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Kumar N, Sharma S, Kumar R, Meena VK, Barua S. Evolution of drug resistance against antiviral agents that target cellular factors. Virology 2024; 600:110239. [PMID: 39276671 DOI: 10.1016/j.virol.2024.110239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Revised: 07/29/2024] [Accepted: 09/09/2024] [Indexed: 09/17/2024]
Abstract
Antiviral drugs have classically been developed by directly disrupting the functions of viral proteins. However, this strategy has been largely unsuccessful due to the rapid generation of viral escape mutants. It has been well established that as compared to the virus-centric approach, the strategy of developing antiviral drugs by targeting host-dependency factors (HDFs) minimizes drug resistance. However, recent reports have indicated that drug resistance against some of the host-targeting antiviral agents can in fact occur under some circumstances. Long-term selection pressure of a host-targeting antiviral agent may induce the virus to use an alternate cellular factor or alters its affinity towards the target that confers resistance. Alternatively, virus may synchronize its life cycle with the patterns of drug therapy. In addition, virus may subvert host's immune system to perpetuate under the limiting conditions of the targeted cellular factor. This review describes novel potential mechanisms that may account for the acquiring resistance against agents that target HDFs.
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Affiliation(s)
- Naveen Kumar
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, India.
| | - Shalini Sharma
- Department of Veterinary Physiology and Biochemistry, College of Veterinary Sciences, Sher-e-Kashmir University of Agricultural Sciences and Technology (SKAUST), Jammu, India.
| | - Ram Kumar
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, India
| | | | - Sanjay Barua
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, India
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2
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Carriquí-Madroñal B, Lasswitz L, von Hahn T, Gerold G. Genetic and pharmacological perturbation of hepatitis-C virus entry. Curr Opin Virol 2023; 62:101362. [PMID: 37678113 DOI: 10.1016/j.coviro.2023.101362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 06/30/2023] [Accepted: 08/08/2023] [Indexed: 09/09/2023]
Abstract
Hepatitis-C virus (HCV) chronically infects 58 million individuals worldwide with variable disease outcome. While a subfraction of individuals exposed to the virus clear the infection, the majority develop chronic infection if untreated. Another subfraction of chronically ill proceeds to severe liver disease. The underlying causes of this interindividual variability include genetic polymorphisms in interferon genes. Here, we review available data on the influence of genetic or pharmacological perturbation of HCV host dependency factors on the clinically observed interindividual differences in disease outcome. We focus on host factors mediating virus entry into human liver cells. We assess available data on genetic variants of the major entry factors scavenger receptor class-B type I, CD81, claudin-1, and occludin as well as pharmacological perturbation of these entry factors. We review cell culture experimental and clinical cohort study data and conclude that entry factor perturbation may contribute to disease outcome of hepatitis C.
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Affiliation(s)
- Belén Carriquí-Madroñal
- Department of Biochemistry & Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hanover, Hanover, Germany; Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hanover, Germany
| | - Lisa Lasswitz
- Department of Biochemistry & Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hanover, Hanover, Germany; Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hanover, Germany
| | - Thomas von Hahn
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, 30625 Hannover, Germany; Department of Gastroenterology, Hepatology and Interventional Endoscopy, Asklepios Hospital Barmbek, Semmelweis University, Campus Hamburg, 22307 Hamburg, Germany
| | - Gisa Gerold
- Department of Biochemistry & Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hanover, Hanover, Germany; Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hanover, Germany; Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, Umeå, Sweden; Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden.
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3
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Bailly C, Thuru X. Targeting of Tetraspanin CD81 with Monoclonal Antibodies and Small Molecules to Combat Cancers and Viral Diseases. Cancers (Basel) 2023; 15:cancers15072186. [PMID: 37046846 PMCID: PMC10093296 DOI: 10.3390/cancers15072186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/04/2023] [Accepted: 04/04/2023] [Indexed: 04/14/2023] Open
Abstract
Tetraspanin CD81 plays major roles in cell-cell interactions and the regulation of cellular trafficking. This cholesterol-embarking transmembrane protein is a co-receptor for several viruses, including HCV, HIV-1 and Chikungunya virus, which exploits the large extracellular loop EC2 for cell entry. CD81 is also an anticancer target implicated in cancer cell proliferation and mobility, and in tumor metastasis. CD81 signaling contributes to the development of solid tumors (notably colorectal, liver and gastric cancers) and has been implicated in the aggressivity of B-cell lymphomas. A variety of protein partners can interact with CD81, either to regulate attachment and uptake of viruses (HCV E2, claudin-1, IFIM1) or to contribute to tumor growth and dissemination (CD19, CD44, EWI-2). CD81-protein interactions can be modulated with molecules targeting the extracellular domain of CD81, investigated as antiviral and/or anticancer agents. Several monoclonal antibodies anti-CD81 have been developed, notably mAb 5A6 active against invasion and metastasis of triple-negative breast cancer cells. CD81-EC2 can also be targeted with natural products (trachelogenin and harzianoic acids A-B) and synthetic compounds (such as benzothiazole-quinoline derivatives). They are weak CD81 binders but offer templates for the design of new compounds targeting the open EC2 loop. There is no anti-CD81 compound in clinical development at present, but this structurally well-characterized tetraspanin warrants more substantial considerations as a drug target.
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Affiliation(s)
- Christian Bailly
- OncoWitan, Scientific Consulting Office, F-59290 Lille, France
- Institut de Chimie Pharmaceutique Albert Lespagnol (ICPAL), Faculty of Pharmacy, University of Lille, F-59006 Lille, France
- CNRS, Inserm, CHU Lille, UMR9020-U1277-Canther-Cancer Heterogeneity Plasticity and Resistance to Therapies, OncoLille Institut, University of Lille, F-59000 Lille, France
| | - Xavier Thuru
- CNRS, Inserm, CHU Lille, UMR9020-U1277-Canther-Cancer Heterogeneity Plasticity and Resistance to Therapies, OncoLille Institut, University of Lille, F-59000 Lille, France
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4
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Li HC, Yang CH, Lo SY. Cellular factors involved in the hepatitis C virus life cycle. World J Gastroenterol 2021; 27:4555-4581. [PMID: 34366623 PMCID: PMC8326260 DOI: 10.3748/wjg.v27.i28.4555] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/04/2021] [Accepted: 07/09/2021] [Indexed: 02/06/2023] Open
Abstract
The hepatitis C virus (HCV), an obligatory intracellular pathogen, highly depends on its host cells to propagate successfully. The HCV life cycle can be simply divided into several stages including viral entry, protein translation, RNA replication, viral assembly and release. Hundreds of cellular factors involved in the HCV life cycle have been identified over more than thirty years of research. Characterization of these cellular factors has provided extensive insight into HCV replication strategies. Some of these cellular factors are targets for anti-HCV therapies. In this review, we summarize the well-characterized and recently identified cellular factors functioning at each stage of the HCV life cycle.
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Affiliation(s)
- Hui-Chun Li
- Department of Biochemistry, Tzu Chi University, Hualien 970, Taiwan
| | - Chee-Hing Yang
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
| | - Shih-Yen Lo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
- Department of Laboratory Medicine, Buddhist Tzu Chi General Hospital, Hualien 970, Taiwan
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5
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Palor M, Stejskal L, Mandal P, Lenman A, Alberione MP, Kirui J, Moeller R, Ebner S, Meissner F, Gerold G, Shepherd AJ, Grove J. Cholesterol sensing by CD81 is important for hepatitis C virus entry. J Biol Chem 2020; 295:16931-16948. [PMID: 32900848 PMCID: PMC7863897 DOI: 10.1074/jbc.ra120.014761] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/11/2020] [Indexed: 01/12/2023] Open
Abstract
CD81 plays a central role in a variety of physiological and pathological processes. Recent structural analysis of CD81 indicates that it contains an intramembrane cholesterol-binding pocket and that interaction with cholesterol may regulate a conformational switch in the large extracellular domain of CD81. Therefore, CD81 possesses a potential cholesterol-sensing mechanism; however, its relevance for protein function is thus far unknown. In this study we investigate CD81 cholesterol sensing in the context of its activity as a receptor for hepatitis C virus (HCV). Structure-led mutagenesis of the cholesterol-binding pocket reduced CD81-cholesterol association but had disparate effects on HCV entry, both reducing and enhancing CD81 receptor activity. We reasoned that this could be explained by alterations in the consequences of cholesterol binding. To investigate this further we performed molecular dynamic simulations of CD81 with and without cholesterol; this identified a potential allosteric mechanism by which cholesterol binding regulates the conformation of CD81. To test this, we designed further mutations to force CD81 into either the open (cholesterol-unbound) or closed (cholesterol-bound) conformation. The open mutant of CD81 exhibited reduced HCV receptor activity, whereas the closed mutant enhanced activity. These data are consistent with cholesterol sensing switching CD81 between a receptor active and inactive state. CD81 interactome analysis also suggests that conformational switching may modulate the assembly of CD81-partner protein networks. This work furthers our understanding of the molecular mechanism of CD81 cholesterol sensing, how this relates to HCV entry, and CD81's function as a molecular scaffold; these insights are relevant to CD81's varied roles in both health and disease.
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Affiliation(s)
- Machaela Palor
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College, London, United Kingdom
| | - Lenka Stejskal
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College, London, United Kingdom; Institute of Structural and Molecular Biology, Birkbeck College, London, United Kingdom
| | - Piya Mandal
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College, London, United Kingdom
| | - Annasara Lenman
- Department of Clinical Microbiology, Virology & Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden; Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - María Pía Alberione
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Jared Kirui
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Rebecca Moeller
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Stefan Ebner
- Experimental Systems Immunology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Felix Meissner
- Experimental Systems Immunology, Max Planck Institute of Biochemistry, Martinsried, Germany; Institute of Innate Immunity, Department of Systems Immunology and Proteomics, Medical Faculty, University of Bonn, Bonn, Germany
| | - Gisa Gerold
- Department of Clinical Microbiology, Virology & Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden; Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany; Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Adrian J Shepherd
- Institute of Structural and Molecular Biology, Birkbeck College, London, United Kingdom
| | - Joe Grove
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College, London, United Kingdom.
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6
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Abstract
A critical step in the life cycle of a virus is spread to a new target cell, which generally involves the release of new viral particles from the infected cell which can then initiate infection in the next target cell. While cell-free viral particles released into the extracellular environment are necessary for long distance spread, there are disadvantages to this mechanism. These include the presence of immune system components, the low success rate of infection by single particles, and the relative fragility of viral particles in the environment. Several mechanisms of direct cell-to-cell spread have been reported for animal viruses which would avoid the issues associated with cell-free particles. A number of viruses can utilize several different mechanisms of direct cell-to-cell spread, but our understanding of the differential usage by these pathogens is modest. Although the mechanisms of cell-to-cell spread differ among viruses, there is a common exploitation of key pathways and components of the cellular cytoskeleton. Remarkably, some of the viral mechanisms of cell-to-cell spread are surprisingly similar to those used by bacteria. Here we summarize the current knowledge of the conventional and non-conventional mechanisms of viral spread, the common methods used to detect viral spread, and the impact that these mechanisms can have on viral pathogenesis.
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Affiliation(s)
- Nicolas Cifuentes-Munoz
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, San Miguel, Santiago, Chile
| | - Farah El Najjar
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Rebecca Ellis Dutch
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, United States.
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7
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Geng Y, Xu J. Stability and bifurcation analysis for a delayed viral infection model with full logistic proliferation. INT J BIOMATH 2020. [DOI: 10.1142/s1793524520500333] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper, we study a delayed viral infection model with cellular infection and full logistic proliferations for both healthy and infected cells. The global asymptotic stabilities of the equilibria are studied by constructing Lyapunov functionals. Moreover, we investigated the existence of Hopf bifurcation at the infected equilibrium by regarding the possible combination of the two delays as bifurcation parameters. The results show that time delays may destabilize the infected equilibrium and lead to Hopf bifurcation. Finally, numerical simulations are carried out to illustrate the main results and explore the dynamics including Hopf bifurcation and stability switches.
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Affiliation(s)
- Yan Geng
- School of Science, Xi’an Polytechnic University, Xi’an 710048, Shaanxi, P. R. China
| | - Jinhu Xu
- School of Sciences, Xi’an University of Technology, Xi’an 710049, Shaanxi, P. R. China
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8
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Abstract
Antiviral drugs have traditionally been developed by directly targeting essential viral components. However, this strategy often fails due to the rapid generation of drug-resistant viruses. Recent genome-wide approaches, such as those employing small interfering RNA (siRNA) or clustered regularly interspaced short palindromic repeats (CRISPR) or those using small molecule chemical inhibitors targeting the cellular "kinome," have been used successfully to identify cellular factors that can support virus replication. Since some of these cellular factors are critical for virus replication, but are dispensable for the host, they can serve as novel targets for antiviral drug development. In addition, potentiation of immune responses, regulation of cytokine storms, and modulation of epigenetic changes upon virus infections are also feasible approaches to control infections. Because it is less likely that viruses will mutate to replace missing cellular functions, the chance of generating drug-resistant mutants with host-targeted inhibitor approaches is minimized. However, drug resistance against some host-directed agents can, in fact, occur under certain circumstances, such as long-term selection pressure of a host-directed antiviral agent that can allow the virus the opportunity to adapt to use an alternate host factor or to alter its affinity toward the target that confers resistance. This review describes novel approaches for antiviral drug development with a focus on host-directed therapies and the potential mechanisms that may account for the acquisition of antiviral drug resistance against host-directed agents.
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9
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Reese H, Bordelon T, Odeh F, Broussard A, Kormos C, Murphy A, Shanahan C, Menegatti S. Purification of animal immunoglobulin G (IgG) using peptoid affinity ligands. Biotechnol Prog 2020; 36:e2994. [DOI: 10.1002/btpr.2994] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/07/2020] [Accepted: 03/02/2020] [Indexed: 01/19/2023]
Affiliation(s)
- Hannah Reese
- Department of Chemical and Biomolecular EngineeringNorth Carolina State University Raleigh North Carolina USA
| | | | - Fuad Odeh
- LigaTrap LLC Raleigh North Carolina USA
| | | | | | | | - Calvin Shanahan
- Department of Chemical and Biomolecular EngineeringNorth Carolina State University Raleigh North Carolina USA
| | - Stefano Menegatti
- Department of Chemical and Biomolecular EngineeringNorth Carolina State University Raleigh North Carolina USA
- Biomanufacturing Training and Education Center (BTEC)North Carolina State University Raleigh North Carolina USA
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10
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Mailly L, Baumert TF. Hepatitis C virus infection and tight junction proteins: The ties that bind. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183296. [PMID: 32268133 DOI: 10.1016/j.bbamem.2020.183296] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/25/2020] [Accepted: 03/28/2020] [Indexed: 02/07/2023]
Abstract
The hepatitis C virus (HCV) is a major cause of liver diseases ranging from liver inflammation to advanced liver diseases like cirrhosis and hepatocellular carcinoma (HCC). HCV infection is restricted to the liver, and more specifically to hepatocytes, which represent around 80% of liver cells. The mechanism of HCV entry in human hepatocytes has been extensively investigated since the discovery of the virus 30 years ago. The entry mechanism is a multi-step process relying on several host factors including heparan sulfate proteoglycan (HSPG), low density lipoprotein receptor (LDLR), tetraspanin CD81, Scavenger Receptor class B type I (SR-BI), Epidermal Growth Factor Receptor (EGFR) and Niemann-Pick C1-like 1 (NPC1L1). Moreover, in order to establish a persistent infection, HCV entry is dependent on the presence of tight junction (TJ) proteins Claudin-1 (CLDN1) and Occludin (OCLN). In the liver, tight junction proteins play a role in architecture and homeostasis including sealing the apical pole of adjacent cells to form bile canaliculi and separating the basolateral domain drained by sinusoidal blood flow. In this review, we will highlight the role of liver tight junction proteins in HCV infection, and we will discuss the potential targeted therapeutic approaches to improve virus eradication.
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Affiliation(s)
- Laurent Mailly
- Université de Strasbourg, INSERM, UMR-S1110, Institut de Recherche sur les Maladies Virales et Hépatiques, F-67000 Strasbourg, France.
| | - Thomas F Baumert
- Université de Strasbourg, INSERM, UMR-S1110, Institut de Recherche sur les Maladies Virales et Hépatiques, F-67000 Strasbourg, France; Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; Institut Universitaire de France, F-75231 Paris, France.
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11
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Hepatitis C Virus Entry: An Intriguingly Complex and Highly Regulated Process. Int J Mol Sci 2020; 21:ijms21062091. [PMID: 32197477 PMCID: PMC7140000 DOI: 10.3390/ijms21062091] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/15/2020] [Accepted: 03/16/2020] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) is a major cause of chronic hepatitis and liver disease worldwide. Its tissue and species tropism are largely defined by the viral entry process that is required for subsequent productive viral infection and establishment of chronic infection. This review provides an overview of the viral and host factors involved in HCV entry into hepatocytes, summarizes our understanding of the molecular mechanisms governing this process and highlights the therapeutic potential of host-targeting entry inhibitors.
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12
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Nelson B, Adams J, Kuglstatter A, Li Z, Harris SF, Liu Y, Bohini S, Ma H, Klumpp K, Gao J, Sidhu SS. Structure-Guided Combinatorial Engineering Facilitates Affinity and Specificity Optimization of Anti-CD81 Antibodies. J Mol Biol 2018; 430:2139-2152. [PMID: 29778602 DOI: 10.1016/j.jmb.2018.05.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/08/2018] [Accepted: 05/10/2018] [Indexed: 12/12/2022]
Abstract
Hepatitis C viral infection is the major cause of chronic hepatitis that affects as many as 71 million people worldwide. Rather than target the rapidly shifting viruses and their numerous serotypes, four independent antibodies were made to target the host antigen CD81 and were shown to block hepatitis C viral entry. The single-chain variable fragment of each antibody was crystallized in complex with the CD81 large extracellular loop in order to guide affinity maturation of two distinct antibodies by phage display. Affinity maturation of antibodies using phage display has proven to be critical to therapeutic antibody development and typically involves modification of the paratope for increased affinity, improved specificity, enhanced stability or a combination of these traits. One antibody was engineered for increased affinity for human CD81 large extracellular loop that equated to increased efficacy, while the second antibody was engineered for cross-reactivity with cynomolgus CD81 to facilitate animal model testing. The use of structures to guide affinity maturation library design demonstrates the utility of combining structural analysis with phage display technologies.
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Affiliation(s)
- Bryce Nelson
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Jarrett Adams
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | | | - Zhijian Li
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | | | - Yang Liu
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | | | - Han Ma
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | - Klaus Klumpp
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | - Junjun Gao
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA.
| | - Sachdev S Sidhu
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada.
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13
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Hansen DT, Craciunescu FM, Fromme P, Johnston SA, Sykes KF. Generation of High-Specificity Antibodies against Membrane Proteins Using DNA-Gold Micronanoplexes for Gene Gun Immunization. ACTA ACUST UNITED AC 2018. [PMID: 29516482 DOI: 10.1002/cpps.50] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Membrane proteins are the molecular interface of the cell and its environs; however, studies of membrane proteins are highly technically challenging, mainly due to instability of the isolated protein. Towards the production of antibodies that recognize properly folded and stabilized forms of membrane protein antigen, we describe a DNA-based immunization method for mice that expresses the antigen in the membranes of dendritic cells, thus allowing direct presentation to the immune system. This genetic immunization approach employs a highly efficient method of biolistic delivery based on DNA-gold micronanoplexes, which are complexes of micron-sized gold particles that allow dermal penetration and nanometer-sized gold particles that provide a higher surface area for DNA binding than micron gold alone. In contrast to antibodies derived from immunizations with detergent-solubilized protein or with protein fragments, antibodies from genetic immunization are expected to have a high capacity for binding conformational epitopes and for modulating membrane protein activity. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Debra T Hansen
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona
| | - Felicia M Craciunescu
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona
| | - Petra Fromme
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona
| | - Stephen A Johnston
- Biodesign Center for Innovations in Medicine, Arizona State University, Tempe, Arizona
| | - Kathryn F Sykes
- Biodesign Center for Innovations in Medicine, Arizona State University, Tempe, Arizona.,Current address: HealthTell, Inc, Chandler, Arizona
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14
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Kong SY, Jiang YS, Wang Q, Lu JF, Xu D, Lu LQ. Detection methods of Cyprinid herpesvirus 2 infection in silver crucian carp (Carassius auratus gibelio) via a pORF72 monoclonal antibody. JOURNAL OF FISH DISEASES 2017; 40:1791-1798. [PMID: 28548685 DOI: 10.1111/jfd.12648] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/10/2017] [Accepted: 03/14/2017] [Indexed: 06/07/2023]
Abstract
Cyprinid herpesvirus 2 (CyHV-2) is the main pathogen responsible for causing haematopoietic necrosis disease in Carassius auratus gibelio. Although many nucleic acid-based diagnostic methods have been applied, no stable and sensitive immunological diagnostic approaches have been reported. In this study, to detect CyHV-2 in clinical samples using immunological methods, recombinant ORF72 protein (pORF72), encoded by the CyHV-2 ORF72 gene, was used as a capture antigen to identify blood and tissues infected with CyHV-2. First, ORF72 gene was amplified from the CyHV-2 genome and cloned into a PGEX-4t-3 expression vector to produce pORF72 in Escherichia coli. The purified pORF72 was used as an immunogen to prepare monoclonal antibodies. The Western blotting assays revealed that the monoclonal antibody could specifically identify the pORF72. Furthermore, an immunohistochemical protocol and a blood smear method were established to detect CyHV-2 in carps. The results indicate that the monoclonal antibody against pORF72 could be utilized as an effective detection tool for haematopoietic necrosis disease in Carassius auratus gibelio.
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Affiliation(s)
- S Y Kong
- National Pathogen Collection Center for Aquatic Animals, Key Laboratory of Aquatic Genetic Resources of Ministry of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Y S Jiang
- National Pathogen Collection Center for Aquatic Animals, Key Laboratory of Aquatic Genetic Resources of Ministry of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Q Wang
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - J F Lu
- National Pathogen Collection Center for Aquatic Animals, Key Laboratory of Aquatic Genetic Resources of Ministry of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - D Xu
- National Pathogen Collection Center for Aquatic Animals, Key Laboratory of Aquatic Genetic Resources of Ministry of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - L Q Lu
- National Pathogen Collection Center for Aquatic Animals, Key Laboratory of Aquatic Genetic Resources of Ministry of Aquaculture, Shanghai Ocean University, Shanghai, China
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15
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Grove J, Hu K, Farquhar MJ, Goodall M, Walker L, Jamshad M, Drummer HE, Bill RM, Balfe P, McKeating JA. A new panel of epitope mapped monoclonal antibodies recognising the prototypical tetraspanin CD81. Wellcome Open Res 2017; 2:82. [PMID: 29090272 PMCID: PMC5657224 DOI: 10.12688/wellcomeopenres.12058.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2017] [Indexed: 12/26/2022] Open
Abstract
Background: Tetraspanins are small transmembrane proteins, found in all higher eukaryotes, that compartmentalize cellular membranes through interactions with partner proteins. CD81 is a prototypical tetraspanin and contributes to numerous physiological and pathological processes, including acting as a critical entry receptor for hepatitis C virus (HCV). Antibody engagement of tetraspanins can induce a variety of effects, including actin cytoskeletal rearrangements, activation of MAPK-ERK signaling and cell migration. However, the epitope specificity of most anti-tetraspanin antibodies is not known, limiting mechanistic interpretation of these studies. Methods: We generated a panel of monoclonal antibodies (mAbs) specific for CD81 second extracellular domain (EC2) and performed detailed epitope mapping with a panel of CD81 mutants. All mAbs were screened for their ability to inhibit HCV infection and E2-CD81 association. Nanoscale distribution of cell surface CD81 was investigated by scanning electron microscopy. Results: The antibodies were classified in two epitope groups targeting opposing sides of EC2. We observed a wide range of anti-HCV potencies that were independent of their epitope grouping, but associated with their relative affinity for cell-surface expressed CD81. Scanning electron microscopy identified at least two populations of CD81; monodisperse and higher-order assemblies, consistent with tetraspanin-enriched microdomains. Conclusions: These novel antibodies provide well-characterised tools to investigate CD81 function, including HCV entry, and have the potential to provide insights into tetraspanin biology in general.
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Affiliation(s)
- Joe Grove
- Institute of Immunity and Transplantation, Division of Infection and Immunity, , University College London, London, NW3 2PF, UK
| | - Ke Hu
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Michelle J. Farquhar
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Margaret Goodall
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Lucas Walker
- Institute of Immunity and Transplantation, Division of Infection and Immunity, , University College London, London, NW3 2PF, UK
| | - Mohammed Jamshad
- Institute for Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Heidi E. Drummer
- Centre for Biomedical Resear, Burnet Institute, Melbourne, VIC, 3004, Australia
| | - Roslyn M. Bill
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - Peter Balfe
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Jane A. McKeating
- Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7BN, UK
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Attachment and Postattachment Receptors Important for Hepatitis C Virus Infection and Cell-to-Cell Transmission. J Virol 2017; 91:JVI.00280-17. [PMID: 28404852 DOI: 10.1128/jvi.00280-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/10/2017] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) requires multiple receptors for its attachment to and entry into cells. Our previous studies found that human syndecan-1 (SDC-1), SDC-2, and T cell immunoglobulin and mucin domain-containing protein 1 (TIM-1) are HCV attachment receptors. Other cell surface molecules, such as CD81, Claudin-1 (CLDN1), Occludin (OCLN), SR-BI, and low-density lipoprotein receptor (LDLR), function mainly at postattachment steps and are considered postattachment receptors. The underlying molecular mechanisms of different receptors in HCV cell-free and cell-to-cell transmission remain elusive. In the present study, we used a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 technology, gene-specific small interfering RNAs, and a newly developed luciferase-based reporter system to quantitatively determine the importance of individual receptors in HCV cell-free and cell-to-cell transmission. Knockouts of SDC-1 and SDC-2 resulted in remarkable reductions of HCV infection and cell attachment, whereas SDC-3 and SDC-4 knockouts did not affect HCV infection. Defective HCV attachment to SDC-1 and/or SDC-2 knockout cells was completely restored by SDC-1 and SDC-2 but not SDC-4 expression. Knockout of the attachment receptors SDC-1, SDC-2, and TIM-1 also modestly decreased HCV cell-to-cell transmission. In contrast, silencing and knockout of the postattachment receptors CD81, CLDN1, OCLN, SR-BI, and LDLR greatly impaired both HCV cell-free and cell-to-cell transmission. Additionally, apolipoprotein E was found to be important for HCV cell-to-cell spread, but very-low-density lipoprotein (VLDL)-containing mouse serum did not affect HCV cell-to-cell transmission, although it inhibited cell-free infection. These findings demonstrate that attachment receptors are essential for initial HCV binding and that postattachment receptors are important for both HCV cell-free and cell-to-cell transmission.IMPORTANCE The importance and underlying molecular mechanisms of cell surface receptors in HCV cell-free and cell-to-cell transmission are poorly understood. The role of some of the HCV attachment and postattachment receptors in HCV infection and cell-to-cell spread remains controversial. Using CRISPR-Cas9-mediated knockouts of specific cellular genes, we demonstrate that both SDC-1 and SDC-2, but not SDC-3 or SDC-4, are bona fide HCV attachment receptors. We also used a newly developed luciferase-based reporter system to quantitatively determine the importance of attachment and postattachment receptors in HCV cell-to-cell transmission. SDC-1, SDC-2, TIM-1, and SR-BI were found to modestly promote HCV cell-to-cell spread. CD81, CLDN1, OCLN, and LDLR play more important roles in HCV cell-to-cell transmission. Likewise, apolipoprotein E (apoE) is critically important for HCV cell-to-cell spread, unlike VLDL-containing mouse serum, which did not affect HCV cell-to-cell spread. These findings suggest that the mechanism(s) of HCV cell-to-cell spread differs from that of cell-free infection.
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17
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Hammerstad SS, Stefan M, Blackard J, Owen RP, Lee HJ, Concepcion E, Yi Z, Zhang W, Tomer Y. Hepatitis C Virus E2 Protein Induces Upregulation of IL-8 Pathways and Production of Heat Shock Proteins in Human Thyroid Cells. J Clin Endocrinol Metab 2017; 102:689-697. [PMID: 27860532 PMCID: PMC5413166 DOI: 10.1210/jc.2016-3403] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 11/17/2016] [Indexed: 12/17/2022]
Abstract
CONTEXT Thyroiditis is one of the most common extrahepatic manifestations of hepatitis C virus (HCV) infection. By binding to surface cell receptor CD81, HCV envelope glycoprotein E2 mediates entry of HCV into cells. Studies have shown that different viral proteins may individually induce host responses to infection. We hypothesized that HCV E2 protein binding to CD81 expressed on thyroid cells activates a cascade of inflammatory responses that can trigger autoimmune thyroiditis in susceptible individuals. SETTING Human thyroid cell lines ML-1 and human thyrocytes in primary cell culture were treated with HCV recombinant E2 protein. The expression of major proinflammatory cytokines was measured at the messenger RNA and protein levels. Next-generation transcriptome analysis was used to identify early changes in gene expression in thyroid cells induced by E2. RESULTS HCV envelope protein E2 induced strong inflammatory responses in human thyrocytes, resulting in production of interleukin (IL)-8, IL-6, and tumor necrosis factor-α. Furthermore, the E2 protein induced production of several heat shock proteins including HSP60, HSP70p12A, and HSP10, in human primary thyrocytes. In thyroid cell line ML-1, RNA sequencing identified upregulation of molecules involved in innate immune pathways with high levels of proinflammatory cytokines and chemokines and increased expression of costimulatory molecules, specifically CD40, known to be a major thyroid autoimmunity gene. CONCLUSION Our data support a key role for HCV envelope protein E2 in triggering thyroid autoimmunity through activation of cytokine pathways by bystander mechanisms.
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Affiliation(s)
- Sara Salehi Hammerstad
- Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Aker, 0586 Oslo, Norway;
- Department of Pediatrics, Oslo University Hospital, Ullevål, 0450 Oslo, Norway;
| | - Mihaela Stefan
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York 10461;
| | - Jason Blackard
- Division of Digestive Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267;
| | | | - Hanna J. Lee
- Department of Medicine, Division of Endocrinology, and
| | - Erlinda Concepcion
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York 10461;
| | - Zhengzi Yi
- Department of Medicine Bioinformatics Core, Mount Sinai Hospital, Icahn School of Medicine, New York, New York 10029
| | - Weijia Zhang
- Department of Medicine Bioinformatics Core, Mount Sinai Hospital, Icahn School of Medicine, New York, New York 10029
| | - Yaron Tomer
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York 10461;
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18
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Chiang AWT, Wu WYL, Wang T, Hwang MJ. Identification of Entry Factors Involved in Hepatitis C Virus Infection Based on Host-Mimicking Short Linear Motifs. PLoS Comput Biol 2017; 13:e1005368. [PMID: 28129350 PMCID: PMC5302801 DOI: 10.1371/journal.pcbi.1005368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 02/10/2017] [Accepted: 01/17/2017] [Indexed: 12/15/2022] Open
Abstract
Host factors that facilitate viral entry into cells can, in principle, be identified from a virus-host protein interaction network, but for most viruses information for such a network is limited. To help fill this void, we developed a bioinformatics approach and applied it to hepatitis C virus (HCV) infection, which is a current concern for global health. Using this approach, we identified short linear sequence motifs, conserved in the envelope proteins of HCV (E1/E2), that potentially can bind human proteins present on the surface of hepatocytes so as to construct an HCV (envelope)-host protein interaction network. Gene Ontology functional and KEGG pathway analyses showed that the identified host proteins are enriched in cell entry and carcinogenesis functionalities. The validity of our results is supported by much published experimental data. Our general approach should be useful when developing antiviral agents, particularly those that target virus-host interactions. Viruses recruit host proteins, called entry factors, to help gain entry to host cells. Identification of entry factors can provide targets for developing antiviral drugs. By exploring the concept that short linear peptide motifs involved in human protein-protein interactions may be mimicked by viruses to hijack certain host cellular processes and thereby assist viral infection/survival, we developed a bioinformatics strategy to computationally identify entry factors of hepatitis C virus (HCV) infection, which is a worldwide health problem. Analysis of cellular functions and biochemical pathways indicated that the human proteins we identified usually play a role in cell entry and/or carcinogenesis, and results of the analysis are generally supported by experimental studies on HCV infection, including the ~80% (15 of 19) prediction rate of known HCV hepatocyte entry factors. Because molecular mimicry is a general concept, our bioinformatics strategy is a timely approach to identify new targets for antiviral research, not only for HCV but also for other viruses.
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Affiliation(s)
| | - Walt Y. L. Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ting Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ming-Jing Hwang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- * E-mail:
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19
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Global mapping of antibody recognition of the hepatitis C virus E2 glycoprotein: Implications for vaccine design. Proc Natl Acad Sci U S A 2016; 113:E6946-E6954. [PMID: 27791171 DOI: 10.1073/pnas.1614942113] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The E2 envelope glycoprotein is the primary target of human neutralizing antibody response against hepatitis C virus (HCV), and is thus a major focus of vaccine and immunotherapeutics efforts. There is emerging evidence that E2 is a highly complex, dynamic protein with residues across the protein that are modulating antibody recognition, local and global E2 stability, and viral escape. To comprehensively map these determinants, we performed global E2 alanine scanning with a panel of 16 human monoclonal antibodies (hmAbs), resulting in an unprecedented dataset of the effects of individual alanine substitutions across the E2 protein (355 positions) on antibody recognition. Analysis of shared energetic effects across the antibody panel identified networks of E2 residues involved in antibody recognition and local and global E2 stability, as well as predicted contacts between residues across the entire E2 protein. Further analysis of antibody binding hotspot residues defined groups of residues essential for E2 conformation and recognition for all 14 conformationally dependent E2 antibodies and subsets thereof, as well as residues that enhance antibody recognition when mutated to alanine, providing a potential route to engineer E2 vaccine immunogens. By incorporating E2 sequence variability, we found a number of E2 polymorphic sites that are responsible for loss of neutralizing antibody binding. These data and analyses provide fundamental insights into antibody recognition of E2, highlighting the dynamic and complex nature of this viral envelope glycoprotein, and can serve as a reference for development and rational design of E2-targeting vaccines and immunotherapeutics.
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20
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Mandal A, Ganta KK, Chaubey B. Combinations of siRNAs against La Autoantigen with NS5B or hVAP-A Have Additive Effect on Inhibition of HCV Replication. HEPATITIS RESEARCH AND TREATMENT 2016; 2016:9671031. [PMID: 27446609 PMCID: PMC4942654 DOI: 10.1155/2016/9671031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/23/2016] [Accepted: 05/30/2016] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus is major cause of chronic liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Presently available direct-acting antiviral drugs have improved success rate; however, high cost limits their utilization, especially in developing countries like India. In the present study, we evaluated anti-HCV potential of several siRNAs targeted against the HCV RNA-dependent RNA polymerase NS5B and cellular factors, La autoantigen, PSMA7, and human VAMP-associated protein to intercept different steps of viral life cycle. The target genes were downregulated individually as well as in combinations and their impact on viral replication was evaluated. Individual downregulation of La autoantigen, PSMA7, hVAP-A, and NS5B resulted in inhibition of HCV replication by about 67.2%, 50.7%, 39%, and 52%, respectively. However, antiviral effect was more pronounced when multiple genes were downregulated simultaneously. Combinations of siRNAs against La autoantigen with NS5B or hVAP-A resulted in greater inhibition in HCV replication. Our findings indicate that siRNA is a potential therapeutic tool for inhibiting HCV replication and simultaneously targeting multiple viral steps with the combination of siRNAs is more effective than silencing a single target.
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Affiliation(s)
- Anirban Mandal
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Krishna Kumar Ganta
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Binay Chaubey
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
- Laboratory of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, UG and MUG, Abrahama 58 Street, 80-307 Gdańsk, Poland
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21
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Hepatitis C virus depends on E-cadherin as an entry factor and regulates its expression in epithelial-to-mesenchymal transition. Proc Natl Acad Sci U S A 2016; 113:7620-5. [PMID: 27298373 DOI: 10.1073/pnas.1602701113] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) enters the host cell through interactions with a cascade of cellular factors. Although significant progress has been made in understanding HCV entry, the precise mechanisms by which HCV exploits the receptor complex and host machinery to enter the cell remain unclear. This intricate process of viral entry likely depends on additional yet-to-be-defined cellular molecules. Recently, by applying integrative functional genomics approaches, we identified and interrogated distinct sets of host dependencies in the complete HCV life cycle. Viral entry assays using HCV pseudoparticles (HCVpps) of various genotypes uncovered multiple previously unappreciated host factors, including E-cadherin, that mediate HCV entry. E-cadherin silencing significantly inhibited HCV infection in Huh7.5.1 cells, HepG2/miR122/CD81 cells, and primary human hepatocytes at a postbinding entry step. Knockdown of E-cadherin, however, had no effect on HCV RNA replication or internal ribosomal entry site (IRES)-mediated translation. In addition, an E-cadherin monoclonal antibody effectively blocked HCV entry and infection in hepatocytes. Mechanistic studies demonstrated that E-cadherin is closely associated with claudin-1 (CLDN1) and occludin (OCLN) on the cell membrane. Depletion of E-cadherin drastically diminished the cell-surface distribution of these two tight junction proteins in various hepatic cell lines, indicating that E-cadherin plays an important regulatory role in CLDN1/OCLN localization on the cell surface. Furthermore, loss of E-cadherin expression in hepatocytes is associated with HCV-induced epithelial-to-mesenchymal transition (EMT), providing an important link between HCV infection and liver cancer. Our data indicate that a dynamic interplay among E-cadherin, tight junctions, and EMT exists and mediates an important function in HCV entry.
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22
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Fauvelle C, Colpitts CC, Keck ZY, Pierce BG, Foung SKH, Baumert TF. Hepatitis C virus vaccine candidates inducing protective neutralizing antibodies. Expert Rev Vaccines 2016; 15:1535-1544. [PMID: 27267297 DOI: 10.1080/14760584.2016.1194759] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION With more than 150 million chronically infected people, hepatitis C virus (HCV) remains a substantial global health burden. Direct-acting antivirals have dramatically improved viral cure. However, limited access to therapy, late stage detection of infection and re-infection following cure illustrate the need for a vaccine for global control of infection. Vaccines with induction of neutralizing antibodies (nAbs) have been shown to protect successfully against infections by multiple viruses and are currently developed for HCV. Areas covered: Here we review the progress towards the development of vaccines aiming to confer protection against chronic HCV infection by inducing broadly nAbs. The understanding or viral immune evasion in infected patients, the development of novel model systems and the recent structural characterization of viral envelope glycoprotein E2 has markedly advanced our understanding of the molecular mechanisms of virus neutralization with the concomitant development of several vaccine candidates. Expert commentary: While HCV vaccine development remains challenged by the high viral diversity and immune evasion, marked progress in HCV research has advanced vaccine design. Several vaccine candidates have shown robust induction of nAbs in animal models and humans. Randomized clinical trials are the next step to assess their clinical efficacy for protection against chronic infection.
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Affiliation(s)
- Catherine Fauvelle
- a Inserm, U1110 , Institut de Recherche sur les Maladies Virales et Hépatiques , Strasbourg , France.,b Université de Strasbourg , Strasbourg , France
| | - Che C Colpitts
- a Inserm, U1110 , Institut de Recherche sur les Maladies Virales et Hépatiques , Strasbourg , France.,b Université de Strasbourg , Strasbourg , France
| | - Zhen-Yong Keck
- c Department of Pathology , Stanford University School of Medicine , Stanford , CA , USA
| | - Brian G Pierce
- d Institute for Bioscience and Biotechnology Research , University of Maryland , Rockville , MD , USA
| | - Steven K H Foung
- c Department of Pathology , Stanford University School of Medicine , Stanford , CA , USA
| | - Thomas F Baumert
- a Inserm, U1110 , Institut de Recherche sur les Maladies Virales et Hépatiques , Strasbourg , France.,b Université de Strasbourg , Strasbourg , France.,e Institut Hospitalo-Universitaire, Pôle Hépato-digestif , Hôpitaux Universitaires de Strasbourg , Strasbourg , France
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23
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Liu S, Wang S, Lu S. DNA immunization as a technology platform for monoclonal antibody induction. Emerg Microbes Infect 2016; 5:e33. [PMID: 27048742 PMCID: PMC4855071 DOI: 10.1038/emi.2016.27] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 12/06/2015] [Accepted: 12/15/2015] [Indexed: 01/17/2023]
Abstract
To combat the threat of many emerging infectious diseases, DNA immunization offers a unique and powerful approach to the production of high-quality monoclonal antibodies (mAbs) against various pathogens. Compared with traditional protein-based immunization approaches, DNA immunization is efficient for testing novel immunogen designs, does not require the production or purification of proteins from a pathogen or the use of recombinant protein technology and is effective at generating mAbs against conformation-sensitive targets. Although significant progress in the use of DNA immunization to generate mAbs has been made over the last two decades, the literature does not contain an updated summary of this experience. The current review provides a comprehensive analysis of the literature, including our own work, describing the use of DNA immunization to produce highly functional mAbs, in particular, those against emerging infectious diseases. Critical factors such as immunogen design, delivery approach, immunization schedule, use of immune modulators and the role of final boost immunization are discussed in detail.
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Affiliation(s)
| | - Shixia Wang
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Shan Lu
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
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24
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Polyclonal Antibody Production for Membrane Proteins via Genetic Immunization. Sci Rep 2016; 6:21925. [PMID: 26908053 PMCID: PMC4764931 DOI: 10.1038/srep21925] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 02/02/2016] [Indexed: 01/08/2023] Open
Abstract
Antibodies are essential for structural determinations and functional studies of membrane proteins, but antibody generation is limited by the availability of properly-folded and purified antigen. We describe the first application of genetic immunization to a structurally diverse set of membrane proteins to show that immunization of mice with DNA alone produced antibodies against 71% (n = 17) of the bacterial and viral targets. Antibody production correlated with prior reports of target immunogenicity in host organisms, underscoring the efficiency of this DNA-gold micronanoplex approach. To generate each antigen for antibody characterization, we also developed a simple in vitro membrane protein expression and capture method. Antibody specificity was demonstrated upon identifying, for the first time, membrane-directed heterologous expression of the native sequences of the FopA and FTT1525 virulence determinants from the select agent Francisella tularensis SCHU S4. These approaches will accelerate future structural and functional investigations of therapeutically-relevant membrane proteins.
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25
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Fauvelle C, Felmlee DJ, Crouchet E, Lee J, Heydmann L, Lefèvre M, Magri A, Hiet MS, Fofana I, Habersetzer F, Foung SKH, Milne R, Patel AH, Vercauteren K, Meuleman P, Zeisel MB, Bartenschlager R, Schuster C, Baumert TF. Apolipoprotein E Mediates Evasion From Hepatitis C Virus Neutralizing Antibodies. Gastroenterology 2016; 150:206-217.e4. [PMID: 26404951 DOI: 10.1053/j.gastro.2015.09.014] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 08/06/2015] [Accepted: 09/11/2015] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Efforts to develop an effective vaccine against hepatitis C virus (HCV) have been hindered by the propensity of the virus to evade host immune responses. HCV particles in serum and in cell culture associate with lipoproteins, which contribute to viral entry. Lipoprotein association has also been proposed to mediate viral evasion of the humoral immune response, though the mechanisms are poorly defined. METHODS We used small interfering RNAs to reduce levels of apolipoprotein E (apoE) in cell culture-derived HCV-producing Huh7.5-derived hepatoma cells and confirmed its depletion by immunoblot analyses of purified viral particles. Before infection of naïve hepatoma cells, we exposed cell culture-derived HCV strains of different genotypes, subtypes, and variants to serum and polyclonal and monoclonal antibodies isolated from patients with chronic HCV infection. We analyzed the interaction of apoE with viral envelope glycoprotein E2 and HCV virions by immunoprecipitation. RESULTS Through loss-of-function studies on patient-derived HCV variants of several genotypes and subtypes, we found that the HCV particle apoE allows the virus to avoid neutralization by patient-derived antibodies. Functional studies with human monoclonal antiviral antibodies showed that conformational epitopes of envelope glycoprotein E2 domains B and C were exposed after depletion of apoE. The level and conformation of virion-associated apoE affected the ability of the virus to escape neutralization by antibodies. CONCLUSIONS In cell-infection studies, we found that HCV-associated apoE helps the virus avoid neutralization by antibodies against HCV isolated from chronically infected patients. This method of immune evasion poses a challenge for the development of HCV vaccines.
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Affiliation(s)
- Catherine Fauvelle
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Daniel J Felmlee
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France; University of Plymouth, Centre for Biomedical Research, Plymouth, UK
| | - Emilie Crouchet
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - JiYoung Lee
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Laura Heydmann
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Mathieu Lefèvre
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Andrea Magri
- MRC, University of Glasgow, Centre for Virus Research, Glasgow, UK
| | - Marie-Sophie Hiet
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Isabel Fofana
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - François Habersetzer
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Steven K H Foung
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Ross Milne
- Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Arvind H Patel
- MRC, University of Glasgow, Centre for Virus Research, Glasgow, UK
| | - Koen Vercauteren
- Center for Vaccinology, Ghent University, Ghent University Hospital, Ghent, Belgium
| | - Philip Meuleman
- Center for Vaccinology, Ghent University, Ghent University Hospital, Ghent, Belgium
| | - Mirjam B Zeisel
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Catherine Schuster
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Thomas F Baumert
- Inserm, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
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Host-Targeting Agents to Prevent and Cure Hepatitis C Virus Infection. Viruses 2015; 7:5659-85. [PMID: 26540069 PMCID: PMC4664971 DOI: 10.3390/v7112898] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 09/25/2015] [Accepted: 10/19/2015] [Indexed: 12/13/2022] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma (HCC) which are leading indications of liver transplantation (LT). To date, there is no vaccine to prevent HCV infection and LT is invariably followed by infection of the liver graft. Within the past years, direct-acting antivirals (DAAs) have had a major impact on the management of chronic hepatitis C, which has become a curable disease in the majority of DAA-treated patients. In contrast to DAAs that target viral proteins, host-targeting agents (HTAs) interfere with cellular factors involved in the viral life cycle. By acting through a complementary mechanism of action and by exhibiting a generally higher barrier to resistance, HTAs offer a prospective option to prevent and treat viral resistance. Indeed, given their complementary mechanism of action, HTAs and DAAs can act in a synergistic manner to reduce viral loads. This review summarizes the different classes of HTAs against HCV infection that are in preclinical or clinical development and highlights their potential to prevent HCV infection, e.g., following LT, and to tailor combination treatments to cure chronic HCV infection.
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Schweitzer CJ, Liang TJ. Border Control in Hepatitis C Virus Infection: Inhibiting Viral Entry. ACS Infect Dis 2015; 1:416-9. [PMID: 27617924 DOI: 10.1021/acsinfecdis.5b00060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A new era has begun in the treatment of hepatitis C virus (HCV) infection with powerful yet expensive therapies. New treatments are emerging that target the entry step of HCV and could potentially block reinfection after liver transplant. These treatments include antibodies, which target the virus or host receptors required by HCV. Additionally, several new and previously approved small-molecule compounds have been described that target unique aspects of HCV entry. Overall, the blocking entry represents an attractive strategy that could yield powerful combination therapies to combat HCV.
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Affiliation(s)
- Cameron J. Schweitzer
- Liver Diseases
Branch, National Institute of Diabetes and Digestive and Kidney Diseases
(NIDDK), National Institutes of Health (NIH), Bethesda, Maryland 20892, United States
| | - T. Jake Liang
- Liver Diseases
Branch, National Institute of Diabetes and Digestive and Kidney Diseases
(NIDDK), National Institutes of Health (NIH), Bethesda, Maryland 20892, United States
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28
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Tawar RG, Colpitts CC, Timm J, Fehm T, Roggendorf M, Meisel H, Meyer N, Habersetzer F, Cosset FL, Berg T, Zeisel MB, Baumert TF. Acute hepatitis C virus infection induces anti-host cell receptor antibodies with virus-neutralizing properties. Hepatology 2015; 62:726-36. [PMID: 26010076 DOI: 10.1002/hep.27906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 05/19/2015] [Indexed: 12/17/2022]
Abstract
UNLABELLED Hepatitis C virus (HCV) causes persistent infection in the majority of infected individuals. The mechanisms of persistence and clearance are only partially understood. Antibodies (Abs) against host cell entry receptors have been shown to inhibit HCV infection in cell culture and animal models. In this study, we aimed to investigate whether anti-receptor Abs are induced during infection in humans in vivo and whether their presence is associated with outcome of infection. We established an enzyme-linked immunosorbant assay using a recombinant CD81-claudin-1 (CLDN1) fusion protein to detect and quantify Abs directed against extracellular epitopes of the HCV CD81-CLDN1 coreceptor complex. The presence of anti-receptor Abs was studied in serum of patients from a well-defined cohort of a single-source HCV outbreak of pregnant women and several control groups, including uninfected pregnant women, patients with chronic hepatitis B and D virus (HBV/HDV) infection, and healthy individuals. Virus-neutralizing activity of Abs was determined using recombinant cell culture-derived HCV (HCVcc). Our results demonstrate that HCV-infected patients have statistically significantly higher anti-CD81/CLDN1 Ab titers during the early phase of infection than controls. The titers were significantly higher in resolvers compared to persisters. Functional studies using immunoadsorption and HCV cell culture models demonstrate that HCV-neutralizing anti-receptor Abs are induced in the early phase of HCV infection, but not in control groups. CONCLUSION The virus-neutralizing properties of these Abs suggest a role for control of viral infection in conjunction with antiviral responses. Characterization of these anti-receptor Abs opens new avenues to prevent and treat HCV infection.
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Affiliation(s)
- Rajiv G Tawar
- Inserm, U1110, Institut des Maladies Virales et Hépatiques, Strasbourg, France.,University of Strasbourg, Strasbourg, France
| | - Che C Colpitts
- Inserm, U1110, Institut des Maladies Virales et Hépatiques, Strasbourg, France.,University of Strasbourg, Strasbourg, France
| | - Jörg Timm
- Institute for Virology, University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
| | - Tanja Fehm
- Department of Gynecology and Obstetrics, University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
| | | | - Helga Meisel
- Institute of Medical Virology, Helmut-Ruska-Haus, Charité University Medicine, Berlin, Germany
| | - Nicolas Meyer
- Pôle de Santé Publique, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - François Habersetzer
- Inserm, U1110, Institut des Maladies Virales et Hépatiques, Strasbourg, France.,University of Strasbourg, Strasbourg, France.,Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - François-Loïc Cosset
- CIRI-International Center for Infectiology Research, Lyon, France; Inserm, U1111, Lyon France; Ecole Normale Supérieure; CNRS UMR 5308, Lyon, France; LabEx Ecofect, University of Lyon, Lyon, France
| | - Thomas Berg
- Department of Internal Medicine, Neurology and Dermatology, Gastroenterology and Rheumatology Clinic, Section of Hepatology, University of Leipzig, Leipzig, Germany
| | - Mirjam B Zeisel
- Inserm, U1110, Institut des Maladies Virales et Hépatiques, Strasbourg, France.,University of Strasbourg, Strasbourg, France
| | - Thomas F Baumert
- Inserm, U1110, Institut des Maladies Virales et Hépatiques, Strasbourg, France.,University of Strasbourg, Strasbourg, France.,Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
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29
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Tarr AW, Khera T, Hueging K, Sheldon J, Steinmann E, Pietschmann T, Brown RJP. Genetic Diversity Underlying the Envelope Glycoproteins of Hepatitis C Virus: Structural and Functional Consequences and the Implications for Vaccine Design. Viruses 2015; 7:3995-4046. [PMID: 26193307 PMCID: PMC4517138 DOI: 10.3390/v7072809] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/19/2015] [Accepted: 07/08/2015] [Indexed: 12/13/2022] Open
Abstract
In the 26 years since the discovery of Hepatitis C virus (HCV) a major global research effort has illuminated many aspects of the viral life cycle, facilitating the development of targeted antivirals. Recently, effective direct-acting antiviral (DAA) regimens with >90% cure rates have become available for treatment of chronic HCV infection in developed nations, representing a significant advance towards global eradication. However, the high cost of these treatments results in highly restricted access in developing nations, where the disease burden is greatest. Additionally, the largely asymptomatic nature of infection facilitates continued transmission in at risk groups and resource constrained settings due to limited surveillance. Consequently a prophylactic vaccine is much needed. The HCV envelope glycoproteins E1 and E2 are located on the surface of viral lipid envelope, facilitate viral entry and are the targets for host immunity, in addition to other functions. Unfortunately, the extreme global genetic and antigenic diversity exhibited by the HCV glycoproteins represents a significant obstacle to vaccine development. Here we review current knowledge of HCV envelope protein structure, integrating knowledge of genetic, antigenic and functional diversity to inform rational immunogen design.
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Affiliation(s)
- Alexander W Tarr
- School of Life Sciences, Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham NG7 2RD, UK.
| | - Tanvi Khera
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
| | - Kathrin Hueging
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
| | - Julie Sheldon
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
| | - Eike Steinmann
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
| | - Thomas Pietschmann
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
- German Centre for Infection Research (DZIF), partner site Hannover-Braunschweig, Braunschweig 38124, Germany.
| | - Richard J P Brown
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture between the Medical School Hannover (MHH) and the Helmholtz Centrefor Infection Research (HZI), Hannover D-30625, Germany.
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30
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Padmanabhan P, Dixit NM. Modeling Suggests a Mechanism of Synergy Between Hepatitis C Virus Entry Inhibitors and Drugs of Other Classes. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2015; 4:445-53. [PMID: 26380153 PMCID: PMC4562160 DOI: 10.1002/psp4.12005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/01/2015] [Accepted: 06/04/2015] [Indexed: 12/25/2022]
Abstract
Hepatitis C virus (HCV) entry inhibitors (EIs) act synergistically with drugs targeting other stages of the HCV lifecycle. The origin of this synergy remains unknown. Here, we argue that the synergy may arise from the complementary activities of the drugs across cell subpopulations expressing different levels of HCV entry receptors. We employ mathematical modeling of viral kinetics in vitro, where cells with a distribution of entry receptor expression levels are exposed to HCV with or without drugs. The drugs act independently in each cell, as expected in the absence of underlying interactions. Yet, at the cell population level our model predicts that the drugs exhibit synergy. EIs effectively block infection of cells with low receptor levels. With high receptor levels, where EIs are compromised, other drugs are potent. This novel mechanism of synergy, arising at the cell population level may facilitate interpretation of drug activity and treatment optimization.
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Affiliation(s)
- P Padmanabhan
- Department of Chemical Engineering, Indian Institute of Science Bangalore, Karnataka, India
| | - N M Dixit
- Department of Chemical Engineering, Indian Institute of Science Bangalore, Karnataka, India
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31
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Graw F, Martin DN, Perelson AS, Uprichard SL, Dahari H. Quantification of Hepatitis C Virus Cell-to-Cell Spread Using a Stochastic Modeling Approach. J Virol 2015; 89:6551-61. [PMID: 25833046 PMCID: PMC4468510 DOI: 10.1128/jvi.00016-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 03/24/2015] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED It has been proposed that viral cell-to-cell transmission plays a role in establishing and maintaining chronic infections. Thus, understanding the mechanisms and kinetics of cell-to-cell spread is fundamental to elucidating the dynamics of infection and may provide insight into factors that determine chronicity. Because hepatitis C virus (HCV) spreads from cell to cell and has a chronicity rate of up to 80% in exposed individuals, we examined the dynamics of HCV cell-to-cell spread in vitro and quantified the effect of inhibiting individual host factors. Using a multidisciplinary approach, we performed HCV spread assays and assessed the appropriateness of different stochastic models for describing HCV focus expansion. To evaluate the effect of blocking specific host cell factors on HCV cell-to-cell transmission, assays were performed in the presence of blocking antibodies and/or small-molecule inhibitors targeting different cellular HCV entry factors. In all experiments, HCV-positive cells were identified by immunohistochemical staining and the number of HCV-positive cells per focus was assessed to determine focus size. We found that HCV focus expansion can best be explained by mathematical models assuming focus size-dependent growth. Consistent with previous reports suggesting that some factors impact HCV cell-to-cell spread to different extents, modeling results estimate a hierarchy of efficacies for blocking HCV cell-to-cell spread when targeting different host factors (e.g., CLDN1 > NPC1L1 > TfR1). This approach can be adapted to describe focus expansion dynamics under a variety of experimental conditions as a means to quantify cell-to-cell transmission and assess the impact of cellular factors, viral factors, and antivirals. IMPORTANCE The ability of viruses to efficiently spread by direct cell-to-cell transmission is thought to play an important role in the establishment and maintenance of viral persistence. As such, elucidating the dynamics of cell-to-cell spread and quantifying the effect of blocking the factors involved has important implications for the design of potent antiviral strategies and controlling viral escape. Mathematical modeling has been widely used to understand HCV infection dynamics and treatment response; however, these models typically assume only cell-free virus infection mechanisms. Here, we used stochastic models describing focus expansion as a means to understand and quantify the dynamics of HCV cell-to-cell spread in vitro and determined the degree to which cell-to-cell spread is reduced when individual HCV entry factors are blocked. The results demonstrate the ability of this approach to recapitulate and quantify cell-to-cell transmission, as well as the impact of specific factors and potential antivirals.
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Affiliation(s)
- Frederik Graw
- Center for Modeling and Simulation in the Biosciences, BioQuant Center, Heidelberg University, Heidelberg, Germany
| | - Danyelle N Martin
- Program for Experimental and Theoretical Modeling, Division of Hepatology, Department of Medicine, Loyola University Medical Center, Maywood, Illinois, USA
| | - Alan S Perelson
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Susan L Uprichard
- Program for Experimental and Theoretical Modeling, Division of Hepatology, Department of Medicine, Loyola University Medical Center, Maywood, Illinois, USA Department of Microbiology and Immunology, Loyola University Medical Center, Maywood, Illinois, USA
| | - Harel Dahari
- Program for Experimental and Theoretical Modeling, Division of Hepatology, Department of Medicine, Loyola University Medical Center, Maywood, Illinois, USA Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
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32
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Drummer HE. Editorial on "Broadly neutralizing antibodies abrogate established hepatitis C virus infection" published in Science Translational Medicine on 17th September 2014. ANNALS OF TRANSLATIONAL MEDICINE 2015; 3:S6. [PMID: 26046093 DOI: 10.3978/j.issn.2305-5839.2015.03.55] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/06/2015] [Indexed: 11/14/2022]
Abstract
Hepatitis C virus (HCV) is a blood borne pathogen that causes chronic liver disease and afflicts 170 million people world-wide. While direct acting antivirals now provide a highly effective means to cure those infected with HCV, there is no vaccine to prevent infection. Published in Science Translational Medicine, de Jong et al. [2014] show that highly potent neutralizing antibodies (NAbs) directed to one of the surface glycoproteins of HCV, E2, can not only prevent infection but can also eliminate established infection in experimental animal models of HCV. They provide compelling evidence that for HCV to maintain a chronic infection, it must infect new hepatocytes; infection cannot be sustained in reservoirs of infected cells alone and that E2-specific NAbs are sufficient to cure an infection. In addition, the manuscript further supports the importance of NAbs in preventing, controlling and possibly curing HCV. Thus NAbs are not only essential to the development of prophylactic vaccines but may yet have a role in therapeutic approaches to HCV treatment.
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Affiliation(s)
- Heidi E Drummer
- Viral Fusion Laboratory, Centre for Biomedical Research, Burnet Institute, Melbourne, Australia
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33
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Ji C, Liu Y, Pamulapati C, Bohini S, Fertig G, Schraeml M, Rubas W, Brandt M, Ries S, Ma H, Klumpp K. Prevention of hepatitis C virus infection and spread in human liver chimeric mice by an anti-CD81 monoclonal antibody. Hepatology 2015; 61:1136-44. [PMID: 25417967 DOI: 10.1002/hep.27603] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 11/13/2014] [Indexed: 01/01/2023]
Abstract
UNLABELLED CD81 is a required receptor for hepatitis C virus (HCV) infection of human hepatocytes in vitro. We generated several high-affinity anti-human CD81 monoclonal antibodies (mAbs) that demonstrated potent, specific, and cross-genotype inhibition of HCV entry. One of these mAbs, K04, was administered to human liver chimeric mice before or after HCV infection to determine its ability to prevent HCV infection or spread of HCV infection, respectively. All vehicle control mice established HCV infection, reaching steady-state levels of serum HCV RNA by day 21. Pretreatment of mice with K04 prevented HCV infection in all mice (n = 5). Treatment of mice with mAb K04 every 3 days for 21 days, starting at 6 hours postinfection, resulted in effective inhibition of virus spread. In 3 mice that were sacrificed on day 24, serum HCV levels remained detectable, below the limit of quantification (LOQ), indicating that infection was established, but virus spread was blocked, by the anti-CD81 mAb. In 5 additional mice that were followed for a longer time, virus remained detectable, below LOQ, until days 24 and 30 in 4 of 5 mice. In the fifth mouse, viral load was quantifiable, but reduced to 64-fold below the mean viral load in vehicle control at day 24. In addition, 2 of 5 mice cleared the infection by day 30 and 1 mouse had undetectable virus load from day 6 onward. CONCLUSION These results demonstrate that CD81 is required for HCV infection and virus spread in vivo, and that anti-CD81 antibodies such as K04 may have potential as broad-spectrum antiviral agents for prevention and treatment of HCV infection.
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34
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Ren Q, Li C, Yuan P, Cai C, Zhang L, Luo GG, Wei W. A Dual-reporter system for real-time monitoring and high-throughput CRISPR/Cas9 library screening of the hepatitis C virus. Sci Rep 2015; 5:8865. [PMID: 25746010 PMCID: PMC4352851 DOI: 10.1038/srep08865] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/05/2015] [Indexed: 12/12/2022] Open
Abstract
The hepatitis C virus (HCV) is one of the leading causes of chronic hepatitis, liver cirrhosis and hepatocellular carcinomas and infects approximately 170 million people worldwide. Although several reporter systems have been developed, many shortcomings limit their use in the assessment of HCV infections. Here, we report a real-time live-cell reporter, termed the NIrD (NS3-4A Inducible rtTA-mediated Dual-reporter) system, which provides an on-off switch specifically in response to an HCV infection. Using the NIrD system and a focused CRISPR/Cas9 library, we identified CLDN1, OCLN and CD81 as essential genes for both the cell-free entry and the cell-to-cell transmission of HCV. The combination of this ultra-sensitive reporter system and the CRISPR knockout screening provides a powerful and high-throughput strategy for the identification of critical host components for HCV infections.
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Affiliation(s)
- Qingpeng Ren
- Biodynamic Optical Imaging Center (BIOPIC), Peking-Tsinghua Center for Life Sciences, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Chan Li
- Biodynamic Optical Imaging Center (BIOPIC), Peking-Tsinghua Center for Life Sciences, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Pengfei Yuan
- Biodynamic Optical Imaging Center (BIOPIC), Peking-Tsinghua Center for Life Sciences, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Changzu Cai
- Biodynamic Optical Imaging Center (BIOPIC), Peking-Tsinghua Center for Life Sciences, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Linqi Zhang
- Comprehensive AIDS Research Center and Research Center for Public Health, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Guangxiang George Luo
- Department of Microbiology, University of Alabama at Birmingham School of Medicine, Birmingham, Alabama 35294, USA
- Department of Microbiology, Peking University College of Basic Medical Sciences, Beijing 100083, China
| | - Wensheng Wei
- Biodynamic Optical Imaging Center (BIOPIC), Peking-Tsinghua Center for Life Sciences, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
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35
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Xiao F, Fofana I, Thumann C, Mailly L, Alles R, Robinet E, Meyer N, Schaeffer M, Habersetzer F, Doffoël M, Leyssen P, Neyts J, Zeisel MB, Baumert TF. Synergy of entry inhibitors with direct-acting antivirals uncovers novel combinations for prevention and treatment of hepatitis C. Gut 2015; 64:483-94. [PMID: 24848265 PMCID: PMC4345833 DOI: 10.1136/gutjnl-2013-306155] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Although direct-acting antiviral agents (DAAs) have markedly improved the outcome of treatment in chronic HCV infection, there continues to be an unmet medical need for improved therapies in difficult-to-treat patients as well as liver graft infection. Viral entry is a promising target for antiviral therapy. DESIGN Aiming to explore the role of entry inhibitors for future clinical development, we investigated the antiviral efficacy and toxicity of entry inhibitors in combination with DAAs or other host-targeting agents (HTAs). Screening a large series of combinations of entry inhibitors with DAAs or other HTAs, we uncovered novel combinations of antivirals for prevention and treatment of HCV infection. RESULTS Combinations of DAAs or HTAs and entry inhibitors including CD81-, scavenger receptor class B type I (SR-BI)- or claudin-1 (CLDN1)-specific antibodies or small-molecule inhibitors erlotinib and dasatinib were characterised by a marked and synergistic inhibition of HCV infection over a broad range of concentrations with undetectable toxicity in experimental designs for prevention and treatment both in cell culture models and in human liver-chimeric uPA/SCID mice. CONCLUSIONS Our results provide a rationale for the development of antiviral strategies combining entry inhibitors with DAAs or HTAs by taking advantage of synergy. The uncovered combinations provide perspectives for efficient strategies to prevent liver graft infection and novel interferon-free regimens.
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Affiliation(s)
- Fei Xiao
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Isabel Fofana
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Christine Thumann
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Laurent Mailly
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Roxane Alles
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France,Inserm, U977, Strasbourg, France
| | - Eric Robinet
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Nicolas Meyer
- Pôle de Santé Publique, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France
| | - Mickaël Schaeffer
- Pôle de Santé Publique, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France
| | - François Habersetzer
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France,Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Michel Doffoël
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France,Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Pieter Leyssen
- Rega Institute for Medical Research, KULeuven, Leuven, Belgium
| | - Johan Neyts
- Rega Institute for Medical Research, KULeuven, Leuven, Belgium
| | - Mirjam B Zeisel
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France
| | - Thomas F Baumert
- Inserm, U1110, Strasbourg, France,Université de Strasbourg, Strasbourg, France,Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France,Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, USA
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Hu SL, Liou CJ, Cheng YH, Yiu JC, Chiou PP, Lai YS. Development and characterization of two monoclonal antibodies against grouper iridovirus 55L and 97L proteins. JOURNAL OF FISH DISEASES 2015; 38:249-258. [PMID: 24476022 DOI: 10.1111/jfd.12230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/15/2013] [Accepted: 12/16/2013] [Indexed: 06/03/2023]
Abstract
Grouper iridovirus (GIV) is one of the most important viral pathogens in grouper, particularly at the fry and fingerling stages. The study of GIV pathogenicity has been hampered by the lack of proper immunological reagents to study the expression and function of viral proteins in the infected cells. In this study, two mouse monoclonal antibodies (mAbs) against GIV 55L and 97L proteins were produced. Enzyme-linked immunosorbent assay (ELISA) and Western blotting were used to screen these hybridomas, resulting in the identification of two high-affinity mAbs named GIV55L-mAb-2 and GIV97L-mAb-3, respectively. Both mAbs belong to the IgG1 isotype and were effective in detecting their respective target viral protein. Reverse-transcription polymerase chain reaction (RT-PCR) and Western blot analyses of GIV-infected GK cells revealed that GIV 97L is an immediate early gene, whereas GIV 55L a late one. The localization of 55L and 97L in GIV-infected cells was further characterized by immunofluorescence microscopy with the mAbs. The 55L protein mainly aggregated in the cytoplasm while 97L distributed in both the nucleus and cytoplasm of the infected cells. These studies demonstrate the validity of the two mAbs as immunodiagnostic and research reagents.
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Affiliation(s)
- S-L Hu
- Department of Biotechnology and Animal Science, National Ilan University, Yilan, Taiwan
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37
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Al Olaby RR, Cocquerel L, Zemla A, Saas L, Dubuisson J, Vielmetter J, Marcotrigiano J, Khan AG, Catalan FV, Perryman AL, Freundlich JS, Forli S, Levy S, Balhorn R, Azzazy HM. Identification of a novel drug lead that inhibits HCV infection and cell-to-cell transmission by targeting the HCV E2 glycoprotein. PLoS One 2014; 9:e111333. [PMID: 25357246 PMCID: PMC4214736 DOI: 10.1371/journal.pone.0111333] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 09/23/2014] [Indexed: 12/17/2022] Open
Abstract
Hepatitis C Virus (HCV) infects 200 million individuals worldwide. Although several FDA approved drugs targeting the HCV serine protease and polymerase have shown promising results, there is a need for better drugs that are effective in treating a broader range of HCV genotypes and subtypes without being used in combination with interferon and/or ribavirin. Recently, two crystal structures of the core of the HCV E2 protein (E2c) have been determined, providing structural information that can now be used to target the E2 protein and develop drugs that disrupt the early stages of HCV infection by blocking E2’s interaction with different host factors. Using the E2c structure as a template, we have created a structural model of the E2 protein core (residues 421–645) that contains the three amino acid segments that are not present in either structure. Computational docking of a diverse library of 1,715 small molecules to this model led to the identification of a set of 34 ligands predicted to bind near conserved amino acid residues involved in the HCV E2: CD81 interaction. Surface plasmon resonance detection was used to screen the ligand set for binding to recombinant E2 protein, and the best binders were subsequently tested to identify compounds that inhibit the infection of Huh-7 cells by HCV. One compound, 281816, blocked E2 binding to CD81 and inhibited HCV infection in a genotype-independent manner with IC50’s ranging from 2.2 µM to 4.6 µM. 281816 blocked the early and late steps of cell-free HCV entry and also abrogated the cell-to-cell transmission of HCV. Collectively the results obtained with this new structural model of E2c suggest the development of small molecule inhibitors such as 281816 that target E2 and disrupt its interaction with CD81 may provide a new paradigm for HCV treatment.
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Affiliation(s)
- Reem R. Al Olaby
- Department of Chemistry, The American University in Cairo, New Cairo, Egypt
| | - Laurence Cocquerel
- Center for Infection and Immunity of Lille, CNRS-UMR8204/Inserm-U1019, Pasteur Institute of Lille, University of Lille North of France, Lille, France
| | - Adam Zemla
- Pathogen Bioinformatics, Lawrence Livermore National Laboratory, Livermore, CA, United States of America
| | - Laure Saas
- Center for Infection and Immunity of Lille, CNRS-UMR8204/Inserm-U1019, Pasteur Institute of Lille, University of Lille North of France, Lille, France
| | - Jean Dubuisson
- Center for Infection and Immunity of Lille, CNRS-UMR8204/Inserm-U1019, Pasteur Institute of Lille, University of Lille North of France, Lille, France
| | - Jost Vielmetter
- Protein Expression Center, Beckman Institute, California Institute of Technology, Pasadena, CA, United States of America
| | - Joseph Marcotrigiano
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, United States of America
| | - Abdul Ghafoor Khan
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, United States of America
| | - Felipe Vences Catalan
- Department of Medicine, Stanford University Medical Center, Stanford, CA, United States of America
| | - Alexander L. Perryman
- Department of Medicine, Division of Infectious Diseases, Center for Emerging & Re-emerging Pathogens, Rutgers University-New Jersey Medical School, Newark, NJ, United States of America
| | - Joel S. Freundlich
- Department of Medicine, Division of Infectious Diseases, Center for Emerging & Re-emerging Pathogens, Rutgers University-New Jersey Medical School, Newark, NJ, United States of America
- Department of Pharmacology and Physiology, Rutgers University-New Jersey Medical School, Newark, NJ, United States of America
| | - Stefano Forli
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States of America
| | - Shoshana Levy
- Department of Medicine, Stanford University Medical Center, Stanford, CA, United States of America
| | - Rod Balhorn
- Department of Applied Science, University of California Davis, Davis, CA, United States of America
- * E-mail:
| | - Hassan M. Azzazy
- Department of Chemistry, The American University in Cairo, New Cairo, Egypt
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Development and application of a monoclonal antibody against grouper iridovirus (GIV) major capsid protein. J Virol Methods 2014; 205:31-7. [DOI: 10.1016/j.jviromet.2014.04.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 04/10/2014] [Accepted: 04/16/2014] [Indexed: 12/27/2022]
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Xiao F, Fofana I, Heydmann L, Barth H, Soulier E, Habersetzer F, Doffoël M, Bukh J, Patel AH, Zeisel MB, Baumert TF. Hepatitis C virus cell-cell transmission and resistance to direct-acting antiviral agents. PLoS Pathog 2014; 10:e1004128. [PMID: 24830295 PMCID: PMC4022730 DOI: 10.1371/journal.ppat.1004128] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 04/02/2014] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs) in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs. In spite of the rapid development of antiviral agents, antiviral resistance remains a challenge for the treatment of viral infections including hepatitis B and C virus (HBV, HCV), human immunodeficiency virus (HIV) and influenza. Virus spreads from infected cells to surrounding uninfected host cells to develop infection through cell-free and cell-cell transmission routes. Understanding the spread of resistant virus is important for the development of novel antiviral strategies to prevent and treat antiviral resistance. Here, we characterize the spread of resistant viruses and its impact for emergence and prevention of resistance using HCV as a model system. Our results show that cell-cell transmission is the main transmission route for antiviral resistant HCV strains and is crucial for the maintenance of infection. Monoclonal antibodies or small molecules targeting HCV entry factors are effective in inhibiting the spread of resistant HCV in cell culture models and thus should be evaluated clinically for prevention and treatment of HCV resistance. Combination of inhibitors targeting viral entry and clinically used direct-acting antivirals (DAAs) prevents antiviral resistance and leads to viral eradication in cell culture models. Collectively, the investigation provides a new strategy for prevention of viral resistance to antiviral agents.
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Affiliation(s)
- Fei Xiao
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Isabel Fofana
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Laura Heydmann
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Heidi Barth
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- Laboratoire de Virologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Eric Soulier
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - François Habersetzer
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Michel Doffoël
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital and Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Arvind H. Patel
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Mirjam B. Zeisel
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Thomas F. Baumert
- Inserm, U1110, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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CD81-receptor associations--impact for hepatitis C virus entry and antiviral therapies. Viruses 2014; 6:875-92. [PMID: 24553110 PMCID: PMC3939486 DOI: 10.3390/v6020875] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/12/2014] [Accepted: 02/13/2014] [Indexed: 02/07/2023] Open
Abstract
Tetraspanins are integral transmembrane proteins organized in microdomains displaying specific and direct interactions with other tetraspanins and molecular partners. Among them, CD81 has been implicated in a variety of physiological and pathological processes. CD81 also plays a crucial role in pathogen entry into host cells, including hepatitis C virus (HCV) entry into hepatocytes. HCV is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV entry into hepatocytes is a complex process that requires the coordinated interaction of viral and host factors for the initiation of infection, including CD81, scavenger receptor BI, claudin-1, occludin, membrane-bound host cell kinases, Niemann-Pick C1 Like 1, Harvey rat sarcoma viral oncogene homolog (HRas), CD63 and transferrin receptor 1. Furthermore, recent data in HCV model systems have demonstrated that targeting critical components of tetraspanins and associated cell membrane proteins open new avenues to prevent and treat viral infection.
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Fofana I, Jilg N, Chung RT, Baumert TF. Entry inhibitors and future treatment of hepatitis C. Antiviral Res 2014; 104:136-42. [PMID: 24525381 DOI: 10.1016/j.antiviral.2014.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 01/29/2014] [Accepted: 02/02/2014] [Indexed: 12/25/2022]
Abstract
Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma. Furthermore, HCV-induced liver disease is the leading indication for liver transplantation. The recent introduction of direct-acting antivirals (DAAs) has revolutionized HCV treatment by making possible the cure of the majority of patients. However, their efficacy and safety in difficult-to-treat patients such as patients receiving immunosuppression, those with advanced liver disease, co-morbidity and HIV/HCV-co-infection remain to be determined. Furthermore, prevention of liver graft infection remains a pressing issue. HCV entry inhibitors target the very first step of the HCV life cycle and efficiently inhibit cell-cell transmission - a key prerequisite for viral spread. Because of their unique mechanism of action on cell-cell transmission they may provide a promising and simple perspective for prevention of liver graft infection. A high genetic barrier to resistance and complementary mechanism of action compared to DAAs makes entry inhibitors attractive as a new strategy for treatment of multi-resistant or difficult-to-treat patients. Clinical studies are needed to determine the future role of entry inhibitors in the arsenal of antivirals to combat HCV infection. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication."
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Affiliation(s)
- Isabel Fofana
- Inserm U1110, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Nikolaus Jilg
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Raymond T Chung
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Thomas F Baumert
- Inserm U1110, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA; Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
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42
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Progress towards a hepatitis C virus vaccine. Emerg Microbes Infect 2013; 2:e79. [PMID: 26038445 PMCID: PMC3924556 DOI: 10.1038/emi.2013.79] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 10/01/2013] [Accepted: 10/09/2013] [Indexed: 12/16/2022]
Abstract
New drugs to treat hepatitis C are expected to be approved over the next few years which promise to cure nearly all patients. However, due to issues of expected drug resistance, suboptimal activity against diverse hepatitis C virus (HCV) genotypes and especially because of their extremely high cost, it is unlikely that these HCV drugs will substantially reduce the world's HCV carrier population of around 170 million in the near future or the estimated global incidence of millions of new HCV infections. For these reasons, there is an urgent need to develop a prophylactic HCV vaccine and also to determine if therapeutic vaccines can aid in the treatment of chronically infected patients. After much early pessimism on the prospects for an effective prophylactic HCV vaccine, our recent knowledge of immune correlates of protection combined with the demonstrated immunogenicity and protective animal efficacies of various HCV vaccine candidates now allows for realistic optimism. This review summarizes the current rationale and status of clinical and experimental HCV vaccine candidates based on the elicitation of cross-neutralizing antibodies and broad cellular immune responses to this highly diverse virus.
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Gerold G, Pietschmann T. Opportunities and Risks of Host-targeting Antiviral Strategies for Hepatitis C. CURRENT HEPATITIS REPORTS 2013; 12:200-213. [PMID: 32214912 PMCID: PMC7089091 DOI: 10.1007/s11901-013-0187-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatitis C virus (HCV) infects more than 2 % of the world population with highest prevalence in parts of Africa and Asia. Past standard of care using interferon α and ribavirin had adverse effects and showed modest efficacy for some HCV genotypes spurring the development of direct acting antivirals (DAAs). Such DAAs target viral proteins and are thus better tolerated but they suffer from emergence of vial resistance. Furthermore, DAAs are often HCV genotype specific. Novel drug candidates targeting host factors required for HCV propagation, so called host-targeting antivirals (HTAs), promise to overcome both caveats. The genetic barrier to resistance is usually considered to be high for HTAs and all HCV genotypes presumably use the same host factors. Recent data, however, challenge these assumptions, at least for some HTAs. Here, we highlight the most important host-targeting strategies against hepatitis C and critically discuss their opportunities and risks.
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Affiliation(s)
- Gisa Gerold
- TWINCORE – Centre for Experimental and Clinical Infection Research, Institute of Experimental Virology, Feodor-Lynen-Str. 7, 30625 Hannover, Germany
| | - Thomas Pietschmann
- TWINCORE – Centre for Experimental and Clinical Infection Research, Institute of Experimental Virology, Feodor-Lynen-Str. 7, 30625 Hannover, Germany
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Functional analysis of claudin-6 and claudin-9 as entry factors for hepatitis C virus infection of human hepatocytes by using monoclonal antibodies. J Virol 2013; 87:10405-10. [PMID: 23864633 DOI: 10.1128/jvi.01691-13] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The relevance of claudin-6 and claudin-9 in hepatitis C virus (HCV) entry remains elusive. We produced claudin-6- or claudin-9-specific monoclonal antibodies that inhibit HCV entry into nonhepatic cells expressing exogenous claudin-6 or claudin-9. These antibodies had no effect on HCV infection of hepatoma cells or primary hepatocytes. Thus, although claudin-6 and claudin-9 can serve as entry factors in cell lines, HCV infection into human hepatocytes is not dependent on claudin-6 and claudin-9.
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Structural and antigenic definition of hepatitis C virus E2 glycoprotein epitopes targeted by monoclonal antibodies. Clin Dev Immunol 2013; 2013:450963. [PMID: 23935648 PMCID: PMC3722892 DOI: 10.1155/2013/450963] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 06/10/2013] [Indexed: 12/24/2022]
Abstract
Hepatitis C virus (HCV) is the major cause of chronic liver disease as well as the major indication for liver transplantation worldwide. Current standard of care is not completely effective, not administrable in grafted patients, and burdened by several side effects. This incomplete effectiveness is mainly due to the high propensity of the virus to continually mutate under the selective pressure exerted by the host immune response as well as currently administered antiviral drugs. The E2 envelope surface glycoprotein of HCV (HCV/E2) is the main target of the host humoral immune response and for this reason one of the major variable viral proteins. However, broadly cross-neutralizing monoclonal antibodies (mAbs) directed against HCV/E2 represent a promising tool for the study of virus-host interplay as well as for the development of effective prophylactic and therapeutic approaches. In the last few years many anti-HCV/E2 mAbs have been evaluated in preclinical and clinical trials as possible candidate antivirals, particularly for administration in pre- and post-transplant settings. In this review we summarize the antigenic and structural characteristics of HCV/E2 determined through the use of anti-HCV/E2 mAbs, which, given the absence of a crystal structure of this glycoprotein, represent currently the best tool available.
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