. Osna

    2014-09-01

    Full Text Available This paper reviews the role of the catabolism of HCV and signaling proteins in HCV protection and the involvement of ethanol in HCV-proteasome interactions. HCV specifically infects hepatocytes, and intracellularly expressed HCV proteins generate oxidative stress, which is further exacerbated by heavy drinking. The proteasome is the principal proteolytic system in cells, and its activity is sensitive to the level of cellular oxidative stress. Not only host proteins, but some HCV proteins are degraded by the proteasome, which, in turn, controls HCV propagation and is crucial for the elimination of the virus. Ubiquitylation of HCV proteins usually leads to the prevention of HCV propagation, while accumulation of undegraded viral proteins in the nuclear compartment exacerbates infection pathogenesis. Proteasome activity also regulates both innate and adaptive immunity in HCV-infected cells. In addition, the proteasome/immunoproteasome is activated by interferons, which also induce “early” and “late” interferon-sensitive genes (ISGs with anti-viral properties. Cleaving viral proteins to peptides in professional immune antigen presenting cells and infected (“target” hepatocytes that express the MHC class I-antigenic peptide complex, the proteasome regulates the clearance of infected hepatocytes by the immune system. Alcohol exposure prevents peptide cleavage by generating metabolites that impair proteasome activity, thereby providing escape mechanisms that interfere with efficient viral clearance to promote the persistence of HCV-infection.

  9. Clearance of low levels of HCV viremia in the absence of a strong adaptive immune response

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    Manns Michael P

    2007-06-01

    Full Text Available Abstract Spontaneous clearance of hepatitis C virus (HCV has frequently been associated with the presence of HCV-specific cellular immunity. However, there had been also reports in chimpanzees demonstrating clearance of HCV-viremia in the absence of significant levels of detectable HCV-specific cellular immune responses. We here report seven asymptomatic acute hepatitis C cases with peak HCV-RNA levels between 300 and 100.000 copies/ml who all cleared HCV-RNA spontaneously. Patients were identified by a systematic screening of 1176 consecutive new incoming offenders in a German young offender institution. Four of the seven patients never developed anti-HCV antibodies and had normal ALT levels throughout follow-up. Transient weak HCV-specific CD4+ T cell responses were detectable in five individuals which did not differ in strength and breadth from age- and sex-matched patients with chronic hepatitis C and long-term recovered patients. In contrast, HCV-specific MHC-class-I-tetramer-positive cells were found in 3 of 4 HLA-A2-positive patients. Thus, these cases highlight that clearance of low levels of HCV viremia is possible in the absence of a strong adaptive immune response which might explain the low seroconversion rate after occupational exposure to HCV.

  10. Retention in buprenorphine treatment is associated with improved HCV care outcomes.

    Science.gov (United States)

    Norton, B L; Beitin, A; Glenn, M; DeLuca, J; Litwin, A H; Cunningham, C O

    2017-04-01

    Persons who inject drugs, most of whom are opioid dependent, comprise the majority of the HCV infected in the United States. As the national opioid epidemic unfolds, increasing numbers of people are entering the medical system to access treatment for opioid use disorder, specifically with buprenorphine. Yet little is known about HCV care in patients accessing buprenorphine-based opioid treatment. We sought to determine the HCV prevalence, cascade of care, and the association between patient characteristics and completion of HCV cascade of care milestones for patients initiating buprenorphine treatment. We reviewed electronic health records of all patients who initiated buprenorphine treatment at a primary-care clinic in the Bronx, NY between January 2009 and January 2014. Of the 390 patients who initiated buprenorphine treatment, 123 were confirmed to have chronic HCV infection. The only patient characteristic associated with achieving HCV care milestones was retention in opioid treatment. Patients retained (vs. not retained) in buprenorphine treatment were more likely to be referred for HCV specialty care (63.1% vs. 34.0%, pbuprenorphine treatment, there is an unprecedented opportunity to access and treat persons with HCV, reducing HCV transmission, morbidity and mortality. Retention in opioid treatment may improve linkage and retention in HCV care; innovative models of care that integrate opioid drug treatment with HCV treatment are essential. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Peripheral blood mononuclear cells of HIV- and HCV-antibody-positive individuals contain HCV RNA but No HCV DNA despite evidence for reverse transcription of HIV RNA into DNA

    NARCIS (Netherlands)

    Penning, M.; Beld, M.; Goudsmit, J.

    2000-01-01

    Following reports of the finding of cDNA of RNA viruses in cells containing an endogenous retrovirus-encoded reverse transcriptase, we looked for the presence of hepatitis C virus (HCV) DNA in peripheral blood mononuclear cells (PBMC) of injecting drug users seropositive for both HCV and human

  12. Production of alkaline protease from Cellulosimicrobium cellulans

    Science.gov (United States)

    Ferracini-Santos, Luciana; Sato, Hélia H

    2009-01-01

    Cellulosimicrobium cellulans is one of the microorganisms that produces a wide variety of yeast cell wall-degrading enzymes, β-1,3-glucanase, protease and chitinase. Dried cells of Saccharomyces cerevisiae were used as carbon and nitrogen source for cell growth and protease production. The medium components KH2PO4, KOH and dried yeast cells showed a significant effect (pproduction of protease was 0.2 g/l of MgSO4.7H2O, 2.0 g/l of (NH4)2SO4 and 8% of dried yeast cells in 0.15M phosphate buffer at pH 8.0. The maximum alkaline protease production was 7.0 ± 0.27 U/ml over the center point. Crude protease showed best activity at 50ºC and pH 7.0-8.0, and was stable at 50ºC. PMID:24031317

  13. Protease-degradable electrospun fibrous hydrogels

    Science.gov (United States)

    Wade, Ryan J.; Bassin, Ethan J.; Rodell, Christopher B.; Burdick, Jason A.

    2015-03-01

    Electrospun nanofibres are promising in biomedical applications to replicate features of the natural extracellular matrix (ECM). However, nearly all electrospun scaffolds are either non-degradable or degrade hydrolytically, whereas natural ECM degrades proteolytically, often through matrix metalloproteinases. Here we synthesize reactive macromers that contain protease-cleavable and fluorescent peptides and are able to form both isotropic hydrogels and electrospun fibrous hydrogels through a photoinitiated polymerization. These biomimetic scaffolds are susceptible to protease-mediated cleavage in vitro in a protease dose-dependent manner and in vivo in a subcutaneous mouse model using transdermal fluorescent imaging to monitor degradation. Importantly, materials containing an alternate and non-protease-cleavable peptide sequence are stable in both in vitro and in vivo settings. To illustrate the specificity in degradation, scaffolds with mixed fibre populations support selective fibre degradation based on individual fibre degradability. Overall, this represents a novel biomimetic approach to generate protease-sensitive fibrous scaffolds for biomedical applications.

  14. Post-translational modifications of hepatitis C viral proteins and their biological significance.

    Science.gov (United States)

    Hundt, Jana; Li, Zhubing; Liu, Qiang

    2013-12-21

    Replication of hepatitis C virus (HCV) depends on the interaction of viral proteins with various host cellular proteins and signalling pathways. Similar to cellular proteins, post-translational modifications (PTMs) of HCV proteins are essential for proper protein function and regulation, thus, directly affecting viral life cycle and the generation of infectious virus particles. Cleavage of the HCV polyprotein by cellular and viral proteases into more than 10 proteins represents an early protein modification step after translation of the HCV positive-stranded RNA genome. The key modifications include the regulated intramembranous proteolytic cleavage of core protein, disulfide bond formation of core, glycosylation of HCV envelope proteins E1 and E2, methylation of nonstructural protein 3 (NS3), biotinylation of NS4A, ubiquitination of NS5B and phosphorylation of core and NS5B. Other modifications like ubiquitination of core and palmitoylation of core and NS4B proteins have been reported as well. For some modifications such as phosphorylation of NS3 and NS5A and acetylation of NS3, we have limited understanding of their effects on HCV replication and pathogenesis while the impact of other modifications is far from clear. In this review, we summarize the available information on PTMs of HCV proteins and discuss their relevance to HCV replication and pathogenesis.

  15. Effectiveness of Ritonavir-Boosted Protease Inhibitor Monotherapy in Clinical Practice Even with Previous Virological Failures to Protease Inhibitor-Based Regimens.

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    Luis F López-Cortés

    Full Text Available Significant controversy still exists about ritonavir-boosted protease inhibitor monotherapy (mtPI/rtv as a simplification strategy that is used up to now to treat patients that have not experienced previous virological failure (VF while on protease inhibitor (PI -based regimens. We have evaluated the effectiveness of two mtPI/rtv regimens in an actual clinical practice setting, including patients that had experienced previous VF with PI-based regimens.This retrospective study analyzed 1060 HIV-infected patients with undetectable viremia that were switched to lopinavir/ritonavir or darunavir/ritonavir monotherapy. In cases in which the patient had previously experienced VF while on a PI-based regimen, the lack of major HIV protease resistance mutations to lopinavir or darunavir, respectively, was mandatory. The primary endpoint of this study was the percentage of participants with virological suppression after 96 weeks according to intention-to-treat analysis (non-complete/missing = failure.A total of 1060 patients were analyzed, including 205 with previous VF while on PI-based regimens, 90 of whom were on complex therapies due to extensive resistance. The rates of treatment effectiveness (intention-to-treat analysis and virological efficacy (on-treatment analysis at week 96 were 79.3% (CI95, 76.8-81.8 and 91.5% (CI95, 89.6-93.4, respectively. No relationships were found between VF and earlier VF while on PI-based regimens, the presence of major or minor protease resistance mutations, the previous time on viral suppression, CD4+ T-cell nadir, and HCV-coinfection. Genotypic resistance tests were available in 49 out of the 74 patients with VFs and only four patients presented new major protease resistance mutations.Switching to mtPI/rtv achieves sustained virological control in most patients, even in those with previous VF on PI-based regimens as long as no major resistance mutations are present for the administered drug.

  16. Discovery of an irreversible HCV NS5B polymerase inhibitor.

    Science.gov (United States)

    Zeng, Qingbei; Nair, Anilkumar G; Rosenblum, Stuart B; Huang, Hsueh-Cheng; Lesburg, Charles A; Jiang, Yueheng; Selyutin, Oleg; Chan, Tin-Yau; Bennett, Frank; Chen, Kevin X; Venkatraman, Srikanth; Sannigrahi, Mousumi; Velazquez, Francisco; Duca, Jose S; Gavalas, Stephen; Huang, Yuhua; Pu, Haiyan; Wang, Li; Pinto, Patrick; Vibulbhan, Bancha; Agrawal, Sony; Ferrari, Eric; Jiang, Chuan-kui; Li, Cheng; Hesk, David; Gesell, Jennifer; Sorota, Steve; Shih, Neng-Yang; Njoroge, F George; Kozlowski, Joseph A

    2013-12-15

    The discovery of lead compound 2e was described. Its covalent binding to HCV NS5B polymerase enzyme was investigated by X-ray analysis. The results of distribution, metabolism and pharmacokinetics were reported. Compound 2e was demonstrated to be potent (replicon GT-1b EC50 = 0.003 μM), highly selective, and safe in in vitro and in vivo assays. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Drug Abuse, HIV, and HCV in Asian Countries.

    Science.gov (United States)

    Hser, Yih-Ing; Liang, Di; Lan, Yu-Ching; Vicknasingam, Balasingam Kasinather; Chakrabarti, Amit

    2016-09-01

    Drug abuse and co-occurring infections are associated with significant morbidity and mortality. Asian countries are particularly vulnerable to the deleterious consequences of these risks/problems, as they have some of the highest rates of these diseases. This review describes drug abuse, HIV, and hepatitis C (HCV) in Asian countries. The most commonly used illicit drugs include opioids, amphetamine-type stimulants (ATS), cannabis, and ketamine. Among people who inject drugs, HIV rates range from 6.3 % in China to 19 % in Malaysia, and HCV ranges from 41 % in India and Taiwan to 74 % in Vietnam. In the face of the HIV epidemics, drug policies in these countries are slowly changing from the traditional punitive approach (e.g., incarcerating drug users or requiring registration as a drug user) to embrace public health approaches, including, for example, community-based treatment options as well as harm reduction approaches to reduce needle sharing and thus HIV transmission. HIV and HCV molecular epidemiology indicates limited geographic diffusion. While the HIV prevalence is declining in all five countries, use of new drugs (e.g., ATS, ketamine) continues to increase, as well as high-risk sexual behaviors associated with drug use-increasing the risk of sexual transmission of HIV, particularly among men who have sex with men. Screening, early intervention, and continued scaling up of therapeutic options (drug treatment and recovery support, ART, long-term HIV and HCV care for drug users) are critical for effective control or continued reduction of drug abuse and co-infections.

  18. Ledipasvir and sofosbuvir for untreated HCV genotype 1 infection.

    Science.gov (United States)

    Afdhal, Nezam; Zeuzem, Stefan; Kwo, Paul; Chojkier, Mario; Gitlin, Norman; Puoti, Massimo; Romero-Gomez, Manuel; Zarski, Jean-Pierre; Agarwal, Kosh; Buggisch, Peter; Foster, Graham R; Bräu, Norbert; Buti, Maria; Jacobson, Ira M; Subramanian, G Mani; Ding, Xiao; Mo, Hongmei; Yang, Jenny C; Pang, Phillip S; Symonds, William T; McHutchison, John G; Muir, Andrew J; Mangia, Alessandra; Marcellin, Patrick

    2014-05-15

    In phase 2 studies, treatment with the all-oral combination of the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor ledipasvir resulted in high rates of sustained virologic response among previously untreated patients with hepatitis C virus (HCV) genotype 1 infection. We conducted a phase 3, open-label study involving previously untreated patients with chronic HCV genotype 1 infection. Patients were randomly assigned in a 1:1:1:1 ratio to receive ledipasvir and sofosbuvir in a fixed-dose combination tablet once daily for 12 weeks, ledipasvir-sofosbuvir plus ribavirin for 12 weeks, ledipasvir-sofosbuvir for 24 weeks, or ledipasvir-sofosbuvir plus ribavirin for 24 weeks. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. Of the 865 patients who underwent randomization and were treated, 16% had cirrhosis, 12% were black, and 67% had HCV genotype 1a infection. The rates of sustained virologic response were 99% (95% confidence interval [CI], 96 to 100) in the group that received 12 weeks of ledipasvir-sofosbuvir; 97% (95% CI, 94 to 99) in the group that received 12 weeks of ledipasvir-sofosbuvir plus ribavirin; 98% (95% CI, 95 to 99) in the group that received 24 weeks of ledipasvir-sofosbuvir; and 99% (95% CI, 97 to 100) in the group that received 24 weeks of ledipasvir-sofosbuvir plus ribavirin. No patient in either 12-week group discontinued ledipasvir-sofosbuvir owing to an adverse event. The most common adverse events were fatigue, headache, insomnia, and nausea. Once-daily ledipasvir-sofosbuvir with or without ribavirin for 12 or 24 weeks was highly effective in previously untreated patients with HCV genotype 1 infection. (Funded by Gilead Sciences; ION-1 ClinicalTrials.gov number NCT01701401.).

  19. Host genetics predict clinical deterioration in HCV-related cirrhosis.

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    Lindsay Y King

    Full Text Available Single nucleotide polymorphisms (SNPs in the epidermal growth factor (EGF, rs4444903, patatin-like phospholipase domain-containing protein 3 (PNPLA3, rs738409 genes, and near the interleukin-28B (IL28B, rs12979860 gene are linked to treatment response, fibrosis, and hepatocellular carcinoma (HCC in chronic hepatitis C. Whether these SNPs independently or in combination predict clinical deterioration in hepatitis C virus (HCV-related cirrhosis is unknown. We genotyped SNPs in EGF, PNPLA3, and IL28B from liver tissue from 169 patients with biopsy-proven HCV cirrhosis. We estimated risk of clinical deterioration, defined as development of ascites, encephalopathy, variceal hemorrhage, HCC, or liver-related death using Cox proportional hazards modeling. During a median follow-up of 6.6 years, 66 of 169 patients experienced clinical deterioration. EGF non-AA, PNPLA3 non-CC, and IL28B non-CC genotypes were each associated with increased risk of clinical deterioration in age, sex, and race-adjusted analysis. Only EGF non-AA genotype was independently associated with increased risk of clinical deterioration (hazard ratio [HR] 2.87; 95% confidence interval [CI] 1.31-6.25 after additionally adjusting for bilirubin, albumin, and platelets. Compared to subjects who had 0-1 unfavorable genotypes, the HR for clinical deterioration was 1.79 (95%CI 0.96-3.35 for 2 unfavorable genotypes and 4.03 (95%CI 2.13-7.62 for unfavorable genotypes for all three loci (Ptrend<0.0001. In conclusion, among HCV cirrhotics, EGF non-AA genotype is independently associated with increased risk for clinical deterioration. Specific PNPLA3 and IL28B genotypes also appear to be associated with clinical deterioration. These SNPs have potential to identify patients with HCV-related cirrhosis who require more intensive monitoring for decompensation or future therapies preventing disease progression.

  20. Review article: HCV – STAT-C era of therapy

    OpenAIRE

    Lange, Christian Markus; Sarrazin, Christoph; Zeuzem, Stefan

    2010-01-01

    Abstract Background: Numerous ?specifically targeted antiviral therapy for hepatitis C? (STAT-C) compounds are currently under development to improve treatment opportunities of chronic hepatitis C virus-(HCV)-infection. Aim: To review the potential of STAT-C agents which are currently under clinical development. Methods: Studies evaluating STAT-C compounds were identified by systematic literature search using PubMed and databases of abstracts presented in English at recent l...

  1. Modulations of cell cycle checkpoints during HCV associated disease

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    Jafri Wasim

    2009-08-01

    Full Text Available Abstract Background Impaired proliferation of hepatocytes has been reported in chronic Hepatitis C virus infection. Considering the fundamental role played by cell cycle proteins in controlling cell proliferation, altered regulation of these proteins could significantly contribute to HCV disease progression and subsequent hepatocellular carcinoma (HCC. This study aimed to identify the alterations in cell cycle genes expression with respect to early and advanced disease of chronic HCV infection. Methods Using freshly frozen liver biopsies, mRNA levels of 84 cell cycle genes in pooled RNA samples from patients with early or advanced fibrosis of chronic HCV infection were studied. To associate mRNA levels with respective protein levels, four genes (p27, p15, KNTC1 and MAD2L1 with significant changes in mRNA levels (> 2-fold, p-value Results In the early fibrosis group, increased mRNA levels of cell proliferation genes as well as cell cycle inhibitor genes were observed. In the advanced fibrosis group, DNA damage response genes were up-regulated while those associated with chromosomal stability were down-regulated. Increased expression of CDK inhibitor protein p27 was consistent with its mRNA level detected in early group while the same was found to be negatively associated with liver fibrosis. CDK inhibitor protein p15 was highly expressed in both early and advanced group, but showed no correlation with fibrosis. Among the mitotic checkpoint regulators, expression of KNTC1 was significantly reduced in advanced group while MAD2L1 showed a non-significant decrease. Conclusion Collectively these results are suggestive of a disrupted cell cycle regulation in HCV-infected liver. The information presented here highlights the potential of identified proteins as predictive factors to identify patients with high risk of cell transformation and HCC development.

  2. Peripheral nervous system involvement in HCV-related mixed cryoglobulinemia

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    F. Bravaccio

    2011-09-01

    Full Text Available In HCV-related mixed cryoglobulinemia (MC a peripheral neuropathy (PN may occur. To evaluate the prevalence and the characteristics of PN, 133 consecutive patients with HCV-MC (117 type II, 16 type III were studied. Neurologic evaluation was performed according to the guidelines of Italian Group for the Study of Cryoglobulinemias, using a neurological disability score and a neurological symptom score. In 52/133 patients an electrophysiologic study (ENG of ulnar, peroneal and sural nerves was performed. For 27/52 patients ENG data registered at different times (interval 12-96 months were available. In 11 patients a sural nerve biopsy was obtained. An overt PN, mostly as sensory asymmetrical or symmetrical nerve impairement, was found in 107/133 patients (80.4%. ENG abnormalities-reduction or absence of sensory and sometimes of motor action potential, normal or slightly impaired nerve conduction velocity, consistent with axonal damage- were detected in 48/52 patients (92.3%. In 26 out of the 27 patients observed at different times an evolution of PN was found. Nerve biopsies showed a prevalent axonal damage, swollen endotelial cells in epi- and perineurial vessels and scarce mononuclear perivascular infiltrates. No leukocytoclastic vasculitis was observed. Immunoglobulins and complement in sub-perineurial vessel wall were detected. Conclusions. In HCV-MC a PN is frequent. It is mostly a sensory and progressively worsenig axonopathy. Different mechanisms may be involved in the pathogenesis of this disorder and a direct role of HCV cannot be excluded.

  3. A biotechnology perspective of fungal proteases

    Science.gov (United States)

    de Souza, Paula Monteiro; Bittencourt, Mona Lisa de Assis; Caprara, Carolina Canielles; de Freitas, Marcela; de Almeida, Renata Paula Coppini; Silveira, Dâmaris; Fonseca, Yris Maria; Ferreira, Edivaldo Ximenes; Pessoa, Adalberto; Magalhães, Pérola Oliveira

    2015-01-01

    Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications. PMID:26273247

  4. A biotechnology perspective of fungal proteases

    Directory of Open Access Journals (Sweden)

    Paula Monteiro de Souza

    2015-06-01

    Full Text Available Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications.

  5. Gut proteases target Yersinia invasin in vivo

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    Freund Sandra

    2011-04-01

    Full Text Available Abstract Background Yersinia enterocolitica is a common cause of food borne gastrointestinal disease. After oral uptake, yersiniae invade Peyer's patches of the distal ileum. This is accomplished by the binding of the Yersinia invasin to β1 integrins on the apical surface of M cells which overlie follicle associated lymphoid tissue. The gut represents a barrier that severely limits yersiniae from reaching deeper tissues such as Peyer's patches. We wondered if gut protease attack on invasion factors could contribute to the low number of yersiniae invading Peyer's patches. Findings Here we show that invasin is rapidly degraded in vivo by gut proteases in the mouse infection model. In vivo proteolytic degradation is due to proteolysis by several gut proteases such as trypsin, α-chymotrypsin, pancreatic elastase, and pepsin. Protease treated yersiniae are shown to be less invasive in a cell culture model. YadA, another surface adhesin is cleaved by similar concentrations of gut proteases but Myf was not cleaved, showing that not all surface proteins are equally susceptible to degradation by gut proteases. Conclusions We demonstrate that gut proteases target important Yersinia virulence factors such as invasin and YadA in vivo. Since invasin is completely degraded within 2-3 h after reaching the small intestine of mice, it is no longer available to mediate invasion of Peyer's patches.

  6. Engaging HIV-HCV co-infected patients in HCV treatment: the roles played by the prescribing physician and patients' beliefs (ANRS CO13 HEPAVIH cohort, France

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    Salmon-Ceron Dominique

    2012-03-01

    Full Text Available Abstract Background Treatment for the hepatitis C virus (HCV may be delayed significantly in HIV/HCV co-infected patients. Our study aims at identifying the correlates of access to HCV treatment in this population. Methods We used 3-year follow-up data from the HEPAVIH ANRS-CO13 nationwide French cohort which enrolled patients living with HIV and HCV. We included pegylated interferon and ribavirin-naive patients (N = 600 at enrolment. Clinical/biological data were retrieved from medical records. Self-administered questionnaires were used for both physicians and their patients to collect data about experience and behaviors, respectively. Results Median [IQR] follow-up was 12[12-24] months and 124 patients (20.7% had started HCV treatment. After multiple adjustment including patients' negative beliefs about HCV treatment, those followed up by a general practitioner working in a hospital setting were more likely to receive HCV treatment (OR[95%CI]: 1.71 [1.06-2.75]. Patients followed by general practitioners also reported significantly higher levels of alcohol use, severe depressive symptoms and poor social conditions than those followed up by other physicians. Conclusions Hospital-general practitioner networks can play a crucial role in engaging patients who are the most vulnerable and in reducing existing inequities in access to HCV care. Further operational research is needed to assess to what extent these models can be implemented in other settings and for patients who bear the burden of multiple co-morbidities.

  7. Look-back of anti-HCV ELISA-positive, HCV-RNA PCR-negative donors and recipients of their blood products

    NARCIS (Netherlands)

    Vrielink, H.; Reésink, H. W.; Zaaijer, H. L.; Scholten, E.; Kremer, L. C.; Cuypers, H. T.; Lelie, P. N.; van Oers, M. H.; van der Poel, C. L.

    1997-01-01

    BACKGROUND AND OBJECTIVES: To establish the infectivity of anti-HCV ELISA-positive, but cDNA-PCR-negative blood components transfused before the introduction of routine anti-HCV blood donor screening, we enrolled recipients of such blood products in a look-back programme. MATERIALS AND METHODS: The

  8. Are RA patients from a non-endemic HCV population screened for HCV? A cross-sectional analysis of three different settings.

    Science.gov (United States)

    Skinner-Taylor, Cassandra Michelle; Erhard-Ramírez, Alejandro; Garza-Elizondo, Mario Alberto; Esquivel-Valerio, Jorge Antonio; Abud-Mendoza, Carlos; Martínez-Martínez, Marco Ulises; Vega-Morales, David; Arana-Guajardo, Ana

    In Mexico, other risk factors are associated with hepatitis C virus (HCV): prior heroin users, living alone, widower, and northern region residence. Rheumatoid arthritis (RA) patients are considered immunosuppressed and HCV testing is recommended before treatment. The aim of the study was to describe the characteristics of HCV testing in RA patients in three different medical care settings in a non-endemic area. A retrospective observational study was performed using medical records from 960 RA patients describing the indications for HCV testing. The test was performed in 28.6% and the HCV overall frequency was 0.36%. Population characteristics were not associated with an increased risk of HCV infection; therefore, anti-HCV positivity was low. The main reason for testing was before starting biological agents. Due to the low pre-test probability, testing for HCV infection should be personalized; i.e., according to disease prevalence in a particular geographical location and the individual risk factors. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  9. HEPATITIS C VIRUS (HCV) SEROPREVALENCE, ANTIGENAEMIA AND ASSOCIATED RISK FACTORS AMONG PREGNANT WOMEN IN NIGERIA.

    Science.gov (United States)

    Owolabi, Omolola Beatrice; Adesina, Kikelomo Temilola; Fadeyi, Abayomi; Popoola, Gbenga

    2015-10-01

    Hepatitis C viral infection is a significant public health challenge with potential risk of progressing to liver cirrhosis and hepatocellular carcinoma (HCC). Actively infected mothers can transmit the virus to their babies who may develop liver cirrhosis and HCC as young adults. We determined the seroprevalence of HCV, its antigenaemia and associated risk factors among pregnant women. We recruited 400 pregnant women and tested their serum for HCV antibodies using immune-chromatographic test and determined the HCV core antigenaemia among HCV sero-positives by enzyme-immunoassay (EIA). The bio-socio-demographic variables of the participants were statistically correlated to the test results. Seroprevalence of HCV was 5.8% (23/400) and the prevalence of HCV core antigenaemia was 73.9% (17/23). None of the bio-socio-demographic variables of the participants and other known risk factors evaluated had. significant influence on either seroprevalence of HCV or its antigenaemia. Only the employment status of the participants' husbands (p = 0.01) significantly affected seropositivity of HCV. HCV core antigenaemia is high among pregnant women who have antibodies to HCV in our environment and this signifies an active hepatitis C virus infection.

  10. Contemporary protease inhibitors and cardiovascular risk

    DEFF Research Database (Denmark)

    Lundgren, Jens; Mocroft, Amanda; Ryom, Lene

    2018-01-01

    PURPOSE OF REVIEW: To review the evidence linking use of HIV protease inhibitors with excess risk of cardiovascular disease (CVD) in HIV+ populations. RECENT FINDINGS: For the two contemporary most frequently used protease inhibitors, darunavir and atazanavir [both pharmacologically boosted...... with ritonavir (/r)], darunavir/r has been shown to be associated with increased CVD risk. The effect is cumulative with longer exposure increasing risk and an effect size comparable to what has been observed for previously developed protease inhibitors. Biological mechanisms may be overlapping and include...... on individualization of care based on underlying risk of CVD....

  11. Mass spectrometry-assisted protease substrate screening

    DEFF Research Database (Denmark)

    Schlüter, Hartmut; Rykl, Jana; Thiemann, Joachim

    2007-01-01

    Since sequencing of the human genome was completed, more than 500 genes have been annotated as proteases. Exploring the physiological role of each protease requires the identification of their natural substrates. However, the endogenous substrates of many of the human proteases are as yet unknown......-phase chromatography they are analyzed by tandem mass spectrometry and the substrates identified by database searching. The proof of principle in this study is demonstrated by incubating immobilized human plasma proteins with thrombin and by identifying by tandem mass spectrometry the fibrinopeptides, released...

  12. Analysis of hepatitis non-treatment causes in a cohort of HCV and HCV/HIV infected patients

    Directory of Open Access Journals (Sweden)

    Karen Pereira

    2014-11-01

    Full Text Available Introduction: The decision to start hepatitis C virus (HCV treatment and its timing remains controversial. As new treatment regimens are approved, it is essential to identify patients eligible for each regimen in a timed and tailored approach. This study aims to identify the reasons to defer treatment of chronic hepatitis C infection in both HCV and HCV/HIV infected patients. Materials and Methods: Retrospective observational study of a cohort of HCV chronically infected patients with or without HIV infection, followed in an infectious disease clinic in Lisbon. Demographic, epidemiological, clinical, immunologic and virologic data were collected. Statistical analysis was performed with Microsoft Office®- Excel 2012. Kolmogorov-Smirnov, t-test, Chi-square and correlation analysis were performed for a significant p value<0.05. Results: The study included 669 patients, 225 patients infected with HCV (group A and 444 patients co-infected with HCV/HIV (group B. The comparative analysis of those groups (A vs. B showed: mean age was 49.4 years versus 46.9 (p<0.01, mean time since HCV diagnosis was 9.5 versus 14.6 years (p=0.558 both groups shared a male predominance and HCV acquisition due to intravenous drug use. Regarding genotype characterization, the predominant was 1a in both groups (p<0.01. Evaluation of IL28B polymorphism revealed CC 15.5% (A versus 9.45% (B (p<0.01. Group B mean TCD4 count was 585 cells/µL (mean percentage 27.1%. There was spontaneous viral clearance in 10.7% (A versus 4.1% (B (p<0.01. There were treated 52.0% (A versus 32.2% (B patients (p<0.01. For the untreated ones (107 – group A vs 270 – group B, no reason was identified for treatment deferral in 32.5% (A versus 48.0% (B patients. The most frequent reasons for deferring treatment were: withdrawal to follow-up (33.7%, active staging of disease (7.2%, alcohol abuse (6.0% and advanced age (6.0% in group A versus low TCD4 cell count (17.1%, loss to follow-up (7.5%, poor

  13. Intrahepatic Vγ9Vδ2 T-cells from HCV-infected patients show an exhausted phenotype but can inhibit HCV replication.

    Science.gov (United States)

    Cimini, E; Bordoni, V; Sacchi, A; Visco-Comandini, U; Montalbano, M; Taibi, C; Casetti, R; Lalle, E; D'Offizi, G; Capobianchi, M R; Agrati, C

    2018-01-02

    Hepatitis C virus (HCV) persistence results from inefficiencies of both innate and adaptive immune responses to eradicate the infection. A functional impairment of circulating Vγ9Vδ2 T-cells was described but few data are available on Vγ9Vδ2 T-cells in the liver that, however, represents the battlefield in the HCV/host interaction. Aim of this work was to compare circulating and intrahepatic Vγ9Vδ2 T-cells in chronic HCV-infected patients (HCVpos) and in HCV-negative (HCVneg) subjects. Phenotypic and functional analysis was performed by flow cytometry. Anti-HCV activity was analyzed by using an in vitro autologous liver culture system. Independently from HCV infection, the liver was enriched of Vγ9Vδ2 T-cells expressing an effector/activated phenotype. In contrast, an enrichment of PD-1 expressing Vγ9Vδ2 T-cells was observed both in the peripheral blood and in the liver of HCVpos patients, probably due to a persistent antigenic stimulation. Moreover, a lower frequency of IFN-γ producing Vγ9Vδ2 T-cells was observed in the liver of HCVpos patients, suggesting a functional impairment in the cytokine production in HCVpos liver. Despite this hypo-responsiveness, intrahepatic Vγ9Vδ2 T-cells are able to exert an anti-HCV activity after specific stimulation. Altogether, our data show that HCV infection induced a dysregulation of intrahepatic Vγ9Vδ2 T cells that maintain their anti-HCV activity after specific stimulation. A study aimed to evaluate the mechanisms of the antiviral activity may be useful to identify new pathways able to improve Vγ9Vδ2 T-cells intrahepatic function during HCV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Transcriptomic assay of CD8+ T cells in treatment-naïve HIV, HCV-mono-infected and HIV/HCV-co-infected Chinese.

    Directory of Open Access Journals (Sweden)

    Jin Zhao

    Full Text Available BACKGROUND: Co-infection with HIV and HCV is very common. It is estimated that over 5 million people are co-infected with HIV and HCV worldwide. Accumulated evidence shows that each virus alters the course of infection of the other one. CD8+ T cells play a crucial role in the eradication of viruses and infected target cells. To the best of our knowledge, no one has investigated the gene expression profiles in HIV/HCV-co-infected individuals. METHODOLOGY: Genome-wide transcriptomes of CD8+ T cells from HIV/HCV-co-infected or mono-infected treatment-naïve individuals were analyzed by microarray assays. Pairwise comparisons were performed and differentially expressed genes were identified followed by quantitative real-time PCR (qRT-PCR validation. Directed Acyclic Graphs (DAG from Web-based Gene SeT AnaLysis Toolkit (WebGestalt and DAVID bioinformatics resources 6.7 (the Database for Annotation, Visualization, and Integrated Discovery were used to discover the Gene Ontology (GO categories with significantly enriched gene numbers. The enriched Kyoto Encyclopedia of Genes and Genomes (KEGG pathways were also obtained by using WebGestalt software. RESULTS AND CONCLUSIONS: A total of 110, 24 and 72 transcript IDs were shown to be differentially expressed (> 2-fold and p<0.05 in comparisons between HCV- and HIV-mono-infected groups, HIV/HCV-co-infected and HIV-mono-infected groups, and HIV/HCV-co-infected and HCV-mono-infected groups, respectively. In qRT-PCR assay, most of the genes showed similar expressing profiles with the observation in microarray assays. Further analysis revealed that genes involved in cell proliferation, differentiation, transcriptional regulation and cytokine responses were significantly altered. These data offer new insights into HIV/HCV co-infections, and may help to identify new markers for the management and treatment of HIV/HCV co-infections.

  15. Detection of hepatitis C virus RNA in saliva samples from patients with seric anti-HCV antibodies

    Directory of Open Access Journals (Sweden)

    Patrícia L. Gonçalves

    Full Text Available We examined the frequency of HCV-RNA in saliva samples from anti-HCV positive patients. Both plasma and saliva samples from 39 HCV patients (13 with normal liver enzymes, 19 with abnormal liver enzymes and 13 with cirrhosis were investigated. Stimulated saliva and fresh plasma were centrifuged (900 x g,10 min and stored at -70ºC, after the addition of guanidine isothiocyanate RNA extraction buffer. HCV-RNA was detected by RT- nested-PCR (amplification of HCV-cDNA for two rounds, using HCV primers 939/209 and 940/211. HCV genotyping was carried out by RFLP (using Mva I and Hinf 1 or Hae III and Rsa I restriction enzymes. Thirty-two out of 39 (82%; 95% CI=70-94% anti-HCV-positive patients had HCV-RNA in plasma samples. Eight out of 39 (20.5%; 95% CI=6.6-34.4% had HCV-RNA in the saliva. The HCV genotype in saliva samples from these patients matched the genotype found for plasma HCV-RNA. No significant correlation between the presence of HCV and either age, gender, HCV genotype or any risk factor for HCV infection was found. The observed prevalence (20.5% of anti HCV positive patients or 25% of the patients with HCV-RNA in plasma was lower than that previously reported from other countries. The low frequency of HCV-RNA in saliva samples observed in our study may be due to the use of cell-free saliva. Other authors reporting higher frequencies of HCV-RNA in saliva used whole saliva, without centrifugation.

  16. Sofosbuvir and Ledipasvir for 8 Weeks for the Treatment of Chronic Hepatitis C Virus (HCV) Infection in HCV-Monoinfected and HIV-HCV-Coinfected Individuals: Results From the German Hepatitis C Cohort (GECCO-01).

    Science.gov (United States)

    Ingiliz, Patrick; Christensen, Stefan; Kimhofer, Torben; Hueppe, Dietrich; Lutz, Thomas; Schewe, Knud; Busch, Heiner; Schmutz, Günther; Wehmeyer, Malte H; Boesecke, Christoph; Simon, Karl-Georg; Berger, Florian; Rockstroh, Jürgen K; Schulze zur Wiesch, Julian; Baumgarten, Axel; Mauss, Stefan

    2016-11-15

    Shortening the duration of treatment with HCV direct-acting antivirals (DAAs) leads to substantial cost reductions. According to the label, sofosbuvir and ledipasvir can be prescribed for 8 weeks (SL8) in noncirrhotic women or men with HCV genotype 1 and low viral loads. However, real-world data about the efficacy and safety of SL8 are largely missing. Interim results from an ongoing prospective, multicenter cohort of 9 treatment centers in Germany (GECCO). All patients started on treatment with HCV DAAs since January 2014 were included. This report describes safety and efficacy outcomes in 210 patients with HCV monoinfection and 35 with human immunodeficiency virus (HIV)-HCV coinfection given SL8 in a real-world setting. Of 1353 patients included into the GECCO cohort until December 2015, a total of 1287 had complete data sets for this analysis; 337 (26.2%) fulfilled the criteria for SL8 according to the package insert, but only 193 (57.2%) were eventually treated for 8 weeks. Another 52 patients did not fulfill the criteria but were treated for 8 weeks. SL8 was generally well tolerated. The overall sustained virologic response rate 12 weeks after the end of treatment was 93.5% (186 of 199). The on-treatment response rate was 99.4% (159 of 160) in HCV-monoinfected and 96.4% (27 of 28) in HIV-HCV-coinfected patients. Ten patients were lost to follow-up. SL8 seems highly effective and safe in well-selected HCV-monoinfected and HIV-HCV-coinfected patients in a real-world setting. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  17. Activation of ADAM 12 protease by copper

    DEFF Research Database (Denmark)

    Loechel, F; Wewer, Ulla M.

    2001-01-01

    Conversion of latent proteases to the active form occurs by various mechanisms characteristic for different protease families. Here we report that the disintegrin metalloprotease ADAM 12-S is activated by Cu(II). Copper activation is distinct from the cysteine switch component of latency: elimina......Conversion of latent proteases to the active form occurs by various mechanisms characteristic for different protease families. Here we report that the disintegrin metalloprotease ADAM 12-S is activated by Cu(II). Copper activation is distinct from the cysteine switch component of latency......: elimination of the ADAM 12 cysteine switch by a point mutation in the propeptide had no effect on copper activation, whereas mutation of an unpaired cysteine residue in the catalytic domain resulted in a mutant form of ADAM 12-S that was insensitive to copper. This suggests a multi-step activation mechanism...... for ADAM 12 involving both furin cleavage and copper binding....

  18. Secreted fungal aspartic proteases: A review.

    Science.gov (United States)

    Mandujano-González, Virginia; Villa-Tanaca, Lourdes; Anducho-Reyes, Miguel Angel; Mercado-Flores, Yuridia

    2016-01-01

    The aspartic proteases, also called aspartyl and aspartate proteases or acid proteases (E.C.3.4.23), belong to the endopeptidase family and are characterized by the conserved sequence Asp-Gly-Thr at the active site. These enzymes are found in a wide variety of microorganisms in which they perform important functions related to nutrition and pathogenesis. In addition, their high activity and stability at acid pH make them attractive for industrial application in the food industry; specifically, they are used as milk-coagulating agents in cheese production or serve to improve the taste of some foods. This review presents an analysis of the characteristics and properties of secreted microbial aspartic proteases and their potential for commercial application. Copyright © 2016 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

  19. Sofosbuvir and ledipasvir for HIV/HCV co-infected patients.

    Science.gov (United States)

    Rosenthal, Elana S; Kottilil, Shyam; Polis, Michael A

    2016-01-01

    Hepatitis C virus (HCV) is a chronic infection that disproportionately impacts people living with HIV. In the past, HCV therapy was less effective in individuals with HIV co-infection. However, the advent of direct-acting antivirals has revolutionized HCV treatment with high rates of success in patients both with and without HIV. In this paper, we review the evidence supporting the use of ledipasvir and sofosbuvir (LDV/SOF) for the treatment of HCV in patients with HIV co-infection. Articles searchable on MEDLINE/PubMed were reviewed to provide context for use of LDV/SOF in individuals with HCV and HIV co-infection. This treatment is highly effective in achieving HCV cure or sustained virologic response, however further studies need to done to address efficacy of treatment in people with uncontrolled HIV, concerns regarding drug-interactions with antiretroviral therapy, and potential for shorter duration treatment.

  20. Undetectable hepatitis C virus RNA during syphilis infection in two HIV/HCV-co-infected patients

    DEFF Research Database (Denmark)

    Salado-Rasmussen, Kirsten; Knudsen, Andreas; Krarup, Henrik Bygum

    2014-01-01

    BACKGROUND: Treponema pallidum, the causative agent of syphilis, elicits a vigorous immune response in the infected host. This study sought to describe the impact of syphilis infection on hepatitis C virus (HCV) RNA levels in patients with HIV and chronic HCV infection. METHODS: Patients...... with chronic HIV/HCV and syphilis co-infection were identified by their treating physicians from 1 October 2010 to 31 December 2013. Stored plasma samples obtained before, during, and after syphilis infection were analysed for interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, tumour necrosis factor alpha (TNF......-α), interferon gamma (IFN-γ), and IFN-γ-inducible protein 10 kDa (IP-10). RESULTS: Undetectable HCV RNA at the time of early latent syphilis infection was observed in 2 patients with HIV and chronic HCV infection. After treatment of the syphilis infection, HCV RNA levels increased again in patient 1, whereas...

  1. Pegylated interferon-alfa plus ribavirin therapies for chronic hepatitis C

    Directory of Open Access Journals (Sweden)

    T Kanda

    2011-03-01

    Full Text Available Until HCV NS3/4A protease inhibitors become available at the end of 2011, the combination pegylated-interferon (PEG-IFN-alfa and ribavirin (RBV will remain the standard treatment for chronic hepatitis C patients. In some hepatitis C virus-infected patients, PEG-IFN plus RBV treatment against HCV should continue to be used because of side effects of new drugs such as anemia. Our Japanese experiences should provide new information for the treatment of chronic hepatitis C. Keywords: Direct-acting antiviral agents (DAA, HCV, pegylated interferon, ribavirin, standard of care (SOC .

  2. Purification and characterization of protease enzyme from ...

    African Journals Online (AJOL)

    Optimum protease activity of 116.4 U/ml was observed in the growth medium containing 0.7% KH2PO4, 0.2% K2HPO4, 0.01% MgSO4.7H2O, 0.05% citric acid dehydrate, 0.1% yeast extract and 0.2% casein. The protease production was found to be optimized in 1: 5 cultivation volume with 1% inoculum, shaken at 150 rpm.

  3. Tooth Development and Funcional Aspects of Proteases

    OpenAIRE

    原田, 実

    1994-01-01

    During tooth development in tooth germs, a chain of reciprocal interactions between the epithelial and mesenchymal tissue regulates both morphogenesis and cell differentiation. Several extracellular matrix proteins such as fibronectin, tenascin, syndecan, collagens, and enamel proteins are thought to be involved in the tooth developing process on a timed schedule. The turnover of these proteins can be broken down with proteases in the tooth germs. In this review article, proteases related to ...

  4. Should HCV discordant couples with a seropositive male partner be treated with assisted reproduction techniques (ART)?

    Science.gov (United States)

    Savasi, Valeria; Oneta, Monica; Parrilla, Bina; Cetin, Irene

    2013-04-01

    The debate on HCV discordant couples requiring assisted reproduction is still open today, and specific guidelines have not yet been established on whether or not physicians should treat HCV discordant couples who require ART. We studied the results of our reproductive assistance with sperm washing in HCV discordant couples, all treated in a single center, including the serological status of mothers and babies, and the outcome of the pregnancies. Prospective study conducted between January 2008 and December 2010 in our Reproductive Center in Sacco Hospital, University of Milan. Thirty-five HCV serodiscordant infertile couples with an HCV viremic positive male partner were enrolled. All of them completed the immuno-virological and fertility triage, and were treated according to our clinical protocols. Forty-seven superovulation and IUI and 38 second-level ART procedures are reported. The pregnancy rates for IUI and ICSI are similar to those reported by the Italian ART register. All the 85 sperm samples were treated with sperm washing technique to reduce HCV in semen and the possible risk of transmission. We did not observe any preterm delivery or negative perinatal outcome. No mothers or babies are infected by HCV. This is the biggest prospective study conducted in a single center involving HCV discordant infertile couples in an ART program. Although sexual transmission of HCV is very low, in subfertile or infertile couples sperm washing should be used to treat HCV positive semen before ART. We suggest that it is not necessary to perform nested PCR to detect HCV RNA in the final swim-up. Since the presence of HCV in semen implies a possible risk of nosocomial contamination, safety regulations must be strictly applied in assisted reproduction laboratories. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. The antiviral protein viperin inhibits HCV replication via interaction with NS5A

    OpenAIRE

    Helbig, Karla J.; Nicholas S Eyre; Yip, Evelyn; Narayana, Sumudu; Li, Kui; Fiches, Guillaume; McCartney, Erin M; Jangra, Rohit K.; Lemon, Stanley M.; Beard, Michael R.

    2011-01-01

    The interferon-stimulated gene viperin has been shown to have antiviral activity against hepatitis C virus (HCV) in the context of the HCV replicon, although the molecular mechanisms responsible are not well understood. Here we demonstrate that viperin plays an integral part in the ability of interferon to limit replication of cell culture derived HCV (JFH-1) that accurately reflects the complete viral life cycle. Using confocal microscopy and Fluorescence Resonance Energy Transfer (FRET) ana...

  6. Prevalence of HBV and HCV Infections and Associated Risk Factors in Addict Prisoners

    OpenAIRE

    AA Javadi; M Avijgan; M Hafizi

    2006-01-01

    High prevalence of HBV and HCV infections in prisoners suggests them as one of the main infection source in community. Preventive measures can possibly decrease their rate of infection and infectivity. We evaluated prevalence of HBV and HCV infections and their relation to dangerous behavior in addict prisoners. This was a cross-sectional study included prisoners of central provinces of Iran who were evaluated for HBV and HCV in 2003. All of 1431 prisoners filled out questionnaires that were ...

  7. Prevalence and characteristics of HIV/HBV and HIV/HCV coinfections in Tuscany

    Directory of Open Access Journals (Sweden)

    Monia Puglia

    2016-07-01

    Conclusions: We have observed less advanced disease in HIV and HCV-HIV patients compared with HBV–HIV coinfected patients. Moreover, our results show a higher prevalence of HIV/HCV among drug addicts and in the age-group 35–59, corresponding to those born in years considered most at risk for addiction. This study also confirms the finding of a less advanced HIV disease in HIV/HCV coinfected patients.

  8. HCV infection enhances Th17 commitment, which could affect the pathogenesis of autoimmune diseases.

    Directory of Open Access Journals (Sweden)

    Yasuteru Kondo

    Full Text Available Various kinds of autoimmune diseases have been reported to have a significant relationship with persistent hepatitis c virus (HCV infection and Th17 cells. Previously, our group reported that the existence of HCV in T lymphocytes could affect the development of CD4+ helper T cells and their proliferation, in addition to the induction of immunoglobulin hyper-mutation.Therefore, we analyzed the relationship between persistent infection of HCV and the mechanism of Th17 cell induction ex vivo and in vitro.The prevalence of autoimmune-related diseases in chronic hepatitis c patients (CH-C was significantly higher than in other types of chronic hepatitis (hepatitis B and NASH. A significantly higher frequency of IL6 and TGF-β double-high patients was detected in CH-C than in other liver diseases. Moreover, these double-high patients had significantly higher positivity of anti-nuclear antibody, cryoglobulinemia, and lymphotropic HCV and higher amounts of IL1-β, IL21, IL23. In addition to the previously reported lymphotropic SB-HCV strain, we found a novel, genotype 1b lymphotropic HCV (Ly-HCV, by deep sequencing analysis. Lymphotropic-HCV replication could be detected in the lymphoid cells with various kinds of cytokine-conditions including IL1β, IL23, IL6 and TGF-β in vitro. Infection by HCV could significantly enhance the development of Th17 cells. The HCV protein responsible for inducing the Th17 cells was HCV-Core protein, which could enhance the STAT-3 signaling and up-regulate the expression of RORγt as a Th17 master gene.Infection by lymphotropic HCV might enhance the Th17 development and contribute to understanding the pathogenesis of autoimmune-related diseases.

  9. HCV infection enhances Th17 commitment, which could affect the pathogenesis of autoimmune diseases.

    Science.gov (United States)

    Kondo, Yasuteru; Ninomiya, Masashi; Kimura, Osamu; Machida, Keigo; Funayama, Ryo; Nagashima, Takeshi; Kobayashi, Koju; Kakazu, Eiji; Kato, Takanobu; Nakayama, Keiko; Lai, Michael M C; Shimosegawa, Tooru

    2014-01-01

    Various kinds of autoimmune diseases have been reported to have a significant relationship with persistent hepatitis c virus (HCV) infection and Th17 cells. Previously, our group reported that the existence of HCV in T lymphocytes could affect the development of CD4+ helper T cells and their proliferation, in addition to the induction of immunoglobulin hyper-mutation. Therefore, we analyzed the relationship between persistent infection of HCV and the mechanism of Th17 cell induction ex vivo and in vitro. The prevalence of autoimmune-related diseases in chronic hepatitis c patients (CH-C) was significantly higher than in other types of chronic hepatitis (hepatitis B and NASH). A significantly higher frequency of IL6 and TGF-β double-high patients was detected in CH-C than in other liver diseases. Moreover, these double-high patients had significantly higher positivity of anti-nuclear antibody, cryoglobulinemia, and lymphotropic HCV and higher amounts of IL1-β, IL21, IL23. In addition to the previously reported lymphotropic SB-HCV strain, we found a novel, genotype 1b lymphotropic HCV (Ly-HCV), by deep sequencing analysis. Lymphotropic-HCV replication could be detected in the lymphoid cells with various kinds of cytokine-conditions including IL1β, IL23, IL6 and TGF-β in vitro. Infection by HCV could significantly enhance the development of Th17 cells. The HCV protein responsible for inducing the Th17 cells was HCV-Core protein, which could enhance the STAT-3 signaling and up-regulate the expression of RORγt as a Th17 master gene. Infection by lymphotropic HCV might enhance the Th17 development and contribute to understanding the pathogenesis of autoimmune-related diseases.

  10. Recent trends of Japanese hepatocellular carcinoma due to HCV in aging society.

    Science.gov (United States)

    Hiraoka, Atsushi; Hidaka, Satoshi; Shimizu, Yukou; Utsunomiya, Hiroki; Imai, Yusuke; Tatsukawa, Haruka; Tazuya, Nayu; Yamago, Hiroka; Yorimitsu, Nobukazu; Tanihira, Tetsuya; Hasebe, Aki; Miyamoto, Yasunao; Ninomiya, Tomoyuki; Kawasaki, Hideki; Hirooka, Masashi; Abe, Masanori; Hiasa, Yoichi; Matsuura, Bunzo; Onji, Morikazu; Michitaka, Kojiro

    2012-09-01

    The mean age of hepatocellular carcinoma (HCC) patients has increased (=65 years old). We want to identify the recent trend of the clinical features of HCC patients due to hepatitis C virus (HCV) (HCV-HCC). From 2000 to 2009, 855 naive HCC patients were admitted. HCV-HCC patients were divided into two groups, first period group (2000-04, n=270) and second period group (2005-09, n=343) and the clinical features of HCV-HCC were investigated. There was no difference in gender, TNM stage and percentages of HCV-HCC between the periods. On the other hand, the ratio of HCV-HCC patients with worse liver function (Child-Pugh B or C), elderly (=75 years old) and the population of patients treated with low invasive radiofrequency ablation were increased (30.0% to 42.0%, 17.2% to 35.8% and 25.1% to 36.2%, respectively; paged HCV-HCC as well as HCV-HCC patients with worse liver function was increased. The less invasive treatment for HCC in these patients and the quick anti-viral treatment for HCV patients should be considered to avoid occurrence of HCC in Japan.

  11. Active hepatitis C infection and HCV genotypes prevalent among the IDUs of Khyber Pakhtunkhwa

    Directory of Open Access Journals (Sweden)

    Uz Zaman Khaleeq

    2011-06-01

    Full Text Available Abstract Injection drug users (IDUs are considered as a high risk group to develop hepatitis C due to needle sharing. In this study we have examined 200 injection drug users from various regions of the Khyber Pakhtunkhwa province for the prevalence of active HCV infection and HCV genotypes by Immunochromatographic assays, RT-PCR and Type-specific PCR. Our results indicated that 24% of the IDUs were actively infected with HCV while anti HCV was detected among 31.5% cases. Prevalent HCV genotypes were HCV 2a, 3a, 4 and 1a. Majority of the IDUs were married and had attained primary or middle school education. 95% of the IDUs had a previous history of needle sharing. Our study indicates that the rate of active HCV infection among the IDUs is higher with comparatively more prevalence of the rarely found HCV types in KPK. The predominant mode of HCV transmission turned out to be needle sharing among the IDUs.

  12. Structural basis of hepatitis C virus neutralization by broadly neutralizing antibody HCV1

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Leopold; Giang, Erick; Robbins, Justin B.; Stanfield, Robyn L.; Burton, Dennis R.; Wilson, Ian A.; Law, Mansun (Scripps)

    2012-10-29

    Hepatitis C virus (HCV) infects more than 2% of the global population and is a leading cause of liver cirrhosis, hepatocellular carcinoma, and end-stage liver diseases. Circulating HCV is genetically diverse, and therefore a broadly effective vaccine must target conserved T- and B-cell epitopes of the virus. Human mAb HCV1 has broad neutralizing activity against HCV isolates from at least four major genotypes and protects in the chimpanzee model from primary HCV challenge. The antibody targets a conserved antigenic site (residues 412-423) on the virus E2 envelope glycoprotein. Two crystal structures of HCV1 Fab in complex with an epitope peptide at 1.8-{angstrom} resolution reveal that the epitope is a {beta}-hairpin displaying a hydrophilic face and a hydrophobic face on opposing sides of the hairpin. The antibody predominantly interacts with E2 residues Leu{sup 413} and Trp{sup 420} on the hydrophobic face of the epitope, thus providing an explanation for how HCV isolates bearing mutations at Asn{sup 415} on the same binding face escape neutralization by this antibody. The results provide structural information for a neutralizing epitope on the HCV E2 glycoprotein and should help guide rational design of HCV immunogens to elicit similar broadly neutralizing antibodies through vaccination.

  13. Phenotypic characterization of lymphocytes in HCV/HIV co-infected patients.

    LENUS (Irish Health Repository)

    Roe, Barbara

    2009-02-01

    While hepatitis C virus (HCV)-specific immune responses are attenuated in HCV\\/HIV co-infected patients compared to those infected with HCV alone, the reasons for this remain unclear. In this study, the proportions of regulatory, naïve, and memory T cells, along with chemokine receptor expression, were measured in co-infected and mono-infected patients to determine if there is an alteration in the phenotypic profile of lymphocytes in these patients. HCV\\/HIV co-infected patients had increased proportions of CD4(+) naïve cells and decreased proportions of CD4(+) effector cells when compared to HCV mono-infected patients. The proportions of CD4(+) Tregs and CD4(+) CXCR3(+) T cells were also significantly lower in co-infected patients. A decrease in CD4(+) Tregs and subsequent loss of immunosuppressive function may contribute to the accelerated progression to liver disease in co-infected individuals. Dysregulation of immune responses following reduction in the proportions of CD4(+) CXCR3(+) Th-1 cells may contribute to the reduced functional capacity of HCV-specific immune responses in co-infected patients. The findings of this study provide new information on the T-cell immunophenotype in HCV\\/HIV co-infected patients when compared to those infected with HCV alone, and may provide insight into why cell-mediated immune responses are diminished during HCV infection.

  14. Association of HCV with diabetes mellitus: an Egyptian case-control study

    Directory of Open Access Journals (Sweden)

    Esmat Gamal G

    2011-07-01

    Full Text Available Abstract Background The highest Hepatitis C Virus (HCV prevalence in the world occurs in Egypt. Several studies from different parts of the world have found that 13% to 33% of patients with chronic HCV have associated diabetes, mostly type II Diabetes Mellitus (DM. In Egypt the prevalence of DM is 25.4% among HCV patients. Therefore, it is important to identify the magnitude of the problem of diabetes in order to optimize the treatment of chronic hepatitis C. Methods The objective of this case-control study was to evaluate the prevalence of DM and other extrahepatic (EH manifestations among patients with different HCV morbidity stages including asymptomatic, chronic hepatic and cirrhotic patients. In this study, 289 HCV patients older than 18 were selected as cases. Also, 289 healthy controls were included. Laboratory investigations including Liver Function tests (LFT and blood glucose level were done. Also serological assays including cryoglobulin profile, rheumatoid factor, antinuclear antibody, HCV-PCR were performed. Results Out of 289 HCV cases, 40 (13.84% were diabetic. Out of 289 healthy controls, 12 (4.15% were diabetic. It was found that the diabetic HCV group mean age was [48.1 (± 9.2]. Males and urbanians represented 72.5% and 85% respectively. Lower level of education was manifested in 52.5% and 87.5% were married. In the nondiabetic HCV group mean age was [40.7 (± 10.4]. Males and urbanians represented 71.5% and 655% respectively. secondary and higher level of education was attained in 55.4% and 76.7% were married. Comparing between the diabetic HCV group and the non diabetic HCV group, age, residence and alcohol drinking were the only significant factors affecting the incidence of diabetes between the two groups. There was no significant difference regarding sonar findings although cirrhosis was more prevalent among diabetic HCV cases and the fibrosis score was higher in diabetic HCV patients than among the non diabetic HCV cases

  15. Multicenter evaluation of the Elecsys® anti-HCV II assay for the diagnosis of hepatitis C virus infection.

    Science.gov (United States)

    Esteban, Juan I; van Helden, Josef; Alborino, Flora; Bürgisser, Philippe; Cellerai, Cristina; Pantaleo, Giuseppe; Eiras, Adolfo; Rodriguez, Maria I; Ghisetti, Valeria; Gleich, Michael; Imdahl, Roland; Kaiser, Claudia; Möller, Petra; Wetlitzky, Olaf; Segovia, Manuel; Schennach, Harald; Mühlbacher, Annelies

    2013-08-01

    Routine screening of patients at risk of hepatitis C virus (HCV) infection has become a priority given recent improvements in therapeutic options and the asymptomatic nature of most chronic infections. The aim of this study was to evaluate the performance of the Elecsys® Anti-HCV II assay, a new qualitative antibody immunoassay, compared with currently available assays, and assess its suitability for routine diagnostic testing. The sensitivity of the Elecsys® Anti-HCV II, ARCHITECT® Anti-HCV, AxSYM® HCV 3.0, PRISM® HCV, Vitros® ECi Anti-HCV, Elecsys® Anti-HCV, and ADVIA Centaur® HCV assays was compared using commercially available seroconversion panels and samples from patients known to be HCV positive and infected with HCV genotypes 1-6. Specificity was investigated using samples from blood donors, unselected hospitalized patients, and patients with potential cross-reacting factors or from high-risk groups. The Elecsys® Anti-HCV II assay detected more positive bleeds than the comparator assays, was more sensitive in recognizing early HCV infection, and correctly identified all 765 samples known to be HCV positive, regardless of genotype. The overall specificity of the Elecsys(®) Anti-HCV II assay was 99.84% (n=6,850) using blood donor samples, 99.66% (n=3,922) using samples from unselected hospitalized patients, and 99.66% (n=2,397) using samples from patients with potentially cross-reacting factors or from high-risk groups. The specificity of the Elecsys® Anti-HCV II assay was superior or equal to the comparator assays. In conclusion, the Elecsys® Anti-HCV II assay is a sensitive and specific assay suitable for routine use in the reliable detection of anti-HCV antibodies. Copyright © 2013 Wiley Periodicals, Inc.

  16. Carbohydrate protease conjugates: Stabilized proteases for peptide synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Wartchow, C.A.; Wang, Peng; Bednarski, M.D.; Callstrom, M.R. [Ohio State Univ., Columbus, OH (United States)]|[Lawrence Berkeley Lab., CA (United States)

    1995-12-31

    The synthesis of oligopeptides using stable carbohydrate protease conjugates (CPCs) was examined in acetonitrile solvent systems. CPC[{alpha}-chymotrypsin] was used for the preparation of peptides containing histidine, phenylalanine, tryptophan in the P{sub 1} position in 60-93% yield. The CPC[{alpha}-chymotrypsin]-catalyzed synthesis of octamer Z-Gly-Gly-Phe-Gly-Gly-Phe-Gly-Gly-OEt from Z-Gly-Gly-Phe-Gly-Gly-Phe-OMe was achieved in 71% yield demonstrating that synthesis peptides containing both hydrophylic and hydrophobic amino acids. The P{sub 2} specificity of papain for aromatic residues was utilized for the 2 + 3 coupling of Z-Tyr-Gly-OMe to H{sub 2}N-Gly-Phe-Leu-OH to generate the leucine enkephalin derivative in 79% yield. Although papain is nonspecific for the hydrolysis of N-benzyloxycarbonyl amino acid methyl esters in aqueous solution, the rates of synthesis for these derivitives with nucleophile leucine tert-butyl ester differed by nearly 2 orders of magnitude. CPC[thermolysin] was used to prepare the aspartame precursor Z-Asp-Phe-OMe in 90% yield. The increased stability of CPCs prepared from periodate-modified poly(2-methacryl- amido-2-deoxy-D-glucose), poly(2-methacrylamido-2-deoxy-D-galactose), and poly(5-methacryl-amido-5-deoxy-D-ribose), carbohydrate materials designed to increase the aldehyde concentration in aqueous solution, suggests that the stability of CPCs is directly related to the aldehyde concentration of the carbohydrate material. Periodate oxidation of poly(2-methacrylamido-2-deoxy-D-glucose) followed by covalent attachment to {alpha}-chymotrypsin gave a CPC with catalytic activity in potassium phosphate buffer at 90{degrees}C for 2 h. 1 fig., 1 tab., 40 refs.

  17. Prevalence and impact of GBV-C, SEN-V and HBV occult infections in HIV-HCV co-infected patients on HCV therapy.

    Science.gov (United States)

    Piroth, Lionel; Carrat, Fabrice; Larrat, Sylvie; Goderel, Isabelle; Martha, Benoit; Payan, Christopher; Lunel-Fabiani, Françoise; Bani-Sadr, Firouze; Perronne, Christian; Cacoub, Patrice; Pol, Stanislas; Morand, Patrice

    2008-12-01

    It has been suggested that, in HIV-HCV co-infected patients, co-infections with other viruses may affect the response to HCV therapy. We aimed to assess the prevalence of GBV-C, SEN-V and occult HBV infections, their impact on HCV and HIV infections and on the response to HCV therapy in HIV-HCV co-infected patients. Three-hundred and sixty eight patients were tested before starting interferon-ribavirin for the presence of occult hepatitis B DNA, GBV-C RNA and SEN-V DNA by using real time PCR. Clinical, immunological, virological, histological characteristics and response to HCV therapy were compared according to the presence or not of each viral co-infection. HBV DNA, GBV-C RNA and SEN-V DNA were found in 5 (1.4%, CI95%: 0.2-2.4%), 104 (29.9%, CI95%: 25.1-34.7%) and 209 patients (57.9%, CI95%: 52.8-63.0%), respectively. GBV-C positive patients had significantly higher CD4 count at baseline, during and after HCV therapy, even after stratification on antiretroviral treatment. No other significant difference was observed according to the presence or not of GBV-C or SEN-V co-infection, in particular regarding virological responses to HCV combination therapy. There is no reason to withhold HCV therapy in HIV infected patients who have access to HAART, because of occult HBV, GBV-C or SEN-V co-infections.

  18. Socioeconomic status in HCV infected patients – risk and prognosis

    Directory of Open Access Journals (Sweden)

    Oml

    2013-05-01

    Full Text Available Lars Haukali Omland,1 Merete Osler,2 Peter Jepsen,3,4 Henrik Krarup,5 Nina Weis,6 Peer Brehm Christensen,7 Casper Roed,1 Henrik Toft Sørensen,3 Niels Obel1 On behalf of the DANVIR Cohort Study1Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; 2Research Center for Prevention and Health, Copenhagen University Hospital, Glostrup Hospital, Glostrup, Denmark; 3Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; 4Department of Medicine V (Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark; 5Department of Clinical Biochemistry, Aalborg Hospital, Aalborg, Denmark; 6Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre Hospital, Hvidovre, Denmark; 7Department of Infectious Diseases, Odense University Hospital, Odense, DenmarkBackground and aims: It is unknown whether socioeconomic status (SES is a risk factor for hepatitis C virus (HCV infection or a prognostic factor following infection.Methods: From Danish nationwide registries, we obtained information on three markers of SES: employment, income, and education. In a case control design, we examined HCV infected patients and controls; conditional logistic regression was employed to obtain odds ratios (ORs for HCV infection for each of the three SES markers, adjusting for the other two SES markers, comorbidity, and substance abuse. In a cohort design, we used Cox regression analysis to compute mortality rate ratios (MRRs for each of the three SES markers, adjusting for the other two SES markers, comorbidity level, age, substance abuse, and gender.Results: When compared to employed persons, ORs for HCV infection were 2.71 (95% confidence interval [CI]: 2.24–3.26 for disability pensioners and 2.24 (95% CI: 1.83–2.72 for the unemployed. When compared to persons with a high income, ORs were 1.64 (95% CI: 1.34–2.01 for low income persons and 1.19 (95% CI: 1.02–1.40 for

  19. Protease inhibitors targeting coronavirus and filovirus entry.

    Science.gov (United States)

    Zhou, Yanchen; Vedantham, Punitha; Lu, Kai; Agudelo, Juliet; Carrion, Ricardo; Nunneley, Jerritt W; Barnard, Dale; Pöhlmann, Stefan; McKerrow, James H; Renslo, Adam R; Simmons, Graham

    2015-04-01

    In order to gain entry into cells, diverse viruses, including Ebola virus, SARS-coronavirus and the emerging MERS-coronavirus, depend on activation of their envelope glycoproteins by host cell proteases. The respective enzymes are thus excellent targets for antiviral intervention. In cell culture, activation of Ebola virus, as well as SARS- and MERS-coronavirus can be accomplished by the endosomal cysteine proteases, cathepsin L (CTSL) and cathepsin B (CTSB). In addition, SARS- and MERS-coronavirus can use serine proteases localized at the cell surface, for their activation. However, it is currently unclear which protease(s) facilitate viral spread in the infected host. We report here that the cysteine protease inhibitor K11777, ((2S)-N-[(1E,3S)-1-(benzenesulfonyl)-5-phenylpent-1-en-3-yl]-2-{[(E)-4-methylpiperazine-1-carbonyl]amino}-3-phenylpropanamide) and closely-related vinylsulfones act as broad-spectrum antivirals by targeting cathepsin-mediated cell entry. K11777 is already in advanced stages of development for a number of parasitic diseases, such as Chagas disease, and has proven to be safe and effective in a range of animal models. K11777 inhibition of SARS-CoV and Ebola virus entry was observed in the sub-nanomolar range. In order to assess whether cysteine or serine proteases promote viral spread in the host, we compared the antiviral activity of an optimized K11777-derivative with that of camostat, an inhibitor of TMPRSS2 and related serine proteases. Employing a pathogenic animal model of SARS-CoV infection, we demonstrated that viral spread and pathogenesis of SARS-CoV is driven by serine rather than cysteine proteases and can be effectively prevented by camostat. Camostat has been clinically used to treat chronic pancreatitis, and thus represents an exciting potential therapeutic for respiratory coronavirus infections. Our results indicate that camostat, or similar serine protease inhibitors, might be an effective option for treatment of SARS and

  20. Prevention of HCV infection using a broad cross-neutralizing monoclonal antibody (AR4A) and Epigallocatechin-Gallate

    OpenAIRE

    O'Shea, D.; Law, J.; Egli, A.; Douglas, D.; Lund, G; Forester, S; Lambert, J.; Law, M; Burton, D R; Tyrrell, D. L. J.; Houghton, M; Humar, A; Kneteman, N.

    2016-01-01

    The anti-HCV activity of a novel monoclonal antibody (mAb; AR4A) and Epigallocatechin-gallate (EGCG) were studied in-vitro using an HCV cell culture system and in-vivo using a humanized liver mouse model capable of supporting HCV replication. Alone, both exhibit reliable cross-genotype HCV inhibition in-vitro, and combination therapy completely prevented HCV infection. In-vivo AR4A mAb (alone and combined with EGCG) robustly protects against the establishment of HCV genotype 1a infection. EGC...

  1. Daclatasvir Plus Asunaprevir for Chronic HCV Genotype 1b Infection

    Science.gov (United States)

    Kumada, Hiromitsu; Suzuki, Yoshiyuki; Ikeda, Kenji; Toyota, Joji; Karino, Yoshiyasu; Chayama, Kazuaki; Kawakami, Yoshiiku; Ido, Akio; Yamamoto, Kazuhide; Takaguchi, Koichi; Izumi, Namiki; Koike, Kazuhiko; Takehara, Tetsuo; Kawada, Norifumi; Sata, Michio; Miyagoshi, Hidetaka; Eley, Timothy; McPhee, Fiona; Damokosh, Andrew; Ishikawa, Hiroki; Hughes, Eric

    2014-01-01

    All-oral combinations of direct-acting antivirals may improve efficacy and safety outcomes for patients with hepatitis C virus (HCV) infection, particularly those who are poor candidates for current interferon/ribavirin-based regimens. In this open-label, phase 3 study, 135 interferon-ineligible/intolerant and 87 nonresponder patients with chronic HCV genotype 1b infection were enrolled at 24 centers in Japan. Patients received daclatasvir 60 mg once daily plus asunaprevir 100 mg twice daily for 24 weeks. The primary endpoint was sustained virologic response 24 weeks after treatment (SVR24). This study is registered with http://ClinicalTrials.gov (NCT01497834). SVR24 was achieved by 87.4% of interferon-ineligible/intolerant patients and 80.5% of nonresponder (null and partial) patients; rates were similar in cirrhosis (90.9%) and noncirrhosis (84.0%) patients, and in patients with IL28B CC (84.5%) or non-CC (84.8%) genotypes. Fourteen patients in each group (12.6%) discontinued dual therapy, mainly due to adverse events or lack of efficacy. Nine nonresponder patients received additional treatment with peginterferon/ribavirin per protocol-defined criteria. The rate of serious adverse events was low (5.9%) and varied among patients. The most common adverse events were nasopharyngitis, increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST), headache, diarrhea, and pyrexia. Conclusion: Interferon-free, ribavirin-free all-oral therapy with daclatasvir and asunaprevir for 24 weeks is well tolerated and can achieve a high rate of SVR in patients with HCV genotype 1b who were ineligible, intolerant, or had not responded to prior interferon-based therapy. (Hepatology 2014;59:2083–2091) PMID:24604476

  2. [siRNAs targeting La, hVAP-33, eIF2Bgamma, and HCV IRES inhibit the replication and expression of HCV in Huh7 cells].

    Science.gov (United States)

    Wang, Mei-xia; Xu, Bin; Duan, Jin; Fu, Xiao-qing; Jin, Ming

    2012-10-01

    To investigate the in vivo functional roles of the La autoantigen (La), the human homologue of the 33-kDa vesicle-associated membrane protein-associated protein (hVAP-33), and the subunit gamma of the human eukaryotic initiation factors 2B (eIF2Bgamma) as co-infection factors supporting chronic infection with hepatitis C virus (HCV). Small interfering (si)RNAs were designed against the HCV internal ribosome entry site (IRES) and transfected into Huh7 cells chronically infected with the HCV pseudovirus (designated as Huh7-HCV cells). The IRES siRNA producing the most effective silencing was selected for further analysis by fluorescence quantitative polymerase chain reaction (qPCR). siRNAs designed against La, hVAP-33, and eIF2Bgamma and the IRES-specific siRNA were then transfected, respectively or in various combinations, into the Huh7-HCV cell line for 48 h. The delta CT values were calculated and used to compare the HCV inhibitive efficacies of the siRNAs in isolation or in combination. Western blotting analysis was used to compare the quantity of core protein expression in each group. The four gene-specific siRNAs, in isolation or in combination, caused inhibition of HCV replication and gene and protein expressions to varying degrees. The combination of La + IRES siRNAs produced the strongest inhibition of HCV core antigen expression. The combinations of hVAP-33 + IRES siRNAs and eIF2Bgamma + IRES siRNAs produced stronger inhibitions of HCV replication and gene and protein expressions than either hVAP-33 siRNA or eIF2Bgamma siRNA alone. La, hVAP-33, and eIF2Bgamma act as co-infection factors of HCV chronic infection in vivo. HCV replication and gene and protein expression can be inhibited significantly by RNA interference of these co-infection factors and/or HCV IRES.

  3. Evaluation of proteases and protease inhibitors in Heterodera glycines cysts obtained from laboratory and field populations

    Science.gov (United States)

    Proteases and proteases inhibitors were evaluated in a number of preparations of Heterodera glycines cysts obtained from glasshouse cultures (GH) and field (LR) populations. Using a FRET-peptide library comprising 512 peptide substrate pools that detect 4 endoprotease types (aspartic, cysteine, meta...

  4. Purification and characterisation of a protease (tamarillin) from tamarillo fruit

    KAUST Repository

    Li, Zhao

    2018-02-16

    A protease from tamarillo fruit (Cyphomandra betacea Cav.) was purified by ammonium sulphate precipitation and diethylaminoethyl-Sepharose chromatography. Protease activity was determined on selected peak fractions using a casein substrate. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis showed that the peak with the highest protease activity consisted of one protein of molecular mass ca. 70 kDa. The protease showed optimal activity at pH 11 and 60°C. It was sensitive to phenylmethylsulphonyl fluoride while ethylenediaminetetraacetic acid and p-chloromercuribenzoic acid had little effect on its activity, indicating that this enzyme was a serine protease. Hg2+ strongly inhibited enzyme activity, possibly due to formation of mercaptide bonds with the thiol groups of the protease, suggesting that some cysteine residues may be located close to the active site. De novo sequencing strongly indicated that the protease was a subtilisin-like alkaline serine protease. The protease from tamarillo has been named \\'tamarillin\\'.

  5. Metabolic and Cardiovascular Complications in HIV/HCV-Co-infected Patients.

    Science.gov (United States)

    Bedimo, Roger; Abodunde, Oladapo

    2016-12-01

    Fifteen to thirty percent of HIV-infected persons in North America and Europe are co-infected with chronic hepatitis C (HCV). The latter is associated with a significant number of extra-hepatic metabolic complications that could compound HIV-associated increased cardiovascular risk. This article reviews the basic science and epidemiologic and clinical evidence for increased cardio-metabolic risk among HIV/HCV-co-infected patients and discusses potential underlying mechanisms. We will finally review the impact of control of HCV viremia on the cardio-metabolic morbidity and mortality of HIV/HCV-co-infected patients. HCV infection is associated with a number of immune-related complications such as cryoglobulinemia but also metabolic complications including dyslipidemias, hepatic steatosis, insulin resistance, diabetes, and chronic kidney disease. The incidence of these complications is higher among HIV-co-infected patients and might contribute to increased mortality. The potential mechanisms of increased cardiovascular risk among HIV/HCV-co-infected subjects include endothelial dysfunction, chronic inflammation and immune activation, the cardio-metabolic effects of HCV-induced hepatic steatosis and fibrosis or insulin resistance, and chronic kidney disease. However, epidemiologic studies show discordant findings as to whether HCV co-infection further increases the risk of atherosclerotic cardiovascular diseases (acute myocardial infarctions and strokes) among HIV-infected patients. Nonetheless, successful treatment of HCV is associated with significant improvements in cardio-metabolic risk factors including diabetes mellitus. HCV co-infection is associated with a higher incidence of metabolic complications-and likely increased risk of cardiovascular events-that might contribute to increased mortality in HIV. These appear to improve with successful HCV therapy.

  6. HCV antibody quantitative levels in liver transplant patients: do they have any relevance in clinical practice?

    Science.gov (United States)

    Jain, Ashok; Menegus, Marilyn; Mohanka, Ravi; Orloff, Mark; Abt, Peter; Mantry, Parvez; Bozorgzadeh, Adel

    2006-06-01

    Hepatitis C virus (HCV) is not directly cytopathic to the hepatocytes; however, host immune response against the virus does cause hepatic injury. Production of the HCV antibody is a host immune response to a viral antigen. The currently used HCV antibody assay is a qualitative, not quantitative, assessment. In this study, we sought to quantitatively estimate HCV antibody levels in patients who had undergone liver transplantations at the University of Rochester Medical Center, Rochester, New York, and correlate these levels with HCV RNA viral load, genotype, severity of recurrence, and anti-HCV treatment. From 39 liver transplantation patients, we obtained 141 blood samples for quantitative HCV RNA to measure HCV antibody levels quantitatively. Most antibody levels were within a narrow range with a mean of 32.9+/-5.1. Samples with undetectable RNA had a mean antibody level of 31.4+/-8.0, and samples with a positive RNA had mean level of 33.0+/-4.6. The mean antibody levels were significantly higher for patients with genotype 1 (n=33) compared with those with genotype 2 (n=5) (33.2 vs 29.1; P=.007). No correlation was found between antibody levels and severity of hepatic injury with regard to hepatitis activity index or fibrosis score. Six patients with no response to anti-HCV treatment had no change in their mean antibody levels (33.7 vs 34.5). Ten patients who responded to anti-HCV therapy had lower mean levels after therapy, but the changes were not significant (34.2 vs 30.4). Antibody levels in this study did not correlate with viral load or hepatic injury. However, genotype-2 patients had significantly lower levels compared with genotype-1 patients, and patients who responded to anti-HCV therapy demonstrated decreased antibody levels.

  7. Temporal Proteomics of Inducible RNAi Lines of Clp Protease Subunits Identifies Putative Protease Substrates.

    Science.gov (United States)

    Moreno, Juan C; Martínez-Jaime, Silvia; Schwartzmann, Joram; Karcher, Daniel; Tillich, Michael; Graf, Alexander; Bock, Ralph

    2018-02-01

    The Clp protease in the chloroplasts of plant cells is a large complex composed of at least 13 nucleus-encoded subunits and one plastid-encoded subunit, which are arranged in several ring-like structures. The proteolytic P-ring and the structurally similar R-ring form the core complex that contains the proteolytic chamber. Chaperones of the HSP100 family help with substrate unfolding, and additional accessory proteins are believed to assist with Clp complex assembly and/or to promote complex stability. Although the structure and function of the Clp protease have been studied in great detail in both bacteria and chloroplasts, the identification of bona fide protease substrates has been very challenging. Knockout mutants of genes for protease subunits are of limited value, due to their often pleiotropic phenotypes and the difficulties with distinguishing primary effects (i.e. overaccumulation of proteins that represent genuine protease substrates) from secondary effects (proteins overaccumulating for other reasons). Here, we have developed a new strategy for the identification of candidate substrates of plant proteases. By combining ethanol-inducible knockdown of protease subunits with time-resolved analysis of changes in the proteome, proteins that respond immediately to reduced protease activity can be identified. In this way, secondary effects are minimized and putative protease substrates can be identified. We have applied this strategy to the Clp protease complex of tobacco ( Nicotiana tabacum ) and identified a set of chloroplast proteins that are likely degraded by Clp. These include several metabolic enzymes but also a small number of proteins involved in photosynthesis. © 2018 American Society of Plant Biologists. All Rights Reserved.

  8. Temporal Proteomics of Inducible RNAi Lines of Clp Protease Subunits Identifies Putative Protease Substrates1[OPEN

    Science.gov (United States)

    Martínez-Jaime, Silvia; Karcher, Daniel; Tillich, Michael

    2018-01-01

    The Clp protease in the chloroplasts of plant cells is a large complex composed of at least 13 nucleus-encoded subunits and one plastid-encoded subunit, which are arranged in several ring-like structures. The proteolytic P-ring and the structurally similar R-ring form the core complex that contains the proteolytic chamber. Chaperones of the HSP100 family help with substrate unfolding, and additional accessory proteins are believed to assist with Clp complex assembly and/or to promote complex stability. Although the structure and function of the Clp protease have been studied in great detail in both bacteria and chloroplasts, the identification of bona fide protease substrates has been very challenging. Knockout mutants of genes for protease subunits are of limited value, due to their often pleiotropic phenotypes and the difficulties with distinguishing primary effects (i.e. overaccumulation of proteins that represent genuine protease substrates) from secondary effects (proteins overaccumulating for other reasons). Here, we have developed a new strategy for the identification of candidate substrates of plant proteases. By combining ethanol-inducible knockdown of protease subunits with time-resolved analysis of changes in the proteome, proteins that respond immediately to reduced protease activity can be identified. In this way, secondary effects are minimized and putative protease substrates can be identified. We have applied this strategy to the Clp protease complex of tobacco (Nicotiana tabacum) and identified a set of chloroplast proteins that are likely degraded by Clp. These include several metabolic enzymes but also a small number of proteins involved in photosynthesis. PMID:29229697

  9. Intracellular proteases of Bacillus thuringiensis subsp. kurstaki and a protease-deficient mutant Btk-q.

    Science.gov (United States)

    Reddy, Y Chandrahasa; Venkateswerlu, G

    2002-12-01

    The commencement of intracellular protease synthesis was studied by gelatin zymography in Bacillus thuringiensis ( Btk) HD1, Btk HD73, and a protease-deficient mutant Btk-q derived from the former strain. By gelatin zymography, a 92-kDa protease was detected first at 3 h of sporulation, which continued until 48 h, whereas two other proteases of mol wt 78 and 69 kDa were detectable from 6 h onwards and continued until 48 h of growth in Btk HD1. Similar studies revealed the presence of two major intracellular proteases in Btk HD73 by gelatin zymography, which first appeared at 6 h of sporulation and continued until 48 h of growth. The quantitative azocasein assay confirmed that the total protease activity increases from 3 to 21 h, thereafter reaching a plateau up to 48 h of growth examined, in HD1 and HD73 strains. Btk-q, a protease-deficient mutant, showed traces of protease activity by azocasein analysis that could not be detected by gelatin zymography. The free amino acid pool content was also increased parallel to the way that the protease activity increased in all three strains. However, this increase was found to be low (16-fold) in Btk-q when compared with Btk HD1 and HD73 strains. The following amino acids were detected by paper chromatography in Btk HD1: DL-alanine, L-glutamic acid, L-aspartic acid, tyrosine, tryptophan/methionine/valine, arginine, leucine/norleucine/isoleucine, and glycine, whereas only DL-alanine, L-glutamic acid, and L-aspartic acid were in Btk-q at 24 and 48 h, when the protease activity was maximum.

  10. High throughput in vivo protease inhibitor selection platform

    DEFF Research Database (Denmark)

    2017-01-01

    The invention relates to a recombinant microbial cell comprising a selection platform for screening for a protease inhibitor, wherein the platform comprises transgenes encoding a protease having selective peptide bond cleavage activity at a recognition site amino acid sequence; and transgenes...... encoding polypeptides conferring resistance to microbial growth inhibitors; wherein the polypeptides comprise the recognition site amino acid sequence cleavable by the protease. Protease inhibitors are detected by their ability to inhibit protease specific cleavage and inactivation of the polypeptides...... platform for screening for a protease inhibitor....

  11. Rapid virological response of telaprevir and boceprevir in a Brazilian cohort of HCV genotype 1 patients: a multicenter longitudinal study

    Directory of Open Access Journals (Sweden)

    Borba HHL

    2017-01-01

    Full Text Available Helena HL Borba,1 Astrid Wiens,1 Laiza M Steimbach,1 Fernanda S Tonin,1 Maria LA Pedroso,2 Cláudia AP Ivantes,3 Fernando Fernandez-Llimos,4 Roberto Pontarolo1 1Pharmaceutical Sciences Postgraduate Research Program, Department of Pharmacy, 2Gastroenterology Service, Hospital de Clínicas, Federal University of Paraná, 3Guidance and Counseling Center, Curitiba City Hall, Curitiba, Paraná, Brazil; 4Department of Social Pharmacy, Faculty of Pharmacy, Research Institute for Medicines, University of Lisboa, Lisbon, Portugal Background: Chronic hepatitis C is a major public health issue, but there is a gap in the literature regarding the effectiveness and safety of direct-acting antiviral agents in the Brazilian population. The main aim of this study was to describe the effectiveness of boceprevir and telaprevir in patients treated at public health care institutions in Brazil.Materials and methods: A prospective longitudinal and multicenter study was conducted in five centers in the State of Paraná between September 2014 and June 2016. Data regarding effectiveness and safety were collected from medical records of patients treated with boceprevir or telaprevir. The effectiveness outcome comprised the rapid virological response (RVR. Multivariate analysis was performed to verify the influence of independent variables (ie, age, gender, baseline viral load on RVR achievement.Results: Data were collected from 117 patients with chronic hepatitis C virus (HCV genotype 1 infection. Fifteen patients received treatment with boceprevir and 102 received telaprevir. The mean age was 51.6 years, 64.1% were male, 44.4% were infected with HCV subtype 1a, 62.4% had a high baseline viral load (≥800,000 IU/mL and 33% were cirrhotic. Furthermore, 79.5% of patients achieved RVR (26.7% in the boceprevir group and 87.3% in the telaprevir group. Multivariate analysis demonstrated that the type of protease inhibitor (boceprevir or telaprevir and the baseline viral load

  12. Prevalence of natural polymorphisms at the HCV NS5A gene associated with resistance to daclatasvir, an NS5A inhibitor.

    Science.gov (United States)

    Plaza, Zulema; Soriano, Vincent; Vispo, Eugenia; del Mar Gonzalez, Maria; Barreiro, Pablo; Seclén, Eduardo; Poveda, Eva

    2012-01-01

    Daclatasvir (BMS-790052) is an investigational molecule that inhibits the HCV NS5A protein and shows potent antiviral activity apparently across all HCV genotypes. Selection of drug resistance mutations has been reported only for HCV genotype 1, and no information exists for other HCV variants and/or in HIV-HCV-coinfected individuals. All interferon-α-naive, HIV-HCV-coinfected patients newly attended at Hospital Carlos III (Madrid, Spain) in 2011 were identified. Changes reported to be associated with daclatasvir resistance in the in vitro replication system for HCV genotype/subtypes 1a/1b (M28T, Q30H/R, L31F/M/V, P32L and Y93C/H/N) were examined. A total of 78 HIV-HCV-coinfected individuals as well as 635 NS5A sequences deposited at Los Alamos HCV database were analysed. None of the NS5A sequences from HCV-1a or HCV-3 showed changes associated with daclatasvir resistance. By contrast, all NS5A sequences from HCV-4 harboured L31M. The double mutant L31M+Y93H was found in 7% of HCV-1b and 13% of HCV-4. Finally, all NS5A sequences from HCV-1b and HCV-4 harboured changes at codon 28 (M28L) and 30 (L30R), which are of unknown significance. The rate of all these NS5A polymorphisms did not differ significantly when comparing HIV-HCV-coinfected patients and sequences from HCV-monoinfected subjects deposited at Los Alamos HCV database. Primary resistance mutations to daclatasvir, an investigational HCV NS5A inhibitor, are not seen in HCV-1a or in HCV-3 as natural polymorphisms. By contrast, they can be recognized in most HCV-1b and HCV-4 strains, regardless HIV coinfection.

  13. Protease Inhibitors from Plants with Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Yoonkyung Park

    2009-06-01

    Full Text Available Antimicrobial proteins (peptides are known to play important roles in the innate host defense mechanisms of most living organisms, including plants, insects, amphibians and mammals. They are also known to possess potent antibiotic activity against bacteria, fungi, and even certain viruses. Recently, the rapid emergence of microbial pathogens that are resistant to currently available antibiotics has triggered considerable interest in the isolation and investigation of the mode of action of antimicrobial proteins (peptides. Plants produce a variety of proteins (peptides that are involved in the defense against pathogens and invading organisms, including ribosome-inactivating proteins, lectins, protease inhibitors and antifungal peptides (proteins. Specially, the protease inhibitors can inhibit aspartic, serine and cysteine proteinases. Increased levels of trypsin and chymotrypsin inhibitors correlated with the plants resistance to the pathogen. Usually, the purification of antimicrobial proteins (peptides with protease inhibitor activity was accomplished by salt-extraction, ultrafiltration and C18 reverse phase chromatography, successfully. We discuss the relation between antimicrobial and anti-protease activity in this review. Protease inhibitors from plants potently inhibited the growth of a variety of pathogenic bacterial and fungal strains and are therefore excellent candidates for use as the lead compounds for the development of novel antimicrobial agents.

  14. 77 FR 30293 - Recommendations for the Identification of Hepatitis C Virus (HCV) Chronic Infection

    Science.gov (United States)

    2012-05-22

    ... Hepatitis C Virus (HCV) Chronic Infection AGENCY: Centers for Disease Control and Prevention (CDC... an email to [email protected] . SUPPLEMENTARY INFORMATION: Hepatitis C virus infection is a contagious... illness. It results from infection with the hepatitis C virus (HCV), which is spread primarily through...

  15. Prevalence of anti HCV infection in patients with beta-thalassemia in Isfahan-Iran

    Directory of Open Access Journals (Sweden)

    Behrooz Ataei

    2012-01-01

    Conclusions: Our findings revealed that blood transfusion was the main risk factors for HCV infection among beta-thalassemic patients. Therefore, more blood donor screening programs and effective screening techniques are needed to prevent transmission of HCV infection among beta-thalassemic patients.