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Adugna A. Therapeutic strategies and promising vaccine for hepatitis C virus infection. Immun Inflamm Dis 2023; 11:e977. [PMID: 37647422 PMCID: PMC10461427 DOI: 10.1002/iid3.977] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 07/22/2023] [Accepted: 07/30/2023] [Indexed: 09/01/2023] Open
Abstract
Hepatitis C virus (HCV) infection is still a significant global health problem despite therapeutic advancements. Ribavirin and interferon therapy have been the sole available treatments for HCV infection for a number of years with low efficacy. Thus, currently, a number of therapeutic strategies are being used, including nanoparticles (NPs), micro-RNAs such as small interfering RNA (siRNA), RNAi-based gene silencing and antisense oligonucleotide-based microRNA-122, microRNA-155, and short hairpin RNAs (shRNAs), and immunotherapeutic approaches such as anti-programmed cell death 1(PD-1), monoclonal antibodies (mAb or moAb), and monocyte-derived dendritic cells (Mo-DCs). Furthermore, direct-acting antivirals (DAAs) and host-targeting agents (HTA) were also the current therapeutic approaches with great efficacy. In spite of different clinical trials on HCV vaccine developments, nowadays there is no effective HCV vaccine in opposition to virus due to various challenges including genetic diversity, lack of immunocompetent small animal models, shortage of HCV vaccination testing alternatives, lack of an effective tissue culture method for replicating HCV, and inadequate knowledge regarding to immune responses against HCV infection. Nowadays, mRNA vaccine, recombinant viral vector, peptides vaccine, virus-like particles, DNA vaccine, rational designed vaccine, and recombinant polyantigenic T-cell-based vaccine are novel promising candidates for HCV vaccine based on various clinical trials. This review summarizes the different therapeutic approaches and the advancements of vaccine candidates for HCV infection.
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Affiliation(s)
- Adane Adugna
- Medical Microbiology, Medical Laboratory Sciences, College of Health SciencesDebre Markos UniversityDebre MarkosEthiopia
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2
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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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Tarannum H, Chauhan B, Samadder A, Roy H, Nandi S. To Explore the Potential Targets and Current Structure-based Design Strategies Utilizing Co-crystallized Ligand to Combat HCV. Curr Drug Targets 2021; 22:590-604. [PMID: 32720601 DOI: 10.2174/1389450121999200727215020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/05/2020] [Accepted: 05/11/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Hepatitis C Virus (HCV) belongs to the Hepacivirus family. HCV has been designated as a very dreadful virus as it can attack the liver, causing inflammation and even may lead to cancer in chronic conditions. It was estimated that 71 million people around the world have chronic HCV infection. World Health Organization (WHO) reported that about 399000 people died because of chronic cirrhosis and liver cancer globally. In spite of the abundance of availability of drugs for the treatment of HCV, however, the issue of drug resistance surpasses all the possibilities of therapeutic management of HCV. Therefore, to address this issue of 'drug-resistance', various HCV targets were explored to quest the evaluation of the mechanism of the disease progression. METHODS An attempt has been made in the present study to explore the various targets of HCV involved in the mechanism(s) of the disease initiation and progression and to focus on the mode of binding of ligands, which are co-crystallized at the active cavity of different HCV targets. CONCLUSION The present study could predict some crucial features of these ligands, which possibly interacted with various amino acid residues responsible for their biological activity and molecular signaling pathway(s). Such binding mode may be considered as a template for the high throughput screening and designing of active congeneric ligands to combat HCV.
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Affiliation(s)
- Heena Tarannum
- Department of Pharmaceutical Chemistry, Global Institute of Pharmaceutical Education and Research (Affiliated to Uttarakhand Technical University), Kashipur-244713, India
| | - Bhumika Chauhan
- Department of Pharmaceutical Chemistry, Global Institute of Pharmaceutical Education and Research (Affiliated to Uttarakhand Technical University), Kashipur-244713, India
| | - Asmita Samadder
- Cytogenetics and Molecular Biology Lab., Department of Zoology, University of Kalyani, Kalyani, Nadia, 741235, India
| | - Harekrishna Roy
- Nirmala College of Pharmacy, Mangalagiri, Guntur, Andhra Pradesh, 522503, India
| | - Sisir Nandi
- Department of Pharmaceutical Chemistry, Global Institute of Pharmaceutical Education and Research (Affiliated to Uttarakhand Technical University), Kashipur-244713, India
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Liao Y, Luo D, Peng K, Zeng Y. Cyclophilin A: a key player for etiological agent infection. Appl Microbiol Biotechnol 2021; 105:1365-1377. [PMID: 33492451 PMCID: PMC7829623 DOI: 10.1007/s00253-021-11115-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 01/07/2021] [Accepted: 01/13/2021] [Indexed: 12/13/2022]
Abstract
Abstract Cyclophilin A (CypA), a key member of the immunophilin family, is the most abundantly expressed isozyme of the 18 known human cyclophilins. Besides acting as an intracellular receptor for cyclosporine A, CypA plays a vital role in microorganismal infections, cardiovascular diseases, liver diseases, kidney diseases, neurodegeneration, cancer, rheumatoid arthritis, periodontitis, sepsis, asthma, and aging. This review focuses on the pivotal roles of CypA in the infection of etiological agents, which manifests mainly in promoting or inhibiting viral replication based on the host cell type and viral species. CypA can interact with viral proteins and thus regulate the replication cycle of the virus. CypA is involved in pathogenic bacterial infections by regulating the formation of host actin skeleton or membrane translocation of bacterial toxins, or mediated the adhesion of Mycoplasma genitalium during the infection processes by acting as a cellular receptor of M. genitalium. CypA also plays a critical role in infection or the life cycle of certain parasites or host immune regulation. Moreover, we summarized the current understanding of CypA inhibitors acting as host-targeting antiviral agents, thus opening an avenue for the treatment of multiple viral infections due to their broad antiviral effects and ability to effectively prevent drug resistance. Therefore, the antiviral effect of CypA has the potential to promote CypA inhibitors as host-targeting drugs to CypA-involved etiological agent infections and human diseases. Key points • CypA is involved in the replication and infection of several viruses, pathogenic bacteria, mycoplasma, and parasites. • CypA inhibitors are in a strong position to inhibit the infection of viruses, bacterial, and mycoplasma.
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Affiliation(s)
- Yating Liao
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Dan Luo
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Kailan Peng
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Yanhua Zeng
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
- Department of Dermatology and Venereology, The First Affiliated Hospital, University of South China, Hengyang City, 421001 Hunan Province People’s Republic of China
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Neufeldt CJ, Cortese M, Acosta EG, Bartenschlager R. Rewiring cellular networks by members of the Flaviviridae family. Nat Rev Microbiol 2019; 16:125-142. [PMID: 29430005 PMCID: PMC7097628 DOI: 10.1038/nrmicro.2017.170] [Citation(s) in RCA: 230] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Members of the Flaviviridae virus family comprise a large group of enveloped viruses with a single-strand RNA genome of positive polarity. Several genera belong to this family, including the Hepacivirus genus, of which hepatitis C virus (HCV) is the prototype member, and the Flavivirus genus, which contains both dengue virus and Zika virus. Viruses of these genera differ in many respects, such as the mode of transmission or the course of infection, which is either predominantly persistent in the case of HCV or acutely self-limiting in the case of flaviviruses. Although the fundamental replication strategy of Flaviviridae members is similar, during the past few years, important differences have been discovered, including the way in which these viruses exploit cellular resources to facilitate viral propagation. These differences might be responsible, at least in part, for the various biological properties of these viruses, thus offering the possibility to learn from comparisons. In this Review, we discuss the current understanding of how Flaviviridae viruses manipulate and usurp cellular pathways in infected cells. Specifically, we focus on comparing strategies employed by flaviviruses with those employed by hepaciviruses, and we discuss the importance of these interactions in the context of viral replication and antiviral therapies.
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Affiliation(s)
- Christopher J Neufeldt
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Eliana G Acosta
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany.,German Center for Infection Research, Heidelberg Partner Site, 69120 Heidelberg, Germany
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Gallay P, Ure D, Bobardt M, Chatterji U, Ou J, Trepanier D, Foster R. The cyclophilin inhibitor CRV431 inhibits liver HBV DNA and HBsAg in transgenic mice. PLoS One 2019; 14:e0217433. [PMID: 31181107 PMCID: PMC6557616 DOI: 10.1371/journal.pone.0217433] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/10/2019] [Indexed: 02/07/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a major health burden worldwide with 240 million chronically infected individuals. Nucleos(t)ide analogs and interferons are the current standards of care due to their suppression of HBV replication, but the treatments rarely eradicate HBV from individuals. Similar to current treatments for human immunodeficiency virus type-1 (HIV-1) and hepatitis C virus (HCV) patients, improved HBV therapies will require the combination of multiple drugs which target distinct steps of the HBV life cycle. In this study, we tested the potential of a cyclophilin inhibitor, CRV431, to affect HBV replication in transgenic mice. We found that oral treatment with CRV431 (50 mg/kg/day) for a period of 16 days significantly reduced liver HBV DNA levels and moderately decreased serum HBsAg levels. We observed an additive inhibitory effect on liver HBV DNA levels in mice treated with a combination of low doses of CRV431 (10 mg/kg/day) and the nucleotide prodrug, tenofovir exalidex (TXL), (5 mg/kg/day). No toxicity was observed in CRV431-treated mice. Although it is well known that CRV431 neutralizes the peptidyl-prolyl isomerase activity of cyclophilins, its anti-HBV mechanism(s) of action remains unknown. Nevertheless, this study provides the first demonstration of a beneficial effect of a cyclophilin inhibitor in vivo in an HBV transgenic mouse model. Altogether our data reveal the potential of CRV431 to be part of improved new therapies for HBV patients.
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Affiliation(s)
- Philippe Gallay
- Department of Immunology & Microbiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Daren Ure
- ContraVir Pharmaceuticals Inc., Edison, New Jersey, United States of America
| | - Michael Bobardt
- Department of Immunology & Microbiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Udayan Chatterji
- Department of Immunology & Microbiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - James Ou
- Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California, United States of America
| | - Daniel Trepanier
- ContraVir Pharmaceuticals Inc., Edison, New Jersey, United States of America
| | - Robert Foster
- ContraVir Pharmaceuticals Inc., Edison, New Jersey, United States of America
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Crouchet E, Wrensch F, Schuster C, Zeisel MB, Baumert TF. Host-targeting therapies for hepatitis C virus infection: current developments and future applications. Therap Adv Gastroenterol 2018; 11:1756284818759483. [PMID: 29619090 PMCID: PMC5871046 DOI: 10.1177/1756284818759483] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/15/2018] [Indexed: 02/04/2023] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a leading cause of chronic liver diseases and hepatocellular carcinoma (HCC) worldwide. In the past few years, anti-HCV therapies have undergone a revolution with the approval of multiple direct-acting antivirals (DAAs), which enable interferon-free treatments with considerable improvement of sustained virologic response in patients. Today, DAAs have become the standard of care for HCV therapy. However, several limitations remain, which include access to therapy, treatment failure in a subset of patients and persistent risk of HCC development following cure in patients with advanced fibrosis. By targeting conserved host proteins involved in the HCV life cycle, host-targeting agents (HTAs) offer opportunities for pan-genotypic antiviral approaches with a high barrier to drug resistance. Moreover, when applied in combination with DAAs, HTAs could improve the management of difficult-to-treat patients by acting through a complementary mechanism of action. In this review, we summarize the different HTAs evaluated in preclinical and clinical development and discuss their potential role for anti-HCV therapies.
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Affiliation(s)
- Emilie Crouchet
- Institut National de la Santé et de la Recherche Médicale (Inserm), U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France Université de Strasbourg, Strasbourg, France
| | - Florian Wrensch
- Institut National de la Santé et de la Recherche Médicale (Inserm), U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France Université de Strasbourg, Strasbourg, France
| | - Catherine Schuster
- Institut National de la Santé et de la Recherche Médicale (Inserm), U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France Université de Strasbourg, Strasbourg, France
| | - Mirjam B. Zeisel
- Institut National de la Santé et de la Recherche Médicale (Inserm), U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France Université de Strasbourg, Strasbourg, France Inserm U1052, CNRS UMR 5286, Cancer Research Center of Lyon (CRCL), Université de Lyon (UCBL), Lyon, France
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Zhang X, Lv X, Tang S, Mei L, Li Y, Zhang J, Jiang J, Peng Z, Song D. Discovery and evolution of aloperine derivatives as a new family of HCV inhibitors with novel mechanism. Eur J Med Chem 2018; 143:1053-1065. [DOI: 10.1016/j.ejmech.2017.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/30/2017] [Accepted: 12/01/2017] [Indexed: 12/23/2022]
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Tseng CH, Lin CK, Chen YL, Tseng CK, Lee JY, Lee JC. Discovery of naphtho[1,2-d]oxazole derivatives as potential anti-HCV agents through inducing heme oxygenase-1 expression. Eur J Med Chem 2018; 143:970-982. [DOI: 10.1016/j.ejmech.2017.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 11/30/2017] [Accepted: 12/02/2017] [Indexed: 01/05/2023]
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10
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Beilstein F, Lemasson M, Pène V, Rainteau D, Demignot S, Rosenberg AR. Lysophosphatidylcholine acyltransferase 1 is downregulated by hepatitis C virus: impact on production of lipo-viro-particles. Gut 2017; 66:2160-2169. [PMID: 27582510 DOI: 10.1136/gutjnl-2016-311508] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 08/02/2016] [Accepted: 08/08/2016] [Indexed: 12/18/2022]
Abstract
OBJECTIVE HCV is intimately linked with the liver lipid metabolism, devoted to the efflux of triacylglycerols stored in lipid droplets (LDs) in the form of triacylglycerol-rich very-low-density lipoproteins (VLDLs): (i) the most infectious HCV particles are those of lowest density due to association with triacylglycerol-rich lipoproteins and (ii) HCV-infected patients frequently develop hepatic steatosis (increased triacylglycerol storage). The recent identification of lysophosphatidylcholine acyltransferase 1 (LPCAT1) as an LD phospholipid-remodelling enzyme prompted us to investigate its role in liver lipid metabolism and HCV infectious cycle. DESIGN Huh-7.5.1 cells and primary human hepatocytes (PHHs) were infected with JFH1-HCV. LPCAT1 depletion was achieved by RNA interference. Cells were monitored for LPCAT1 expression, lipid metabolism and HCV production and infectivity. The density of viral particles was assessed by isopycnic ultracentrifugation. RESULTS Upon HCV infection, both Huh-7.5.1 cells and PHH had decreased levels of LPCAT1 transcript and protein, consistent with transcriptional downregulation. LPCAT1 depletion in either naive or infected Huh-7.5.1 cells resulted in altered lipid metabolism characterised by LD remodelling, increased triacylglycerol storage and increased secretion of VLDL. In infected Huh-7.5.1 cells or PHH, LPCAT1 depletion increased production of the viral particles of lowest density and highest infectivity. CONCLUSIONS We have identified LPCAT1 as a modulator of liver lipid metabolism downregulated by HCV, which appears as a viral strategy to increase the triacylglycerol content and hence infectivity of viral particles. Targeting this metabolic pathway may represent an attractive therapeutic approach to reduce both the viral titre and hepatic steatosis.
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Affiliation(s)
- Frauke Beilstein
- Sorbonne Universités, UPMC Univ. Paris 06, Inserm, Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,EPHE, Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Pharmacologie Cellulaire et Moléculaire, Paris, France
| | - Matthieu Lemasson
- Université Paris Descartes, EA 4474 «Hepatitis C Virology», Paris, France
| | - Véronique Pène
- Université Paris Descartes, EA 4474 «Hepatitis C Virology», Paris, France
| | | | - Sylvie Demignot
- Sorbonne Universités, UPMC Univ. Paris 06, Inserm, Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.,EPHE, Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Pharmacologie Cellulaire et Moléculaire, Paris, France
| | - Arielle R Rosenberg
- Université Paris Descartes, EA 4474 «Hepatitis C Virology», Paris, France.,AP-HP, Groupe Hospitalier Cochin, Service de Virologie, Paris, France
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Hu L, Li J, Cai H, Yao W, Xiao J, Li YP, Qiu X, Xia H, Peng T. Avasimibe: A novel hepatitis C virus inhibitor that targets the assembly of infectious viral particles. Antiviral Res 2017; 148:5-14. [PMID: 29074218 DOI: 10.1016/j.antiviral.2017.10.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/15/2017] [Accepted: 10/20/2017] [Indexed: 02/06/2023]
Abstract
Direct-acting antivirals (DAAs), which target hepatitis C virus (HCV) proteins, have exhibited impressive efficacy in the management of chronic hepatitis C. However, the concerns regarding high costs, drug resistance mutations and subsequent unexpected side effects still call for the development of host-targeting agents (HTAs) that target host factors involved in the viral life cycle and exhibit pan-genotypic antiviral activity. Given the close relationship between lipid metabolism and the HCV life cycle, we investigated the anti-HCV activity of a series of lipid-lowering drugs that have been approved by government administrations or proven safety in clinical trials. Our results showed that avasimibe, an inhibitor of acyl coenzyme A:cholesterol acyltransferase (ACAT), exhibited marked pan-genotypic inhibitory activity and superior inhibition against HCV when combined with DAAs. Moreover, avasimibe significantly impaired the assembly of infectious HCV virions. Mechanistic studies demonstrated that avasimibe induced downregulation of microsomal triglyceride transfer protein expression, resulting in reduced apolipoprotein E and apolipoprotein B secretion. Therefore, the pan-genotypic antiviral activity and clinically proven safety endow avasimibe exceptional potential as a candidate for combination therapy with DAAs. In addition, the discovery of the antiviral properties of ACAT inhibitors also suggests that inhibiting the synthesis of cholesteryl esters might be an additional target for the therapeutic intervention for chronic HCV infection.
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Affiliation(s)
- Longbo Hu
- Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China; State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, 511436, China
| | - Jinqian Li
- Institute of Human Virology and Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Hua Cai
- State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, 511436, China
| | - Wenxia Yao
- The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China
| | - Jing Xiao
- State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, 511436, China
| | - Yi-Ping Li
- Institute of Human Virology and Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Xiu Qiu
- Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China.
| | - Huimin Xia
- Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China; Department of Neonatal Surgery, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China.
| | - Tao Peng
- State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, 511436, China.
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Kulkarni MM, Ratcliff AN, Bhat M, Alwarawrah Y, Hughes P, Arcos J, Loiselle D, Torrelles JB, Funderburg NT, Haystead TA, Kwiek JJ. Cellular fatty acid synthase is required for late stages of HIV-1 replication. Retrovirology 2017; 14:45. [PMID: 28962653 PMCID: PMC5622536 DOI: 10.1186/s12977-017-0368-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 09/14/2017] [Indexed: 11/21/2022] Open
Abstract
Background
Like all viruses, HIV-1 relies on host systems to replicate. The human purinome consists of approximately two thousand proteins that bind and use purines such as ATP, NADH, and NADPH. By virtue of their purine binding pockets, purinome proteins are highly druggable, and many existing drugs target purine-using enzymes. Leveraging a protein affinity media that uses the purine-binding pocket to capture the entire purinome, we sought to define purine-binding proteins regulated by HIV-1 infection. Results Using purinome capture media, we observed that HIV-1 infection increases intracellular levels of fatty acid synthase (FASN), a NADPH-using enzyme critical to the synthesis of de novo fatty acids. siRNA mediated knockdown of FASN reduced HIV-1 particle production by 80%, and treatment of tissue culture cells or primary PBMCs with Fasnall, a newly described selective FASN inhibitor, reduced HIV-1 virion production by 90% (EC50 = 213 nM). Despite the requirement of FASN for nascent virion production, FASN activity was not required for intracellular Gag protein production, indicating that FASN dependent de novo fatty acid biosynthesis contributes to a late step of HIV-1 replication. Conclusions Here we show that HIV-1 replication both increases FASN levels and requires host FASN activity. We also report that Fasnall, a novel FASN inhibitor that demonstrates anti-tumor activity in vivo, is a potent and efficacious antiviral, blocking HIV-1 replication in both tissue culture and primary cell models of HIV-1 replication. In adults, most fatty acids are obtained exogenously from the diet, thus making FASN a plausible candidate for pharmacological intervention. In conclusion, we hypothesize that FASN is a novel host dependency factor and that inhibition of FASN activity has the potential to be exploited as an antiretroviral strategy.
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Affiliation(s)
- Manjusha M Kulkarni
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, The Ohio State University, Columbus, OH, USA
| | - Annette N Ratcliff
- Department of Microbiology, Center for Retrovirus Research, The Ohio State University, 476 Biological Sciences Building, 484 W. 12th Avenue, Columbus, OH, 43210, USA.,Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711-5399, USA
| | - Menakshi Bhat
- Department of Microbiology, Center for Retrovirus Research, The Ohio State University, 476 Biological Sciences Building, 484 W. 12th Avenue, Columbus, OH, 43210, USA
| | - Yazan Alwarawrah
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, C118 LSRC, Box 3813, Durham, NC, 27710, USA
| | - Philip Hughes
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, C118 LSRC, Box 3813, Durham, NC, 27710, USA
| | - Jesus Arcos
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, The Ohio State University, Columbus, OH, USA
| | - David Loiselle
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, C118 LSRC, Box 3813, Durham, NC, 27710, USA
| | - Jordi B Torrelles
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, The Ohio State University, Columbus, OH, USA.,Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Nicholas T Funderburg
- Division of Medical Laboratory Science, School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, USA
| | - Timothy A Haystead
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, C118 LSRC, Box 3813, Durham, NC, 27710, USA.
| | - Jesse J Kwiek
- Department of Microbiology, Center for Retrovirus Research, The Ohio State University, 476 Biological Sciences Building, 484 W. 12th Avenue, Columbus, OH, 43210, USA.
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Das S, Mullick R, Kumar A, Tandon H, Bose M, Gouthamchandra K, Chandra M, Ravishankar B, Khaja MN, Srinivasan N, Das S, Melkote Subbarao S, Karande AA. Identification of a novel epitope in the C terminus of hepatitis C virus-E2 protein that induces potent and cross-reactive neutralizing antibodies. J Gen Virol 2017; 98:962-976. [PMID: 28221101 DOI: 10.1099/jgv.0.000735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a leading cause of chronic viral hepatitis, but an effective vaccine is still not available to prevent infection. Use of neutralizing antibodies could be a potential therapeutic option. In this study, the presence of anti-HCV antibodies in HCV-infected patients was assessed from 50 patients and the presence of neutralizing antibodies was examined using 'hepatitis C virus-like particles'. Antibodies from two samples exhibited significant inhibitory activity, suggesting that these may neutralize viral infection. Antigenic determinants generating the neutralizing antibodies from these two samples were delineated by epitope mapping using the core, E1 and E2 regions and a stretch of 45 amino acid peptide (E2C45) derived from the C-terminal region of HCV-E2 protein (aa 634-679) was designed. Results suggest that this hitherto uncharacterized region has the potential to generate neutralizing antibodies against HCV and thus be effective in preventing virus entry into liver cells. Computational analysis of the structure of the modelled peptide (E2C45) suggested high conformational entropy for this region. Furthermore, E2C45 peptide-generated antibodies could block virus entry and monoclonal antibodies generated against this peptide could also significantly reduce virus replication in a cell culture system. It is possible that the inhibition could be partly due to a conformational alteration of the CD81-binding region, preventing virus attachment to liver cells. In conclusion, this work focused on the discovery of a novel epitope at the C terminus of E2 that induces potent neutralizing antibodies in HCV-infected patients.
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Affiliation(s)
- Soma Das
- Department of Biochemistry, Indian Institute of Science, Bangalore 560 012, India
| | - Ranajoy Mullick
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560 012, India
| | - Anuj Kumar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560 012, India
| | - Himani Tandon
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Mihika Bose
- Department of Biochemistry, Indian Institute of Science, Bangalore 560 012, India
| | - K Gouthamchandra
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560 012, India
| | - Madhavi Chandra
- Bioviz Technologies Pvt Ltd, Sagar Society, Road No. 2, Banjara Hills, Hyderabad 500 034, India
| | | | - M N Khaja
- Bioviz Technologies Pvt Ltd, Sagar Society, Road No. 2, Banjara Hills, Hyderabad 500 034, India
| | | | - Saumitra Das
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560 012, India
| | - Shaila Melkote Subbarao
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560 012, India
| | - Anjali Anoop Karande
- Department of Biochemistry, Indian Institute of Science, Bangalore 560 012, India
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14
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Hayes CN, Chayama K. Why highly effective drugs are not enough: the need for an affordable solution to eliminating HCV. Expert Rev Clin Pharmacol 2017; 10:583-594. [PMID: 28374641 DOI: 10.1080/17512433.2017.1313111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Because of the rapid pace of development of new direct-acting antiviral (DAA) drugs, chronic hepatitis C virus (HCV) infection is now increasingly considered curable. However, the emphasis on DAA therapies disregards key issues related to cost, availability, and antiviral resistance. Areas covered: This perspective provides an overview of current HCV therapies and the development of DAAs, followed by a discussion of the limitations of DAA therapy. A literature search was used to select relevant studies, and a web search for relevant news articles and press releases was conducted. Expert commentary: Despite cure rates exceeding 90%, now is not the time to declare victory against HCV but to reinforce recent progress by addressing the issues of cost and availability as well as by developing strategies to manage antiviral resistance. Future drug development efforts should place greater emphasis on targeting host factors required for HCV replication, for which the barrier to resistance is higher, and effort should continue to develop a vaccine against HCV. Finally, efforts should be made to facilitate large-scale screening in endemic areas to identify and treat patients as early as possible to reduce long-term risks of advanced liver disease and their attendant costs of management.
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Affiliation(s)
- C Nelson Hayes
- a Department of Gastroenterology and Metabolism, Applied Life Sciences, Institute of Biomedical and Health Sciences , Hiroshima University , Hiroshima , Japan.,b Liver Research Project Center , Hiroshima University , Hiroshima , Japan
| | - Kazuaki Chayama
- a Department of Gastroenterology and Metabolism, Applied Life Sciences, Institute of Biomedical and Health Sciences , Hiroshima University , Hiroshima , Japan.,b Liver Research Project Center , Hiroshima University , Hiroshima , Japan.,c Laboratory for Digestive Diseases, Center for Genomic Medicine , RIKEN , Hiroshima , Japan
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15
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Anti-hepatitis C virus strategy targeting host entry factor claudin-1. Uirusu 2017; 65:245-254. [PMID: 27760923 DOI: 10.2222/jsv.65.245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Chronic hepatitis C virus (HCV) infection is a major threat to global public health, because it is significantly correlated with the development of severe liver diseases including cirrhosis and hepatocellular carcinomas. Host molecules as well as viral factors are promising targets for anti-HCV preventive and therapeutic strategies. Multiple host factors such as CD81, SRBI, claudin-1, and occludin are involved in HCV entry into hepatocytes. In this paper, I first introduce our anti-HCV strategy targeting for host tight junction protein claudin-1. And this review also summarizes developments of other entry inhibitors to prevent initiation of HCV infection and spread. Entry inhibitors might be useful in blocking primary infections, such those as after liver transplantation, and in combination therapies with other anti-HCV agents such as direct-acting antivirals.
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16
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Chiang AWT, Wu WYL, Wang T, Hwang MJ. Identification of Entry Factors Involved in Hepatitis C Virus Infection Based on Host-Mimicking Short Linear Motifs. PLoS Comput Biol 2017; 13:e1005368. [PMID: 28129350 PMCID: PMC5302801 DOI: 10.1371/journal.pcbi.1005368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 02/10/2017] [Accepted: 01/17/2017] [Indexed: 12/15/2022] Open
Abstract
Host factors that facilitate viral entry into cells can, in principle, be identified from a virus-host protein interaction network, but for most viruses information for such a network is limited. To help fill this void, we developed a bioinformatics approach and applied it to hepatitis C virus (HCV) infection, which is a current concern for global health. Using this approach, we identified short linear sequence motifs, conserved in the envelope proteins of HCV (E1/E2), that potentially can bind human proteins present on the surface of hepatocytes so as to construct an HCV (envelope)-host protein interaction network. Gene Ontology functional and KEGG pathway analyses showed that the identified host proteins are enriched in cell entry and carcinogenesis functionalities. The validity of our results is supported by much published experimental data. Our general approach should be useful when developing antiviral agents, particularly those that target virus-host interactions. Viruses recruit host proteins, called entry factors, to help gain entry to host cells. Identification of entry factors can provide targets for developing antiviral drugs. By exploring the concept that short linear peptide motifs involved in human protein-protein interactions may be mimicked by viruses to hijack certain host cellular processes and thereby assist viral infection/survival, we developed a bioinformatics strategy to computationally identify entry factors of hepatitis C virus (HCV) infection, which is a worldwide health problem. Analysis of cellular functions and biochemical pathways indicated that the human proteins we identified usually play a role in cell entry and/or carcinogenesis, and results of the analysis are generally supported by experimental studies on HCV infection, including the ~80% (15 of 19) prediction rate of known HCV hepatocyte entry factors. Because molecular mimicry is a general concept, our bioinformatics strategy is a timely approach to identify new targets for antiviral research, not only for HCV but also for other viruses.
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Affiliation(s)
| | - Walt Y. L. Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ting Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ming-Jing Hwang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- * E-mail:
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17
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Hepatitis C Virus-Induced Rab32 Aggregation and Its Implications for Virion Assembly. J Virol 2017; 91:JVI.01662-16. [PMID: 27852857 DOI: 10.1128/jvi.01662-16] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 11/09/2016] [Indexed: 01/09/2023] Open
Abstract
Hepatitis C virus (HCV) is highly dependent on cellular factors for viral propagation. Using high-throughput next-generation sequencing, we analyzed the host transcriptomic changes and identified 30 candidate genes which were upregulated in cell culture-grown HCV (HCVcc)-infected cells. Of these candidates, we selected Rab32 for further investigation. Rab32 is a small GTPase that regulates a variety of intracellular membrane-trafficking events in various cell types. In this study, we demonstrated that both mRNA and protein levels of Rab32 were increased in HCV-infected cells. Furthermore, we showed that HCV infection converted the predominantly expressed GTP-bound Rab32 to GDP-bound Rab32, contributing to the aggregation of Rab32 and thus making it less sensitive to cellular degradation machinery. In addition, GDP-bound Rab32 selectively interacted with HCV core protein and deposited core protein into the endoplasmic reticulum (ER)-associated Rab32-derived aggregated structures in the perinuclear region, which were likely to be viral assembly sites. Using RNA interference technology, we demonstrated that Rab32 was required for the assembly step but not for other stages of the HCV life cycle. Taken together, these data suggest that HCV may modulate Rab32 activity to facilitate virion assembly. IMPORTANCE Rab32, a member of the Ras superfamily of small GTPases, regulates various intracellular membrane-trafficking events in many cell types. In this study, we showed that HCV infection concomitantly increased Rab32 expression at the transcriptional level and altered the balance between GDP- and GTP-bound Rab32 toward production of Rab32-GDP. GDP-bound Rab32 selectively interacted with HCV core protein and enriched core in the ER-associated Rab32-derived aggregated structures that were probably necessary for viral assembly. Indeed, we showed that Rab32 was specifically required for the assembly of HCV. Collectively, our study identifies that Rab32 is a novel host factor essential for HCV particle assembly.
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18
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Gabor KA, Fessler MB. Roles of the Mevalonate Pathway and Cholesterol Trafficking in Pulmonary Host Defense. Curr Mol Pharmacol 2017; 10:27-45. [PMID: 26758950 PMCID: PMC6026538 DOI: 10.2174/1874467209666160112123603] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 08/01/2015] [Accepted: 12/23/2015] [Indexed: 01/17/2023]
Abstract
The mevalonic acid synthesis pathway, cholesterol, and lipoproteins play fundamental roles in lung physiology and the innate immune response. Recent literature investigating roles for cholesterol synthesis and trafficking in host defense against respiratory infection was critically reviewed. The innate immune response and the cholesterol biosynthesis/trafficking network regulate one another, with important implications for pathogen invasion and host defense in the lung. The activation of pathogen recognition receptors and downstream cellular host defense functions are critically sensitive to cellular cholesterol. Conversely, microorganisms can co-opt the sterol/lipoprotein network in order to facilitate replication and evade immunity. Emerging literature suggests the potential for harnessing these insights towards therapeutic development. Given that >50% of adults in the U.S. have serum cholesterol abnormalities and pneumonia remains a leading cause of death, the potential impact of cholesterol on pulmonary host defense is of tremendous public health significance and warrants further mechanistic and translational investigation.
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Affiliation(s)
| | - Michael B Fessler
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, P.O. Box 12233, Maildrop D2-01, Research Triangle Park, NC 27709, United States
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19
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Ji XY, Chen JH, Zheng GH, Huang MH, Zhang L, Yi H, Jin J, Jiang JD, Peng ZG, Li ZR. Design and Synthesis of Cajanine Analogues against Hepatitis C Virus through Down-Regulating Host Chondroitin Sulfate N-Acetylgalactosaminyltransferase 1. J Med Chem 2016; 59:10268-10284. [DOI: 10.1021/acs.jmedchem.6b01301] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xing-Yue Ji
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Jin-Hua Chen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Guang-Hui Zheng
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Meng-Hao Huang
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Lei Zhang
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Hong Yi
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Jie Jin
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Jian-Dong Jiang
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Zong-Gen Peng
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
| | - Zhuo-Rong Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, No.
1, Tiantan Xili, Beijing 100050, China
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20
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Hepatitis C virus: life cycle in cells, infection and host response, and analysis of molecular markers influencing the outcome of infection and response to therapy. Clin Microbiol Infect 2016; 22:826-832. [PMID: 27592089 DOI: 10.1016/j.cmi.2016.08.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 08/16/2016] [Accepted: 08/25/2016] [Indexed: 12/13/2022]
Abstract
Hepatitis C virus (HCV) is a major global health burden accounting for around 170 million chronic infections worldwide. Since its discovery, which dates back to about 30 years ago, many details of the viral genome organization and the astonishing genetic diversity have been unveiled but, owing to the difficulty of culturing HCV in vitro and obtaining fully susceptible yet immunocompetent in vivo models, we are still a long way from the full comprehension of viral life cycle, host cell pathways facilitating or counteracting infection, pathogenetic mechanisms in vivo, and host defences. Here, we illustrate the viral life cycle into cells, describe the interplay between immune and genetic host factors shaping the course of infection, and provide details of the molecular approaches currently used to genotype, monitor replication in vivo, and study the emergence of drug-resistant viral variants.
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21
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Cuypers L, Snoeck J, Kerremans L, Libin P, Crabbé R, Van Dooren S, Vuagniaux G, Vandamme AM. HCV1b genome evolution under selective pressure of the cyclophilin inhibitor alisporivir during the DEB-025-HCV-203 phase II clinical trial. INFECTION GENETICS AND EVOLUTION 2016; 44:169-181. [PMID: 27374748 DOI: 10.1016/j.meegid.2016.06.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 12/18/2022]
Abstract
Major advances have revolutionized the HCV antiviral treatment field, with interferon-free combinations of direct-acting antivirals (DAAs) resulting into success rates of >90% for all HCV genotypes. Nevertheless, viral eradication at a global level stills remains challenging, stimulating the continued search for new affordable pan-genotypic drugs. To overcome selection of drug resistant variants, targeting host proteins can be an attractive mechanism of action. Alisporivir (Debio 025) is a potent pan-genotypic host-targeting antiviral agent, acting on cyclophilin A, which is necessary for HCV replication. The efficacy and safety of three different oral doses of alisporivir in combination with pegylated interferon-α2a given over a period of four weeks, was investigated in a randomized, double-blind and placebo-controlled phase IIa clinical trial, in 90 treatment-naïve subjects infected with chronic hepatitis C, wherefrom 58 HCV1b samples were selected for genetic sequencing purposes. Sequencing results were used to study the HCV genome for amino acid changes potentially related with selective pressure and resistance to alisporivir. By comparing baseline and on-treatment sequences, a large variation in proportion of amino acid changes was detected in all treatment arms. The NS5A variant D320E, which was previously identified during in vitro resistance selection and resulted in 3.6-fold reduced alisporivir susceptibility, emerged in two subjects in the alisporivir monotherapy arm. However, emergence of D320E appeared to be associated only with concurrent viral load rebound in one subject with 0.8log10IU/ml increase in HCV RNA. In general, for all datasets, low numbers of positions under positive selective pressure were observed, with no significant differences between naïve and treated sequences. Additionally, incomplete sequence information for some of the 22 patients and the low number of individuals per treatment arm, is limiting the power to assess the association of alisporivir or interferon treatment with the observed amino acid changes.
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Affiliation(s)
- Lize Cuypers
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium.
| | - Joke Snoeck
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium.
| | - Lien Kerremans
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium.
| | - Pieter Libin
- Artificial Intelligence Lab, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium.
| | - Raf Crabbé
- Debiopharm International S.A., Che. Messidor 5-7, P.O. Box 5911, 1002 Lausanne, Switzerland.
| | - Sonia Van Dooren
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium.
| | - Grégoire Vuagniaux
- Debiopharm International S.A., Che. Messidor 5-7, P.O. Box 5911, 1002 Lausanne, Switzerland.
| | - Anne-Mieke Vandamme
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Clinical and Epidemiological Virology, Minderbroedersstraat 10, 3000 Leuven, Belgium; Center for Global Health and Tropical Medicine, Unidade de Microbiologia, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Jungquiera 100, 1349-008 Lisbon, Portugal.
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22
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Mandal A, Ganta KK, Chaubey B. Combinations of siRNAs against La Autoantigen with NS5B or hVAP-A Have Additive Effect on Inhibition of HCV Replication. HEPATITIS RESEARCH AND TREATMENT 2016; 2016:9671031. [PMID: 27446609 PMCID: PMC4942654 DOI: 10.1155/2016/9671031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/23/2016] [Accepted: 05/30/2016] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus is major cause of chronic liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Presently available direct-acting antiviral drugs have improved success rate; however, high cost limits their utilization, especially in developing countries like India. In the present study, we evaluated anti-HCV potential of several siRNAs targeted against the HCV RNA-dependent RNA polymerase NS5B and cellular factors, La autoantigen, PSMA7, and human VAMP-associated protein to intercept different steps of viral life cycle. The target genes were downregulated individually as well as in combinations and their impact on viral replication was evaluated. Individual downregulation of La autoantigen, PSMA7, hVAP-A, and NS5B resulted in inhibition of HCV replication by about 67.2%, 50.7%, 39%, and 52%, respectively. However, antiviral effect was more pronounced when multiple genes were downregulated simultaneously. Combinations of siRNAs against La autoantigen with NS5B or hVAP-A resulted in greater inhibition in HCV replication. Our findings indicate that siRNA is a potential therapeutic tool for inhibiting HCV replication and simultaneously targeting multiple viral steps with the combination of siRNAs is more effective than silencing a single target.
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Affiliation(s)
- Anirban Mandal
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Krishna Kumar Ganta
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Binay Chaubey
- Centre for Advance Studies, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
- Laboratory of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, UG and MUG, Abrahama 58 Street, 80-307 Gdańsk, Poland
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Abstract
The treatment of HCV infection has evolved at an extremely rapid pace over the past few years. The development of direct-acting antiviral agents, which potently inhibit different stages in the viral life cycle, has led to the replacement of interferon with well-tolerated oral therapies with cure rates of >90% in most patient populations. Understanding the mechanisms of action of the various agents as well as related issues, including the molecular basis for resistance, helps to guide drug development and clinical use. In this Review, we provide a mechanistic description of NS3/4A protease inhibitors, nucleotide and non-nucleotide inhibitors of the NS5B viral polymerase and inhibitors of the NS5A protein, followed by a summary of clinical data from studies of each drug class alone and in combination. Remaining challenges in drug development efforts are also discussed.
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24
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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: 39] [Impact Index Per Article: 4.9] [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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25
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Ai T, Qiu L, Xie J, Geraghty RJ, Chen L. Design and synthesis of an activity-based protein profiling probe derived from cinnamic hydroxamic acid. Bioorg Med Chem 2015; 24:686-92. [PMID: 26753813 DOI: 10.1016/j.bmc.2015.12.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 12/14/2015] [Accepted: 12/22/2015] [Indexed: 12/19/2022]
Abstract
In our continued effort to discover new anti-hepatitis C virus (HCV) agents, we validated the anti-replicon activity of compound 1, a potent and selective anti-HCV hydroxamic acid recently reported by us. Generally favorable physicochemical and in vitro absorption, distribution, metabolism, and excretion (ADME) properties exhibited by 1 made it an ideal parent compound from which activity-based protein profiling (ABPP) probe 3 was designed and synthesized. Evaluation of probe 3 revealed that it possessed necessary anti-HCV activity and selectivity. Therefore, we have successfully obtained compound 3 as a suitable ABPP probe to identify potential molecular targets of compound 1. Probe 3 and its improved analogs are expected to join a growing list of ABPP probes that have made important contributions to not only the studies of biochemical and cellular functions but also discovery of selective inhibitors of protein targets.
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Affiliation(s)
- Teng Ai
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA
| | - Li Qiu
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA
| | - Jiashu Xie
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA
| | - Robert J Geraghty
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA
| | - Liqiang Chen
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA.
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26
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Host-Targeting Agents to Prevent and Cure Hepatitis C Virus Infection. Viruses 2015; 7:5659-85. [PMID: 26540069 PMCID: PMC4664971 DOI: 10.3390/v7112898] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 09/25/2015] [Accepted: 10/19/2015] [Indexed: 12/13/2022] Open
Abstract
Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma (HCC) which are leading indications of liver transplantation (LT). To date, there is no vaccine to prevent HCV infection and LT is invariably followed by infection of the liver graft. Within the past years, direct-acting antivirals (DAAs) have had a major impact on the management of chronic hepatitis C, which has become a curable disease in the majority of DAA-treated patients. In contrast to DAAs that target viral proteins, host-targeting agents (HTAs) interfere with cellular factors involved in the viral life cycle. By acting through a complementary mechanism of action and by exhibiting a generally higher barrier to resistance, HTAs offer a prospective option to prevent and treat viral resistance. Indeed, given their complementary mechanism of action, HTAs and DAAs can act in a synergistic manner to reduce viral loads. This review summarizes the different classes of HTAs against HCV infection that are in preclinical or clinical development and highlights their potential to prevent HCV infection, e.g., following LT, and to tailor combination treatments to cure chronic HCV infection.
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Monoclonal antibodies: Principles and applications of immmunodiagnosis and immunotherapy for hepatitis C virus. World J Hepatol 2015. [PMID: 26464752 DOI: 10.4254/wjh.v7.i22.2369.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Hepatitis C virus (HCV) is a major health problem worldwide. Early detection of the infection will help better management of the infected cases. The monoclonal antibodies (mAb) of mice are predominantly used for the immunodiagnosis of several viral, bacterial, and parasitic antigens. Serological detection of HCV antigens and antibodies provide simple and rapid methods of detection but lack sensitivity specially in the window phase between the infection and antibody development. Human mAb are used in the immunotherapy of several blood malignancies, such as lymphoma and leukemia, as well as for autoimmune diseases. In this review article, we will discuss methods of mouse and human monoclonal antibody production. We will demonstrate the role of mouse mAb in the detection of HCV antigens as rapid and sensitive immunodiagnostic assays for the detection of HCV, which is a major health problem throughout the world, particularly in Egypt. We will discuss the value of HCV-neutralizing antibodies and their roles in the immunotherapy of HCV infections and in HCV vaccine development. We will also discuss the different mechanisms by which the virus escape the effect of neutralizing mAb. Finally, we will discuss available and new trends to produce antibodies, such as egg yolk-based antibodies (IgY), production in transgenic plants, and the synthetic antibody mimics approach.
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28
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Tabll A, Abbas AT, El-Kafrawy S, Wahid A. Monoclonal antibodies: Principles and applications of immmunodiagnosis and immunotherapy for hepatitis C virus. World J Hepatol 2015; 7:2369-2383. [PMID: 26464752 PMCID: PMC4598607 DOI: 10.4254/wjh.v7.i22.2369] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 08/05/2015] [Accepted: 09/08/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a major health problem worldwide. Early detection of the infection will help better management of the infected cases. The monoclonal antibodies (mAb) of mice are predominantly used for the immunodiagnosis of several viral, bacterial, and parasitic antigens. Serological detection of HCV antigens and antibodies provide simple and rapid methods of detection but lack sensitivity specially in the window phase between the infection and antibody development. Human mAb are used in the immunotherapy of several blood malignancies, such as lymphoma and leukemia, as well as for autoimmune diseases. In this review article, we will discuss methods of mouse and human monoclonal antibody production. We will demonstrate the role of mouse mAb in the detection of HCV antigens as rapid and sensitive immunodiagnostic assays for the detection of HCV, which is a major health problem throughout the world, particularly in Egypt. We will discuss the value of HCV-neutralizing antibodies and their roles in the immunotherapy of HCV infections and in HCV vaccine development. We will also discuss the different mechanisms by which the virus escape the effect of neutralizing mAb. Finally, we will discuss available and new trends to produce antibodies, such as egg yolk-based antibodies (IgY), production in transgenic plants, and the synthetic antibody mimics approach.
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29
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Gallay PA, Bobardt MD, Chatterji U, Trepanier DJ, Ure D, Ordonez C, Foster R. The Novel Cyclophilin Inhibitor CPI-431-32 Concurrently Blocks HCV and HIV-1 Infections via a Similar Mechanism of Action. PLoS One 2015; 10:e0134707. [PMID: 26263487 PMCID: PMC4532424 DOI: 10.1371/journal.pone.0134707] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 07/13/2015] [Indexed: 12/17/2022] Open
Abstract
HCV-related liver disease is the main cause of morbidity and mortality of HCV/HIV-1 co-infected patients. Despite the recent advent of anti-HCV direct acting antivirals (DAAs), the treatment of HCV/HIV-1 co-infected patients remains a challenge, as these patients are refractory to most therapies and develop liver fibrosis, cirrhosis and liver cancer more often than HCV mono-infected patients. Until the present study, there was no suitable in vitro assay to test the inhibitory activity of drugs on HCV/HIV-1 co-infection. Here we developed a novel in vitro "co-infection" model where HCV and HIV-1 concurrently replicate in their respective main host target cells--human hepatocytes and CD4+ T-lymphocytes. Using this co-culture model, we demonstrate that cyclophilin inhibitors (CypI), including a novel cyclosporin A (CsA) analog, CPI-431-32, simultaneously inhibits replication of both HCV and HIV-1 when added pre- and post-infection. In contrast, the HIV-1 protease inhibitor nelfinavir or the HCV NS5A inhibitor daclatasvir only blocks the replication of a single virus in the "co-infection" system. CPI-431-32 efficiently inhibits HCV and HIV-1 variants, which are normally resistant to DAAs. CPI-431-32 is slightly, but consistently more efficacious than the most advanced clinically tested CypI--alisporivir (ALV)--at interrupting an established HCV/HIV-1 co-infection. The superior antiviral efficacy of CPI-431-32 over ALV correlates with its higher potency inhibition of cyclophilin A (CypA) isomerase activity and at preventing HCV NS5A-CypA and HIV-1 capsid-CypA interactions known to be vital for replication of the respective viruses. Moreover, we obtained evidence that CPI-431-32 prevents the cloaking of both the HIV-1 and HCV genomes from cellular sensors. Based on these results, CPI-431-32 has the potential, as a single agent or in combination with DAAs, to inhibit both HCV and HIV-1 infections.
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Affiliation(s)
- Philippe A. Gallay
- Department of Immunology & Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Michael D. Bobardt
- Department of Immunology & Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Udayan Chatterji
- Department of Immunology & Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Daniel J. Trepanier
- Ciclofilin Pharmaceuticals Inc., San Diego, California, United States of America
| | - Daren Ure
- Ciclofilin Pharmaceuticals Inc., San Diego, California, United States of America
| | - Cosme Ordonez
- Ciclofilin Pharmaceuticals Inc., San Diego, California, United States of America
| | - Robert Foster
- Ciclofilin Pharmaceuticals Inc., San Diego, California, United States of America
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Yamauchi S, Takeuchi K, Chihara K, Sun X, Honjoh C, Yoshiki H, Hotta H, Sada K. Hepatitis C Virus Particle Assembly Involves Phosphorylation of NS5A by the c-Abl Tyrosine Kinase. J Biol Chem 2015. [PMID: 26203192 DOI: 10.1074/jbc.m115.666859] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) nonstructural protein 5A (NS5A) is thought to regulate the replication of viral RNA and the assembly of virus particles in a serine/threonine phosphorylation-dependent manner. However, the host kinases that phosphorylate NS5A have not been fully identified. Here, we show that HCV particle assembly involves the phosphorylation of NS5A by the c-Abl tyrosine kinase. Pharmacological inhibition or knockdown of c-Abl reduces the production of infectious HCV (J6/JFH1) particles in Huh-7.5 cells without markedly affecting viral RNA translation and replication. NS5A is tyrosine-phosphorylated in HCV-infected cells, and this phosphorylation is also reduced by the knockdown of c-Abl. Mutational analysis reveals that NS5A tyrosine phosphorylation is dependent, at least in part, on Tyr(330) (Tyr(2306) in polyprotein numbering). Mutation of this residue to phenylalanine reduces the production of infectious HCV particles but does not affect the replication of the JFH1 subgenomic replicon. These findings suggest that c-Abl promotes HCV particle assembly by phosphorylating NS5A at Tyr(330).
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Affiliation(s)
- Shota Yamauchi
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences, the Organization for Life Science Advancement Programs, University of Fukui, Fukui 910-1193, Japan and
| | - Kenji Takeuchi
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences, the Organization for Life Science Advancement Programs, University of Fukui, Fukui 910-1193, Japan and
| | - Kazuyasu Chihara
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences, the Organization for Life Science Advancement Programs, University of Fukui, Fukui 910-1193, Japan and
| | - Xuedong Sun
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences
| | - Chisato Honjoh
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences, the Third Department of Internal Medicine, Faculty of Medical Sciences, and
| | - Hatsumi Yoshiki
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences
| | - Hak Hotta
- the Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Kiyonao Sada
- From the Division of Genome Science and Microbiology, Department of Pathological Sciences, Faculty of Medical Sciences, the Organization for Life Science Advancement Programs, University of Fukui, Fukui 910-1193, Japan and
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31
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Niu Y, Si Y, Li Y, Chi X, Li X, Liu X, Li D, Cheng M, Fan J, Si S, Yang W. A novel small-molecule inhibitor of hepatitis C virus replication acts by suppressing signal transducer and activator of transcription 3. J Antimicrob Chemother 2015; 70:2013-23. [PMID: 25858355 DOI: 10.1093/jac/dkv077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 03/05/2015] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVES Hepatitis C virus (HCV) infects hepatocytes and causes liver damage. The aim of this study was to identify new classes of host-targeting anti-HCV compounds that may provide novel approaches for antiviral treatment regimens. METHODS Cell culture-derived HCV (HCVcc), replicons and pseudoparticles were used in combination with high-throughput screening, reporter gene assays and cytotoxicity and signalling pathway analyses. RESULTS A small-molecule inhibitor of HCV, N-(cyclopropyl(phenyl)methyl)thieno[2,3-d]pyrimidin-4-amine, designated IB-32, was identified by screening a compound library with a Jc1-luc HCVcc assay. By using various virus models, HCV replication was identified as the predominant step of IB-32's action. IB-32 inhibited HCVcc (genotype 2a) and HCV replicons (genotype 1b) at low nanomolar ranges (with IC50s of 40 ± 8 and 100 ± 15 nM, respectively). IB-32 was found to be non-toxic when tested against a panel of human cell lines in vitro at the effective antiviral dose. Mechanistically, IB-32 strongly inhibited STAT3 (Tyr705) phosphorylation, a necessary cellular factor for HCV replication and a pivotal therapeutic target for multiple cancers. Furthermore, the inhibition of HCV replication by IB-32 was augmented in cells with STAT3 knockdown. In contrast, the inhibitory effect of IB-32 was attenuated in cells overexpressing a constitutively active form of STAT3. CONCLUSION The results presented here identify a promising STAT3-targeting anti-HCV therapeutic candidate. This novel small molecule could be further optimized and developed for use as both an antiviral and an anti-cancer drug.
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Affiliation(s)
- Yuqiang Niu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Youhui Si
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yan Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiaojing Chi
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiang Li
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiuying Liu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Duan Li
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Min Cheng
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jingjing Fan
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Shuyi Si
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Wei Yang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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32
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The inhibitory effects of anacardic acid on hepatitis C virus life cycle. PLoS One 2015; 10:e0117514. [PMID: 25658101 PMCID: PMC4319966 DOI: 10.1371/journal.pone.0117514] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/26/2014] [Indexed: 01/01/2023] Open
Abstract
Hepatitis C virus (HCV) is a small positive-sense single-stranded RNA virus that causes severe liver diseases. Current anti-HCV therapies involving direct-acting antivirals have significantly enhanced efficacy in comparison to traditional interferon and ribavirin combination. However, further improvement is needed to eradicate HCV. Anacardic acid (AnA) is a phytochemical compound that can inhibit the activity of various cellular enzymes including histone acetyltransferases (HATs). In this study, we investigated the effects of AnA on different phases of HCV life cycle. Our data showed that AnA can inhibit HCV entry, replication, translation, and virion secretion in a dose-dependent manner with no measurable effects on cell viability. In addition, we showed that two HAT inhibitors and knocking down HAT (PCAF) by RNAi can reduce HCV replication, suggesting a mechanism of AnA’s inhibitory effects on HCV. Elucidation of the AnA-mediated inhibitory mechanism should facilitate the development of new drug candidates for HCV infection.
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33
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Barve A, Kovacs SJ, Ke J, Crabbe R, Grosgurin P, Menetrey A, Nicolas-Métral V, Dabovic K, Dole K, Zhang J, Praestgaard J, Sunkara G, Stein D. The effects of CYP3A4 induction and inhibition on the pharmacokinetics of alisporivir in humans. Clin Pharmacol Drug Dev 2015; 4:25-32. [PMID: 27128001 DOI: 10.1002/cpdd.114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 03/05/2014] [Indexed: 11/06/2022]
Abstract
In vitro data suggest that alisporivir is a substrate and inhibitor of CYP3A4 and P-gp. Hence, the potential for drug-drug interactions when alisporivir is co-administered with CYP3A4 and/or P-gp inhibitors such as ketoconazole, azithromycin and CYP3A4 inducers such as rifampin were evaluated in three separate clinical studies. Co-administration with ketoconazole (a strong CYP3A4 inhibitor) increased the Cmax , AUC and terminal elimination half-life of alisporivir by approximately two-, eight- ,and threefold, respectively. Co-administration with azithromycin (a putative weak CYP3A4 inhibitor and substrate) had no impact on the Cmax and AUC of alisporivir. Rifampin (a CYP3A4 inducer) caused an approximate 90% reduction in alisporivir Cmax and AUC and a fourfold reduction in alisporivir terminal elimination half-life. Alisporivir as an inhibitor of CYP3A4 caused a 39% increase in azithromycin exposure. The results from these studies establish alisporivir as a sensitive CYP3A4 substrate in vivo. Consequently, co-administered potent CYP3A4 inhibitors and inducers are likely to cause clinically significant changes in the exposure to alisporivir.
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Affiliation(s)
- Avantika Barve
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | - Steven J Kovacs
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | - June Ke
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | | | | | | | | | - Kristina Dabovic
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | - Kiran Dole
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Jie Zhang
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | - Jens Praestgaard
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
| | | | - Daniel Stein
- Novartis Institutes for Biomedical Research, East Hanover, NJ, USA
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34
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Twenty-five years of type I interferon-based treatment: a critical analysis of its therapeutic use. Cytokine Growth Factor Rev 2014; 26:121-31. [PMID: 25578520 PMCID: PMC7108252 DOI: 10.1016/j.cytogfr.2014.12.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 02/06/2023]
Abstract
The clinical exploitation of type I interferon (IFN) as an antiviral and antineoplastic agent is based on the properties originally attributed to this cytokine family, with schedules reflecting only their antiviral and antiproliferative activities. Nevertheless, type I IFN has emerged as a central activator of the innate immunity. As current schedules of treatment for chronic hepatitis C and for hematological and solid tumors, based on the continuous administration of recombinant type I IFN or pegylated formulations, disregard viral resistance, host genetic variants predicting treatment outcome and mechanisms of refractoriness, new administration schedules, the combination of type I IFN with new drugs and the increased monitoring of patients’ susceptibility to type I IFN are expected to provide a new life to this valuable cytokine.
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35
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Ai T, Xu Y, Qiu L, Geraghty RJ, Chen L. Hydroxamic Acids Block Replication of Hepatitis C Virus. J Med Chem 2014; 58:785-800. [DOI: 10.1021/jm501330g] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Teng Ai
- Center for Drug Design, Academic
Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, Minnesota 55455, United States
| | - Yanli Xu
- Center for Drug Design, Academic
Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, Minnesota 55455, United States
| | - Li Qiu
- Center for Drug Design, Academic
Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, Minnesota 55455, United States
| | - Robert J. Geraghty
- Center for Drug Design, Academic
Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, Minnesota 55455, United States
| | - Liqiang Chen
- Center for Drug Design, Academic
Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, Minnesota 55455, United States
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36
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Welzel TM, Dultz G, Zeuzem S. Interferon-free antiviral combination therapies without nucleosidic polymerase inhibitors. J Hepatol 2014; 61:S98-S107. [PMID: 25443350 DOI: 10.1016/j.jhep.2014.08.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/07/2014] [Accepted: 08/09/2014] [Indexed: 01/10/2023]
Abstract
The establishment of robust HCV cell culture systems and characterization of the viral life cycle provided the molecular basis for highly innovative, successful years in HCV drug development. With the identification of direct-acting antiviral agents (DAAs), such as NS3/4A protease inhibitors, NS5A replication complex inhibitors, nucleotide and non-nucleoside polymerase inhibitors, as well as host cell targeting agents, novel therapeutic strategies were established and competitively entered clinical testing. The first-in-class NS3/4A protease inhibitors telaprevir and boceprevir, approved in 2011, were recently outpaced by the pan-genotypic nucleotide polymerase inhibitor sofosbuvir that in combination with pegylated interferon and ribavirin, further shortens therapy durations and also offers the first interferon-free HCV treatment option. In the challenging race towards the goal of interferon-free HCV therapies, however, several oral DAA regimens without nucleotide polymerase inhibitors that combine a NS3/4A protease inhibitor, a NS5A inhibitor and/or a non-nucleoside polymerase inhibitor yielded competitive results. Second generation NS3/4A protease and NS5A inhibitors promise an improved genotypic coverage and a high resistance barrier. Results of novel DAA combination therapies without the backbone of a nucleotide polymerase inhibitor, as well as treatment strategies involving host targeting agents are reviewed herein.
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Affiliation(s)
- Tania Mara Welzel
- Department of Medicine 1, Johann Wolfgang Goethe-University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Georg Dultz
- Department of Medicine 1, Johann Wolfgang Goethe-University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Stefan Zeuzem
- Department of Medicine 1, Johann Wolfgang Goethe-University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
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37
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Tomasello E, Pollet E, Vu Manh TP, Uzé G, Dalod M. Harnessing Mechanistic Knowledge on Beneficial Versus Deleterious IFN-I Effects to Design Innovative Immunotherapies Targeting Cytokine Activity to Specific Cell Types. Front Immunol 2014; 5:526. [PMID: 25400632 PMCID: PMC4214202 DOI: 10.3389/fimmu.2014.00526] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 10/07/2014] [Indexed: 12/15/2022] Open
Abstract
Type I interferons (IFN-I) were identified over 50 years ago as cytokines critical for host defense against viral infections. IFN-I promote anti-viral defense through two main mechanisms. First, IFN-I directly reinforce or induce de novo in potentially all cells the expression of effector molecules of intrinsic anti-viral immunity. Second, IFN-I orchestrate innate and adaptive anti-viral immunity. However, IFN-I responses can be deleterious for the host in a number of circumstances, including secondary bacterial or fungal infections, several autoimmune diseases, and, paradoxically, certain chronic viral infections. We will review the proposed nature of protective versus deleterious IFN-I responses in selected diseases. Emphasis will be put on the potentially deleterious functions of IFN-I in human immunodeficiency virus type 1 (HIV-1) infection, and on the respective roles of IFN-I and IFN-III in promoting resolution of hepatitis C virus (HCV) infection. We will then discuss how the balance between beneficial versus deleterious IFN-I responses is modulated by several key parameters including (i) the subtypes and dose of IFN-I produced, (ii) the cell types affected by IFN-I, and (iii) the source and timing of IFN-I production. Finally, we will speculate how integration of this knowledge combined with advanced biochemical manipulation of the activity of the cytokines should allow designing innovative immunotherapeutic treatments in patients. Specifically, we will discuss how induction or blockade of specific IFN-I responses in targeted cell types could promote the beneficial functions of IFN-I and/or dampen their deleterious effects, in a manner adapted to each disease.
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Affiliation(s)
- Elena Tomasello
- UM2, Centre d'Immunologie de Marseille-Luminy (CIML), Aix-Marseille University , Marseille , France ; U1104, Institut National de la Santé et de la Recherche Médicale (INSERM) , Marseille , France ; UMR7280, Centre National de la Recherche Scientifique (CNRS) , Marseille , France
| | - Emeline Pollet
- UM2, Centre d'Immunologie de Marseille-Luminy (CIML), Aix-Marseille University , Marseille , France ; U1104, Institut National de la Santé et de la Recherche Médicale (INSERM) , Marseille , France ; UMR7280, Centre National de la Recherche Scientifique (CNRS) , Marseille , France
| | - Thien-Phong Vu Manh
- UM2, Centre d'Immunologie de Marseille-Luminy (CIML), Aix-Marseille University , Marseille , France ; U1104, Institut National de la Santé et de la Recherche Médicale (INSERM) , Marseille , France ; UMR7280, Centre National de la Recherche Scientifique (CNRS) , Marseille , France
| | - Gilles Uzé
- UMR 5235, Centre National de la Recherche Scientifique (CNRS), University Montpellier II , Montpellier , France
| | - Marc Dalod
- UM2, Centre d'Immunologie de Marseille-Luminy (CIML), Aix-Marseille University , Marseille , France ; U1104, Institut National de la Santé et de la Recherche Médicale (INSERM) , Marseille , France ; UMR7280, Centre National de la Recherche Scientifique (CNRS) , Marseille , France
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38
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Fabrizi F, Messa P, Martin P. Recent advances on hepatitis C virus in dialysis population. Kidney Blood Press Res 2014; 39:260-71. [PMID: 25171295 DOI: 10.1159/000355803] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2014] [Indexed: 01/08/2023] Open
Abstract
Hepatitis C virus (HCV) infection remains common among patients undergoing regular dialysis and good evidence supports the detrimental role of HCV on survival in patients undergoing maintenance dialysis. According to an updated meta-analysis of clinical studies (n=15; 195,370 unique patients on maintenance dialysis), the summary estimate for adjusted relative risk (all-cause mortality) with anti-HCV across the published studies was 1.32 with a 95% Confidence Intervals of 1.24; 1.42, homogeneity assumption was not rejected. Various mechanisms support the excess death risk of HCV-infected patients on regular dialysis, in addition to liver disease-related mortality. The adjusted relative risk for cardiovascular mortality among HCV-infected patients on regular dialysis was 1.26 (95% Confidence Intervals, 1.10; 1.45); the increased cardiovascular mortality in anti-HCV positive patients has been associated in part to malnutrition and chronic inflammation. The current standard of care for HCV in dialysis population is combined antiviral therapy (pegylated interferon plus ribavirin) with a rate of viral response of around 60%. Triple therapy with telaprevir proved to be effective and safe in dialysis patients with HCV but only anecdotal evidence exists. Antiviral treatment of HCV-infected patients on maintenance dialysis could lead to cure the liver damage and the extrahepatic complications. The future availability of all-oral interferon/ribavirin free regimens for antiviral treatment of HCV will help nephrologists to improve survival in this high-risk group.
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Affiliation(s)
- Fabrizio Fabrizi
- Division of Nephrology, Maggiore Hospital, IRCCS Foundation, Milano, Italy
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39
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Seed sequence-matched controls reveal limitations of small interfering RNA knockdown in functional and structural studies of hepatitis C virus NS5A-MOBKL1B interaction. J Virol 2014; 88:11022-33. [PMID: 25031347 DOI: 10.1128/jvi.01582-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
UNLABELLED Hepatitis C virus (HCV) is a widespread human pathogen causing liver cirrhosis and cancer. Similar to the case for other viruses, HCV depends on host and viral factors to complete its life cycle. We used proteomic and yeast two-hybrid approaches to elucidate host factors involved in HCV nonstructural protein NS5A function and found that MOBKL1B interacts with NS5A. Initial experiments with small interfering RNA (siRNA) knockdown suggesting a role in HCV replication led us to examine the interaction using biochemical and structural approaches. As revealed by a cocrystal structure of a core MOBKL1B-NS5A peptide complex at 1.95 Å, NS5A binds to a hydrophobic patch on the MOBKL1B surface. Biosensor binding assays identified a highly conserved, 18-amino-acid binding site in domain II of NS5A, which encompasses residues implicated in cyclophilin A (CypA)-dependent HCV RNA replication. However, a CypA-independent HCV variant had reduced replication in MOBKL1B knockdown cells, even though its NS5A does not interact with MOBKL1B. These discordant results prompted more extensive studies of MOBKL1B gene knockdowns, which included additional siRNAs and specifically matched seed sequence siRNA controls. We found that reduced virus replication after treating cells with MOBKL1B siRNA was actually due to off-target inhibition, which indicated that the initial finding of virus replication dependence on the MOBKL1B-NS5A interaction was incorrect. Ultimately, using several approaches, we found no relationship of the MOBKL1B-NS5A interaction to virus replication. These findings collectively serve as a reminder to investigators and scientific reviewers of the pervasive impact of siRNA off-target effects on interpretation of biological data. IMPORTANCE Our study illustrates an underappreciated shortcoming of siRNA gene knockdown technology. We initially identified a cellular protein, MOBKL1B, as a binding partner with the NS5A protein of hepatitis C virus (HCV). MOBKL1B siRNA, but not irrelevant RNA, treatment was associated with both reduced virus replication and the absence of MOBKL1B. Believing that HCV replication depended on the MOBKL1B-NS5A interaction, we carried out structural and biochemical analyses. Unexpectedly, an HCV variant lacking the MOBKL1B-NS5A interaction could not replicate after cells were treated with MOBKL1B siRNA. By repeating the MOBKL1B siRNA knockdowns and including seed sequence-matched siRNA instead of irrelevant siRNA as a control, we found that the MOBKL1B siRNAs utilized had off-target inhibitory effects on virus replication. Collectively, our results suggest that stricter controls must be utilized in all RNA interference (RNAi)-mediated gene knockdown experiments to ensure sound conclusions and a reliable scientific knowledge database.
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Jiang X, Kanda T, Wu S, Nakamoto S, Saito K, Shirasawa H, Kiyohara T, Ishii K, Wakita T, Okamoto H, Yokosuka O. Suppression of La antigen exerts potential antiviral effects against hepatitis A virus. PLoS One 2014; 9:e101993. [PMID: 24999657 PMCID: PMC4084951 DOI: 10.1371/journal.pone.0101993] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 06/12/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Despite the development and availability of hepatitis A virus (HAV) vaccine, HAV infection is still a major cause of acute hepatitis that occasionally leads to fatal liver disease. HAV internal ribosomal entry-site (IRES) is one of the attractive targets of antiviral agents against HAV. The aim of the present study is to evaluate the impact of La, one of the cellular proteins, on HAV IRES-mediated translation and HAV replication. METHODS AND FINDINGS We investigated the therapeutic feasibility of siRNAs specific for cellular cofactors for HAV IRES-mediated translation in cell culture. It was revealed that siRNA against La could inhibit HAV IRES activities as well as HAV subgenomic replication. We also found that the Janus kinase (JAK) inhibitors SD-1029 and AG490, which reduce La expression, could inhibit HAV IRES activities as well as HAV replication. CONCLUSIONS Inhibition of La by siRNAs and chemical agents could lead to the efficient inhibition of HAV IRES-mediated translation and HAV replication in cell culture models. La might play important roles in HAV replication and is being exploited as one of the therapeutic targets of host-targeting antivirals.
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Affiliation(s)
- Xia Jiang
- Department of Gastroenterology and Nephrology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Tatsuo Kanda
- Department of Gastroenterology and Nephrology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Shuang Wu
- Department of Gastroenterology and Nephrology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Shingo Nakamoto
- Department of Molecular Virology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Kengo Saito
- Department of Molecular Virology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Hiroshi Shirasawa
- Department of Molecular Virology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - Tomoko Kiyohara
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama, Japan
| | - Koji Ishii
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama, Japan
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Japan
| | - Osamu Yokosuka
- Department of Gastroenterology and Nephrology, Chiba University, Graduate School of Medicine, Chiba, Japan
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Chinnaswamy S. Genetic variants at the IFNL3 locus and their association with hepatitis C virus infections reveal novel insights into host-virus interactions. J Interferon Cytokine Res 2014; 34:479-97. [PMID: 24555572 PMCID: PMC4080901 DOI: 10.1089/jir.2013.0113] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 11/25/2013] [Indexed: 12/19/2022] Open
Abstract
Human genetic variation plays a critical role in both spontaneous clearance of and response to interferon (IFN)-based therapies against hepatitis C virus (HCV) as shown by the success of recent genome-wide association studies (GWAS). Several GWAS and later validation studies have shown that single nucleotide polymorphisms (SNPs) at the IFNL3 (formerly IL28B) locus on chromosome 19 are involved in eliminating HCV in human patients. No doubt that this information is helping clinicians worldwide in making better clinical decisions in anti-HCV therapy, but the biological mechanisms involving the SNPs leading to differential responses to therapy and spontaneous clearance of HCV remain elusive. Recent reports including the discovery of a novel IFN (IFN-λ4) gene at the IFNL3 locus and in vitro functional studies implicating 2 SNPs as causal variants lead to novel conclusions and perhaps to new directions in research. An attempt is made in this review to summarize the major findings of the GWAS, the efforts involved in the discovery of causal SNPs; and to explain the biological basis for spontaneous clearance and response to treatment in HCV infections.
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