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Hassan M, Selimovic D, El-Khattouti A, Ghozlan H, Haikel Y, Abdelkader O. Hepatitis C virus-host interactions: Etiopathogenesis and therapeutic strategies. World J Exp Med 2012; 2:7-25. [PMID: 24520529 PMCID: PMC3905577 DOI: 10.5493/wjem.v2.i2.7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 04/16/2012] [Accepted: 04/18/2012] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a significant health problem facing the world. This virus infects more than 170 million people worldwide and is considered the major cause of both acute and chronic hepatitis. Persons become infected mainly through parenteral exposure to infected material by blood transfusions or injections with nonsterile needles. Although the sexual behavior is considered as a high risk factor for HCV infection, the transmission of HCV infection through sexual means, is less frequently. Currently, the available treatment for patients with chronic HCV infection is interferon based therapies alone or in combination with ribavirin and protease inhibitors. Although a sustained virological response of patients to the applied therapy, a great portion of patients did not show any response. HCV infection is mostly associated with progressive liver diseases including fibrosis, cirrhosis and hepatocellular carcinoma. Although the focus of many patients and clinicians is sometimes limited to that problem, the natural history of HCV infection (HCV) is also associated with the development of several extrahepatic manifestations including dermatologic, rheumatologic, neurologic, and nephrologic complications, diabetes, arterial hypertension, autoantibodies and cryglobulins. Despite the notion that HCV-mediated extrahepatic manifestations are credible, the mechanism of their modulation is not fully described in detail. Therefore, the understanding of the molecular mechanisms of HCV-induced alteration of intracellular signal transduction pathways, during the course of HCV infection, may offer novel therapeutic targets for HCV-associated both hepatic and extrahepatic manifestations. This review will elaborate the etiopathogenesis of HCV-host interactions and summarize the current knowledge of HCV-associated diseases and their possible therapeutic strategies.
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Affiliation(s)
- Mohamed Hassan
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
| | - Denis Selimovic
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
| | - Abdelouahid El-Khattouti
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
| | - Hanan Ghozlan
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
| | - Youssef Haikel
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
| | - Ola Abdelkader
- Mohamed Hassan, Denis Selimovic, Youssef Haikel, National Institute of Health and Medical Research, U 977, Faculty of Medicine, and Dental Faculty, 11 Rue Humann, 67085 Strasbourg Cedex, France
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Raychoudhuri A, Shrivastava S, Steele R, Kim H, Ray R, Ray RB. ISG56 and IFITM1 proteins inhibit hepatitis C virus replication. J Virol 2011; 85:12881-9. [PMID: 21976647 PMCID: PMC3233139 DOI: 10.1128/jvi.05633-11] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 09/28/2011] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) often leads to persistent infection. Interferon (IFN) and IFN-stimulated genes (ISGs) are amplified during HCV infection but fail to eliminate virus from the liver in a large number of infected patients. We have observed previously that HCV infection induces IFN-β production in immortalized human hepatocytes (IHH) as early as 24 h after infection, although virus replication is not inhibited. To gain insights on possible countermeasures of virus for the suppression of host antiviral response, the cellular transcriptional profiles of ISGs were examined after various treatments of IHH. The majority of ISGs were upregulated in IFN-treated IHH from the level for mock-treated cells. However, the comparison of ISG expression in IFN-treated IHH and IFN-pretreated, HCV genotype 2a-infected IHH indicated that virus infection suppresses the upregulation of a subset of effector molecules, including ISG56 and IFITM1. Similar results were observed for HCV-infected Huh7 cells. Subsequent study suggested that the exogenous expression of ISG56 or IFITM1 inhibits HCV replication in IHH or Huh7 cells, and the knockdown of these genes enhanced HCV replication. Further characterization revealed that the overexpression of these ISGs does not block HCV pseudotype entry into Huh7 cells. Taken together, our results demonstrated that ISG56 and IFITM1 serve as important molecules to restrict HCV infection, and they may have implications in the development of therapeutic modalities.
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Affiliation(s)
| | | | | | - Hangeun Kim
- Internal Medicine, Saint Louis University, St. Louis, Missouri
| | - Ranjit Ray
- Internal Medicine, Saint Louis University, St. Louis, Missouri
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3
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Abstract
Hepatitis C virus (HCV) infection in humans can cause progressive and end-stage liver disease. As such, preventive measures against HCV, including vaccine development, are a priority among researchers in the field. The report from Garrone et al. describes the development of a vaccine platform to generate HCV-neutralizing antibodies that are based on retrovirus-derived virus-like particles (VLPs) pseudotyped with heterologous viral envelope proteins. Immunization with these VLPs induced neutralizing antibodies in mouse and macaque models. These results, when considered in the context of an earlier clinical trial that used recombinant HCV E1/E2 purified protein as a subunit vaccine and additional findings from the VLP strategy, may lead to a new HCV vaccine that induces a neutralizing antibody response.
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Affiliation(s)
- Ranjit Ray
- Department of Internal Medicine, Saint Louis University, Saint Louis, MO 63104, USA.
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Mazumdar B, Banerjee A, Meyer K, Ray R. Hepatitis C virus E1 envelope glycoprotein interacts with apolipoproteins in facilitating entry into hepatocytes. Hepatology 2011; 54:1149-56. [PMID: 21735466 PMCID: PMC3184191 DOI: 10.1002/hep.24523] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 06/17/2011] [Indexed: 12/20/2022]
Abstract
UNLABELLED Our previous studies demonstrated that hepatitis C virus (HCV) envelope glycoproteins 1 and 2 (E1 and E2) display distinct reactivity to different cell-surface molecules. In this study, we characterized the interaction of E1 and E2 with apolipoproteins in facilitating virus entry. The results suggested a higher neutralization of vesicular stomatitis virus (VSV)/HCV E1-G pseudotype infectivity by antibodies to apolipoprotein E (ApoE) than apolipoprotein B (ApoB), with VSV/HCV E2-G pseudotype infectivity remaining largely unaffected. Neutralization of cell-culture-grown HCV infectivity by antiserum to ApoE and, to a lesser extent, by ApoB further verified their involvement in virus entry. HCV E1, but not E2, displayed binding with ApoE and ApoB by enzyme-linked immunosorbent assay. Binding of E1 with apolipoproteins were further supported by coimmunoprecipitation from human hepatocytes expressing E1. Rabbit antiserum to a selected E1 ectodomain-derived peptide displayed ∼ 50% neutralization of E1-G pseudotype infectivity. Furthermore, E1 ectodomain-derived synthetic peptides significantly inhibited the interaction of E1 with both the apolipoproteins. Investigation on the role of low-density lipoprotein receptor (LDL-R) as a hepatocyte surface receptor for virus entry suggested a significant reduction in E1-G pseudotype plaque numbers (∼ 70%) by inhibiting LDL-R ligand-binding activity using human proprotein convertase subtilisin/kexin type 9 and platelet factor-4, whereas they had a minimal inhibitory effect on the E2-G pseudotype. CONCLUSION Together, the results suggested an association between HCV E1 and apolipoproteins, which may facilitate virus entry through LDL-R into mammalian cells.
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Affiliation(s)
| | - Arup Banerjee
- Department of Internal Medicine, Saint Louis University, Missouri
| | - Keith Meyer
- Department of Internal Medicine, Saint Louis University, Missouri
| | - Ranjit Ray
- Department of Internal Medicine, Saint Louis University, Missouri
- Department of Molecular Microbiology and Immunology, Saint Louis University, Missouri
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A weak neutralizing antibody response to hepatitis C virus envelope glycoprotein enhances virus infection. PLoS One 2011; 6:e23699. [PMID: 21887300 PMCID: PMC3161815 DOI: 10.1371/journal.pone.0023699] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2011] [Accepted: 07/22/2011] [Indexed: 01/26/2023] Open
Abstract
We have completed a phase 1 safety and immunogenicity trial with hepatitis C virus (HCV) envelope glycoproteins, E1 and E2, with MF59 adjuvant as a candidate vaccine. Neutralizing activity to HCV genotype 1a was detected in approximately 25% of the vaccinee sera. In this study, we evaluated vaccinee sera from poor responders as a potential source of antibody dependent enhancement (ADE) of HCV infection. Sera with poor neutralizing activity enhanced cell culture grown HCV genotype 1a or 2a, and surrogate VSV/HCV pseudotype infection titer, in a dilution dependent manner. Surrogate pseudotypes generated from individual HCV glycoproteins suggested that antibody to the E2 glycoprotein; but not the E1 glycoprotein, was the principle target for enhancing infection. Antibody specific to FcRII expressed on the hepatic cell surface or to the Fc portion of Ig blocked enhancement of HCV infection by vaccinee sera. Together, the results from in vitro studies suggested that enhancement of viral infectivity may occur in the absence of a strong antibody response to HCV envelope glycoproteins.
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Banerjee A, Ray RB, Ray R. Oncogenic potential of hepatitis C virus proteins. Viruses 2010; 2:2108-2133. [PMID: 21994721 PMCID: PMC3185750 DOI: 10.3390/v2092108] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 09/23/2010] [Accepted: 09/24/2010] [Indexed: 02/06/2023] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a major risk factor for liver disease progression, and may lead to cirrhosis and hepatocellular carcinoma (HCC). The HCV genome contains a single-stranded positive sense RNA with a cytoplasmic lifecycle. HCV proteins interact with many host-cell factors and are involved in a wide range of activities, including cell cycle regulation, transcriptional regulation, cell proliferation, apoptosis, lipid metabolism, and cell growth promotion. Increasing experimental evidences suggest that HCV contributes to HCC by modulating pathways that may promote malignant transformation of hepatocytes. At least four of the 10 HCV gene products, namely core, NS3, NS5A and NS5B play roles in several potentially oncogenic pathways. Induction of both endoplasmic reticulum (ER) stress and oxidative stress by HCV proteins may also contribute to hepatocyte growth promotion. The current review identifies important functions of the viral proteins connecting HCV infections and potential for development of HCC. However, most of the putative transforming potentials of the HCV proteins have been defined in artificial cellular systems, and need to be established relevant to infection and disease models. The new insight into the mechanisms for HCV mediated disease progression may offer novel therapeutic targets for one of the most devastating human malignancies in the world today.
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Affiliation(s)
- Arup Banerjee
- Department of Internal Medicine, Edward A. Doisy Research Center, 1100 S. Grand Blvd., 8th Floor, St. Louis, MO 63104, USA; E-Mail:
| | - Ratna B. Ray
- Department of Pathology, Edward A. Doisy Research Center, 1100 S. Grand Blvd., 2nd Floor, St. Louis, MO 63104, USA; E-Mail:
| | - Ranjit Ray
- Department of Internal Medicine, Edward A. Doisy Research Center, 1100 S. Grand Blvd., 8th Floor, St. Louis, MO 63104, USA; E-Mail:
- Molecular Microbiology & Immunology, Edward A. Doisy Research Center, 1100 S. Grand Blvd., 8th Floor, St. Louis, MO 63104, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: 1-314- 977-9034; Fax: 1-314-771-3816
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Ray R, Meyer K, Banerjee A, Basu A, Coates S, Abrignani S, Houghton M, Frey SE, Belshe RB. Characterization of antibodies induced by vaccination with hepatitis C virus envelope glycoproteins. J Infect Dis 2010; 202:862-6. [PMID: 20677942 PMCID: PMC2931414 DOI: 10.1086/655902] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Hepatitis C virus (HCV) envelope glycoproteins E1 and E2 were used with MF59 adjuvant as a candidate vaccine for a phase 1 safety and immunogenicity trial. Ten of 41 vaccinee serum samples displayed a neutralization titer of ⩾1:20 against vesicular stomatitis virus (VSV)-HCV pseudotype, 15 of 36 serum samples tested had a neutralization titer of ⩾1:400 against human immunodeficiency virus (HIV)-HCV pseudotype, and 10 of 36 serum samples tested had a neutralization titer of ⩾1:20 against cell culture-grown HCV genotype 1a. Neutralizing serum samples had increased affinity levels and displayed >2-fold higher specific activity levels to well-characterized epitopes on E1/E2, especially to the hypervariable region 1 of E2.
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Affiliation(s)
- Ranjit Ray
- Department of Internal Medicine and Vaccine and Treatment Evaluation Unit, Saint Louis University, St. Louis, Missouri, USA.
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Frey SE, Houghton M, Coates S, Abrignani S, Chien D, Rosa D, Pileri P, Ray R, Di Bisceglie AM, Rinella P, Hill H, Wolff MC, Schultze V, Han JH, Scharschmidt B, Belshe RB. Safety and immunogenicity of HCV E1E2 vaccine adjuvanted with MF59 administered to healthy adults. Vaccine 2010; 28:6367-73. [PMID: 20619382 DOI: 10.1016/j.vaccine.2010.06.084] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 06/17/2010] [Accepted: 06/25/2010] [Indexed: 12/12/2022]
Abstract
BACKGROUND Hepatitis C virus (HCV) causes chronic liver disease that often leads to cirrhosis and hepatocellular carcinoma. In animal studies, chimpanzees were protected against chronic infection following experimental challenge with either homologous or heterologous HCV genotype 1a strains which predominate in the USA and Canada. We describe the first in humans clinical trial of this prophylactic HCV vaccine. METHODS HCV E1E2 adjuvanted with MF59C.1 (an oil-in-water emulsion) was given at 3 different dosages on day 0 and weeks 4, 24 and 48 in a phase 1, placebo-controlled, dose escalation trial to healthy HCV-negative adults. RESULTS There was no significant difference in the proportion of subjects reporting adverse events across the groups. Following vaccination subjects developed antibodies detectable by ELISA, CD81 neutralization and VSV/HCV pseudotype neutralization. There were no significant differences between vaccine groups in the number of responders and geometric mean titers for each of the three assays. All subjects developed lymphocyte proliferation responses to E1E2 and an inverse response to increasing amounts of antigen was noted. CONCLUSIONS The vaccine was safe and generally well-tolerated at each of the 3 dosage levels and induced antibody and lymphoproliferative responses. A larger study to further evaluate safety and immunogenicity is warranted.
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Affiliation(s)
- Sharon E Frey
- Saint Louis University School of Medicine, Division of Infectious Diseases and Immunology, St. Louis, MO 63104, USA.
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9
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Expression and structural properties of a chimeric protein based on the ectodomains of E1 and E2 hepatitis C virus envelope glycoproteins. Protein Expr Purif 2010; 71:123-31. [DOI: 10.1016/j.pep.2010.02.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 02/16/2010] [Accepted: 02/16/2010] [Indexed: 12/19/2022]
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Fafi-Kremer S, Zeisel MB, Schvoerer E, Soulier E, Habersetzer F, Wolf P, Doffoel M, Baumert TF, Stoll-Keller F. [Neutralizing antibodies in hepatitis C virus infection]. ACTA ACUST UNITED AC 2008; 32:491-8. [PMID: 18467058 DOI: 10.1016/j.gcb.2008.02.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 01/29/2008] [Accepted: 02/29/2008] [Indexed: 01/12/2023]
Abstract
Hepatitis C virus (HCV) results in persistent infection in more than 70% of infected individuals despite the development of humoral and cellular immune responses. Following infection, although antibodies targeting epitopes of both structural and non structural proteins are elicited, the virus evades antibody-mediated neutralization. Studies of host neutralizing responses against HCV have been limited by the lack of a convenient tissue culture system for HCV infection. In the past five years in vitro models have been developed to characterize interaction of HCV glycoproteins with host cell entry factors and detect antibodies interfering with HCV entry and infection. These models have been used to characterize targets of neutralizing responses and better understand their impact on the pathogenesis of infection.
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Affiliation(s)
- S Fafi-Kremer
- Laboratoire de virologie, Inserm U748, 3, rue Koeberlé, 67000 Strasbourg, France
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11
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Abstract
Hepatitis C virus (HCV) often causes a persistent infection associated with hypergammaglobulinemia, high levels of antiviral antibody and circulating immune complexes, and immune complex disease. We previously reported that only a limited neutralizing activity to vesicular stomatitis virus or HCV pseudotype is generated in animals immunized with recombinant HCV envelope proteins and chronically infected HCV patient sera. Interestingly, when some of these neutralizing sera were diluted into a range of concentrations below those that reduced virus plaque number, an increase in pseudotype plaque formation was observed. Purified HCV E2-specific human monoclonal antibodies were used to further verify the specificity of this enhancement, and one- to twofold increases were apparent on permissive Huh-7 cells. The enhancement of HCV pseudotype titer could be inhibited by the addition of a Fc-specific anti-human immunoglobulin G Fab fragment to the virus-antibody mixture prior to infection. Treatment of cells with antibody to Fc receptor I (FcRI) or FcRII, but not FcRIII, also led to an inhibition of pseudotype titer enhancement in an additive manner. Human lymphoblastoid cell line (Raji), a poor host for HCV pseudotype infection, exhibited a four- to sixfold enhancement of pseudotype-mediated cell death upon incubation with antibody at nonneutralizing concentrations. A similar enhancement of cell culture-grown HCV infectivity by a human monoclonal antibody was also observed. Taken together, antibodies to viral epitopes enhancing HCV infection need to be taken into consideration for pathogenesis and in the development of an effective vaccine.
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Zeisel MB, Fafi-Kremer S, Fofana I, Barth H, Stoll-Keller F, Doffoel M, Baumert TF. Neutralizing antibodies in hepatitis C virus infection. World J Gastroenterol 2007; 13:4824-30. [PMID: 17828813 PMCID: PMC4611760 DOI: 10.3748/wjg.v13.i36.4824] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays, the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for HCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses. In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of HCV infection and characterization of the impact of neutralizing antibodies for control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for HCV pathogenesis.
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Affiliation(s)
- Mirjam-B Zeisel
- Inserm Unite 748, Universite Louis Pasteur, 3 Rue Koeberle, Strasbourg F-67000, France
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Yu X, Qiao M, Atanasov I, Hu Z, Kato T, Liang TJ, Zhou ZH. Cryo-electron microscopy and three-dimensional reconstructions of hepatitis C virus particles. Virology 2007; 367:126-34. [PMID: 17618667 DOI: 10.1016/j.virol.2007.05.038] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 05/04/2007] [Accepted: 05/09/2007] [Indexed: 10/23/2022]
Abstract
The structural details of hepatitis C virus (HCV) have been elusive because of the lack of a robust tissue culture system for producing an adequate amount of virions from infectious sources for in-depth three-dimensional (3D) structural analysis. Using both negative-stain and cryo-electron microscopy (cryoEM), we show that HCV virions isolated from cell culture have a rather uniform size of 500 A in diameter and that recombinantly expressed HCV-like particles (HCV-LPs) have similar morphologic, biophysical and antigenic features in spite of the varying sizes of the particles. 3D reconstructions were obtained from HCV-LPs with the same size as the HCV virions in the presence and absence of monoclonal antibodies bound to the E1 glycoprotein. The 3D reconstruction of HCV-LP reveals a multilayered architecture, with smooth outer-layer densities arranged in a 'fishbone' configuration. Reconstruction of the particles in complex with anti-E1 antibodies shows that sites of the E1 epitope are exposed and surround the 5-, 3- and 2-fold axes. The binding pattern of the anti-E1 antibody and the fitting of the structure of the dengue virus E glycoprotein into our 3D reconstructions further suggest that the HCV-LP E1 and E2 proteins form a tetramer (or dimer of heterodimers) that corresponds morphologically and functionally to the flavivirus E homodimer. This first 3D structural analysis of HCV particles offers important insights into the elusive mechanisms of HCV assembly and maturation.
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Affiliation(s)
- Xuekui Yu
- Department of Pathology and Laboratory Medicine, The University of Texas Medical School at Houston, Houston, TX 77030, USA
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Molina S, Castet V, Fournier-Wirth C, Pichard-Garcia L, Avner R, Harats D, Roitelman J, Barbaras R, Graber P, Ghersa P, Smolarsky M, Funaro A, Malavasi F, Larrey D, Coste J, Fabre JM, Sa-Cunha A, Maurel P. The low-density lipoprotein receptor plays a role in the infection of primary human hepatocytes by hepatitis C virus. J Hepatol 2007; 46:411-9. [PMID: 17156886 DOI: 10.1016/j.jhep.2006.09.024] [Citation(s) in RCA: 214] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 09/26/2006] [Accepted: 09/29/2006] [Indexed: 12/20/2022]
Abstract
BACKGROUND/AIMS The direct implication of low-density lipoprotein receptor (LDLR) in hepatitis C virus (HCV) infection of human hepatocyte has not been demonstrated. Normal primary human hepatocytes infected by serum HCV were used to document this point. METHODS Expression and activity of LDLR were assessed by RT-PCR and LDL entry, in the absence or presence of squalestatin or 25-hydroxycholesterol that up- or down-regulates LDLR expression, respectively. Infection was performed in the absence or presence of LDL, HDL, recombinant soluble LDLR peptides encompassing full-length (r-shLDLR4-292) or truncated (r-shLDLR4-166) LDL-binding domain, monoclonal antibodies against r-shLDLR4-292, squalestatin or 25-hydroxycholesterol. Intracellular amounts of replicative and genomic HCV RNA strands used as end point of infection were assessed by RT-PCR. RESULTS r-shLDLR4-292, antibodies against r-shLDLR4-292 and LDL inhibited viral RNA accumulation, irrespective of genotype, viral load or liver donor. Inhibition was greatest when r-shLDLR4-292 was present at the time of inoculation and gradually decreased as the delay between inoculation and r-shLDLR4-292 treatment increased. In hepatocytes pre-treated with squalestatin or 25-hydroxycholesterol before infection, viral RNA accumulation increased or decreased in parallel with LDLR mRNA expression and LDL entry. CONCLUSIONS LDLR is involved at an early stage in infection of normal human hepatocytes by serum-derived HCV virions.
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MESH Headings
- Adolescent
- Adult
- Aged
- Antibodies/physiology
- Anticholesteremic Agents/pharmacology
- Bridged Bicyclo Compounds, Heterocyclic/pharmacology
- CD18 Antigens/physiology
- Cells, Cultured
- Female
- Gene Expression Regulation/drug effects
- Hepacivirus/genetics
- Hepacivirus/pathogenicity
- Hepacivirus/physiology
- Hepatitis C/pathology
- Hepatitis C/physiopathology
- Hepatocytes/pathology
- Hepatocytes/virology
- Humans
- Hydroxycholesterols/pharmacology
- Lipoproteins, HDL/physiology
- Lipoproteins, LDL/physiology
- Male
- Middle Aged
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Receptors, LDL/genetics
- Receptors, LDL/immunology
- Receptors, LDL/physiology
- Scavenger Receptors, Class B/physiology
- Tricarboxylic Acids/pharmacology
- Viral Load
- Virion
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Affiliation(s)
- Sonia Molina
- Inserm, U632, Hepatic Physiopathology, 1919 route de Mende, 34293 Montpellier Cedex 5, France
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15
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Basu A, Kanda T, Beyene A, Saito K, Meyer K, Ray R. Sulfated homologues of heparin inhibit hepatitis C virus entry into mammalian cells. J Virol 2007; 81:3933-41. [PMID: 17287282 PMCID: PMC1866147 DOI: 10.1128/jvi.02622-06] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The mechanism of entry of hepatitis C virus (HCV) through interactions between the envelope glycoproteins and specific cell surface receptors remains unclear at this time. We have previously shown with the vesicular stomatitis virus (VSV)/HCV pseudotype model that the hypervariable region 1 of the HCV E2 envelope glycoprotein helps in binding with glycosaminoglycans present on the cell surface. In this study, we have examined the binding of HCV envelope glycoproteins with chemically modified derivatives of heparin. Furthermore, we have determined the functional relevance of the interaction of heparin derivatives with HCV envelope glycoproteins for infectivity by using a human immunodeficiency virus (HIV)/HCV pseudotype, a VSV/HCV pseudotype, and cell culture-grown HCV genotype 1a. Taken together, our results suggest that the HCV envelope glycoproteins rely upon O-sulfated esters of a heparin homologue to facilitate entry into mammalian cells.
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Affiliation(s)
- Arnab Basu
- Division of Infectious Diseases & Immunology, Department of Internal Medicine, Saint Louis University, 3635 Vista Ave., FDT-8N, St. Louis, MO 63110, USA
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16
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Kouvatsis V, Argnani R, Tsitoura E, Arsenakis M, Georgopoulou U, Mavromara P, Manservigi R. Characterization of herpes simplex virus type 1 recombinants that express and incorporate high levels of HCV E2-gC chimeric proteins. Virus Res 2006; 123:40-9. [PMID: 16989918 DOI: 10.1016/j.virusres.2006.07.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 07/21/2006] [Accepted: 07/27/2006] [Indexed: 12/18/2022]
Abstract
We report the construction of two HSV-1 recombinants encoding chimeric forms of the E2 glycoprotein of HCV-1a composed of the ectodomain of E2 (aa384-611 or 384-711) fused to different parts of the transmembrane and cytoplasmic domain of the HSV-1 gC glycoprotein (gC). The parental HSV-1, known as KgBpK(-)gC(-), is deleted for gC and the main heparan sulphate (HS) binding domain of gB, and it exhibits impaired binding (ca. 80%) to HS compared to the wild type virus KOS [Laquerre, S., Argnani, R., Anderson, D.B., Zucchini, S., Manservigi, R., Glorioso, J.C., 1998. Heparan sulphate proteoglycan binding by herpes simplex virus type 1 glycoproteins B and C, which differ in their contributions to virus attachment, penetration, and cell-to-cell spread. J. Virol. 72, 6119-6130]. We show that gC:E2 proteins are efficiently expressed and transported to the cell surface. We also demonstrate that HSV-1 can incorporate both gC:E2 chimeric proteins into particles and show that incorporation of both chimeric molecules in the viral envelope partially restored binding (ca. 20%) of the HSV-1 recombinants to heparan sulphate. Finally, we showed that the gC:E2ScaI chimeric glycoprotein was able to bind a recombinant form of hCD81 and virion-expressed gC:E2ScaI permitted the binding of the HSV-1 recombinant virus to the hCD81 molecule.
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Affiliation(s)
- V Kouvatsis
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Athens 11521, Greece
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Abstract
With an estimated 170 million infected individuals, hepatitis C virus (HCV) has a major impact on public health. A vaccine protecting against HCV infection is not available, and current antiviral therapies are characterized by limited efficacy, high costs, and substantial side effects. Binding of the virus to the cell surface followed by viral entry is the first step in a cascade of interactions between virus and the target cell that is required for the initiation of infection. Because this step represents a critical determinant of tissue tropism and pathogenesis, it is a major target for host cell responses such as antibody-mediated virus-neutralization-and a promising target for new antiviral therapy. The recent development of novel tissue culture model systems for the study of the first steps of HCV infection has allowed rapid progress in the understanding of the molecular mechanisms of HCV binding and entry. This review summarizes the impact of recently identified viral and host cell factors for HCV attachment and entry. Clinical implications of this important process for the pathogenesis of HCV infection and novel therapeutic interventions are discussed.
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Affiliation(s)
- Heidi Barth
- Department of Medicine II, University of Freiburg, Freiburg, Germany
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18
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Kanda T, Basu A, Steele R, Wakita T, Ryerse JS, Ray R, Ray RB. Generation of infectious hepatitis C virus in immortalized human hepatocytes. J Virol 2006; 80:4633-9. [PMID: 16611923 PMCID: PMC1472020 DOI: 10.1128/jvi.80.9.4633-4639.2006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Progress in understanding hepatitis C virus (HCV) biology has remained a challenge due to the lack of an efficient cell culture system for virus growth. In this study, we examined HCV core protein-mediated immortalized human hepatocytes (IHH) for growth of HCV. In vitro-transcribed full-length RNA from HCV genotype 1a (clone H77) was introduced into IHH by electroporation. Reverse transcription-PCR of cellular RNA isolated from HCV genome-transfected IHH suggested that viral RNA replication occurred. IHH transfected with the full-length HCV genome also displayed viral protein expression by indirect immunofluorescence. In contrast, cells transfected with polymerase-defective HCV (H77/GND) RNA as a negative control did not exhibit expression of the viral genome. Immunogold labeling demonstrated localization of E1 protein in the rough endoplasmic reticulum of RNA-transfected IHH. Virus-like particles of approximately 50 nm were observed in the cytoplasm. After being inoculated with culture media of cells transfected with the full-length HCV genome, naïve IHH displayed NS5a protein expression in a dilution-dependent manner, but expression of NS5a was inhibited by prior incubation of culture medium with HCV-infected patient sera. NS5a-positive immunofluorescence of cell culture media of IHH transfected with full-length H77 RNA yielded approximately 4.5 x 10(4) to 1 x 10(5) focus-forming units/ml. A similar level of virus growth was observed upon transfection of RNA from HCV genotype 2a (JFH1) into IHH. Taken together, our results suggest that IHH support HCV genome replication and virus assembly.
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Affiliation(s)
- Tatsuo Kanda
- Department of Pathology, Saint Louis University, 3635 Vista Avenue, St. Louis, Missouri 63110, USA
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19
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Abstract
Progress in understanding hepatitis C virus (HCV) biology has remained a challenge due to the lack of an efficient cell culture system for virus growth. In this study, we examined HCV core protein-mediated immortalized human hepatocytes (IHH) for growth of HCV. In vitro-transcribed full-length RNA from HCV genotype 1a (clone H77) was introduced into IHH by electroporation. Reverse transcription-PCR of cellular RNA isolated from HCV genome-transfected IHH suggested that viral RNA replication occurred. IHH transfected with the full-length HCV genome also displayed viral protein expression by indirect immunofluorescence. In contrast, cells transfected with polymerase-defective HCV (H77/GND) RNA as a negative control did not exhibit expression of the viral genome. Immunogold labeling demonstrated localization of E1 protein in the rough endoplasmic reticulum of RNA-transfected IHH. Virus-like particles of approximately 50 nm were observed in the cytoplasm. After being inoculated with culture media of cells transfected with the full-length HCV genome, naïve IHH displayed NS5a protein expression in a dilution-dependent manner, but expression of NS5a was inhibited by prior incubation of culture medium with HCV-infected patient sera. NS5a-positive immunofluorescence of cell culture media of IHH transfected with full-length H77 RNA yielded approximately 4.5 x 10(4) to 1 x 10(5) focus-forming units/ml. A similar level of virus growth was observed upon transfection of RNA from HCV genotype 2a (JFH1) into IHH. Taken together, our results suggest that IHH support HCV genome replication and virus assembly.
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Bartosch B, Cosset FL. Cell entry of hepatitis C virus. Virology 2006; 348:1-12. [PMID: 16455127 DOI: 10.1016/j.virol.2005.12.027] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 11/30/2005] [Accepted: 12/15/2005] [Indexed: 12/30/2022]
Abstract
Hepatitis C virus (HCV), an important human pathogen, is an enveloped, positive-stranded RNA virus classified in the hepacivirus genus of the Flaviviridae family. Cell attachment of flaviviruses generally leads to endocytosis of bound virions. Systems that support HCV replication and particle formation in vitro are emerging only now, 16 years after the discovery of the virus. Albeit this limitation, the route of HCV cell entry as well as 'capture' molecules involved in low-affinity interactions for the initial contact of HCV with target cells and potential high-affinity receptor candidates that may mediate HCV trafficking and fusion has been described. The objective of this review is to summarize the contribution of different HCV model systems to our current knowledge about structure of the HCV GPs E1 and E2 and their roles in cell entry comprising cell attachment, interactions with cellular receptors, endocytosis, and fusion.
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