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Second malignant neoplasms in lymphomas, secondary lymphomas and lymphomas in metabolic disorders/diseases. Cell Biosci 2022; 12:30. [PMID: 35279210 PMCID: PMC8917635 DOI: 10.1186/s13578-022-00763-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 02/14/2022] [Indexed: 12/02/2022] Open
Abstract
With inconsistent findings, evidence has been obtained in recent years that metabolic disorders are closely associated with the development of lymphomas. Studies and multiple analyses have been published also indicating that some solid tumor survivors develop a secondary lymphoma, whereas some lymphoma survivors subsequently develop a second malignant neoplasm (SMN), particularly solid tumors. An interaction between the multiple etiologic factors such as genetic factors and late effects of cancer therapy may play an important role contributing to the carcinogenesis in patients with metabolic diseases or with a primary cancer. In this review, we summarize the current knowledge of the multiple etiologic factors for lymphomagenesis, focusing on the SMN in lymphoma, secondary lymphomas in primary cancers, and the lymphomas associated to metabolic disorders/diseases, which have been received less attention previously. Further, we also review the data of coexistence of lymphomas and hepatocellular carcinoma (HCC) in patients with infection of hepatitis C virus and hepatitis B virus.
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2
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Couronné L, Bachy E, Roulland S, Nadel B, Davi F, Armand M, Canioni D, Michot JM, Visco C, Arcaini L, Besson C, Hermine O. From hepatitis C virus infection to B-cell lymphoma. Ann Oncol 2019; 29:92-100. [PMID: 29045541 DOI: 10.1093/annonc/mdx635] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In addition to liver disorders, hepatitis C virus (HCV) is also associated with extrahepatic immune manifestations and B-cell non-Hodgkin lymphoma (NHL), especially marginal zone lymphoma, de novo or transformed diffuse large B-cell lymphoma and to a lesser extent, follicular lymphoma. Epidemiological data and clinical observations argue for an association between HCV and lymphoproliferative disorders. The causative role of HCV in NHL has been further supported by the response to antiviral therapy. Pathophysiological processes at stake leading from HCV infection to overt lymphoma still need to be further elucidated. Based on reported biological studies, several mechanisms of transformation seem however to emerge. A strong body of evidence supports the hypothesis of an indirect transformation mechanism by which sustained antigenic stimulation leads from oligoclonal to monoclonal expansion and sometimes to frank lymphoma, mostly of marginal zone subtype. By infecting lymphocytes, HCV could play a direct role in cellular transformation, particularly in de novo large B-cell lymphoma. Finally, HCV is associated with follicular lymphoma in a subset of patients. In this setting, it may be hypothesized that inflammatory cytokines stimulate proliferation and transformation of IgH-BCL2 clones that are increased during chronic HCV infection. Unraveling the pathogenesis of HCV-related B-cell lymphoproliferation is of prime importance to optimize therapeutic strategies, especially with the recent development of new direct-acting antiviral drugs.
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Affiliation(s)
- L Couronné
- Department of Hematology, Assistance Publique-Hôpitaux de Paris (APHP), Necker Hospital, Paris, France.,INSERM UMR 1163, CNRS ERL 8254, Imagine Institute, Paris, France.,Paris Descartes-Sorbonne Paris Cité University, Paris, France
| | - E Bachy
- Cancer Research Center of Lyon, INSERM U1052, CNRS UMR 5286, Lyon, France.,Department of Hematology, Lyon Sud Hospital, Lyon, France
| | - S Roulland
- Center of Immunology of Marseille-Luminy, Aix Marseille University, Marseille, France
| | - B Nadel
- Center of Immunology of Marseille-Luminy, Aix Marseille University, Marseille, France
| | - F Davi
- INSERM U1104, Marseille, France.,CNRS UMR 7280, Marseille, France.,Department of Hematology, Pitié-Salpêtrière Hospital, Pierre et Marie Curie University, Paris, France
| | - M Armand
- INSERM U1104, Marseille, France.,CNRS UMR 7280, Marseille, France.,Department of Hematology, Pitié-Salpêtrière Hospital, Pierre et Marie Curie University, Paris, France
| | - D Canioni
- Department of Pathology, Necker Hospital, AP-HP, Paris Descartes-Sorbonne Paris Cité University, Paris, France
| | - J M Michot
- Department of Hematology and Drug Development, Gustave Roussy Institute, Villejuif; France
| | - C Visco
- Department of Cell Therapy and Hematology, San Bortolo Hospital, Vicenza, Italy
| | - L Arcaini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Departement of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - C Besson
- Department of Hematology and Oncology, Hospital of Versailles, Le Chesnay, France.,University of Versailles Saint Quentin en Yvelines, Paris-Saclay University, Communauté Paris-Saclay, Paris, France.,INSERM U1184, Center for Immunology of Viral Infections and Autoimmune Diseases, Le Kremlin-Bicêtre, France
| | - O Hermine
- Department of Hematology, Assistance Publique-Hôpitaux de Paris (APHP), Necker Hospital, Paris, France.,INSERM UMR 1163, CNRS ERL 8254, Imagine Institute, Paris, France.,Paris Descartes-Sorbonne Paris Cité University, Paris, France
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3
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Kumar A, Rajput MK, Paliwal D, Yadav A, Chhabra R, Singh S. Genotyping & diagnostic methods for hepatitis C virus: A need of low-resource countries. Indian J Med Res 2018; 147:445-455. [PMID: 30082568 PMCID: PMC6094507 DOI: 10.4103/ijmr.ijmr_1850_16] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) infection is a blood borne and transfusion-transmitted infection (TTI). It has emerged as one of the major health challenges worldwide. In India, around 12-18 million peoples are infected with HCV, but in terms of prevalence percentage, its looks moderate due to large population. The burden of the HCV infection increases due to lack of foolproof screening of blood and blood products before transfusion. The qualified screening and quantification of HCV play an important role in diagnosis and treatment of HCV-related diseases. If identified early, HCV infection can be managed and treated by recently available antiviral therapies with fewer side effects. However, its identification at chronic phase makes its treatment very challenging and sometimes ineffective. The drugs therapy for HCV infection treatment is also dependent on its genotype. Different genotypes of HCV differ from each other at genomic level. The RNA viruses (such as HCV) are evolving perpetually due to interaction and integration among people from different regions and countries which lead to varying therapeutic response in HCV-infected patients in different geographical regions. Therefore, proper diagnosis for infecting virus and then exact determination of genotype become important for targeted treatment. This review summarizes the general information on HCV, and methods used for its diagnosis and genotyping.
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Affiliation(s)
- Anoop Kumar
- National Institute of Biologicals, Noida, India
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4
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Bunchorntavakul C, Mitrani R, Reddy KR. Advances in HCV and Cryoglobulinemic Vasculitis in the Era of DAAs: Are We at the End of the Road? J Clin Exp Hepatol 2018; 8:81-94. [PMID: 29743799 PMCID: PMC5938331 DOI: 10.1016/j.jceh.2017.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 11/30/2017] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C Virus (HCV)-related Mixed Cryoglobulinemia (MC) is a unique condition with complex pathogenesis that involves HCV antigen-driven B-lymphocyte clonal proliferation and mutagenesis. Clinical spectrum of MC ranges from asymptomatic state to clinically-apparent vasculitis involving multiple organs. In the era of Direct-Acting Antiviral (DAA) therapy, patients with HCV-related MC achieve high rates of viral clearance that is commonly accompanied by an improvement in clinical symptoms as well as immunological profiles. Rituximab, either alone or in combination with DAA, has also been shown to be effective. Nevertheless, there have been limited and somewhat conflicting data, particularly over the long-term, regarding the rate and degree of clinical response of MC following DAA therapy. It appears that we have come quite a long way in the last decade with this condition. As with non-MC related HCV, undoubtedly long term outcome data will be forthcoming over the next few years. As we move forward successful therapy of HCV is not likely to be a challenge in contrast to access to therapy.
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Affiliation(s)
- Chalermrat Bunchorntavakul
- Division of Gastroenterology and Hepatology, Department of Medicine, Rajavithi Hospital, College of Medicine, Rangsit University, Rajavithi Road, Ratchathewi, Bangkok 10400, Thailand
| | - Robert Mitrani
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Pennsylvania, 2 Dulles, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - K. Rajender Reddy
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Pennsylvania, 2 Dulles, 3400 Spruce Street, Philadelphia, PA 19104, USA
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5
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Alves NS, Mendes YS, Souza TLF, Bianconi ML, Silva JL, Gomes AMO, Oliveira AC. A biophysical characterization of the interaction of a hepatitis C virus membranotropic peptide with micelles. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:359-71. [PMID: 26773352 DOI: 10.1016/j.bbapap.2016.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 01/02/2016] [Accepted: 01/05/2016] [Indexed: 10/22/2022]
Abstract
Membrane fusion is a highly regulated process that allows enveloped viruses to enter cells and replicate. Viral glycoproteins trigger membrane fusion by means of internal sequences known as fusion peptides. The hepatitis C virus (HCV) genome encodes the envelope glycoproteins E1 and E2, but their specific roles in the fusion step and the localization of the fusion peptide remain uncharacterized. Here, we studied the biophysics of the interactions between the glycoprotein E2 peptide HCV421-445 and four different micellar systems providing ionic, non-ionic and zwitterionic surfaces to investigate the importance of electrostatic interactions for peptide-membrane binding. Circular dichroism, fluorescence spectroscopy and calorimetry were used to characterize peptide-micelle interactions and structural changes. Fluorescence quenching showed that HCV421-445 interacts with SDS or CTAB ionic, n-OGP non-ionic and DPC zwitterionic micelles. The indole ring of Trp seems to anchor the peptide in micelles. Trp residues seem to be more deeply inserted in ionic and non-ionic micelles where peptide interactions are more stable than with DPC zwitterionic micelles. The interaction with zwitterionic micelles appears to occur at the surface. Both interaction types are exothermic because of peptide-micelle interactions and a gain of secondary structure in the helical conformation. HCV421-445 interacts with detergent monomers and micelles. Peptide-micelle interaction is pH-independent. HCV421-445 interacts with membranes, promoting aggregation and coalescence of vesicles with content leakage, suggesting that HCV421-445 may participate in membrane fusion. This structural characterization contributes to our understanding of the molecular process that promotes fusion, which is important in the further development of new antiviral therapies.
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Affiliation(s)
- N S Alves
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - Y S Mendes
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - T L F Souza
- Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - M L Bianconi
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - J L Silva
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - A M O Gomes
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
| | - A C Oliveira
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
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6
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Abstract
Chronic infection with the hepatitis C virus (HCV) is a major cause of liver disease worldwide and is also responsible for extrahepatic manifestations (EHMs) involving the skin, kidneys, salivary glands, eyes, thyroid, and immune system. Mixed cryoglobulinemia is the prototype EHM related to HCV infection. Although these HCV-related EHMs may contribute to significant rates of morbidity affecting patient's quality of life and survival, most of these complications can reverse after HCV eradication by interferon therapy. This notwithstanding, individual patients may have an irreversible injury in various organs that is not reversed by a cure of the HCV infection.
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Affiliation(s)
- Mauro Viganò
- Hepatology Division, Ospedale San Giuseppe, Università degli Studi di Milano, Via San Vittore 12, Milan 20122, Italy
| | - Massimo Colombo
- Division of Gastroenterology and Hepatology, "A. M. and A. Migliavacca" Center for Liver Disease, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Via F. Sforza 35, Milan 20122, Italy.
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7
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Sulyok M, Makara M, Újhelyi E, Vályi-Nagy I. Non-Hodgkin lymphoma and hepatitis C: where we are and what next? Pathol Oncol Res 2014; 21:1-7. [PMID: 25273531 DOI: 10.1007/s12253-014-9845-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/19/2014] [Indexed: 12/16/2022]
Abstract
The association between hepatitis C virus and certain B-cell non-Hodgkin lymphomas, such as marginal zone lymphomas, is supported by epidemiological studies. The exact pathogenetic mechanism is still unknown but both chronic antigenic stimulation and viral lymphotropism may contribute to the evolution of the malignant clone. Furthermore, the hematologic response following hepatitis C antiviral treatment suggests that the virus may have an etiologic role. Interferon and ribavirin based treatment proved to be successful in small case series of hepatitis C virus associated splenic lymphoma with villous lymphocytes, therefore, it is suggested that antiviral treatment could be an alternative to chemo-immunotherapy. In the near future new more potent direct acting antivirals will make interferon free treatments possible. It is still an open question whether these new short-course regimens are also effective in the treatment of associated lymphomas and what is the importance of the lymphoid reservoir in eliminating HCV.
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Affiliation(s)
- Mihály Sulyok
- St. István and St László Hospital, Hepatology Center, 1097, Albert Flórián str. 5-7, Budapest, Hungary,
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8
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Unexpected structural features of the hepatitis C virus envelope protein 2 ectodomain. J Virol 2014; 88:10280-8. [PMID: 24991010 DOI: 10.1128/jvi.00874-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hepatitis C virus (HCV), a member of the family Flaviviridae, is a leading cause of chronic liver disease and cancer. Recent advances in HCV therapeutics have resulted in improved cure rates, but an HCV vaccine is not available and is urgently needed to control the global pandemic. Vaccine development has been hampered by the lack of high-resolution structural information for the two HCV envelope glycoproteins, E1 and E2. Recently, Kong and coworkers (Science 342:1090-1094, 2013, doi:10.1126/science.1243876) and Khan and coworkers (Nature 509[7500]:381-384, 2014, doi:10.1038/nature13117) independently determined the structure of the HCV E2 ectodomain core with some unexpected and informative results. The HCV E2 ectodomain core features a globular architecture with antiparallel β-sheets forming a central β sandwich. The residues comprising the epitopes of several neutralizing and nonneutralizing human monoclonal antibodies were also determined, which is an essential step toward obtaining a fine map of the human humoral response to HCV. Also clarified were the regions of E2 that directly bind CD81, an important HCV cellular receptor. While it has been widely assumed that HCV E2 is a class II viral fusion protein (VFP), the newly determined structure suggests that the HCV E2 ectodomain shares structural and functional similarities only with domain III of class II VFPs. The new structural determinations suggest that the HCV glycoproteins use a different mechanism than that used by class II fusion proteins for cell fusion.
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9
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Lü X, Yao M, Zhang JM, Yang J, Lei YF, Huang XJ, Jia ZS, Ma L, Lan HY, Xu ZK, Yin W. Identification of peptides that bind hepatitis C virus envelope protein E2 and inhibit viral cellular entry from a phage-display peptide library. Int J Mol Med 2014; 33:1312-8. [PMID: 24573486 DOI: 10.3892/ijmm.2014.1670] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/10/2014] [Indexed: 11/06/2022] Open
Abstract
Hepatitis C virus (HCV) envelope protein E2 is required for the entry of HCV into cells. Viral envelope proteins interact with cell receptors in a multistep process, which may be a promising target for the development of novel antiviral agents. In this study, a heptapeptide M13 phage-display library was screened for peptides that bind specifically to prokaryotically expressed, purified truncated HCV envelope protein E2. ELISA assay was used to quantify the binding of the peptides to HCV E2 protein. Flow cytometry, quantitative reverse-transcription PCR and western blotting were used to investigate the inhibition effect of one peptide on HCV infection in hepatoma cells (Huh7.5) in vitro. Four peptides capable of binding specifically to HCV E2 protein were obtained after three rounds of biopanning. Peptide C18 (WPWHNHR), with the highest affinity for binding HCV E2 protein, was synthesized. The results showed that peptide C18 inhibited the viral infectivity of both HCV pseudotype particles (HCVpp) harboring HCV envelope glycoproteins and cell-culture produced HCV (HCVcc). Thus, this study demonstrated that peptide C18 is a potential candidate for anti-HCV therapy as a novel viral entry inhibitor.
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Affiliation(s)
- Xin Lü
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Min Yao
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Jian-Min Zhang
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Jing Yang
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Ying-Feng Lei
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Xiao-Jun Huang
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Zhan-Sheng Jia
- Center of Diagnosis and Treatment for Infectious Disease of Chinese PLA, Tangdu Hospital, the Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Li Ma
- Center of Diagnosis and Treatment for Infectious Disease of Chinese PLA, Tangdu Hospital, the Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Hai-Yun Lan
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Zhi-Kai Xu
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Wen Yin
- Department of Microbiology, the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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Samuel DG, Rees IW. Extrahepatic manifestations of hepatitis C virus (HCV). Frontline Gastroenterol 2013; 4:249-254. [PMID: 28839734 PMCID: PMC5369834 DOI: 10.1136/flgastro-2013-100315] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 04/21/2013] [Accepted: 04/25/2013] [Indexed: 02/04/2023] Open
Abstract
Hepatitis C virus (HCV) is an infectious disease that often remains asymptotic and unrecognised until complications of the virus arise. These often include extrahepatic manifestations of the virus, which first bring patients into contact with the medical profession. First recognised in the 1990s several syndromes and conditions have now been linked to hepatitis C, while others are still emerging. In some patients, extrahepatic manifestations can be the dominant feature, while hepatic disease is mild. Some conditions have an established association with the virus with a proven pathophysiological and epidemiology, such as cryoglobulinaemia. Others have consistently been found to be seen in patients with HCV, but the underlying cause of these conditions is not clearly understood. These include porphyria cutanea tarda. Many other autoimmune conditions are commonly seen in the patients with HCV as well as nephropathies, but the exact interplay between virus and resulting clinical condition is not clear. Clinicians have to have a high index of suspicion and a knowledge of the extrahepatic manifestations of HCV in order to not only treat the manifestation but also in initiated timely therapies for the underlying HCV.
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Affiliation(s)
- David G Samuel
- Department of Gastroenterology, Prince Phillip Hospital, Llanelli, UK
| | - Ian W Rees
- Department of Gastroenterology, Prince Phillip Hospital, Llanelli, UK
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11
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Idrees S, Ashfaq UA, Khaliq S. HCV Envelope protein 2 sequence comparison of Pakistani isolate and In-silico prediction of conserved epitopes for vaccine development. J Transl Med 2013; 11:105. [PMID: 23631455 PMCID: PMC3663723 DOI: 10.1186/1479-5876-11-105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/23/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND HCV is causing hundreds of cases yearly in Pakistan and has become a threat for Pakistani population. HCV E2 protein is a transmembrane protein involved in viral attachment and thus can serve as an important target for vaccine development but because of its variability, vaccine development against it has become a challenge. Therefore, this study was designed to isolate the HCV E2 gene from Pakistani HCV infected patients of 3a genotype, to perform In-silico analysis of HCV E2 isolated in Pakistan and to analyze HCV E2 protein sequence in comparison with other E2 proteins belonging to 3a and 1a genotypes to find potential conserved B-cells and T-cell epitopes that can be important in designing novel inhibitory compounds and peptide vaccine against genotype 3a and 1a. PATIENTS AND METHODS Patients were selected on the basis of elevated serum ALT and AST levels at least for six months, histological examination, and detection of serum HCV RNA anti-HCV antibodies (3rd generation ELISA). RNA isolation, cDNA synthesis, amplification, cloning and sequencing was performed from 4 patient's serum samples in order to get the HCV E2 sequence. HCV E2 protein of Pakistani origin was analyzed using various bioinformatics tools including sequence and structure tools. RESULTS HCV E1 protein modeling was performed with I-TASSER online server and quality of the model was assessed with ramchandran plot and Z-score. A total of 3 B-cell and 3 T-cell epitopes were found to be highly conserved among HCV 3a and 1a genotype. CONCLUSION The present study revealed potential conserved B-cell and T-cell epitopes of the HCV E2 protein along with 3D protein modeling. These conserved B-cell and T-cell epitopes can be helpful in developing effective vaccines against HCV and thus limiting threats of HCV infection in Pakistan.
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Affiliation(s)
- Sobia Idrees
- Human Molecular Biology Group, Department of Bioinformatics and Biotechnology, Government College University (GCU), Faisalabad, Pakistan
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12
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Radom F, Jurek PM, Mazurek MP, Otlewski J, Jeleń F. Aptamers: molecules of great potential. Biotechnol Adv 2013; 31:1260-74. [PMID: 23632375 DOI: 10.1016/j.biotechadv.2013.04.007] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 03/27/2013] [Accepted: 04/19/2013] [Indexed: 01/08/2023]
Abstract
Aptamers emerged over 20 years ago as a class of nucleic acids able to recognize specific targets. Today, aptamer-related studies constitute a large and important field of biotechnology. Functional oligonucleotides have proved to be a versatile tool in biomedical research due to the ease of synthesis, a wide range of potentially recognized molecular targets and the simplicity of selection. Similarly to antibodies, aptamers can be used to detect or isolate specific molecules, as well as to act as targeting and therapeutic agents. In this review we present different approaches to aptamer application in nanobiotechnology, diagnostics and medicine.
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Affiliation(s)
- Filip Radom
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Tamka 2, 50-137 Wroclaw, Poland
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13
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Kim CW, Chang KM. Hepatitis C virus: virology and life cycle. Clin Mol Hepatol 2013; 19:17-25. [PMID: 23593605 PMCID: PMC3622851 DOI: 10.3350/cmh.2013.19.1.17] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 03/15/2012] [Accepted: 03/18/2012] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) is a positive sense, single-stranded RNA virus in the Flaviviridae family. It causes acute hepatitis with a high propensity for chronic infection. Chronic HCV infection can progress to severe liver disease including cirrhosis and hepatocellular carcinoma. In the last decade, our basic understanding of HCV virology and life cycle has advanced greatly with the development of HCV cell culture and replication systems. Our ability to treat HCV infection has also been improved with the combined use of interferon, ribavirin and small molecule inhibitors of the virally encoded NS3/4A protease, although better therapeutic options are needed with greater antiviral efficacy and less toxicity. In this article, we review various aspects of HCV life cycle including viral attachment, entry, fusion, viral RNA translation, posttranslational processing, HCV replication, viral assembly and release. Each of these steps provides potential targets for novel antiviral therapeutics to cure HCV infection and prevent the adverse consequences of progressive liver disease.
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Affiliation(s)
- Chang Wook Kim
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Kyong-Mi Chang
- GI/Hepatology Research Center, Philadelphia VA Medical Center, Philadelphia, PA, USA
- Department of Internal Medicine, University of Pennsylvania, Philadelphia, PA, USA
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14
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Morphologic features of extrahepatic manifestations of hepatitis C virus infection. Clin Dev Immunol 2012; 2012:740138. [PMID: 22919404 PMCID: PMC3420144 DOI: 10.1155/2012/740138] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 06/28/2012] [Indexed: 12/18/2022]
Abstract
Cirrhosis and hepatocellular carcinoma are the prototypic complications of chronic hepatitis C virus infection in the liver. However, hepatitis C virus also affects a variety of other organs that may lead to significant morbidity and mortality. Extrahepatic manifestations of hepatitis C infection include a multitude of disease processes affecting the small vessels, skin, kidneys, salivary gland, eyes, thyroid, and immunologic system. The majority of these conditions are thought to be immune mediated. The most documented of these entities is mixed cryoglobulinemia. Morphologically, immune complex depositions can be identified in small vessels and glomerular capillary walls, leading to leukoclastic vasculitis in the skin and membranoproliferative glomerulonephritis in the kidney. Other HCV-associated entities include porphyria cutanea tarda, lichen planus, necrolytic acral erythema, membranous glomerulonephritis, diabetic nephropathy, B-cell non-Hodgkin lymphomas, insulin resistance, sialadenitis, sicca syndrome, and autoimmune thyroiditis. This paper highlights the histomorphologic features of these processes, which are typically characterized by chronic inflammation, immune complex deposition, and immunoproliferative disease in the affected organ.
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Abstract
The goal of antiviral therapy for patients with chronic hepatitis C virus (HCV) infection is to attain a sustained virologic response (SVR), which is defined as undetectable serum HCV-RNA levels at 6 months after the cessation of treatment. Major improvements in antiviral therapy for chronic hepatitis C have occurred in the past decade. The addition of ribavirin to interferon-alfa therapy and the introduction of pegylated interferon (PEG-IFN) have substantially improved SVR rates in patients with chronic hepatitis C. The optimization of HCV therapy with PEG-IFN and ribavirin continues to evolve. Studies are ongoing that use viral kinetics to tailor therapy to an individual's antiviral response and determine the ideal length of treatment to maximize the chance of SVR. Improved SVR can be achieved with new specific inhibitors that target the HCV NS3/4A protease and the NS5B polymerase. Several long-term follow-up studies have shown that SVR, when achieved, is associated with a very low risk of virologic relapse. Furthermore, antiviral therapy can reduce the morbidity and mortality rates associated with chronic hepatitis C by reducing fibrosis progression, the incidence of cirrhosis, and hepatocellular carcinoma.
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Affiliation(s)
- Jae Young Jang
- Institute for Digestive Research, Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University College of Medicine, Seoul, Korea
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Ashfaq UA, Javed T, Rehman S, Nawaz Z, Riazuddin S. Lysosomotropic agents as HCV entry inhibitors. Virol J 2011; 8:163. [PMID: 21481279 PMCID: PMC3090357 DOI: 10.1186/1743-422x-8-163] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 04/12/2011] [Indexed: 01/26/2023] Open
Abstract
HCV has two envelop proteins named as E1 and E2 which play an important role in cell entry through two main pathways: direct fusion at the plasma membrane and receptor-mediated endocytosis. Fusion of the HCV envelope proteins is triggered by low pH within the endosome. Lysosomotropic agents (LA) such as Chloroquine and Ammonium chloride (NH4Cl) are the weak bases and penetrate in lysosome as protonated form and increase the intracellular pH. To investigate the antiviral effect of LA (Chloroquine and NH4Cl) on pH dependent endocytosis, HCV pseudoparticles (HCVpp) of 1a and 3a genotype were produced and used to infect liver cells. The toxicological effects of Chloroquine and NH4Cl were tested in liver cells through MTT cell proliferation assay. For antiviral screening of Chloroquine and NH4Cl, liver cells were infected with HCVpp of 3a and 1a genotype in the presence or absence of different concentrations of Chloroquine and NH4Cl and there luciferase activity was determined by using a luminometer. The results demonstrated that Chloroquine and NH4Cl showed more than 50% reduction of virus infectivity at 50 μM and 10 mM concentrations respectively. These results suggest that inhibition of HCV at fusion step by increasing the lysosomal pH will be better option to treat chronic HCV.
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Affiliation(s)
- Usman A Ashfaq
- Division of Molecular Medicine, National Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan.
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Chen F, Zhao Y, Liu M, Li D, Wu H, Chen H, Zhu Y, Luo F, Zhong J, Zhou Y, Qi Z, Zhang XL. Functional selection of hepatitis C virus envelope E2-binding Peptide ligands by using ribosome display. Antimicrob Agents Chemother 2010; 54:3355-64. [PMID: 20479194 PMCID: PMC2916351 DOI: 10.1128/aac.01357-09] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 12/07/2009] [Accepted: 04/29/2010] [Indexed: 02/07/2023] Open
Abstract
Small peptides that inhibit the hepatitis C virus (HCV) at the stage of viral entry have the potential to serve as attractive antiviral drugs. Ribosome display is a cell-free system for in vitro selection of peptides from large random peptide libraries. Thus, we utilized a ribosome display library technique for affinity selection of HCV envelope protein E2-binding peptide ligands. Through 13 rounds of selection, the ribosome display system generated high-affinity 12-mer peptides, and the selected peptide PE2D (MARHRNWPLVMV) demonstrated the highest specificity and affinity to the HCV E2 protein. Furthermore, amino acids 489 to 508 (YPPRPCGIVPAKSVCGPVYC) of E2 were identified as crucial for binding to PE2D. The selected peptides, especially PE2D, not only dramatically blocked E2 protein binding to hepatocytes but also dramatically inhibited HCV cell culture (HCVcc) entry into hepatocytes. HCVcc and HCV particles from HCV patient serum samples could also be specifically captured using PE2D. Our study demonstrates that the newly selected peptide ligand PE2D holds great promise for developing a new molecular probe, a therapeutic drug specifically for HCV, or an early-diagnostic reagent for HCV surface envelope antigen E2.
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Affiliation(s)
- Fang Chen
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Yinglan Zhao
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Min Liu
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Dongqing Li
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Hongyan Wu
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Haidan Chen
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Yongzhe Zhu
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Fengling Luo
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Jin Zhong
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Yidan Zhou
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Zhongtian Qi
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
| | - Xiao-Lian Zhang
- State Key Laboratory of Virology and Department of Immunology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China, Department of Microbiology, Second Military Medical University, Shanghai 200433, People's Republic of China, The Unit of Viral Hepatitis, Institut Pasteur of Shanghai, Shanghai 200025, People's Republic of China, Jianghan University, College of Life Science, Department of Biotechnology, Wuhan 430056, People's Republic of China
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Hepatitis C virus infection and lymphoma. Mediterr J Hematol Infect Dis 2010; 3:e2011004. [PMID: 21415946 PMCID: PMC3033108 DOI: 10.4084/mjhid.2010.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 12/15/2010] [Indexed: 12/21/2022] Open
Abstract
Apart from its well known role as an etiological agent for non-A and non-B viral hepatitis, there is growing evidence that hepatitis C virus is associated to B-cell non-Hodgkin lymphoma. The association between HCV and lymphoproliferative disorders has been recently postulated based on epidemiological data, biological studies and clinical observations. Although various subtypes of lymphomas appear to be associated to HCV, diffuse large B-cell lymphoma, small lymphocytic lymphoma/chronic lymphocytic leukemia and marginal zone lymphoma appeared to be particularly represented among HCV-positive patients. The causative role of HCV in those disorders has been further supported by the response to antiviral therapy. Despite a better understanding of pathophysiological processes at stake leading from HCV infection to overt lymphoma, many issues still need to be further elucidated. Although HCV has been demonstrated to directly infect peripheral blood mononuclear cells both in vitro and, in some cases, in vivo, a strong body of evidence rather supports the hypothesis of an indirect transformation mechanism by which sustained antigenic stimulation leads from oligoclonal to monoclonal expansion and sometimes to lymphoma, probably through secondary oncogenic events. Here, we review epidemiological and biological studies, as well as clinical data on antiviral therapy, linking HCV-infection to B-cell non-Hodgkin lymphoma.
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CS-SELEX generates high-affinity ssDNA aptamers as molecular probes for hepatitis C virus envelope glycoprotein E2. PLoS One 2009; 4:e8142. [PMID: 19997645 PMCID: PMC2780912 DOI: 10.1371/journal.pone.0008142] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2009] [Accepted: 10/29/2009] [Indexed: 01/03/2023] Open
Abstract
Currently, the development of effective diagnostic reagents as well as treatments against Hepatitis C virus (HCV) remains a high priority. In this study, we have described the development of an alive cell surface -Systematic Evolution of Ligands by Exponential Enrichment (CS-SELEX) technique and screened the functional ssDNA aptamers that specifically bound to HCV envelope surface glycoprotein E2. Through 13 rounds of selection, the CS-SELEX generated high-affinity ssDNA aptamers, and the selected ssDNA aptamer ZE2 demonstrated the highest specificity and affinity to E2-positive cells. HCV particles could be specifically captured and diagnosed using the aptamer ZE2. A good correlation was observed in HCV patients between HCV E2 antigen-aptamer assay and assays for HCV RNA quantities or HCV antibody detection. Moreover, the selected aptamers, especially ZE2, could competitively inhibit E2 protein binding to CD81, an important HCV receptor, and significantly block HCV cell culture (HCVcc) infection of human hepatocytes (Huh7.5.1) in vitro. Our data demonstrate that the newly selected ssDNA aptamers, especially aptamer ZE2, hold great promise for developing new molecular probes, as an early diagnostic reagent for HCV surface antigen, or a therapeutic drug specifically for HCV.
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Tian ZF, Shen H, Fu XH, Chen YC, Blum HE, Baumert TF, Zhao XP. Interaction of hepatitis C virus envelope glycoprotein E2 with the large extracellular loop of tupaia CD81. World J Gastroenterol 2009; 15:240-4. [PMID: 19132776 PMCID: PMC2653318 DOI: 10.3748/wjg.15.240] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To further analyze the interaction of tupaia CD81 with hepatitis C virus (HCV) envelope protein E2.
METHODS: A tupaia CD81 large extracellular loop (CD81 LEL), which binds to HCV E2 protein, was cloned and expressed as a GST-fusion protein, and interaction of HCV E2 protein with a tupaia CD81 LEL was evaluated by enzyme-linked immunosorbent assay (EIA).
RESULTS: Although tupaia and human CD81 LEL differed in 6 amino acid changes, tupaia CD81 LEL was strongly recognized by anti-CD81 antibodies against human CD81 LEL conformation-dependent epitopes. Investigating LEL CD81-E2 interactions by EIA, we demonstrated that binding of tupaia CD81 LEL GST fusion protein to recombinant HCV E2 protein was markedly reduced compared to binding of human CD81 LEL GST fusion protein to recombinant HCV E2 protein.
CONCLUSION: These data suggest that the structural differences in-between the tupaia and human CD81 may alter the interaction of the large extracellular loop with HCV envelope glycoprotein E2. These findings may be important for the understanding of the mechanisms of binding and entry of HCV to PTHs.
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Abstract
Chronic hepatitis B and C affect approximately 500 million people in the world, with substantial disease burden including liver cirrhosis and hepatocellular carcinoma. For chronic hepatitis B, two treatment strategies are currently available, both with suboptimal response and significant side effects. Promising new drugs are approaching the stage of approval; however, these agents still need further development to control this disease. Based on the understanding of the hepatitis C virus life cycle, new treatment developments for chronic hepatitis C tend to succeed rapidly; therefore, it is only a matter of time before new therapies emerge. This review summarizes the most important new agents available for treatment of chronic hepatitis B and C.
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23
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Zhu H, Dong H, Eksioglu E, Hemming A, Cao M, Crawford JM, Nelson DR, Liu C. Hepatitis C virus triggers apoptosis of a newly developed hepatoma cell line through antiviral defense system. Gastroenterology 2007; 133:1649-59. [PMID: 17983809 DOI: 10.1053/j.gastro.2007.09.017] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 08/09/2007] [Indexed: 01/15/2023]
Abstract
BACKGROUND & AIMS Hepatitis C virus (HCV) has a tendency to cause chronic viral infection. Viral evasion of host immune systems plays a key role in the pathogenesis of HCV. However, the interaction between HCV and hepatocyte innate antiviral defense systems is not understood. The aim of this study was to examine how human hepatocytes respond to HCV infection. METHODS We have established a novel human hepatoma cell line, LH86, from a well-differentiated hepatocellular carcinoma tissue. An infectious HCV isolate, JFH-1, was used to infect LH86 cells. HCV replication and apoptosis after viral infection were examined. Mechanisms of HCV-induced apoptosis were determined. Type I interferon induction and the relevant signaling molecules were examined. RESULTS LH86 cells permitted JFH-1 HCV infection. The viral infection caused massive apoptosis. The apoptosis was related to viral replication, because blocking viral entry with anti-CD81 or suppressing viral replication with interferon protected cells from HCV-induced apoptosis. The HCV-induced apoptosis appeared to be triggered by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptors, death receptor 4 and death receptor 5, which were up-regulated in HCV infection. HCV also activated interferon response factor 3, which induced expression of interferon and TRAIL in LH86 cells. CONCLUSIONS Our study showed that a specific HCV isolate, JFH-1, is cytopathic in this new hepatoma cell line. LH86 cells mount an intact innate antiviral defense through induction of interferon and triggering apoptosis of infected cells. This study reveals a novel mechanism by which host hepatocytes respond to acute HCV infection.
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Affiliation(s)
- Haizhen Zhu
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
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Affiliation(s)
- Clara Balsano
- Dipartimento di Medicina Interna e Sanità Pubblica (MISP), University of L'Aquila, L'Aquila, Italy.
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Morikawa K, Zhao Z, Date T, Miyamoto M, Murayama A, Akazawa D, Tanabe J, Sone S, Wakita T. The roles of CD81 and glycosaminoglycans in the adsorption and uptake of infectious HCV particles. J Med Virol 2007; 79:714-23. [PMID: 17457918 DOI: 10.1002/jmv.20842] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Because appropriate cell-culture systems or small-animal models have been lacking, the early steps in the HCV life cycle have been difficult to study. A cell culture system was developed recently that allows production of infectious HCV. In this study, infectious HCV particles produced in cultured cells were used. To clarify the role of CD81 in HCV attachment and entry, the effect of anti-CD81 antibody was examined. The antibody blocked HCV virion entry but not particle attachment. Only the fraction bound to a heparin affinity column and eluted with 0.3 M NaCl productively infected Huh7 cells, indicating that infectious HCV particles bind to heparin. Both heparin treatment of the virus particles and heparinase treatment of the Huh7 cells reduced virus-cell binding without substantially inhibiting HCV infectivity. Finally, to confirm the role of both heparin sulfate proteoglycan (HSPG) and CD81 in HCV entry, the effects of heparinase I and anti-CD81 antibody were analyzed. No productive RNA replication was detected in the Huh7 cells in the presence of both heparinase I and anti-CD81 antibody. In conclusion, these data suggested that both HSPG and CD81 are important for HCV entry. HSPG may play a role in the initial cell surface binding of infectious HCV particles and CD81 is conceivably correlated with HCV entry after viral attachment.
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Affiliation(s)
- Kenichi Morikawa
- Department of Microbiology, Tokyo Metropolitan Institute for Neuroscience, Tokyo, Japan
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26
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Pawlotsky JM, Chevaliez S, McHutchison JG. The hepatitis C virus life cycle as a target for new antiviral therapies. Gastroenterology 2007; 132:1979-98. [PMID: 17484890 DOI: 10.1053/j.gastro.2007.03.116] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Accepted: 03/23/2007] [Indexed: 12/11/2022]
Abstract
The burden of disease consequent to hepatitis C virus (HCV) infection has been well described and is expected to increase dramatically over the next decade. Current approved antiviral therapies are effective in eradicating the virus in approximately 50% of infected patients. However, pegylated interferon and ribavirin-based therapy is costly, prolonged, associated with significant adverse effects, and not deemed suitable for many HCV-infected patients. As such, there is a clear and pressing need for the development of additional agents that act through alternate or different mechanisms, in the hope that such regimens could lead to enhanced response rates more broadly applicable to patients with hepatitis C infection. Recent basic science enhancements in HCV cell culture systems and replication assays have led to a broadening of our understanding of many of the mechanisms of HCV replication and, therefore, potential novel antiviral targets. In this article, we have attempted to highlight important new information as it relates to our understanding of the HCV life cycle. These steps broadly encompass viral attachment, entry, and fusion; viral RNA translation; posttranslational processing; HCV replication; and viral assembly and release. In each of these areas, we present up-to-date knowledge of the relevant aspects of that component of the viral life cycle and then describe the preclinical and clinical development targets and pathways being explored in the translational and clinical settings.
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Affiliation(s)
- Jean-Michel Pawlotsky
- French National Reference Center for Viral Hepatitis B, C, and delta, Department of Virology, Hôpital Henri Mondor, Université Paris 12, Créteil, France.
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Garcia JE, Fierro R, Puentes A, Cortés J, Bermúdez A, Cifuentes G, Vanegas M, Patarroyo ME. Monosaccharides modulate HCV E2 protein-derived peptide biological properties. Biochem Biophys Res Commun 2007; 355:409-18. [PMID: 17306766 DOI: 10.1016/j.bbrc.2007.01.167] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 01/30/2007] [Indexed: 11/20/2022]
Abstract
A hepatitis C virus E(2) protein-derived sequence was selected for studying the effect of N-glycosylation on the peptide chain's conformational structure. The results suggested that the (534)TDVF(537) motif contained in peptide 33402 ((529)WGENDTDVFVLNNTRY(544)) had a type III beta-turn, relevant in antigen recognition of polyclonal antibodies, binding to human cells, and binding to HLA DRB1 *0401 molecules. N-Glycopeptides derived from this sequence contained monosaccharides in Asn(532). N-Glycopeptides presented differences in peptide chain structure compared to non-glycosylated peptides. Peptide 33402 specifically bound to human cells, specificity becoming lost when it was N-glycosylated. N-Glycosylation decreased antigen recognition of mouse polyclonal sera against this sequence. N-Glycopeptide binding to HLA DRB1 *0401 molecules was similar to that presented by non-glycosylated peptide, indicating that N-glycosylation did not affect binding to HLA DRB1 *0401 molecules. N-Glycosylation induced changes at structural and functional level which could be relevant for modulating human cell binding properties and antibody recognition.
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Affiliation(s)
- Javier E Garcia
- Fundación Instituto de Immunología de Colombia, Carrera 50 #26-00, Bogotá, Colombia
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Abstract
Over the past several years, significant progress has been made toward the understanding of hepatitis C virus, especially the development of in vitro cell culture models. The scientific community now has the tools to gain a better understanding of the virus, which should translate into better clinical therapeutic modalities. Many new drugs are currently being evaluated, and a few are already undergoing clinica trials. This article focuses on the current advances in hepatitis C virus virology.
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Affiliation(s)
- Chen Liu
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, 1600 SW Archer Road, Gainesville, FL 32610, USA.
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29
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Owsianka AM, Timms JM, Tarr AW, Brown RJP, Hickling TP, Szwejk A, Bienkowska-Szewczyk K, Thomson BJ, Patel AH, Ball JK. Identification of conserved residues in the E2 envelope glycoprotein of the hepatitis C virus that are critical for CD81 binding. J Virol 2006; 80:8695-704. [PMID: 16912317 PMCID: PMC1563869 DOI: 10.1128/jvi.00271-06] [Citation(s) in RCA: 205] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Hepatitis C virus (HCV) cell entry involves interaction between the viral envelope glycoprotein E2 and the cell surface receptor CD81. Knowledge of conserved E2 determinants important for successful binding will facilitate development of entry inhibitors designed to block this interaction. Previous studies have assigned the CD81 binding function to a number of discontinuous regions of E2. To better define specific residues involved in receptor binding, a panel of mutants of HCV envelope proteins was generated, where conserved residues within putative CD81 binding regions were sequentially mutated to alanine. Mutant proteins were tested for binding to a panel of monoclonal antibodies and CD81 and for their ability to form noncovalent heterodimers and confer infectivity in the retroviral pseudoparticle (HCVpp) assay. Detection by conformation-sensitive monoclonal antibodies indicated that the mutant proteins were correctly folded. Mutant proteins fell into three groups: those that bound CD81 and conferred HCVpp infectivity, those that abrogated both CD81 binding and HCVpp infectivity, and a final group containing mutants that were able to bind CD81 but were noninfectious in the HCVpp assay. Specific amino acids conserved across all genotypes that were critical for CD81 binding were W420, Y527, W529, G530, and D535. These data significantly increase our understanding of the CD81 receptor-E2 binding process.
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Affiliation(s)
- Ania M Owsianka
- MRC Virology Unit, Institute of Virology, University of Glasgow, UK
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30
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Codran A, Royer C, Jaeck D, Bastien-Valle M, Baumert TF, Kieny MP, Pereira CA, Martin JP. Entry of hepatitis C virus pseudotypes into primary human hepatocytes by clathrin-dependent endocytosis. J Gen Virol 2006; 87:2583-2593. [PMID: 16894197 DOI: 10.1099/vir.0.81710-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Hepatitis C virus (HCV) is a major cause of chronic hepatitis worldwide. Studies of the early steps of HCV infection have been hampered by the lack of convenient in vitro or in vivo models. Although several cell-surface molecules that mediate the binding of HCV envelope proteins to target cells have been identified, mechanisms of viral entry into human hepatocytes are still poorly understood. Vesicular stomatitis virus/HCV pseudotyped viruses expressing the HCV envelope glycoproteins on the viral envelope were generated and it was found that their entry into human hepatocytes required co-expression of E1 and E2 on the pseudotype surface. Neutralization of pseudotype infection by anti-HCV antibodies suggested that cellular entry was mediated by HCV envelope glycoproteins and by previously characterized cell-surface molecules, including CD81. An entry assay based on the release of a fluorochrome from labelled HCV pseudotypes provided evidence for a pH-dependent fusion of the pseudotype envelope with a cellular compartment. By using a panel of endocytosis inhibitors, it is postulated that penetration of HCV into primary cultures of hepatocytes takes place by clathrin-mediated endocytosis.
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Affiliation(s)
- Audrey Codran
- INSERM U544, EA 3770, Institut de Virologie, Université Louis Pasteur, 3 rue Koeberlé, F-67000 Strasbourg, France
| | - Cathy Royer
- INSERM U544, EA 3770, Institut de Virologie, Université Louis Pasteur, 3 rue Koeberlé, F-67000 Strasbourg, France
| | - Daniel Jaeck
- Centre de Chirurgie Viscérale et de Transplantation, Centre Hospitalier de Hautepierre, F-67000 Strasbourg, France
| | - Michèle Bastien-Valle
- INSERM U544, EA 3770, Institut de Virologie, Université Louis Pasteur, 3 rue Koeberlé, F-67000 Strasbourg, France
| | - Thomas F Baumert
- Department of Medicine II, University of Freiburg, Hugstetter Straße 55, D-79106 Freiburg, Germany
| | - Marie Paule Kieny
- INSERM U544, EA 3770, Institut de Virologie, Université Louis Pasteur, 3 rue Koeberlé, F-67000 Strasbourg, France
| | | | - Jean-Pierre Martin
- INSERM U544, EA 3770, Institut de Virologie, Université Louis Pasteur, 3 rue Koeberlé, F-67000 Strasbourg, France
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El-Awady MK, Tabll AA, Atef K, Yousef SS, Omran MH, El-Abd Y, Bader-Eldin NG, Salem AM, Zohny SF, El-Garf WT. Antibody to E1 peptide of hepatitis C virus genotype 4 inhibits virus binding and entry to HepG2 cells in vitro. World J Gastroenterol 2006. [PMID: 16688798 DOI: 10.3748/wjg.v12.i16.2530.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/29/2022] Open
Abstract
AIM To analyze the neutralizing activity of antibodies against E1 region of hepatitis C virus (HCV). Specific polyclonal antibody was raised via immunization of New Zealand rabbits with a synthetic peptide that had been derived from the E1 region of HCV and was shown to be highly conserved among HCV published genotypes. METHODS Hyper-immune HCV E1 antibodies were incubated over night at 4 degree Celsius with serum samples positive for HCV RNA, with viral loads ranging from 615 to 3.2 million IU/ mL. Treated sera were incubated with HepG2 cells for 90 min. Blocking of viral binding and entry into cells by anti E1 antibody were tested by means of RT-PCR and flow cytometry. RESULTS Direct immunostaining using FITC conjugated E1 antibody followed by Flow cytometric analysis showed reduced mean fluorescence intensity in samples pre-incubated with E1 antibody compared with untreated samples. Furthermore, 13 out of 18 positive sera (72%) showed complete inhibition of infectivity as detected by RT-PCR. CONCLUSION In house produced E1 antibody, blocks binding and entry of HCV virion infection to target cells suggesting the involvement of this epitope in virus binding and entry. Isolation of these antibodies that block virus attachment to human cells are useful as therapeutic reagents.
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Affiliation(s)
- Mostafa K El-Awady
- Department of Biomedical Technology, National Research Center, Dokki, Cairo, Egypt.
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32
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El-Awady MK, Tabll AA, Atef K, Yousef SS, Omran MH, El-Abd Y, Bader-Eldin NG, Salem AM, Zohny SF, El-Garf WT. Antibody to E1 peptide of hepatitis C virus genotype 4 inhibits virus binding and entry to HepG2 cells in vitro. World J Gastroenterol 2006; 12:2530-5. [PMID: 16688798 PMCID: PMC4087985 DOI: 10.3748/wjg.v12.i16.2530] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Revised: 12/26/2005] [Accepted: 01/14/2006] [Indexed: 02/06/2023] Open
Abstract
AIM To analyze the neutralizing activity of antibodies against E1 region of hepatitis C virus (HCV). Specific polyclonal antibody was raised via immunization of New Zealand rabbits with a synthetic peptide that had been derived from the E1 region of HCV and was shown to be highly conserved among HCV published genotypes. METHODS Hyper-immune HCV E1 antibodies were incubated over night at 4 degree Celsius with serum samples positive for HCV RNA, with viral loads ranging from 615 to 3.2 million IU/ mL. Treated sera were incubated with HepG2 cells for 90 min. Blocking of viral binding and entry into cells by anti E1 antibody were tested by means of RT-PCR and flow cytometry. RESULTS Direct immunostaining using FITC conjugated E1 antibody followed by Flow cytometric analysis showed reduced mean fluorescence intensity in samples pre-incubated with E1 antibody compared with untreated samples. Furthermore, 13 out of 18 positive sera (72%) showed complete inhibition of infectivity as detected by RT-PCR. CONCLUSION In house produced E1 antibody, blocks binding and entry of HCV virion infection to target cells suggesting the involvement of this epitope in virus binding and entry. Isolation of these antibodies that block virus attachment to human cells are useful as therapeutic reagents.
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Affiliation(s)
- Mostafa K El-Awady
- Department of Biomedical Technology, National Research Center, Dokki, Cairo, Egypt.
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33
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Mazzocca A, Sciammetta SC, Carloni V, Cosmi L, Annunziato F, Harada T, Abrignani S, Pinzani M. Binding of hepatitis C virus envelope protein E2 to CD81 up-regulates matrix metalloproteinase-2 in human hepatic stellate cells. J Biol Chem 2004; 280:11329-39. [PMID: 15611113 DOI: 10.1074/jbc.m410161200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The hepatitis C virus (HCV) envelope E2 glycoprotein is a key molecule regulating the interaction of HCV with cell surface proteins. E2 binds the major extracellular loop of human CD81, a tetraspanin expressed on various cell types including hepatocytes and B lymphocytes. Regardless, information on the biological functions originating from this interaction are largely unknown. Since human hepatic stellate cells (HSC) express high levels of CD81 at the cell surface, we investigated the E2/CD81 interaction in human HSC and the possible effects arising from this interaction. Matrix metalloproteinase-2 (MMP-2; gelatinase A), a major enzyme involved in the degradation of normal hepatic extracellular matrix, was up-regulated following the interaction between E2 and CD81. In particular, by employing zymography and Western blot, we observed that E2 binding to CD81 induces a time-dependent increase in the synthesis and activity of MMP-2. This effect was abolished by preincubating HSC with an anti-CD81 neutralizing antibody. Similar effects were detected in NIH3T3 mouse fibroblasts transfected with human CD81 with identical time course features. In addition, E2/CD81 interaction in human HSC induced the up-regulation of MMP-2 by increasing activator protein-2/DNA binding activity via ERK/MAPK phosphorylation. Finally, suppression of CD81 by RNA interference in human HSC abolished the described effects of E2 on these cells, indicating that CD81 is essential for the activation of the signaling pathway leading to the up-regulation of MMP-2. These results suggest that HSC may represent a potential target for HCV. The interaction of HCV envelope with CD81 on the surface of human HSC induces an increased expression of MMP-2. Increased degradation of the normal hepatic extracellular matrix in areas where HCV is concentrated may favor inflammatory infiltration and further parenchymal damage.
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Affiliation(s)
- Antonio Mazzocca
- Dipartimento di Medicina Interna, Centro di Ricerca, Trasferimento e Alta Formazione MCIDNENT Università di Firenze, I-50134 Firenze, Italy.
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34
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Kronenberger B, Sarrazin C, Hofmann WP, von Wagner M, Herrmann E, Welsch C, Elez R, Rüster B, Piiper A, Zeuzem S. Mutations in the putative HCV-E2 CD81 binding regions and correlation with cell surface CD81 expression. J Viral Hepat 2004; 11:310-8. [PMID: 15230853 DOI: 10.1111/j.1365-2893.2004.00508.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The hepatitis C virus (HCV) envelope (E)2 protein interacts with the cellular receptor CD81 leading to modulation of B and T cell function. Recently, a higher binding affinity of subtype 1a in comparison with 1b derived E2 proteins for CD81 in vitro was described. The importance of mutations within the putative CD81 binding regions of different HCV geno-/subtypes in correlation with CD81 expression is unknown. In the present study, CD81 expression on blood lymphocytes of patients with chronic hepatitis C infected with different HCV geno-/subtypes were analysed by fluorescence activated cell sorter analyses. In addition, the putative CD81 binding regions on the E2 gene comprising the hypervariable region (HVR)2 were analysed by direct sequencing. CD81 expression on CD8(+) T-lymphocytes from patients infected with subtype 1a (n = 6) was significantly higher in comparison with subtype 1b (n = 12) and 3 (n = 5) infected patients before and during antiviral therapy (P = 0.006; P = 0.021, respectively). Sequencing of the putative CD81 binding regions in the E2 protein comprising the HVR2 (codon 474-495 and 522-552 according to the HCV-1a prototype HCV-H) showed a highly conserved motif within HVR2 for subtype 1a isolates and an overall low number of mutations within the putative CD81 binding regions, whereas numerous mutations were detected for subtype 1b isolates (12.0 vs 23.6%). HCV-3 isolates showed an intermediate number of mutations within the putative binding sites (19.2%; P = 0.022). In conclusion, the highly conserved sequence within HVR2 and putative CD81 binding sites of subtype 1a isolates previously associated with a high CD81 binding affinity in vitro is correlated with high CD81 expression on CD8(+) T-lymphocytes in vivo.
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Affiliation(s)
- B Kronenberger
- Klinik für Innere Medizin II, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany
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35
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Heo TH, Chang JH, Lee JW, Foung SKH, Dubuisson J, Kang CY. Incomplete Humoral Immunity against Hepatitis C Virus Is Linked with Distinct Recognition of Putative Multiple Receptors by E2 Envelope Glycoprotein. THE JOURNAL OF IMMUNOLOGY 2004; 173:446-55. [PMID: 15210804 DOI: 10.4049/jimmunol.173.1.446] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Little is known about the role of the humoral immune response to hepatitis C virus (HCV). This study provides molecular evidence for the mechanism by which neutralizing Abs from the sera of chronic HCV patients have lower inhibitory activities against the binding of HCV E2 envelope protein to human hepatoma cell lines than to a lymphoma cell line. E2 binds to several putative receptors, specifically human CD81; human scavenger receptor, class B, type 1; and heparan sulfate. We have shown that E2 binds to target cells via these receptors in a noncompetitive manner. Thus, incomplete inhibition of one of the receptors leads to only a partial E2 blockade and, possibly, evasion of the host immune response. We demonstrated that the difference in and reduction of inhibition was closely related to impaired blockade of E2 binding to scavenger receptor, class B, type 1, and heparan sulfate. We have also shown that soluble E2 protein binds to multiple soluble receptors via separate binding domains on E2, providing further evidence for the distinct recognition of multiple cellular receptors by E2. This report suggests a novel finding that biased humoral immune responses to HCV E2 might provide an alternative mechanism for viral escape without the involvement of mutation. Additionally, our data give crucial consideration to the development of HCV vaccines that stimulate protective humoral immune responses.
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Affiliation(s)
- Tae-Hwe Heo
- Laboratory of Immunology, Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742, Korea
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36
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Tutuncu L, Stein P, Ord TS, Jorgez CJ, Williams CJ. Calreticulin on the mouse egg surface mediates transmembrane signaling linked to cell cycle resumption. Dev Biol 2004; 270:246-60. [PMID: 15136153 DOI: 10.1016/j.ydbio.2004.02.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2003] [Revised: 02/09/2004] [Accepted: 02/11/2004] [Indexed: 11/25/2022]
Abstract
Calreticulin, a protein best known as an endoplasmic reticulum chaperone, also is found on the extracellular plasma membrane surface of many cell types where it serves as a mediator of adhesion and as a regulator of the immune response. In this report, we demonstrate that calreticulin is present on the extracellular surface of the mouse egg plasma membrane and is increased in the perivitelline space after egg activation. The extracellular calreticulin appears to be secreted by vesicles in the egg cortex that are distinct from cortical granules. An anticalreticulin antibody binds to extracellular calreticulin on live eggs and inhibits sperm-egg binding but not fusion. In addition, engagement of cell surface calreticulin by incubation of mouse eggs in the presence of anticalreticulin antibodies results in alterations in the localization of cortical actin and the resumption of meiosis as indicated by alterations in chromatin configuration, decreases in cdc2/cyclin B1 and MAP kinase activities, and pronuclear formation. These events occur in the absence of any observable alterations in intercellular calcium. These data demonstrate that calreticulin functionally interacts with the egg cytoskeleton and can mediate transmembrane signaling linked to cell cycle resumption. These studies suggest a role for calreticulin as a lectin that may be involved in signal transduction events during or after sperm-egg interactions at fertilization.
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Affiliation(s)
- Levent Tutuncu
- Center for Research on Reproduction and Women's Health, University of Pennsylvania, Philadelphia, PA 19104, USA
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37
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Barth H, Schafer C, Adah MI, Zhang F, Linhardt RJ, Toyoda H, Kinoshita-Toyoda A, Toida T, Van Kuppevelt TH, Depla E, Von Weizsacker F, Blum HE, Baumert TF. Cellular binding of hepatitis C virus envelope glycoprotein E2 requires cell surface heparan sulfate. J Biol Chem 2003; 278:41003-12. [PMID: 12867431 DOI: 10.1074/jbc.m302267200] [Citation(s) in RCA: 368] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The conservation of positively charged residues in the N terminus of the hepatitis C virus (HCV) envelope glycoprotein E2 suggests an interaction of the viral envelope with cell surface glycosaminoglycans. Using recombinant envelope glycoprotein E2 and virus-like particles as ligands for cellular binding, we demonstrate that cell surface heparan sulfate proteoglycans (HSPG) play an important role in mediating HCV envelope-target cell interaction. Heparin and liver-derived highly sulfated heparan sulfate but not other soluble glycosaminoglycans inhibited cellular binding and entry of virus-like particles in a dose-dependent manner. Degradation of cell surface heparan sulfate by pretreatment with heparinases resulted in a marked reduction of viral envelope protein binding. Surface plasmon resonance analysis demonstrated a high affinity interaction (KD 5.2 x 10-9 m) of E2 with heparin, a structural homologue of highly sulfated heparan sulfate. Deletion of E2 hypervariable region-1 reduced E2-heparin interaction suggesting that positively charged residues in the N-terminal E2 region play an important role in mediating E2-HSPG binding. In conclusion, our results demonstrate for the first time that cellular binding of HCV envelope requires E2-HSPG interaction. Docking of E2 to cellular HSPG may be the initial step in the interaction between HCV and the cell surface resulting in receptor-mediated entry and initiation of infection.
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Affiliation(s)
- Heidi Barth
- Department of Medicine II, University of Freiburg, D-79106 Freiburg, Germany
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38
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Bélec L, Legoff J, Si-Mohamed A, Bloch F, Mbopi Keou FX, Becquart P, Matta M, Prazuck T, Petite JP, Gutmann L, Payan C. Mucosal humoral immune response to hepatitis C virus E1/E2 surface glycoproteins and HCV shedding in saliva and cervicovaginal fluids from chronically HCV-infected patients. J Hepatol 2003; 38:833-42. [PMID: 12763378 DOI: 10.1016/s0168-8278(03)00119-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS We herein focused on identifying biological factors possibly involved in non-parenteral transmission of hepatitis C virus (HCV), such as HCV excretion patterns and antibody-based immunity to the virus in saliva and/or cervicovaginal secretions (CVS). METHODS Paired blood, saliva and cervicovaginal lavage samples were obtained from HCV-RNA plasma-positive hemoglobin (Hb) antigen and HIV-seronegative, HCV-seropositive males (n=13) and females (n=21). HCV-specific antibodies were detected by ELISA in paired samples, and HCV-RNA was detected in cell-free and cell-associated body fluids. RESULTS Antibodies to E1 HCV surface glycoprotein of the IgG and IgA isotypes showed similar, but less pronounced, profiles as IgG and IgA to E2. HCV-specific IgG and IgA in mucosal fluids likely originated predominantly from the systemic compartment, because HCV-specific mucosal immunoglobulins involved primarily monomeric antibodies, including monomeric IgA, and because their specific activities for HCV antigens in corporeal fluids were similar to those in paired serum (Se). Viral shedding in saliva or CVS was restricted to cell-associated, non-replicating strand((+)) HCV-RNA in 42% (12 out of 28) of saliva and in 19% (four out of 21) of cervicovaginal fluids. CONCLUSIONS The association in body fluids of HCV-specific IgG, and to a lesser extent IgA, directed to E1/E2 surface glycoproteins (which may block critical steps of virus-cell interactions), of undetectable free viral RNA, and of occasional non-replicating cell-associated HCV, suggests a resulting poor infectivity of saliva or cervicovaginal fluid in chronically HCV-infected individuals. Taken together, these observations provide the basis for the low risk of non-parenteral transmission of HCV infection.
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Affiliation(s)
- Laurent Bélec
- Unité INSERM U430 (Immunopathologie humaine), hôpital Broussais, and Université Pierre and Marie Curie (Paris VI), Paris, France.
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39
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Lozach PY, Lortat-Jacob H, de Lacroix de Lavalette A, Staropoli I, Foung S, Amara A, Houles C, Fieschi F, Schwartz O, Virelizier JL, Arenzana-Seisdedos F, Altmeyer R. DC-SIGN and L-SIGN are high affinity binding receptors for hepatitis C virus glycoprotein E2. J Biol Chem 2003; 278:20358-66. [PMID: 12609975 DOI: 10.1074/jbc.m301284200] [Citation(s) in RCA: 285] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The hepatitis C virus (HCV) genome codes for highly mannosylated envelope proteins, which are naturally retained in the endoplasmic reticulum. We found that the HCV envelope glycoprotein E2 binds the dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) and the related liver endothelial cell lectin L-SIGN through high-mannose N-glycans. Competing ligands such as mannan and an antibody directed against the carbohydrate recognition domains (CRD) abrogated binding. While no E2 interaction with distant monomeric CRDs on biosensor chips could be detected, binding is observed if CRDs are closely seeded (Kd = 48 nm) and if the CRD is part of the oligomeric-soluble extracellular domain of DC-SIGN (Kd = 30 nm). The highest affinity is seen for plasma membrane-expressed DC-SIGN and L-SIGN (Kd = 3 and 6 nm, respectively). These results indicate that several high-mannose N-glycans in a structurally defined cluster on E2 bind to several subunits of the oligomeric lectin CRD. High affinity interaction of viral glycoproteins with oligomeric lectins might represent a strategy by which HCV targets to and concentrates in the liver and infects dendritic cells.
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Affiliation(s)
- Pierre-Yves Lozach
- Unité d'Immunologie Virale, Institut Pasteur, 28, rue du Dr. Roux, 75015 Paris, France
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40
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Gardner JP, Durso RJ, Arrigale RR, Donovan GP, Maddon PJ, Dragic T, Olson WC. L-SIGN (CD 209L) is a liver-specific capture receptor for hepatitis C virus. Proc Natl Acad Sci U S A 2003; 100:4498-503. [PMID: 12676990 PMCID: PMC153584 DOI: 10.1073/pnas.0831128100] [Citation(s) in RCA: 230] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2002] [Accepted: 02/25/2003] [Indexed: 01/13/2023] Open
Abstract
Hepatitis C virus (HCV) infects nearly 3% of the population of the world and is a major cause of liver disease. However, the mechanism whereby the virus targets the liver for infection remains unknown, because none of the putative cellular receptors for HCV are both expressed specifically in the liver and capable of binding HCV envelope glycoproteins. Liver/lymph node-specific intercellular adhesion molecule-3-grabbing integrin (L-SIGN) is a calcium-dependent lectin expressed on endothelial cells of liver and lymph nodes. Dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), a homologous molecule expressed on dendritic cells, binds HIV and promotes infection. By using a virus-binding assay, we demonstrate that L-SIGN and DC-SIGN specifically bind naturally occurring HCV present in the sera of infected individuals. Further studies demonstrate that binding is mediated by the HCV envelope glycoprotein E2 and is blocked by specific inhibitors, including mannan, calcium chelators, and Abs to the lectin domain of the SIGN molecules. Thus, L-SIGN represents a liver-specific receptor for HCV, and L-SIGN and DC-SIGN may play important roles in HCV infection and immunity.
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Affiliation(s)
- Jason P Gardner
- Progenics Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA.
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41
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Tan YJ, Lim SP, Ng P, Goh PY, Lim SG, Tan YH, Hong W. CD81 engineered with endocytotic signals mediates HCV cell entry: implications for receptor usage by HCV in vivo. Virology 2003; 308:250-69. [PMID: 12706076 DOI: 10.1016/s0042-6822(02)00136-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Although CD81 has been shown to bind HCV E2 protein, its role as a receptor for HCV remains controversial. In this study, we constructed two CD81 chimeras by linking the cytoplasmic domains of recycling surface receptors, low-density lipoprotein receptor (LDLR), and transferrin receptor (TfR), respectively, to CD81 and compared their internalization properties to wild-type CD81. Binding experiments with anti-hCD81 antibody showed that cell-surface CD81 chimeric receptors were internalized much more efficiently than wild-type CD81. In addition, CD81 chimeras, but not wild-type CD81, could internalize recombinant E2 protein and E2-enveloped viral particles from the serum of HCV-infected patients into Huh7 liver cells. The latter resulted in persistent positive-strand viral RNA and accumulation of replication intermediates, negative-strand viral RNA, in the infected cells, suggesting that the internalized viruses have undergone replication. Therefore, it appeared that CD81, possibly in association with a liver-specific endocytotic protein(s), represents one of the pathways by which HCV can infect hepatocytes.
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Affiliation(s)
- Yee-Joo Tan
- Collaborative Anti-Viral Research Group, Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609.
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42
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Zoulim F, Chevallier M, Maynard M, Trepo C. Clinical consequences of hepatitis C virus infection. Rev Med Virol 2003; 13:57-68. [PMID: 12516062 DOI: 10.1002/rmv.371] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) is a positive strand RNA virus that belongs to the Hepacivirinae genus within the Flaviviridae family. HCV infection has a wide spectrum of cellular tropism and clinical presentations. This has major impacts in terms of pathogenesis and diagnosis. Consequently, a wide range of clinical consequences characterises this viral infection, including asymptomatic chronic carriage, acute hepatitis, chronic hepatitis, cirrhosis, hepatocellular carcinoma and extrahepatic manifestations. The latter are commonly observed and may represent the first sign of the disease. A better knowledge of the pathobiology of HCV and its clinical consequences will be important for developing better treatment strategies to cure HCV infection and extrahepatic manifestations.
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Affiliation(s)
- F Zoulim
- INSERM U 271, 151 Cours Albert Thomas, 69424 Lyon Cedex 03, France.
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43
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Sanz-Cameno P, Borque MJ, García-Buey L, Moreno-Otero R. [Interaction of the hepatitis C virus with the cellular membrane]. GASTROENTEROLOGIA Y HEPATOLOGIA 2002; 25:521-5. [PMID: 12361536 DOI: 10.1016/s0210-5705(02)70304-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- P Sanz-Cameno
- Unidad de Biología Molecular, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, España
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44
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Lambot M, Frétier S, Op De Beeck A, Quatannens B, Lestavel S, Clavey V, Dubuisson J. Reconstitution of hepatitis C virus envelope glycoproteins into liposomes as a surrogate model to study virus attachment. J Biol Chem 2002; 277:20625-30. [PMID: 11937498 DOI: 10.1074/jbc.m111020200] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The envelope glycoproteins, E1 and E2, of hepatitis C virus (HCV) assemble intracellularly to form a noncovalent heterodimer that is expected to be essential for viral assembly and entry. However, due to the lack of a cell culture system supporting efficient HCV replication, it is very difficult to obtain relevant information on the functions of this glycoprotein oligomer. To get better insights into its biological and biochemical properties, HCV envelope glycoprotein heterodimer expressed by a vaccinia virus recombinant was purified by immunoaffinity. Purified E1E2 heterodimer was recognized by conformation-dependent monoclonal antibodies, showing that the proteins were properly folded. In addition, it interacted with human CD81, a putative HCV receptor, as well as with human low and very low density lipoproteins, which have been shown to be associated with infectious HCV particles isolated from patients. Purified E1E2 heterodimer was also reconstituted into liposomes. E1E2-liposomes were recognized by a conformation-dependent monoclonal antibody as well as by human CD81. Together, these data indicate that E1E2-liposomes are a valuable tool to study the molecular requirements for HCV binding to target cells.
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Affiliation(s)
- Michel Lambot
- CNRS-Institut de Biologie de Lille & Institut Pasteur de Lille, 59021 Lille Cedex, France
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45
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Olenina LV, Nikolaeva LI, Sobolev BN, Blokhina NP, Archakov AI, Kolesanova EF. Mapping and characterization of B cell linear epitopes in the conservative regions of hepatitis C virus envelope glycoproteins. J Viral Hepat 2002; 9:174-82. [PMID: 12010504 DOI: 10.1046/j.1365-2893.2002.00358.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Forty-eight overlapping octapeptides covering highly conservative regions of E1 and E2 hepatitis C virus (HCV) envelope proteins were synthesized and tested by ELISA against different groups of sera obtained from HCV-infected patients. All sera from patients with acute infection, except a single case of serum reactivity with the region HINRTALN, were nonreactive with any peptide. Sera obtained from chronic patients reacted with 12 peptides from five selected regions. Two immunodominant B epitopes were found, one being the precisely mapped antigenic site RMAWDM positioned inside the earlier shown immunodominant epitope from E1, and the second site, PALSTGLIH from E2, detected for the first time. New minor antigenic site was determined as PTDCFRKH from E2. We found only minor seroreactivity for one of the putative sites involved in CD81 binding, PYCWHYAP.
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Affiliation(s)
- L V Olenina
- Institute of Biomedical Chemistry, Russian Academy of Medical Science, Moscow, Russia.
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Wellnitz S, Klumpp B, Barth H, Ito S, Depla E, Dubuisson J, Blum HE, Baumert TF. Binding of hepatitis C virus-like particles derived from infectious clone H77C to defined human cell lines. J Virol 2002; 76:1181-93. [PMID: 11773394 PMCID: PMC135804 DOI: 10.1128/jvi.76.3.1181-1193.2002] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) is a leading cause of chronic hepatitis in the world. The study of viral entry and infection has been hampered by the inability to efficiently propagate the virus in cultured cells and the lack of a small-animal model. Recent studies have shown that in insect cells, the HCV structural proteins assemble into HCV-like particles (HCV-LPs) with morphological, biophysical, and antigenic properties similar to those of putative virions isolated from HCV-infected humans. In this study, we used HCV-LPs derived from infectious clone H77C as a tool to examine virus-cell interactions. The binding of partially purified particles to human cell lines was analyzed by fluorescence-activated cell sorting with defined monoclonal antibodies to envelope glycoprotein E2. HCV-LPs demonstrated dose-dependent and saturable binding to defined human lymphoma and hepatoma cell lines but not to mouse cell lines. Binding could be inhibited by monoclonal anti-E2 antibodies, indicating that the HCV-LP-cell interaction was mediated by envelope glycoprotein E2. Binding appeared to be CD81 independent and did not correlate with low-density lipoprotein receptor expression. Heat denaturation of HCV-LPs drastically reduced binding, indicating that the interaction of HCV-LPs with target cells was dependent on the proper conformation of the particles. In conclusion, our data demonstrate that insect cell-derived HCV-LPs bind specifically to defined human cell lines. Since the envelope proteins of HCV-LPs are presumably presented in a virion-like conformation, the binding of HCV-LPs to target cells may allow the study of virus-host cell interactions, including the isolation of HCV receptor candidates and antibody-mediated neutralization of binding.
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Affiliation(s)
- Sabine Wellnitz
- Department of Medicine II, University of Freiburg, Freiburg, Germany
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Op De Beeck A, Cocquerel L, Dubuisson J. Biogenesis of hepatitis C virus envelope glycoproteins. J Gen Virol 2001; 82:2589-2595. [PMID: 11602769 DOI: 10.1099/0022-1317-82-11-2589] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Anne Op De Beeck
- Equipe Hépatite C, CNRS-FRE2369, IBL/Institut Pasteur de Lille, 1 rue Calmette, BP 447, 59021 Lille cedex, France1
| | - Laurence Cocquerel
- Equipe Hépatite C, CNRS-FRE2369, IBL/Institut Pasteur de Lille, 1 rue Calmette, BP 447, 59021 Lille cedex, France1
| | - Jean Dubuisson
- Equipe Hépatite C, CNRS-FRE2369, IBL/Institut Pasteur de Lille, 1 rue Calmette, BP 447, 59021 Lille cedex, France1
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48
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Abstract
Since the genomic sequence of HCV was determined, significant progress has been made towards understanding the functions of the HCV-encoded proteins, despite the lack of an efficient in-vitro replication system or convenient small-animal model. The identity of the receptor for HCV remains elusive, however. Low-density lipoprotein receptor, CD81, and GAGs may all act as receptors for HCV, either sequentially or by different viral quasispecies. Recent work using pseudotypic VSV bearing E1 or E2 chimeric molecules showed that entry of the E1 pseudotype can be inhibited by recombinant LDLr, whereas the E2 pseudotype is more sensitive to inhibition by recombinant CD81 or heparin. These results suggest that E1 and E2 may be responsible for interactions with different cellular molecules. It is also conceivable that additional, yet unidentified, cellular proteins are involved in viral binding and entry. Intriguingly, the reports of HCV-RNA associated with PBMC suggest that HCV infection may not be restricted to hepatocytes. Thus, separate reservoirs of virus may exist, and HCV may use different receptors to access these different cell types.
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Affiliation(s)
- M Flint
- Division of Oncology, Department of Medicine, Stanford University Medical Center, Stanford, California, USA
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Abstract
HAART has increased the life expectancy of patients with HIV. However, as their life expectancy increases, it becomes increasingly important to focus on the management of concurrent illnesses such as chronic HBV and HCV infections which have the potential to increase mid to long term morbidity and mortality. Shared epidemiological risks have resulted in the HIV infected population having a higher incidence of both HBV and HCV than those uninfected with HIV. Co-infection with HIV modifies the natural history of HBV infection, increasing the rate of viral replication, risk of carriage and chronic hepatitis but without increasing liver necroinflammatory processes. In chronic HCV infection, the presence of HIV enhances the risk of severe liver disease. There is no evidence as yet that HBV directly impacts on HIV disease progression but HCV infection increases the risk of death or an AIDS defining illness and impairs CD4+ T cell recovery during antiretroviral therapy. Treatment of either hepatitis virus is complex because of pharmacokinetic interactions with components of HAART regimens.
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Affiliation(s)
- E Herrero Martínez
- Department of Virology and Haemophilia Centre, Royal Free and University College Medical School, London NW3 2PF, UK.
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50
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Penin F, Combet C, Germanidis G, Frainais PO, Deléage G, Pawlotsky JM. Conservation of the conformation and positive charges of hepatitis C virus E2 envelope glycoprotein hypervariable region 1 points to a role in cell attachment. J Virol 2001; 75:5703-10. [PMID: 11356980 PMCID: PMC114285 DOI: 10.1128/jvi.75.12.5703-5710.2001] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a major cause of liver disease. The HCV polyprotein contains a hypervariable region (HVR1) located at the N terminus of the second envelope glycoprotein E2. The strong variability of this 27-amino-acid region is due to its apparent tolerance of amino acid substitutions together with strong selection pressures exerted by anti-HCV immune responses. No specific function has so far been attributed to HVR1. However, its presence at the surface of the viral particle suggests that it might be involved in viral entry. This would imply that HVR1 is not randomly variable. We sequenced 460 HVR1 clones isolated at various times from six HCV-infected patients receiving alpha interferon therapy (which exerts strong pressure towards quasispecies genetic evolution) and analyzed their amino acid sequences together with those of 1,382 nonredundant HVR1 sequences collected from the EMBL database. We found that (i) despite strong amino acid sequence variability related to strong pressures towards change, the chemicophysical properties and conformation of HVR1 were highly conserved, and (ii) HVR1 is a globally basic stretch, with the basic residues located at specific sequence positions. This conservation of positively charged residues indicates that HVR1 is involved in interactions with negatively charged molecules such as lipids, proteins, or glycosaminoglycans (GAGs). As with many other viruses, possible interaction with GAGs probably plays a role in host cell recognition and attachment.
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Affiliation(s)
- F Penin
- Institut de Biologie et Chimie des Protéines, CNRS-UMR 5086, 69367 Lyon, France. f.
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