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Rani A, Stadler JT, Marsche G. HDL-based therapeutics: A promising frontier in combating viral and bacterial infections. Pharmacol Ther 2024; 260:108684. [PMID: 38964560 DOI: 10.1016/j.pharmthera.2024.108684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 06/03/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
Low levels of high-density lipoprotein (HDL) and impaired HDL functionality have been consistently associated with increased susceptibility to infection and its serious consequences. This has been attributed to the critical role of HDL in maintaining cellular lipid homeostasis, which is essential for the proper functioning of immune and structural cells. HDL, a multifunctional particle, exerts pleiotropic effects in host defense against pathogens. It functions as a natural nanoparticle, capable of sequestering and neutralizing potentially harmful substances like bacterial lipopolysaccharides. HDL possesses antiviral activity, preventing viruses from entering or fusing with host cells, thereby halting their replication cycle. Understanding the complex relationship between HDL and the immune system may reveal innovative targets for developing new treatments to combat infectious diseases and improve patient outcomes. This review aims to emphasize the role of HDL in influencing the course of bacterial and viral infections and its and its therapeutic potential.
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Affiliation(s)
- Alankrita Rani
- Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Styria, Austria
| | - Julia T Stadler
- Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Styria, Austria
| | - Gunther Marsche
- Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Styria, Austria; BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Styria, Austria.
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2
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Fierro NA, Rivera-Toledo E, Ávila-Horta F, Anaya-Covarrubias JY, Mendlovic F. Scavenger Receptors in the Pathogenesis of Viral Infections. Viral Immunol 2022; 35:175-191. [PMID: 35319302 DOI: 10.1089/vim.2021.0167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Scavenger receptors (SR) are not only pattern recognition receptors involved in the immune response against pathogens but are also important receptors exploited by different virus to enter host cells, and thus represent targets for antiviral therapy. The high mutation rates of viruses, as well as their small genomes are partly responsible for the high rates of virus resistance and effective treatments remain a challenge. Most currently approved formulations target viral-encoded factors. Nevertheless, host proteins may function as additional targets. Thus, there is a need to explore and develop new strategies aiming at cellular factors involved in virus replication and host cell entry. SR-virus interactions have implications in the pathogenesis of several viral diseases and in adenovirus-based vaccination and gene transfer technologies, and may function as markers of severe progression. Inhibition of SR could reduce adenoviral uptake and improve gene therapy and vaccination, as well as reduce pathogenesis. In this review, we will examine the crucial role of SR play in cell entry of different types of human virus, which will allow us to further understand their role in protection and pathogenesis and its potential as antiviral molecules. The recent discovery of SR-B1 as co-factor of SARS-Cov-2 (severe acute respiratory syndrome coronavirus 2) entry is also discussed. Further fundamental research is essential to understand molecular interactions in the dynamic virus-host cell interplay through SR for rational design of therapeutic strategies.
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Affiliation(s)
- Nora A Fierro
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Evelyn Rivera-Toledo
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Fernanda Ávila-Horta
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - Fela Mendlovic
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Facultad de Ciencias de la Salud, Universidad Anáhuac México Norte, Huixquilucan, Estado de México, Mexico
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3
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Entry Inhibitors of Hepatitis C Virus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1366:207-222. [DOI: 10.1007/978-981-16-8702-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Wang X, Wang Y, Ling Z, Zhang C, Fu M, Wang Y, Wang S, Zhang S, Shen Z. Peptide nucleic acid restores colistin susceptibility through modulation of MCR-1 expression in Escherichia coli. J Antimicrob Chemother 2021; 75:2059-2065. [PMID: 32417908 DOI: 10.1093/jac/dkaa140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 03/17/2020] [Accepted: 03/17/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Plasmid-mediated mechanisms of drug resistance accelerate the spread of polymyxin resistance, leaving clinicians with few or no antibacterial options for the treatment of infections caused by MDR bacteria, especially carbapenemase-producing strains. OBJECTIVES To evaluate the associations among promoter sequence variation, mcr-1 expression, host factors and levels of colistin resistance and to propose antisense agents such as peptide nucleic acids (PNAs) targeting mcr-1 as a tool to restore colistin susceptibility through modulation of MCR-1 expression in Escherichia coli. METHODS A β-galactosidase assay was performed to study mcr-1 promoter activity. Quantitative real-time PCR and western blot assays were used to identify the expression level of MCR-1 in WT strains and transformants. Three PNAs targeting different regions of mcr-1 were designed and synthesized to determine whether they can effectively inhibit MCR-1 expression. MIC was measured to test colistin susceptibility in the presence or absence of PNA-1 in mcr-1-carrying E. coli. RESULTS Variation in the mcr-1 promoter sequence and host species affect promoter activity, MCR-1 expression levels and colistin MICs. One PNA targeting the ribosome-binding site fully inhibited the expression of mcr-1 at a concentration of 4 μM, resulting in significantly increased susceptibility to colistin. The MIC90 of colistin decreased from 8 to 2 mg/L (P < 0.05) in the presence of 4 μM PNA. CONCLUSIONS These findings suggest that the antisense approach is a possible strategy to combat mcr-1-mediated resistance as well as other causes of emerging global resistance.
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Affiliation(s)
- Xiaoming Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.,MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yao Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing, China
| | - Zhuoren Ling
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Chaoyang Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Mingming Fu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yang Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Shaolin Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing, China
| | - Suxia Zhang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing, China
| | - Zhangqi Shen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing, China
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5
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Galle-Treger L, Moreau M, Ballaire R, Poupel L, Huby T, Sasso E, Troise F, Poti F, Lesnik P, Le Goff W, Gautier EL, Huby T. Targeted invalidation of SR-B1 in macrophages reduces macrophage apoptosis and accelerates atherosclerosis. Cardiovasc Res 2020; 116:554-565. [PMID: 31119270 DOI: 10.1093/cvr/cvz138] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 01/30/2019] [Accepted: 05/16/2019] [Indexed: 12/15/2022] Open
Abstract
AIMS SR-B1 is a cholesterol transporter that exerts anti-atherogenic properties in liver and peripheral tissues in mice. Bone marrow (BM) transfer studies suggested an atheroprotective role in cells of haematopoietic origin. Here, we addressed the specific contribution of SR-B1 in the monocyte/macrophage. METHODS AND RESULTS We generated mice deficient for SR-B1 in monocytes/macrophages (Lysm-Cre × SR-B1f/f) and transplanted their BM into Ldlr-/- mice. Fed a cholesterol-rich diet, these mice displayed accelerated aortic atherosclerosis characterized by larger macrophage-rich areas and decreased macrophage apoptosis compared with SR-B1f/f transplanted controls. These findings were reproduced in BM transfer studies using another atherogenic mouse recipient (SR-B1 KOliver × Cholesteryl Ester Transfer Protein). Haematopoietic reconstitution with SR-B1-/- BM conducted in parallel generated similar results to those obtained with Lysm-Cre × SR-B1f/f BM; thus suggesting that among haematopoietic-derived cells, SR-B1 exerts its atheroprotective role primarily in monocytes/macrophages. Consistent with our in vivo data, free cholesterol (FC)-induced apoptosis of macrophages was diminished in the absence of SR-B1. This effect could not be attributed to differential cellular cholesterol loading. However, we observed that expression of apoptosis inhibitor of macrophage (AIM) was induced in SR-B1-deficient macrophages, and notably upon FC-loading. Furthermore, we demonstrated that macrophages were protected from FC-induced apoptosis by AIM. Finally, AIM protein was found more present within the macrophage-rich area of the atherosclerotic lesions of SR-B1-deficient macrophages than controls. CONCLUSION Our findings suggest that macrophage SR-B1 plays a role in plaque growth by controlling macrophage apoptosis in an AIM-dependent manner.
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Affiliation(s)
| | - Martine Moreau
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | | | - Lucie Poupel
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Thomas Huby
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Emanuele Sasso
- Ceinge Biotecnologie Avanzate S.C.R.L, Via Gaetano Salvatore 486, 80145, Napoli, Italy.,Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, 80131, Napoli, Italy
| | - Fulvia Troise
- Ceinge Biotecnologie Avanzate S.C.R.L, Via Gaetano Salvatore 486, 80145, Napoli, Italy
| | - Francesco Poti
- Department of Medicine and Surgery, Unit of Neurosciences, University of Parma, Parma, Italy
| | - Philippe Lesnik
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | - Wilfried Le Goff
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
| | | | - Thierry Huby
- Sorbonne Université, INSERM, UMR_S 1166 ICAN, F-75013, Paris, France
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6
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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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7
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Cosset FL, Mialon C, Boson B, Granier C, Denolly S. HCV Interplay with Lipoproteins: Inside or Outside the Cells? Viruses 2020; 12:v12040434. [PMID: 32290553 PMCID: PMC7232430 DOI: 10.3390/v12040434] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/05/2020] [Accepted: 04/10/2020] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) infection is a major public health issue leading to chronic liver diseases. HCV particles are unique owing to their particular lipid composition, namely the incorporation of neutral lipids and apolipoproteins. The mechanism of association between HCV virion components and these lipoproteins factors remains poorly understood as well as its impact in subsequent steps of the viral life cycle, such as entry into cells. It was proposed that the lipoprotein biogenesis pathway is involved in HCV morphogenesis; yet, recent evidence indicated that HCV particles can mature and evolve biochemically in the extracellular medium after egress. In addition, several viral, cellular and blood components have been shown to influence and regulate this specific association. Finally, this specific structure and composition of HCV particles was found to influence entry into cells as well as their stability and sensitivity to neutralizing antibodies. Due to its specific particle composition, studying the association of HCV particles with lipoproteins remains an important goal towards the rational design of a protective vaccine.
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8
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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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9
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Gerold G, Moeller R, Pietschmann T. Hepatitis C Virus Entry: Protein Interactions and Fusion Determinants Governing Productive Hepatocyte Invasion. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a036830. [PMID: 31427285 DOI: 10.1101/cshperspect.a036830] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hepatitis C virus (HCV) entry is among the best-studied uptake processes for human pathogenic viruses. Uptake follows a spatially and temporally tightly controlled program. Numerous host factors including proteins, lipids, and glycans promote productive uptake of HCV particles into human liver cells. The virus initially attaches to surface proteoglycans, lipid receptors such as the scavenger receptor BI (SR-BI), and to the tetraspanin CD81. After lateral translocation of virions to tight junctions, claudin-1 (CLDN1) and occludin (OCLN) are essential for entry. Clathrin-mediated endocytosis engulfs HCV particles, which fuse with endosomal membranes after pH drop. Uncoating of the viral RNA genome in the cytoplasm completes the entry process. Here we systematically review and classify HCV entry factors by their mechanistic role, relevance, and level of evidence. Finally, we report on more recent knowledge on determinants of membrane fusion and close with an outlook on future implications of HCV entry research.
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Affiliation(s)
- Gisa Gerold
- TWINCORE, Center for Experimental and Clinical Infection Research, Institute for Experimental Virology, 30625 Hannover, Germany.,Department of Clinical Microbiology, Virology & Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, 901 85 Umeå, Sweden
| | - Rebecca Moeller
- TWINCORE, Center for Experimental and Clinical Infection Research, Institute for Experimental Virology, 30625 Hannover, Germany
| | - Thomas Pietschmann
- TWINCORE, Center for Experimental and Clinical Infection Research, Institute for Experimental Virology, 30625 Hannover, Germany
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10
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Marques PE, Nyegaard S, Collins RF, Troise F, Freeman SA, Trimble WS, Grinstein S. Multimerization and Retention of the Scavenger Receptor SR-B1 in the Plasma Membrane. Dev Cell 2019; 50:283-295.e5. [DOI: 10.1016/j.devcel.2019.05.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 04/05/2019] [Accepted: 05/10/2019] [Indexed: 10/26/2022]
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11
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Mansfield KM, Gilmore TD. Innate immunity and cnidarian-Symbiodiniaceae mutualism. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2019; 90:199-209. [PMID: 30268783 DOI: 10.1016/j.dci.2018.09.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 06/08/2023]
Abstract
The phylum Cnidaria (sea anemones, corals, hydra, jellyfish) is one the most distantly related animal phyla to humans, and yet cnidarians harbor many of the same cellular pathways involved in innate immunity in mammals. In addition to its role in pathogen recognition, the innate immune system has a role in managing beneficial microbes and supporting mutualistic microbial symbioses. Some corals and sea anemones undergo mutualistic symbioses with photosynthetic algae in the family Symbiodiniaceae. These symbioses can be disrupted by anthropogenic disturbances of ocean environments, which can have devastating consequences for the health of coral reef ecosystems. Several studies of cnidarian-Symbiodiniaceae symbiosis have implicated proteins in the host immune system as playing a role in both symbiont tolerance and loss of symbiosis (i.e., bleaching). In this review, we critically evaluate current knowledge about the role of host immunity in the regulation of symbiosis in cnidarians.
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Affiliation(s)
| | - Thomas D Gilmore
- Department of Biology, Boston University, Boston, MA, 02215, USA.
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12
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Monoclonal Antibodies against Occludin Completely Prevented Hepatitis C Virus Infection in a Mouse Model. J Virol 2018; 92:JVI.02258-17. [PMID: 29437969 DOI: 10.1128/jvi.02258-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 02/01/2018] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) entry into host cells is a multistep process requiring various host factors, including the tight junction protein occludin (OCLN), which has been shown to be essential for HCV infection in in vitro cell culture systems. However, it remains unclear whether OCLN is an effective and safe target for HCV therapy, owing to the lack of binders that can recognize the intact extracellular loop domains of OCLN and prevent HCV infection. In this study, we successfully generated four rat anti-OCLN monoclonal antibodies (MAbs) by the genetic immunization method and unique cell differential screening. These four MAbs bound to human OCLN with a very high affinity (antibody dissociation constant of <1 nM). One MAb recognized the second loop of human and mouse OCLN, whereas the three other MAbs recognized the first loop of human OCLN. All MAbs inhibited HCV infection in Huh7.5.1-8 cells in a dose-dependent manner without apparent cytotoxicity. Additionally, the anti-OCLN MAbs prevented both cell-free HCV infection and cell-to-cell HCV transmission. Kinetic studies with anti-OCLN and anti-claudin-1 (CLDN1) MAbs demonstrated that OCLN interacts with HCV after CLDN1 in the internalization step. Two selected MAbs completely inhibited HCV infection in human liver chimeric mice without apparent adverse effects. Therefore, OCLN would be an appropriate host target for anti-HCV entry inhibitors, and anti-OCLN MAbs may be promising candidates for novel anti-HCV agents, particularly in combination with direct-acting HCV antiviral agents.IMPORTANCE HCV entry into host cells is thought to be a very complex process involving various host entry factors, such as the tight junction proteins claudin-1 and OCLN. In this study, we developed novel functional MAbs that recognize intact extracellular domains of OCLN, which is essential for HCV entry into host cells. The established MAbs against OCLN, which had very high affinity and selectivity for intact OCLN, strongly inhibited HCV infection both in vitro and in vivo Using these anti-OCLN MAbs, we found that OCLN is necessary for the later stages of HCV entry. These anti-OCLN MAbs are likely to be very useful for understanding the OCLN-mediated HCV entry mechanism and might be promising candidates for novel HCV entry inhibitors.
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13
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Bridge SH, Pagano S, Jones M, Foster GR, Neely D, Vuilleumier N, Bassendine MF. Autoantibody to apolipoprotein A-1 in hepatitis C virus infection: a role in atherosclerosis? Hepatol Int 2018; 12:17-25. [PMID: 29423541 PMCID: PMC5814532 DOI: 10.1007/s12072-018-9842-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/08/2018] [Indexed: 12/22/2022]
Abstract
Background/purpose One to three per cent of the world’s population has hepatitis C virus (HCV) infection, which is not only a major cause of liver disease and cancer but also associated with an increased risk of atherosclerosis, despite an ostensibly favourable lipid profile. Autoantibodies are frequent in HCV infection and emerging evidence shows that autoantibodies could be valuable for cardiovascular disease (CVD) risk stratification. This study investigated a novel independent biomarker of CVD, autoantibodies to apolipoprotein A-1 (anti-apoA-1 IgG) and lipids in patients with chronic HCV before, during and after direct-acting anti-viral (DAA) therapy. Methods Eighty-nine blinded serum samples from 27 patients with advanced chronic HCV were assayed for lipids and anti-apoA-1 IgG by ELISA. Results Pre-treatment HCV viral load correlated with high-density lipoprotein cholesterol (HDL-C, r = 0.417; p = 0.042) and negatively with apolipoprotein (apo)B (r = − 0.497; p = 0.013) and markers of CVD risk, the apoB/apoA-1 ratio (r = − 0.490; p = 0.015) and triglyceride level (TG)/HDL-C ratio (r = − 0.450; p = 0.031). Fourteen (52%) of 27 patients had detectable anti-apoA-1 IgG autoantibodies pre-treatment; only two became undetectable with virological cure. Autoantibody-positive sera had lower apoA-1 (p = 0.012), HDL-C (p = 0.009) and total cholesterol (p = 0.006) levels. Conclusions This is the first report of the presence of an emerging biomarker for atherosclerosis, anti-apoA-1 IgG, in some patients with HCV infection. It may be induced by apoA-1 on the surface of HCV lipoviral particles. The autoantibodies inversely correlate with apoA-1 and HDL levels and may render HDL dysfunctional. Whether these hypothesis-generating findings have clinical implications in HCV patients requires further study.
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Affiliation(s)
- Simon H Bridge
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Sabrina Pagano
- Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Meleri Jones
- The Liver Unit, Blizard Institute, Queen Mary University of London, London, UK
| | - Graham R Foster
- The Liver Unit, Blizard Institute, Queen Mary University of London, London, UK
| | - Dermot Neely
- Department of Clinical Biochemistry, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Nicolas Vuilleumier
- Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Margaret F Bassendine
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK. .,Department of Hepatology and Gastroenterology, Imperial College London, 10th Floor QEQM Wing, St. Mary's Hospital Campus, South Wharf Street, London, W2 1NY, UK.
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14
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Fung KY, Wang C, Nyegaard S, Heit B, Fairn GD, Lee WL. SR-BI Mediated Transcytosis of HDL in Brain Microvascular Endothelial Cells Is Independent of Caveolin, Clathrin, and PDZK1. Front Physiol 2017; 8:841. [PMID: 29163190 PMCID: PMC5670330 DOI: 10.3389/fphys.2017.00841] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/09/2017] [Indexed: 01/19/2023] Open
Abstract
The vascular endothelium supplying the brain exhibits very low paracellular and transcellular permeability and is a major constituent of the blood-brain barrier. High-density lipoprotein (HDL) crosses the blood-brain barrier by transcytosis, but technical limitations have made it difficult to elucidate its regulation. Using a combination of spinning-disc confocal and total internal reflection fluorescence microscopy, we examined the uptake and transcytosis of HDL by human primary brain microvascular endothelial cell monolayers. Using these approaches, we report that HDL internalization requires dynamin but not clathrin heavy chain and that its internalization and transcytosis are saturable. Internalized HDL partially co-localized with the scavenger receptor BI (SR-BI) and knockdown of SR-BI significantly attenuated HDL internalization. However, we observed that the adaptor protein PDZK1—which is critical to HDL-SR-BI signaling in other tissues—is not required for HDL uptake in these cells. Additionally, while these cells express caveolin, the abundance of caveolae in this tissue is negligible and we find that SR-BI and caveolin do not co-fractionate. Furthermore, direct silencing of caveolin-1 had no impact on the uptake of HDL. Finally, inhibition of endothelial nitric oxide synthase increased HDL internalization while increasing nitric oxide levels had no impact. Together, these data indicate that SR-BI-mediated transcytosis in brain microvascular endothelial cells is distinct from uptake and signaling pathways described for this receptor in other cell types.
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Affiliation(s)
- Karen Y Fung
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Center for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Changsen Wang
- Keenan Research Center for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Steffen Nyegaard
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - Bryan Heit
- Department of Microbiology and Immunology, Centre for Human Immunology, University of Western Ontario, London, ON, Canada
| | - Gregory D Fairn
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Center for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Surgery, University of Toronto, ON, Canada
| | - Warren L Lee
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Center for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Departments of Medicine and Laboratory Medicine and Pathobiology, University of Toronto, ON, Canada
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15
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Abstract
Hepatitis C virus (HCV) consists of envelope proteins, core proteins, and genome RNA. The structural genes and non-structural genes in the open reading frame of its genome encode functional proteins essential to viral life cycles, ranging from virus attachment to progeny virus secretion. After infection, the host cells suffer damage from virus-induced oxidative stress, steatosis, and activation of proto-oncogenes. Every process during the viral life cycle can be considered as targets for direct acting antivirals. However, protective immunity cannot be easily acquired for the volatility in HCV antigenic epitopes. Understanding its molecular characteristics, especially pathogenesis and targets the drugs act on, not only helps professionals to make optimal therapeutic decisions, but also helps clinicians who do not specialize in infectious diseases/hepatology to provide better management for patients. This review serves to provide an insight for clinicians and this might provide a possible solution for any possible collision.
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Affiliation(s)
- Lingyao Du
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China. E-mail.
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16
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Oliveira C, Fournier C, Descamps V, Morel V, Scipione CA, Romagnuolo R, Koschinsky ML, Boullier A, Marcelo P, Domon J, Brochot E, Duverlie G, Francois C, Castelain S, Helle F. Apolipoprotein(a) inhibits hepatitis C virus entry through interaction with infectious particles. Hepatology 2017; 65:1851-1864. [PMID: 28152568 PMCID: PMC5488163 DOI: 10.1002/hep.29096] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/09/2017] [Accepted: 01/25/2017] [Indexed: 01/08/2023]
Abstract
UNLABELLED The development of different cell culture models has greatly contributed to increased understanding of the hepatitis C virus (HCV) life cycle. However, it is still challenging to grow HCV clinical isolates in cell culture. If overcome, this would open new perspectives to study HCV biology, including drug-resistant variants emerging with new antiviral therapies. In this study we hypothesized that this hurdle could be due to the presence of inhibitory factors in patient serum. Combining polyethylene glycol precipitation, iodixanol gradient, and size-exclusion chromatography, we obtained from HCV-seronegative sera a purified fraction enriched in inhibitory factors. Mass spectrometric analysis identified apolipoprotein(a) (apo[a]) as a potential inhibitor of HCV entry. Apo(a) consists of 10 kringle IV domains (KIVs), one kringle V domain, and an inactive protease domain. The 10 KIVs are present in a single copy with the exception of KIV type 2 (KIV2 ), which is encoded in a variable number of tandemly repeated copies, giving rise to numerous apo(a) size isoforms. In addition, apo(a) covalently links to the apolipoprotein B component of a low-density lipoprotein through a disulfide bridge to form lipoprotein(a). Using a recombinant virus derived from the JFH1 strain, we confirmed that plasma-derived and recombinant lipoprotein(a) as well as purified recombinant apo(a) variants were able to specifically inhibit HCV by interacting with infectious particles. Our results also suggest that small isoforms are less inhibitory than the large ones. Finally, we observed that the lipoprotein moiety of HCV lipoviroparticles was essential for inhibition, whereas functional lysine-binding sites in KIV7 , KIV8 , and KIV10 were not required. CONCLUSIONS Our results identify apo(a) as an additional component of the lipid metabolism modulating HCV infection. (Hepatology 2017;65:1851-1864).
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Affiliation(s)
- Catarina Oliveira
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Carole Fournier
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Véronique Descamps
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Virginie Morel
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Corey A. Scipione
- Robarts Research Institute, Schulich School of Medicine & DentistryWestern UniversityLondonONCanada
| | - Rocco Romagnuolo
- Department of Chemistry & BiochemistryUniversity of WindsorWindsorONCanada
| | - Marlys L. Koschinsky
- Robarts Research Institute, Schulich School of Medicine & DentistryWestern UniversityLondonONCanada
| | - Agnès Boullier
- INSERM U1088, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Paulo Marcelo
- Plateforme ICAP, Centre Universitaire de Recherche en Santé, Université de Picardie Jules VerneAmiensFrance
| | - Jean‐Marc Domon
- EA3900 BIOPI, Biologie des Plantes et Innovation, UFR des Sciences, Université de Picardie Jules VerneAmiensFrance
| | - Etienne Brochot
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Gilles Duverlie
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance,Biobanque de Picardie, Centre Hospitalier UniversitaireAmiensFrance
| | - Catherine Francois
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Sandrine Castelain
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
| | - Francois Helle
- EA4294, Laboratoire de Virologie, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules VerneAmiensFrance
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17
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Regulated Entry of Hepatitis C Virus into Hepatocytes. Viruses 2017; 9:v9050100. [PMID: 28486435 PMCID: PMC5454413 DOI: 10.3390/v9050100] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/24/2017] [Accepted: 05/02/2017] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) is a model for the study of virus–host interaction and host cell responses to infection. Virus entry into hepatocytes is the first step in the HCV life cycle, and this process requires multiple receptors working together. The scavenger receptor class B type I (SR-BI) and claudin-1 (CLDN1), together with human cluster of differentiation (CD) 81 and occludin (OCLN), constitute the minimal set of HCV entry receptors. Nevertheless, HCV entry is a complex process involving multiple host signaling pathways that form a systematic regulatory network; this network is centrally controlled by upstream regulators epidermal growth factor receptor (EGFR) and transforming growth factor β receptor (TGFβ-R). Further feedback regulation and cell-to-cell spread of the virus contribute to the chronic maintenance of HCV infection. A comprehensive and accurate disclosure of this critical process should provide insights into the viral entry mechanism, and offer new strategies for treatment regimens and targets for HCV therapeutics.
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18
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Saeed AFUH, Wang R, Ling S, Wang S. Antibody Engineering for Pursuing a Healthier Future. Front Microbiol 2017; 8:495. [PMID: 28400756 PMCID: PMC5368232 DOI: 10.3389/fmicb.2017.00495] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/09/2017] [Indexed: 12/21/2022] Open
Abstract
Since the development of antibody-production techniques, a number of immunoglobulins have been developed on a large scale using conventional methods. Hybridoma technology opened a new horizon in the production of antibodies against target antigens of infectious pathogens, malignant diseases including autoimmune disorders, and numerous potent toxins. However, these clinical humanized or chimeric murine antibodies have several limitations and complexities. Therefore, to overcome these difficulties, recent advances in genetic engineering techniques and phage display technique have allowed the production of highly specific recombinant antibodies. These engineered antibodies have been constructed in the hunt for novel therapeutic drugs equipped with enhanced immunoprotective abilities, such as engaging immune effector functions, effective development of fusion proteins, efficient tumor and tissue penetration, and high-affinity antibodies directed against conserved targets. Advanced antibody engineering techniques have extensive applications in the fields of immunology, biotechnology, diagnostics, and therapeutic medicines. However, there is limited knowledge regarding dynamic antibody development approaches. Therefore, this review extends beyond our understanding of conventional polyclonal and monoclonal antibodies. Furthermore, recent advances in antibody engineering techniques together with antibody fragments, display technologies, immunomodulation, and broad applications of antibodies are discussed to enhance innovative antibody production in pursuit of a healthier future for humans.
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Affiliation(s)
- Abdullah F U H Saeed
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Rongzhi Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Sumei Ling
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Shihua Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
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19
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Vercauteren K, Brown RJP, Mesalam AA, Doerrbecker J, Bhuju S, Geffers R, Van Den Eede N, McClure CP, Troise F, Verhoye L, Baumert T, Farhoudi A, Cortese R, Ball JK, Leroux-Roels G, Pietschmann T, Nicosia A, Meuleman P. Targeting a host-cell entry factor barricades antiviral-resistant HCV variants from on-therapy breakthrough in human-liver mice. Gut 2016; 65:2029-2034. [PMID: 26306759 DOI: 10.1136/gutjnl-2014-309045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 07/22/2015] [Accepted: 07/23/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Direct-acting antivirals (DAAs) inhibit hepatitis C virus (HCV) infection by targeting viral proteins that play essential roles in the replication process. However, selection of resistance-associated variants (RAVs) during DAA therapy has been a cause of therapeutic failure. In this study, we wished to address whether such RAVs could be controlled by the co-administration of host-targeting entry inhibitors that prevent intrahepatic viral spread. DESIGN We investigated the effect of adding an entry inhibitor (the anti-scavenger receptor class B type I mAb1671) to a DAA monotherapy (the protease inhibitor ciluprevir) in human-liver mice chronically infected with HCV of genotype 1b. Clinically relevant non-laboratory strains were used to achieve viraemia consisting of a cloud of related viral variants (quasispecies) and the emergence of RAVs was monitored at high resolution using next-generation sequencing. RESULTS HCV-infected human-liver mice receiving DAA monotherapy rapidly experienced on-therapy viral breakthrough. Deep sequencing of the HCV protease domain confirmed the manifestation of drug-resistant mutants upon viral rebound. In contrast, none of the mice treated with a combination of the DAA and the entry inhibitor experienced on-therapy viral breakthrough, despite detection of RAV emergence in some animals. CONCLUSIONS This study provides preclinical in vivo evidence that addition of an entry inhibitor to an anti-HCV DAA regimen restricts the breakthrough of DAA-resistant viruses. Our approach is an excellent strategy to prevent therapeutic failure caused by on-therapy rebound of DAA-RAVs. Inclusion of an entry inhibitor to the newest DAA combination therapies may further increase response rates, especially in difficult-to-treat patient populations.
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Affiliation(s)
- Koen Vercauteren
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | - 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 Centre for Infection Research (HZI), Hannover, Germany
| | - Ahmed Atef Mesalam
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | - Juliane Doerrbecker
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Sabin Bhuju
- Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Robert Geffers
- Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Naomi Van Den Eede
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | - C Patrick McClure
- School of Life Sciences and the NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Queen's Medical Centre, Nottingham, UK
| | | | - Lieven Verhoye
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | - Thomas Baumert
- Institut National de la Santé et de la Recherche Médicale, U1110, Strasbourg, France.,Université de Strasbourg, Strasbourg et Pole Hépato-digestif, Hopitaux Universitaires de Strasbourg, Strasbourg, France
| | - Ali Farhoudi
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | | | - Jonathan K Ball
- School of Life Sciences and the NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Queen's Medical Centre, Nottingham, UK
| | - Geert Leroux-Roels
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
| | - 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 Centre for Infection Research (HZI), Hannover, Germany.,German Centre for Infection Research (DZIF), Partner site Hannover-Braunschweig, Hannover, Germany
| | - Alfredo Nicosia
- CEINGE, Naples, Italy.,Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Philip Meuleman
- Department Clinical Chemistry, Microbiology and Immunology, Center for Vaccinology, Ghent University, Ghent, Belgium
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20
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Alsaleh NB, Persaud I, Brown JM. Silver Nanoparticle-Directed Mast Cell Degranulation Is Mediated through Calcium and PI3K Signaling Independent of the High Affinity IgE Receptor. PLoS One 2016; 11:e0167366. [PMID: 27907088 PMCID: PMC5131952 DOI: 10.1371/journal.pone.0167366] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 11/13/2016] [Indexed: 12/20/2022] Open
Abstract
Engineered nanomaterial (ENM)-mediated toxicity often involves triggering immune responses. Mast cells can regulate both innate and adaptive immune responses and are key effectors in allergic diseases and inflammation. Silver nanoparticles (AgNPs) are one of the most prevalent nanomaterials used in consumer products due to their antimicrobial properties. We have previously shown that AgNPs induce mast cell degranulation that was dependent on nanoparticle physicochemical properties. Furthermore, we identified a role for scavenger receptor B1 (SR-B1) in AgNP-mediated mast cell degranulation. However, it is completely unknown how SR-B1 mediates mast cell degranulation and the intracellular signaling pathways involved. In the current study, we hypothesized that SR-B1 interaction with AgNPs directs mast cell degranulation through activation of signal transduction pathways that culminate in an increase in intracellular calcium signal leading to mast cell degranulation. For these studies, we utilized bone marrow-derived mast cells (BMMC) isolated from C57Bl/6 mice and RBL-2H3 cells (rat basophilic leukemia cell line). Our data support our hypothesis and show that AgNP-directed mast cell degranulation involves activation of PI3K, PLCγ and an increase in intracellular calcium levels. Moreover, we found that influx of extracellular calcium is required for the cells to degranulate in response to AgNP exposure and is mediated at least partially via the CRAC channels. Taken together, our results provide new insights into AgNP-induced mast cell activation that are key for designing novel ENMs that are devoid of immune system activation.
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Affiliation(s)
- Nasser B. Alsaleh
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Indushekhar Persaud
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Jared M. Brown
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
- * E-mail:
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21
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Neubauer EF, Poole AZ, Weis VM, Davy SK. The scavenger receptor repertoire in six cnidarian species and its putative role in cnidarian-dinoflagellate symbiosis. PeerJ 2016; 4:e2692. [PMID: 27896028 PMCID: PMC5119243 DOI: 10.7717/peerj.2692] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/15/2016] [Indexed: 01/01/2023] Open
Abstract
Many cnidarians engage in a mutualism with endosymbiotic photosynthetic dinoflagellates that forms the basis of the coral reef ecosystem. Interpartner interaction and regulation includes involvement of the host innate immune system. Basal metazoans, including cnidarians have diverse and complex innate immune repertoires that are just beginning to be described. Scavenger receptors (SR) are a diverse superfamily of innate immunity genes that recognize a broad array of microbial ligands and participate in phagocytosis of invading microbes. The superfamily includes subclades named SR-A through SR-I that are categorized based on the arrangement of sequence domains including the scavenger receptor cysteine rich (SRCR), the C-type lectin (CTLD) and the CD36 domains. Previous functional and gene expression studies on cnidarian-dinoflagellate symbiosis have implicated SR-like proteins in interpartner communication and regulation. In this study, we characterized the SR repertoire from a combination of genomic and transcriptomic resources from six cnidarian species in the Class Anthozoa. We combined these bioinformatic analyses with functional experiments using the SR inhibitor fucoidan to explore a role for SRs in cnidarian symbiosis and immunity. Bioinformatic searches revealed a large diversity of SR-like genes that resembled SR-As, SR-Bs, SR-Es and SR-Is. SRCRs, CTLDs and CD36 domains were identified in multiple sequences in combinations that were highly homologous to vertebrate SRs as well as in proteins with novel domain combinations. Phylogenetic analyses of CD36 domains of the SR-B-like sequences from a diversity of metazoans grouped cnidarian with bilaterian sequences separate from other basal metazoans. All cnidarian sequences grouped together with moderate support in a subclade separately from bilaterian sequences. Functional experiments were carried out on the sea anemone Aiptasia pallida that engages in a symbiosis with Symbiodinium minutum (clade B1). Experimental blocking of the SR ligand binding site with the inhibitor fucoidan reduced the ability of S. minutum to colonize A. pallida suggesting that host SRs play a role in host-symbiont recognition. In addition, incubation of symbiotic anemones with fucoidan elicited an immune response, indicating that host SRs function in immune modulation that results in host tolerance of the symbionts.
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Affiliation(s)
- Emilie F. Neubauer
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Angela Z. Poole
- Department of Biology, Western Oregon University, Monmouth, OR, United States
| | - Virginia M. Weis
- Department of Integrative Biology, Oregon State University, Corvallis, OR, United States
| | - Simon K. Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
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22
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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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23
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Yamamoto S, Fukuhara T, Ono C, Uemura K, Kawachi Y, Shiokawa M, Mori H, Wada M, Shima R, Okamoto T, Hiraga N, Suzuki R, Chayama K, Wakita T, Matsuura Y. Lipoprotein Receptors Redundantly Participate in Entry of Hepatitis C Virus. PLoS Pathog 2016; 12:e1005610. [PMID: 27152966 PMCID: PMC4859476 DOI: 10.1371/journal.ppat.1005610] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 04/12/2016] [Indexed: 02/07/2023] Open
Abstract
Scavenger receptor class B type 1 (SR-B1) and low-density lipoprotein receptor (LDLR) are known to be involved in entry of hepatitis C virus (HCV), but their precise roles and their interplay are not fully understood. In this study, deficiency of both SR-B1 and LDLR in Huh7 cells was shown to impair the entry of HCV more strongly than deficiency of either SR-B1 or LDLR alone. In addition, exogenous expression of not only SR-B1 and LDLR but also very low-density lipoprotein receptor (VLDLR) rescued HCV entry in the SR-B1 and LDLR double-knockout cells, suggesting that VLDLR has similar roles in HCV entry. VLDLR is a lipoprotein receptor, but the level of its hepatic expression was lower than those of SR-B1 and LDLR. Moreover, expression of mutant lipoprotein receptors incapable of binding to or uptake of lipid resulted in no or slight enhancement of HCV entry in the double-knockout cells, suggesting that binding and/or uptake activities of lipid by lipoprotein receptors are essential for HCV entry. In addition, rescue of infectivity in the double-knockout cells by the expression of the lipoprotein receptors was not observed following infection with pseudotype particles bearing HCV envelope proteins produced in non-hepatic cells, suggesting that lipoproteins associated with HCV particles participate in the entry through their interaction with lipoprotein receptors. Buoyant density gradient analysis revealed that HCV utilizes these lipoprotein receptors in a manner dependent on the lipoproteins associated with HCV particles. Collectively, these results suggest that lipoprotein receptors redundantly participate in the entry of HCV. Hepatitis C virus (HCV) utilizes several receptors to enter hepatocytes, including scavenger receptor class B type 1 (SR-B1) receptor and low-density lipoprotein receptor (LDLR). HCV particles interact with lipoprotein and apolipoproteins to form complexes termed lipoviroparticles. Several reports have shown that SR-B1 and LDLR participate in the entry of lipoviroparticles through interaction with lipoproteins. However, the precise roles of SR-B1 and LDLR in HCV entry have not been fully clarified. In this study, we showed that SR-B1 and LDLR have a redundant role in HCV entry. In addition, we showed that very low-density lipoprotein receptor (VLDLR) played a role in HCV entry similar to the roles of SR-B1 and LDLR. Interestingly, VLDLR expression was low in the liver in contrast to the abundant expressions of SR-B1 and LDLR, but high in several extrahepatic tissues. Our data suggest that lipoprotein receptors participate in the entry of HCV particles associated with various lipoproteins.
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Affiliation(s)
- Satomi Yamamoto
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Takasuke Fukuhara
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Chikako Ono
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Kentaro Uemura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Yukako Kawachi
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Mai Shiokawa
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Hiroyuki Mori
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Masami Wada
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Ryoichi Shima
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Toru Okamoto
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Nobuhiko Hiraga
- Department of Gastroenterology and Metabolism, Applied Life Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Ryosuke Suzuki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kazuaki Chayama
- Department of Gastroenterology and Metabolism, Applied Life Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
- * E-mail:
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24
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The physiological expression of scavenger receptor SR-B1 in canine endometrial and placental epithelial cells and its potential involvement in pathogenesis of pyometra. Theriogenology 2016; 85:1599-1609.e2. [PMID: 26898415 DOI: 10.1016/j.theriogenology.2016.01.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 01/22/2016] [Accepted: 01/23/2016] [Indexed: 12/20/2022]
Abstract
Pyometra, the purulent inflammation of the uterus, is a common uterine disease of bitches that has potentially life-threatening consequences. The opportunistic bacterial infection of the uterus often progresses into the serious systemic inflammatory response syndrome. In a previous study, we characterized epithelial foam cells in the canine endometrial surface occurring in metestrus, and we regularly observed pronounced epithelial foam-cell formations in pyometra-affected uteri. Therefore, it was assumed that the mechanism behind lipid droplet accumulation in surface epithelial cells might even increase bacterial binding capacity and promote pyometra development. Lipid droplet accumulation in epithelial cells is accomplished via specialized lipid receptors called scavenger receptors (SR). Scavenger receptor class B type 1 (SR-B1) is an important receptor for lipid accumulation in diverse cell types, but it is also a strong binding partner for bacteria, and thereby enhances bacterial adhesion and clinical signs of systemic inflammatory response syndrome. In the present study, after the isolation of metestrous surface epithelial cells from canine uteri by laser capture microdissection, SR-B1 was identified at the messenger RNA (mRNA) level by quantitative real time polymerase chain reaction and also at the protein level by means of immunohistochemistry. In pyometra-affected uteri, SR-B1 mRNA expression was higher than that in the healthy control samples, and SR-B1 protein was expressed in the surface and crypt epithelial cells. Furthermore, to understand the physiological role of SR-B1 expression in the metestrus surface epithelial cells, we investigated its expression in the epithelial cells of the glandular chambers of canine placenta in different stages of gestation because these cells are also characterized by lipid droplet accumulation. SR-B1 was present in the placental epithelial cells of the glandular chambers from 25 to 30 and 45 to 50 days of gestation, where basal and basal and/or apical expression patterns were observed. The physiological expression of SR-B1 in metestrous endometrial surface epithelia might be related to the implantation process and embryo development, as SR-B1 was also identified in the epithelial cells of the canine placental chambers. The increased levels of SR-B1 in pyometra-affected uteri indicate a potential role for this scavenger receptor in endometrial bacterial adhesion.
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25
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Qian XJ, Zhu YZ, Zhao P, Qi ZT. Entry inhibitors: New advances in HCV treatment. Emerg Microbes Infect 2016; 5:e3. [PMID: 26733381 PMCID: PMC4735057 DOI: 10.1038/emi.2016.3] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 10/28/2015] [Accepted: 11/02/2015] [Indexed: 12/11/2022]
Abstract
Hepatitis C virus (HCV) infection affects approximately 3% of the world's population and causes chronic liver diseases, including liver fibrosis, cirrhosis, and hepatocellular carcinoma. Although current antiviral therapy comprising direct-acting antivirals (DAAs) can achieve a quite satisfying sustained virological response (SVR) rate, it is still limited by viral resistance, long treatment duration, combined adverse reactions, and high costs. Moreover, the currently marketed antivirals fail to prevent graft reinfections in HCV patients who receive liver transplantations, probably due to the cell-to-cell transmission of the virus, which is also one of the main reasons behind treatment failure. HCV entry is a highly orchestrated process involving initial attachment and binding, post-binding interactions with host cell factors, internalization, and fusion between the virion and the host cell membrane. Together, these processes provide multiple novel and promising targets for antiviral therapy. Most entry inhibitors target host cell components with high genetic barriers and eliminate viral infection from the very beginning of the viral life cycle. In future, the addition of entry inhibitors to a combination of treatment regimens might optimize and widen the prevention and treatment of HCV infection. This review summarizes the molecular mechanisms and prospects of the current preclinical and clinical development of antiviral agents targeting HCV entry.
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Affiliation(s)
- Xi-Jing Qian
- Shanghai Key Laboratory of Medical Biodefense, Department of Microbiology, Second Military Medical University, Shanghai 200433, China
| | - Yong-Zhe Zhu
- Shanghai Key Laboratory of Medical Biodefense, Department of Microbiology, Second Military Medical University, Shanghai 200433, China
| | - Ping Zhao
- Shanghai Key Laboratory of Medical Biodefense, Department of Microbiology, Second Military Medical University, Shanghai 200433, China
| | - Zhong-Tian Qi
- Shanghai Key Laboratory of Medical Biodefense, Department of Microbiology, Second Military Medical University, Shanghai 200433, China
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One-Step Recovery of scFv Clones from High-Throughput Sequencing-Based Screening of Phage Display Libraries Challenged to Cells Expressing Native Claudin-1. BIOMED RESEARCH INTERNATIONAL 2015; 2015:703213. [PMID: 26649313 PMCID: PMC4662980 DOI: 10.1155/2015/703213] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 10/05/2015] [Indexed: 01/09/2023]
Abstract
Expanding the availability of monoclonal antibodies interfering with hepatitis C virus infection of hepatocytes is an active field of investigation within medical biotechnologies, to prevent graft reinfection in patients subjected to liver transplantation and to overcome resistances elicited by novel antiviral drugs. In this paper, we describe a complete pipeline for screening of phage display libraries of human scFvs against native Claudin-1, a tight-junction protein involved in hepatitis C virus infection, expressed on the cell surface of human hepatocytes. To this aim, we implemented a high-throughput sequencing approach for library screening, followed by a simple and effective strategy to recover active binder clones from enriched sublibraries. The recovered clones were successfully converted to active immunoglobulins, thus demonstrating the effectiveness of the whole procedure. This novel approach can guarantee rapid and cheap isolation of antibodies for virtually any native antigen involved in human diseases, for therapeutic and/or diagnostic applications.
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Paciello R, Urbanowicz RA, Riccio G, Sasso E, McClure CP, Zambrano N, Ball JK, Cortese R, Nicosia A, De Lorenzo C. Novel human anti-claudin 1 mAbs inhibit hepatitis C virus infection and may synergize with anti-SRB1 mAb. J Gen Virol 2015; 97:82-94. [PMID: 26519290 DOI: 10.1099/jgv.0.000330] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hepatitis C virus (HCV) is a major cause of chronic hepatitis and liver carcinoma and new therapies based on novel targets are needed. The tight junction protein claudin 1 (CLDN-1) is essential for HCV cell entry and spread, and anti-CLDN-1 rat and mouse mAbs are safe and effective in preventing and treating HCV infection in a human liver chimeric mouse model. To accelerate translation of these observations into a novel approach to treat HCV infection and disease in humans, we screened a phage display library of human single-chain antibody fragments by using a panel of CLDN-1-positive and -negative cell lines and identified phage specifically binding to CLDN-1. The 12 clones showing the highest levels of binding were converted into human IgG4. Some of these mAbs displayed low-nanomolar affinity, and inhibited infection of human hepatoma Huh7.5 cells by different HCV isolates in a dose-dependent manner. Cross-competition experiments identified six inhibitory mAbs that recognized distinct epitopes. Combination of the human anti-SRB1 mAb C-1671 with these anti-CLDN-1 mAbs could either increase or reduce inhibition of cell culture-derived HCV infection in vitro. These novel human anti-CLDN-1 mAbs are potentially useful to develop a new strategy for anti-HCV therapy and lend support to the combined use of antibodies targeting the HCV receptors CLDN-1 and SRB1, but indicate that care must be taken in selecting the proper combination.
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Affiliation(s)
- Rolando Paciello
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
| | - Richard A Urbanowicz
- School of Life Sciences, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
- NIHR Nottingham Digestive Diseases Centre, Biomedical Research Unit, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
| | - Gennaro Riccio
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
| | - Emanuele Sasso
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
| | - C Patrick McClure
- School of Life Sciences, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
- NIHR Nottingham Digestive Diseases Centre, Biomedical Research Unit, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
| | - Nicola Zambrano
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
| | - Jonathan K Ball
- School of Life Sciences, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
- NIHR Nottingham Digestive Diseases Centre, Biomedical Research Unit, The University of Nottingham, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, UK
| | | | - Alfredo Nicosia
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
| | - Claudia De Lorenzo
- Ceinge - Biotecnologie Avanzate s.c. a.r.l., via Gaetano Salvatore 486, 80145 Napoli, Italy
- Department of Molecular Medicine and Medical Biotechnology, University of Naples 'Federico II', via Pansini 5, 80131 Napoli, Italy
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Nawaz A, Zaidi SF, Usmanghani K, Ahmad I. Concise review on the insight of hepatitis C. J Taibah Univ Med Sci 2015. [DOI: 10.1016/j.jtumed.2014.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Pozzuto T, Röger C, Kurreck J, Fechner H. Enhanced suppression of adenovirus replication by triple combination of anti-adenoviral siRNAs, soluble adenovirus receptor trap sCAR-Fc and cidofovir. Antiviral Res 2015; 120:72-8. [PMID: 26026665 DOI: 10.1016/j.antiviral.2015.05.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/21/2015] [Accepted: 05/26/2015] [Indexed: 01/04/2023]
Abstract
Adenoviruses (Ad) generally induce mild self-limiting respiratory or intestinal infections but can also cause serious disease with fatal outcomes in immunosuppressed patients. Antiviral drug therapy is an important treatment for adenoviral infections but its efficiency is limited. Recently, we have shown that gene silencing by RNA interference (RNAi) is a promising new approach to inhibit adenoviral infection. In the present in vitro study, we examined whether the efficiency of an RNAi-based anti-adenoviral therapy can be further increased by combination with a virus receptor trap sCAR-Fc and with the antiviral drug cidofovir. Initially, three siRNAs, siE1A_4, siIVa2_2 and Pol-si2, targeting the adenoviral E1A, IVa2 and DNA polymerase mRNAs, respectively, were used for gene silencing. Replication of the Ad was inhibited in a dose dependent manner by each siRNA, but the efficiency of inhibition differed (Pol-si2>siIVa2_2>siE1A_4). Double or triple combinations of the siRNAs compared with single siRNAs did not result in a measurably higher suppression of Ad replication. Combination of the siRNAs (alone or mixes of two or three siRNAs) with sCAR-Fc markedly increased the suppression of adenoviral replication compared to the same siRNA treatment without sCAR-Fc. Moreover, the triple combination of a mix of all three siRNAs, sCAR-Fc and cidofovir was about 23-fold more efficient than the combination of siRNAs mix/sCAR-Fc and about 95-fold more efficient than the siRNA mix alone. These data demonstrate that co-treatment of cells with sCAR-Fc and cidofovir is suitable to increase the efficiency of anti-adenoviral siRNAs.
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Affiliation(s)
- Tanja Pozzuto
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355 Berlin, Germany
| | - Carsten Röger
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355 Berlin, Germany
| | - Jens Kurreck
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355 Berlin, Germany
| | - Henry Fechner
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355 Berlin, Germany.
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30
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Interaction of human tumor viruses with host cell surface receptors and cell entry. Viruses 2015; 7:2592-617. [PMID: 26008702 PMCID: PMC4452921 DOI: 10.3390/v7052592] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 05/12/2015] [Indexed: 02/06/2023] Open
Abstract
Currently, seven viruses, namely Epstein-Barr virus (EBV), Kaposi's sarcoma-associated herpes virus (KSHV), high-risk human papillomaviruses (HPVs), Merkel cell polyomavirus (MCPyV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human T cell lymphotropic virus type 1 (HTLV-1), have been described to be consistently associated with different types of human cancer. These oncogenic viruses belong to distinct viral families, display diverse cell tropism and cause different malignancies. A key to their pathogenicity is attachment to the host cell and entry in order to replicate and complete their life cycle. Interaction with the host cell during viral entry is characterized by a sequence of events, involving viral envelope and/or capsid molecules as well as cellular entry factors that are critical in target cell recognition, thereby determining cell tropism. Most oncogenic viruses initially attach to cell surface heparan sulfate proteoglycans, followed by conformational change and transfer of the viral particle to secondary high-affinity cell- and virus-specific receptors. This review summarizes the current knowledge of the host cell surface factors and molecular mechanisms underlying oncogenic virus binding and uptake by their cognate host cell(s) with the aim to provide a concise overview of potential target molecules for prevention and/or treatment of oncogenic virus infection.
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31
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Adaptive Mutations Enhance Assembly and Cell-to-Cell Transmission of a High-Titer Hepatitis C Virus Genotype 5a Core-NS2 JFH1-Based Recombinant. J Virol 2015; 89:7758-75. [PMID: 25995244 DOI: 10.1128/jvi.00039-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/08/2015] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Recombinant hepatitis C virus (HCV) clones propagated in human hepatoma cell cultures yield relatively low infectivity titers. Here, we adapted the JFH1-based Core-NS2 recombinant SA13/JFH1C3405G,A3696G (termed SA13/JFH1orig), of the poorly characterized genotype 5a, to Huh7.5 cells, yielding a virus with greatly improved spread kinetics and an infectivity titer of 6.7 log10 focus-forming units (FFU)/ml. We identified several putative adaptive amino acid changes. In head-to-head infections at fixed multiplicities of infection, one SA13/JFH1orig mutant termed SA13/JFH1Core-NS5B, containing 13 amino acid changes (R114W and V187A [Core]; V235L [E1]; T385P [E2]; L782V [p7]; Y900C [NS2]; N2034D, E2238G, V2252A, L2266P, and I2340T [NS5A]; A2500S and V2841A [NS5B]), displayed fitness comparable to that of the polyclonal high-titer adapted virus. Single-cycle virus production assays in CD81-deficient Huh7-derived cells demonstrated that these changes did not affect replication but increased HCV assembly and specific infectivity as early as 24 h posttransfection. Infectious coculture assays in Huh7.5 cells showed a significant increase in cell-to-cell transmission for SA13/JFH1Core-NS5B viruses as well as viruses with only p7 and nonstructural protein mutations. Interestingly, the E2 hypervariable region 1 (HVR1) mutation T385P caused (i) increased sensitivity to neutralizing patient IgG and human monoclonal antibodies AR3A and AR4A and (ii) increased accessibility of the CD81 binding site without affecting the usage of CD81 and SR-BI. We finally demonstrated that SA13/JFH1orig and SA13/JFH1Core-NS5B, with and without the E2 mutation T385P, displayed similar biophysical properties following iodixanol gradient ultracentrifugation. This study has implications for investigations requiring high virus concentrations, such as studies of HCV particle composition and development of whole-virus vaccine antigens. IMPORTANCE Hepatitis C virus (HCV) is a major global health care burden, affecting more than 150 million people worldwide. These individuals are at high risk of developing severe end-stage liver diseases. No vaccine exists. While it is possible to produce HCV particles resembling isolates of all HCV genotypes in human hepatoma cells (HCVcc), production efficacy varies. Thus, for several important studies, including vaccine development, in vitro systems enabling high-titer production of diverse HCV strains would be advantageous. Our study offers important functional data on how cell culture-adaptive mutations identified in genotype 5a JFH1-based HCVcc permit high-titer culture by affecting HCV genesis through increasing virus assembly and HCV fitness by enhancing the virus specific infectivity and cell-to-cell transmission ability, without influencing the biophysical particle properties. High-titer HCVcc like the one described in this study may be pivotal in future vaccine-related studies where large quantities of infectious HCV particles are necessary.
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32
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Dockendorff C, Faloon PW, Germain A, Yu M, Youngsaye W, Nag PP, Bennion M, Penman M, Nieland TJF, Dandapani S, Perez JR, Munoz B, Palmer MA, Schreiber SL, Krieger M. Discovery of bisamide-heterocycles as inhibitors of scavenger receptor BI (SR-BI)-mediated lipid uptake. Bioorg Med Chem Lett 2015; 25:2594-8. [PMID: 25958245 DOI: 10.1016/j.bmcl.2015.03.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 12/01/2022]
Abstract
A new series of potent inhibitors of cellular lipid uptake from HDL particles mediated by scavenger receptor, class B, type I (SR-BI) was identified. The series was identified via a high-throughput screen of the National Institutes of Health Molecular Libraries Small Molecule Repository (NIH MLSMR) that measured the transfer of the fluorescent lipid DiI from HDL particles to CHO cells overexpressing SR-BI. The series is characterized by a linear peptidomimetic scaffold with two adjacent amide groups, as well as an aryl-substituted heterocycle. Analogs of the initial hit were rapidly prepared via Ugi 4-component reaction, and select enantiopure compounds were prepared via a stepwise sequence. Structure-activity relationship (SAR) studies suggest an oxygenated arene is preferred at the western end of the molecule, as well as highly lipophilic substituents on the central and eastern nitrogens. Compound 5e, with (R)-stereochemistry at the central carbon, was designated as probe ML279. Mechanistic studies indicate that ML279 stabilizes the interaction of HDL particles with SR-BI, and its effect is reversible. It shows good potency (IC50=17 nM), is non-toxic, plasma stable, and has improved solubility over our alternative probe ML278.
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Affiliation(s)
- Chris Dockendorff
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Department of Chemistry, Marquette University, PO Box 1881, Milwaukee, WI 53201-1881, USA.
| | - Patrick W Faloon
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Andrew Germain
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Miao Yu
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Willmen Youngsaye
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Partha P Nag
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Melissa Bennion
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Marsha Penman
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Thomas J F Nieland
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Sivaraman Dandapani
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - José R Perez
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Benito Munoz
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Michelle A Palmer
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Stuart L Schreiber
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Monty Krieger
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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Dockendorff C, Faloon PW, Yu M, Youngsaye W, Penman M, Nieland TJF, Nag PP, Lewis TA, Pu J, Bennion M, Negri J, Paterson C, Lam G, Dandapani S, Perez JR, Munoz B, Palmer MA, Schreiber SL, Krieger M. Indolinyl-Thiazole Based Inhibitors of Scavenger Receptor-BI (SR-BI)-Mediated Lipid Transport. ACS Med Chem Lett 2015; 6:375-380. [PMID: 26478787 PMCID: PMC4599563 DOI: 10.1021/ml500154q] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 02/02/2015] [Indexed: 01/14/2023] Open
Abstract
![]()
A potent class of indolinyl-thiazole
based inhibitors of cellular
lipid uptake mediated by scavenger receptor, class B, type I (SR-BI)
was identified via a high-throughput screen of the National Institutes
of Health Molecular Libraries Small Molecule Repository (NIH MLSMR)
in an assay measuring the uptake of the fluorescent lipid DiI from
HDL particles. This class of compounds is represented by ML278 (17–11), a potent (average IC50 = 6 nM) and reversible inhibitor of lipid uptake via SR-BI. ML278
is a plasma-stable, noncytotoxic probe that exhibits moderate metabolic
stability, thus displaying improved properties for in vitro and in
vivo studies. Strikingly, ML278 and previously described inhibitors
of lipid transport share the property of increasing the binding of
HDL to SR-BI, rather than blocking it, suggesting there may be similarities
in their mechanisms of action.
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Affiliation(s)
- Chris Dockendorff
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
- Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201-1881, United States
| | - Patrick W. Faloon
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Miao Yu
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Willmen Youngsaye
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Marsha Penman
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Thomas J. F. Nieland
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Partha P. Nag
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Timothy A. Lewis
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Jun Pu
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Melissa Bennion
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Joseph Negri
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Conor Paterson
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Garrett Lam
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Sivaraman Dandapani
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - José R. Perez
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Benito Munoz
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Michelle A. Palmer
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Stuart L. Schreiber
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
- Howard Hughes Medical Institute, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Monty Krieger
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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Dockendorff C, Faloon PW, Pu J, Yu M, Johnston S, Bennion M, Penman M, Nieland TJF, Dandapani S, Perez JR, Munoz B, Palmer MA, Schreiber SL, Krieger M. Benzo-fused lactams from a diversity-oriented synthesis (DOS) library as inhibitors of scavenger receptor BI (SR-BI)-mediated lipid uptake. Bioorg Med Chem Lett 2015; 25:2100-5. [PMID: 25900219 DOI: 10.1016/j.bmcl.2015.03.073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 02/07/2023]
Abstract
We report a new series of 8-membered benzo-fused lactams that inhibit cellular lipid uptake from HDL particles mediated by Scavenger Receptor, Class B, Type I (SR-BI). The series was identified via a high-throughput screen of the National Institutes of Health Molecular Libraries Small Molecule Repository (NIH MLSMR), measuring the transfer of the fluorescent lipid DiI from HDL particles to CHO cells overexpressing SR-BI. The series is part of a previously reported diversity-oriented synthesis (DOS) library prepared via a build-couple-pair approach. Detailed structure-activity relationship (SAR) studies were performed with a selection of the original library, as well as additional analogs prepared via solution phase synthesis. These studies demonstrate that the orientation of the substituents on the aliphatic ring have a critical effect on activity. Additionally, a lipophilic group is required at the western end of the molecule, and a northern hydroxyl group and a southern sulfonamide substituent also proved to be optimal. Compound 2p was found to possess a superior combination of potency (av IC50=0.10μM) and solubility (79μM in PBS), and it was designated as probe ML312.
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Affiliation(s)
- Chris Dockendorff
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Department of Chemistry, Marquette University, PO Box 1881, Milwaukee, WI 53201-1881, USA.
| | - Patrick W Faloon
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Jun Pu
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Miao Yu
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Stephen Johnston
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Melissa Bennion
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Marsha Penman
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Thomas J F Nieland
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Sivaraman Dandapani
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - José R Perez
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Benito Munoz
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Michelle A Palmer
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Stuart L Schreiber
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Monty Krieger
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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35
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Monoclonal antibodies against extracellular domains of claudin-1 block hepatitis C virus infection in a mouse model. J Virol 2015; 89:4866-79. [PMID: 25673725 DOI: 10.1128/jvi.03676-14] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/09/2015] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Hepatitis C virus (HCV) entry into host cells is a complex process requiring multiple host factors, including claudin-1 (CLDN1). Safe and effective therapeutic entry inhibitors need to be developed. We isolated a human hepatic Huh7.5.1-derived cell mutant that is nonpermissive to HCV, and comparative microarray analysis showed that the mutant was CLDN1 defective. Four hybridomas were obtained, which produced monoclonal antibodies (MAbs) that interacted with the parental Huh7.5.1 cell but not with the CLDN1-defective mutant. All MAbs produced by these hybridomas specifically bound to human CLDN1 with a very high affinity and prevented HCV infection of Huh7.5.1 cells in a dose-dependent manner, without apparent cytotoxicity. Two selected MAbs also inhibited HCV infection of human liver-chimeric mice without significant adverse effects. CLDN1 may be a potential target to prevent HCV infection in vivo. Anti-CLDN1 MAbs may hence be promising candidates as novel anti-HCV agents. IMPORTANCE Safe and effective therapeutic entry inhibitors against hepatitis C virus (HCV) are very useful for combination therapies with other anti-HCV drugs, such as direct-acting antivirals. In this study, we first showed an effective strategy for developing functional monoclonal antibodies (MAbs) against extracellular domains of a multimembrane-spanning target protein, claudin-1 (CLDN1), by using parental cells expressing the intact target membrane protein and target-defective cells. The established MAbs against CLDN1, which had a very high affinity for intact CLDN1, efficiently inhibited in vitro and in vivo HCV infections. These anti-CLDN1 MAbs are promising leads for novel entry inhibitors against HCV.
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Foquet L, Hermsen CC, Verhoye L, van Gemert GJ, Cortese R, Nicosia A, Sauerwein RW, Leroux-Roels G, Meuleman P. Anti-CD81 but not anti-SR-BI blocks Plasmodium falciparum liver infection in a humanized mouse model. J Antimicrob Chemother 2015; 70:1784-7. [PMID: 25656410 DOI: 10.1093/jac/dkv019] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/12/2015] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVES Plasmodium falciparum sporozoites, deposited in the skin by infected Anopheles mosquitoes taking a blood meal, cross the endothelium of skin capillaries and travel to the liver where they traverse Kupffer cells and hepatocytes to finally invade a small number of the latter. In hepatocytes, sporozoites replicate, differentiate and give rise to large numbers of merozoites that are released into the bloodstream where they invade red blood cells, thus initiating the symptomatic blood stage. Using in vitro systems and rodent models, it has been shown that the hepatocyte receptors CD81 and scavenger receptor type B class I (SR-BI) play a pivotal role during sporozoite invasion. We wanted to evaluate whether these two entry factors are genuine drug targets for the prevention of P. falciparum infection in humans. METHODS Immunodeficient mice of which the liver is largely repopulated by human hepatocytes were treated with monoclonal antibodies blocking either CD81 or SR-BI 1 day prior to challenge with infected mosquitoes. P. falciparum infection of the liver was demonstrated using a qPCR assay. RESULTS In human liver chimeric mice, an antibody directed against CD81 completely blocked P. falciparum sporozoite invasion while SR-BI-specific monoclonal antibodies did not influence in vivo infection. CONCLUSIONS These observations confirm the role of CD81 in liver-stage malaria and question that of SR-BI. CD81 might be a valuable drug target for the prevention of malaria.
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Affiliation(s)
- Lander Foquet
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Cornelus C Hermsen
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Lieven Verhoye
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Geert-Jan van Gemert
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | | | - Alfredo Nicosia
- CEINGE, Via Comunale Margherita, 484-538, 80131 Naples, Italy Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Corso Umberto I, 80138 Naples, Italy
| | - Robert W Sauerwein
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Geert Leroux-Roels
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Philip Meuleman
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
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Abstract
During infection significant alterations in lipid metabolism and lipoprotein composition occur. Triglyceride and VLDL cholesterol levels increase, while reduced HDL cholesterol (HDL-C) and LDL cholesterol (LDL-C) levels are observed. More importantly, endotoxemia modulates HDL composition and size: phospholipids are reduced as well as apolipoprotein (apo) A-I, while serum amyloid A (SAA) and secretory phospholipase A2 (sPLA2) dramatically increase, and, although the total HDL particle number does not change, a significant decrease in the number of small- and medium-size particles is observed. Low HDL-C levels inversely correlate with the severity of septic disease and associate with an exaggerated systemic inflammatory response. HDL, as well as other plasma lipoproteins, can bind and neutralize Gram-negative bacterial lipopolysaccharide (LPS) and Gram-positive bacterial lipoteichoic acid (LTA), thus favoring the clearance of these products. HDLs are emerging also as a relevant player during parasitic infections, and a specific component of HDL, namely, apoL-1, confers innate immunity against trypanosome by favoring lysosomal swelling which kills the parasite. During virus infections, proteins associated with the modulation of cholesterol bioavailability in the lipid rafts such as ABCA1 and SR-BI have been shown to favor virus entry into the cells. Pharmacological studies support the benefit of recombinant HDL or apoA-I mimetics during bacterial infection, while apoL-1-nanobody complexes were tested for trypanosome infection. Finally, SR-BI antagonism represents a novel and forefront approach interfering with hepatitis C virus entry which is currently tested in clinical studies. From the coming years, we have to expect new and compelling observations further linking HDL to innate immunity and infections.
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The mechanism of HCV entry into host cells. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 129:63-107. [PMID: 25595801 DOI: 10.1016/bs.pmbts.2014.10.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatitis C virus (HCV) is an enveloped, positive strand RNA virus classified within the Flaviviridae family and is a major cause of liver disease worldwide. HCV life cycle and propagation are tightly linked to several aspects of lipid metabolism. HCV propagation depends on and also shapes several aspects of lipid metabolism such as cholesterol uptake and efflux through different lipoprotein receptors during its entry into cells, lipid metabolism modulating HCV genome replication, lipid droplets acting as a platform for recruitment of viral components, and very low density lipoprotein assembly pathway resulting in incorporation of neutral lipids and apolipoproteins into viral particles. During the first steps of infection, HCV enters hepatocytes through a multistep and slow process. The initial capture of HCV particles by glycosaminoglycans and/or lipoprotein receptors is followed by coordinated interactions with the scavenger receptor class B type I, a major receptor of high-density lipoprotein, the CD81 tetraspanin, and the tight junction proteins Claudin-1 and Occludin. This tight concert of receptor interactions ultimately leads to uptake and cellular internalization of HCV through a process of clathrin-dependent endocytosis. Over the years, the identification of the HCV entry receptors and cofactors has led to a better understanding of HCV entry and of the narrow tropism of HCV for the liver. Yet, the role of the two HCV envelope glycoproteins, E1 and E2, remains ill-defined, particularly concerning their involvement in the membrane fusion process. Here, we review the current knowledge and advances addressing the mechanism of HCV cell entry within hepatocytes and we highlight the challenges that remain to be addressed.
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Vercauteren K, Mesalam AA, Leroux-Roels G, Meuleman P. Impact of lipids and lipoproteins on hepatitis C virus infection and virus neutralization. World J Gastroenterol 2014; 20:15975-91. [PMID: 25473151 PMCID: PMC4239485 DOI: 10.3748/wjg.v20.i43.15975] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/09/2014] [Accepted: 09/05/2014] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) infections represent a major global health problem. End-stage liver disease caused by chronic HCV infection is a major indication for liver transplantation. However, after transplantation the engrafted liver inevitably becomes infected by the circulating virus. Direct acting antivirals are not yet approved for use in liver transplant patients, and limited efficacy and severe side effects hamper the use of pegylated interferon combined with ribavirin in a post-transplant setting. Therefore, alternative therapeutic options need to be explored. Viral entry represents an attractive target for such therapeutic intervention. Understanding the mechanisms of viral entry is essential to define the viral and cellular factors involved. The HCV life cycle is dependent of and associated with lipoprotein physiology and the presence of lipoproteins has been correlated with altered antiviral efficacy of entry inhibitors. In this review, we summarise the current knowledge on how lipoprotein physiology influences the HCV life cycle. We focus especially on the influence of lipoproteins on antibodies that target HCV envelope proteins or antibodies that target the cellular receptors of the virus. This information can be particularly relevant for the prevention of HCV re-infection after liver transplantation.
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40
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Silencing of the scavenger receptor (Class B – Type 1) gene using siRNA-loaded chitosan nanaoparticles in a HepG2 cell model. Colloids Surf B Biointerfaces 2014; 123:930-7. [DOI: 10.1016/j.colsurfb.2014.10.045] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/14/2014] [Accepted: 10/22/2014] [Indexed: 11/22/2022]
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Vercauteren K, Van Den Eede N, Mesalam AA, Belouzard S, Catanese MT, Bankwitz D, Wong-Staal F, Cortese R, Dubuisson J, Rice CM, Pietschmann T, Leroux-Roels G, Nicosia A, Meuleman P. Successful anti-scavenger receptor class B type I (SR-BI) monoclonal antibody therapy in humanized mice after challenge with HCV variants with in vitro resistance to SR-BI-targeting agents. Hepatology 2014; 60:1508-18. [PMID: 24797654 PMCID: PMC4211977 DOI: 10.1002/hep.27196] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 04/29/2014] [Indexed: 02/06/2023]
Abstract
UNLABELLED Hepatitis C virus (HCV)-induced endstage liver disease is currently a major indication for liver transplantation. After transplantation the donor liver inevitably becomes infected with the circulating virus. Monoclonal antibodies (mAbs) against the HCV coreceptor scavenger receptor class B type I (SR-BI) inhibit HCV infection of different genotypes, both in cell culture and in humanized mice. Anti-SR-BI mAb therapy is successful even when initiated several days after HCV exposure, supporting its potential applicability to prevent HCV reinfection of liver allografts. However, HCV variants with reduced SR-BI dependency have been described in the literature, which could potentially limit the use of SR-BI targeting therapy. In this study we show, both in a preventative and postexposure setting, that humanized mice infected with HCV variants exhibiting increased in vitro resistance to SR-BI-targeting molecules remain responsive to anti-SR-BI mAb therapy in vivo. A 2-week antibody therapy readily cleared HCV RNA from the circulation of infected humanized mice. We found no evidence supporting increased SR-BI-receptor dependency of viral particles isolated from humanized mice compared to cell culture-produced virus. However, we observed that, unlike wild-type virus, the in vitro infectivity of the resistant variants was inhibited by both human high density lipoprotein (HDL) and very low density lipoprotein (VLDL). The combination of mAb1671 with these lipoproteins further increased the antiviral effect. CONCLUSION HCV variants that are less dependent on SR-BI in vitro can still be efficiently blocked by an anti-SR-BI mAb in humanized mice. Since these variants are also more susceptible to neutralization by anti-HCV envelope antibodies, their chance of emerging during anti-SR-BI therapy is severely reduced. Our data indicate that anti-SR-BI receptor therapy could be an effective way to prevent HCV infection in a liver transplant setting.
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Affiliation(s)
- Koen Vercauteren
- Department of Clinical Chemistry, Microbiology and Immunology, CEVAC, Gent, Belgium
| | - Naomi Van Den Eede
- Department of Clinical Chemistry, Microbiology and Immunology, CEVAC, Gent, Belgium
| | - Ahmed Atef Mesalam
- Department of Clinical Chemistry, Microbiology and Immunology, CEVAC, Gent, Belgium
| | - Sandrine Belouzard
- Institut Pasteur de Lille, Center for Infection & Immunity of Lille, Inserm U1019, CNRS UMR8204, Université Lille Nord de France
| | - Maria Teresa Catanese
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, USA,Department of Infectious Diseases, King’s College London School of Medicine, Guy’s Hospital, London SE1 9RT, United Kingdom
| | - Dorothea Bankwitz
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | | | | | - Jean Dubuisson
- Institut Pasteur de Lille, Center for Infection & Immunity of Lille, Inserm U1019, CNRS UMR8204, Université Lille Nord de France
| | - Charles M. Rice
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, USA
| | - 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 Centre for Infection Research (HZI), Hannover, Germany
| | - Geert Leroux-Roels
- Department of Clinical Chemistry, Microbiology and Immunology, CEVAC, Gent, Belgium
| | - Alfredo Nicosia
- CEINGE, via Gaetano Salvatore 486, 80145, Naples, Italy,Department of Molecular Medicine and Medical Biotechnology, University of Naples Frederico II, Naples, Italy
| | - Philip Meuleman
- Department of Clinical Chemistry, Microbiology and Immunology, CEVAC, Gent, Belgium,Corresponding author: Prof. Dr. Philip Meuleman, Center for Vaccinology – Ghent University, UZ Gent, Building A, 1st floor, De Pintelaan 185, B-9000 Gent, Belgium., Phone: +32 9 332 02 05, Fax: +32 9 332 63 11,
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Drummer HE. Antibodies to the high-density lipoprotein receptor SR-B1 potently inhibit hepatitis C virus replication in vivo: New avenues for preventing reinfection of the liver following transplantation. Hepatology 2014; 60:1463-5. [PMID: 24962233 PMCID: PMC4232903 DOI: 10.1002/hep.27276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 06/17/2014] [Indexed: 12/28/2022]
Affiliation(s)
- Heidi E Drummer
- Viral Fusion Laboratory, Centre for Biomedical Research, Burnet InstituteMelbourne, Australia,Department of Microbiology, Monash UniversityClayton, Australia,Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and ImmunityParkville, Australia.
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43
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Role of hypervariable region 1 for the interplay of hepatitis C virus with entry factors and lipoproteins. J Virol 2014; 88:12644-55. [PMID: 25142595 DOI: 10.1128/jvi.01145-14] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED Hepatitis C virus (HCV) particles associate with lipoproteins and infect cells by using at least four cell entry factors. These factors include scavenger receptor class B type I (SR-BI), CD81, claudin 1 (CLDN1), and occludin (OCLN). Little is known about specific functions of individual host factors during HCV cell entry and viral domains that mediate interactions with these factors. Hypervariable region 1 (HVR1) within viral envelope protein 2 (E2) is involved in the usage of SR-BI and conceals the viral CD81 binding site. Moreover, deletion of this domain alters the density of virions. We compared lipoprotein interaction, surface attachment, receptor usage, and cell entry between wild-type HCV and a viral mutant lacking this domain. Deletion of HVR1 did not affect CD81, CLDN1, and OCLN usage. However, unlike wild-type HCV, HVR1-deleted viruses were not neutralized by antibodies and small molecules targeting SR-BI. Nevertheless, modulation of SR-BI cell surface expression altered the infection efficiencies of both viruses to similar levels. Analysis of affinity-purified virions revealed comparable levels of apolipoprotein E (ApoE) incorporation into viruses with or without HVR1. However, ApoE incorporated into these viruses was differentially recognized by ApoE-specific antibodies. Thus, SR-BI has at least two functions during cell entry. One of them can be neutralized by SR-BI-targeting molecules, and it is critical only for wild-type HCV. The other one is important for both viruses but apparently is not inactivated by the SR-BI binding antibodies and small molecules evaluated here. In addition, HVR1 modulates the conformation and/or epitope exposure of virus particle-associated ApoE. IMPORTANCE HCV cell entry is SR-BI dependent irrespective of the presence or absence of HVR1. Moreover, this domain modulates the properties of ApoE on the surface of virus particles. These findings have implications for the development of SR-BI-targeting antivirals. Furthermore, these findings highlight separable functions of SR-BI during HCV cell entry and reveal a novel role of HVR1 for the properties of virus-associated lipoproteins.
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Shen WJ, Hu J, Hu Z, Kraemer FB, Azhar S. Scavenger receptor class B type I (SR-BI): a versatile receptor with multiple functions and actions. Metabolism 2014; 63:875-86. [PMID: 24854385 PMCID: PMC8078058 DOI: 10.1016/j.metabol.2014.03.011] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 03/12/2014] [Accepted: 03/18/2014] [Indexed: 11/16/2022]
Abstract
Scavenger receptor class B type I (SR-BI), is a physiologically relevant HDL receptor that mediates selective uptake of lipoprotein (HDL)-derived cholesteryl ester (CE) in vitro and in vivo. Mammalian SR-BI is a 509-amino acid, ~82 kDa glycoprotein that contains N- and C-terminal cytoplasmic domains, two-transmembrane domains, as well as a large extracellular domain containing 5-6 cysteine residues and multiple sites for N-linked glycosylation. The size and structural characteristics of SR-BI, however, vary considerably among lower vertebrates and insects. Recently, significant progress has been made in understanding the molecular mechanisms involved in the posttranscriptional/posttranslational regulation of SR-BI in a tissue specific manner. The purpose of this review is to summarize the current body of knowledge about the events and molecules connected with the posttranscriptional/posttranslational regulation of SR-BI and to update the molecular and functional characteristics of the insect SR-BI orthologs.
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MESH Headings
- Animals
- Biological Transport
- Gene Expression Regulation
- Glycosylation
- Humans
- Insect Proteins/chemistry
- Insect Proteins/genetics
- Insect Proteins/metabolism
- Lipoproteins, HDL/chemistry
- Lipoproteins, HDL/genetics
- Lipoproteins, HDL/metabolism
- Liver/metabolism
- Organ Specificity
- Protein Conformation
- Protein Processing, Post-Translational
- Receptors, Lipoprotein/chemistry
- Receptors, Lipoprotein/genetics
- Receptors, Lipoprotein/metabolism
- Scavenger Receptors, Class B/chemistry
- Scavenger Receptors, Class B/genetics
- Scavenger Receptors, Class B/metabolism
- Species Specificity
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Affiliation(s)
- Wen-Jun Shen
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Jie Hu
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304
| | - Zhigang Hu
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Fredric B Kraemer
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Endocrinology, Stanford University, Stanford, California 94305
| | - Salman Azhar
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, California 94304; Division of Gastroenterology and Hepatology, Stanford University, Stanford, California 94305.
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Abstract
High-density lipoproteins (HDL) are a target for drug development because of their proposed anti-atherogenic properties. In this review, we will briefly discuss the currently established drugs for increasing HDL-C, namely niacin and fibrates, and some of their limitations. Next, we will focus on novel alternative therapies that are currently being developed for raising HDL-C, such as CETP inhibitors. Finally, we will conclude with a review of novel drugs that are being developed for modulating the function of HDL based on HDL mimetics. Gaps in our knowledge and the challenges that will have to be overcome for these new HDL based therapies will also be discussed.
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Affiliation(s)
- Alan T Remaley
- National Heart, Lung and Blood Institute, NIH, 10 Center Drive, Bldg. 10, Rm. 2C-433, Bethesda, MD, USA
| | - Giuseppe D Norata
- Department of Pharmacological Sciences, Università degli Studi di Milano, Milano, Italy Center for the Study of Atherosclerosis, Società Italiana Studio Aterosclerosi, Ospedale Bassini, Cinisello Balsamo, Italy The Blizard Institute, Centre for Diabetes, Barts and The London School of Medicine & Dentistry, Queen Mary University, London, UK
| | - Alberico L Catapano
- Department of Pharmacological Sciences, Università degli Studi di Milano, Milano, Italy IRCCS Multimedica, Milan, Italy
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Mathiesen CK, Jensen TB, Prentoe J, Krarup H, Nicosia A, Law M, Bukh J, Gottwein JM. Production and characterization of high-titer serum-free cell culture grown hepatitis C virus particles of genotype 1-6. Virology 2014; 458-459:190-208. [PMID: 24928051 DOI: 10.1016/j.virol.2014.03.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 03/16/2014] [Accepted: 03/20/2014] [Indexed: 12/18/2022]
Abstract
Recently, cell culture systems producing hepatitis C virus particles (HCVcc) were developed. Establishment of serum-free culture conditions is expected to facilitate development of a whole-virus inactivated HCV vaccine. We describe generation of genotype 1-6 serum-free HCVcc (sf-HCVcc) from Huh7.5 hepatoma cells cultured in adenovirus expression medium. Compared to HCVcc, sf-HCVcc showed 0.6-2.1 log10 higher infectivity titers (4.7-6.2 log10 Focus Forming Units/mL), possibly due to increased release and specific infectivity of sf-HCVcc. In contrast to HCVcc, sf-HCVcc had a homogeneous single-peak density profile. Entry of sf-HCVcc depended on HCV co-receptors CD81, LDLr, and SR-BI, and clathrin-mediated endocytosis. HCVcc and sf-HCVcc were neutralized similarly by chronic-phase patient sera and by human monoclonal antibodies targeting conformational epitopes. Thus, we developed serum-free culture systems producing high-titer single-density sf-HCVcc, showing similar biological properties as HCVcc. This methodology has the potential to advance HCV vaccine development and to facilitate biophysical studies of HCV.
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Affiliation(s)
- Christian K Mathiesen
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Tanja B Jensen
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Jannick Prentoe
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Henrik Krarup
- Department of Clinical Biochemistry, Section of Molecular Diagnostics, Aalborg University Hospital, Fredrik Bajers Vej 5, 9220 Aalborg, Denmark
| | - Alfredo Nicosia
- CEINGE, Via Gaetano Salvatore, 486, 80145 Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, via S. Pansini 5, 80131, Naples, Italy; Okairos, viale Citta' d' Europa 279, 00144, Rome, Italy
| | - Mansun Law
- Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Judith M Gottwein
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
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47
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Abstract
PURPOSE OF REVIEW To summarize the recent findings about the roles of scavenger receptor class B type I (SR-BI) in immunity and discuss the underlying mechanisms by which SR-BI prevents immune dysfunctions. RECENT FINDINGS SR-BI is well known as a high-density lipoprotein (HDL) receptor playing key roles in HDL metabolism and in protection against atherosclerosis. Recent studies have indicated that SR-BI is also an essential modulator in immunity. SR-BI deficiency in mice causes immune dysfunctions, including increased atherosclerosis, elevated susceptibility to sepsis, impaired lymphocyte homeostasis, and autoimmune disorders. SR-BI exerts its protective roles through a variety of HDL-dependent and HDL-independent mechanisms. SR-BI is also involved in hepatitis C virus cell entry. A deficiency of SR-BI in humanized mice has been shown to decrease hepatitis C virus infectivity. SUMMARY SR-BI regulates immunity via multiple mechanisms and its deficiency causes numerous diseases. A comprehensive understanding of the roles of SR-BI in protection against immune dysfunctions may provide a therapeutic target for intervention against its associated diseases.
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Affiliation(s)
- Zhong Zheng
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Graduate Center for Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Junting Ai
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Graduate Center for Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Xiang-An Li
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Graduate Center for Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Saha Cardiovascular Research Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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48
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Fénéant L, Levy S, Cocquerel L. CD81 and hepatitis C virus (HCV) infection. Viruses 2014; 6:535-72. [PMID: 24509809 PMCID: PMC3939471 DOI: 10.3390/v6020535] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 01/29/2014] [Accepted: 02/02/2014] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C Virus (HCV) infection is a global public health problem affecting over 160 million individuals worldwide. Its symptoms include chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. HCV is an enveloped RNA virus mainly targeting liver cells and for which the initiation of infection occurs through a complex multistep process involving a series of specific cellular entry factors. This process is likely mediated through the formation of a tightly orchestrated complex of HCV entry factors at the plasma membrane. Among HCV entry factors, the tetraspanin CD81 is one of the best characterized and it is undoubtedly a key player in the HCV lifecycle. In this review, we detail the current knowledge on the involvement of CD81 in the HCV lifecycle, as well as in the immune response to HCV infection.
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Affiliation(s)
- Lucie Fénéant
- Center for Infection and Immunity of Lille, CNRS-UMR8204, Inserm-U1019, Institut Pasteur de Lille, Université Lille Nord de France, Institut de Biologie de Lille, 1 rue du Pr Calmette, CS50447, 59021 Lille Cedex, France.
| | - Shoshana Levy
- Department of Medicine, Division of Oncology, CCSR, Stanford University Medical Center, Stanford, CA 94305, USA.
| | - Laurence Cocquerel
- Center for Infection and Immunity of Lille, CNRS-UMR8204, Inserm-U1019, Institut Pasteur de Lille, Université Lille Nord de France, Institut de Biologie de Lille, 1 rue du Pr Calmette, CS50447, 59021 Lille Cedex, France.
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Abstract
Hepatitis C virus (HCV) is a hepatotropic virus and a major cause of chronic hepatitis and liver disease worldwide. Initial interactions between HCV virions and hepatocytes are required for productive viral infection and initiation of the viral life cycle. Furthermore, HCV entry contributes to the tissue tropism and species specificity of this virus. The elucidation of these interactions is critical, not only to understand the pathogenesis of HCV infection, but also to design efficient antiviral strategies and vaccines. This review summarizes our current knowledge of the host factors required for the HCV-host interactions during HCV binding and entry, our understanding of the molecular mechanisms underlying HCV entry into target cells, and the relevance of HCV entry for the pathogenesis of liver disease, antiviral therapy, and vaccine development.
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Cell-cell contact-mediated hepatitis C virus (HCV) transfer, productive infection, and replication and their requirement for HCV receptors. J Virol 2013; 87:8545-58. [PMID: 23720720 DOI: 10.1128/jvi.01062-13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Hepatitis C virus (HCV) infection is believed to begin with interactions between cell-free HCV and cell receptors that include CD81, scavenger receptor B1 (SR-B1), claudin-1 (CLDN1), and occludin (OCLN). In this study, we have demonstrated that HCV spreading from infected hepatocytes to uninfected hepatocytes leads to the transfer of HCV and the formation of infection foci and is cell density dependent. This cell-cell contact-mediated (CCCM) HCV transfer occurs readily and requires all these known HCV receptors and an intact actin cytoskeleton. With a fluorescently labeled replication-competent HCV system, the CCCM transfer process was further dissected by live-cell imaging into four steps: donor cell-target cell contact, formation of viral puncta-target cell conjugation, transfer of viral puncta, and posttransfer. Importantly, the CCCM HCV transfer leads to productive infection of target cells. Taken together, these results show that CCCM HCV transfer constitutes an important and effective route for HCV infection and dissemination. These findings will aid in the development of new and novel strategies for preventing and treating HCV infection.
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