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Vanhoye X, Janin A, Caillaud A, Rimbert A, Venet F, Gossez M, Dijk W, Marmontel O, Nony S, Chatelain C, Durand C, Lindenbaum P, Rieusset J, Cariou B, Moulin P, Di Filippo M. APOB CRISPR-Cas9 Engineering in Hypobetalipoproteinemia: A Promising Tool for Functional Studies of Novel Variants. Int J Mol Sci 2022; 23:4281. [PMID: 35457099 PMCID: PMC9030618 DOI: 10.3390/ijms23084281] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/04/2022] [Accepted: 04/11/2022] [Indexed: 02/01/2023] Open
Abstract
Hypobetalipoproteinemia is characterized by LDL-cholesterol and apolipoprotein B (apoB) plasma levels below the fifth percentile for age and sex. Familial hypobetalipoproteinemia (FHBL) is mostly caused by premature termination codons in the APOB gene, a condition associated with fatty liver and steatohepatitis. Nevertheless, many families with a FHBL phenotype carry APOB missense variants of uncertain significance (VUS). We here aimed to develop a proof-of-principle experiment to assess the pathogenicity of VUS using the genome editing of human liver cells. We identified a novel heterozygous APOB-VUS (p.Leu351Arg), in a FHBL family. We generated APOB knock-out (KO) and APOB-p.Leu351Arg knock-in Huh7 cells using CRISPR-Cas9 technology and studied the APOB expression, synthesis and secretion by digital droplet PCR and ELISA quantification. The APOB expression was decreased by 70% in the heterozygous APOB-KO cells and almost abolished in the homozygous-KO cells, with a consistent decrease in apoB production and secretion. The APOB-p.Leu351Arg homozygous cells presented with a 40% decreased APOB expression and undetectable apoB levels in cellular extracts and supernatant. Thus, the p.Leu351Arg affected the apoB secretion, which led us to classify this new variant as likely pathogenic and to set up a hepatic follow-up in this family. Therefore, the functional assessment of APOB-missense variants, using gene-editing technologies, will lead to improvements in the molecular diagnosis of FHBL and the personalized follow-up of these patients.
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Affiliation(s)
- Xavier Vanhoye
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
| | - Alexandre Janin
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Université Claude Bernard Lyon 1, Université de Lyon, F-69008 Lyon, France
| | - Amandine Caillaud
- Institut du Thorax, Nantes Université, CHU Nantes, CNRS, INSERM, F-44000 Nantes, France; (A.C.); (B.C.)
| | - Antoine Rimbert
- Institut du Thorax, Nantes Université, CNRS, INSERM, F-44000 Nantes, France; (A.R.); (W.D.); (P.L.)
| | - Fabienne Venet
- Laboratoire d’Immunologie, Edouard Herriot Hospital, Hospices Civils de Lyon, F-69437 Lyon, France; (F.V.); (M.G.)
- Centre International de Recherche en Infectiologie (CIRI), INSERM U1111, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université Claude Bernard-Lyon 1, F-69364 Lyon, France
| | - Morgane Gossez
- Laboratoire d’Immunologie, Edouard Herriot Hospital, Hospices Civils de Lyon, F-69437 Lyon, France; (F.V.); (M.G.)
- Centre International de Recherche en Infectiologie (CIRI), INSERM U1111, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université Claude Bernard-Lyon 1, F-69364 Lyon, France
| | - Wieneke Dijk
- Institut du Thorax, Nantes Université, CNRS, INSERM, F-44000 Nantes, France; (A.R.); (W.D.); (P.L.)
| | - Oriane Marmontel
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
- CarMen Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, F-69364 Lyon, France; (C.D.); (J.R.); (P.M.)
| | - Séverine Nony
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
| | - Charlotte Chatelain
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
| | - Christine Durand
- CarMen Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, F-69364 Lyon, France; (C.D.); (J.R.); (P.M.)
| | - Pierre Lindenbaum
- Institut du Thorax, Nantes Université, CNRS, INSERM, F-44000 Nantes, France; (A.R.); (W.D.); (P.L.)
| | - Jennifer Rieusset
- CarMen Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, F-69364 Lyon, France; (C.D.); (J.R.); (P.M.)
| | - Bertrand Cariou
- Institut du Thorax, Nantes Université, CHU Nantes, CNRS, INSERM, F-44000 Nantes, France; (A.C.); (B.C.)
| | - Philippe Moulin
- CarMen Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, F-69364 Lyon, France; (C.D.); (J.R.); (P.M.)
- Fédération d’Endocrinologie, Maladies Métaboliques, Diabète et Nutrition, Hôpital Louis Pradel, Hospices Civils de Lyon, F-69677 Bron, France
| | - Mathilde Di Filippo
- Service de Biochimie et de Biologie Moléculaire, Laboratoire de Biologie Médicale MultiSites, Hospices Civils de Lyon, F-69677 Bron, France; (X.V.); (A.J.); (O.M.); (S.N.); (C.C.)
- CarMen Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, F-69364 Lyon, France; (C.D.); (J.R.); (P.M.)
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Domain 2 of Hepatitis C Virus Protein NS5A Activates Glucokinase and Induces Lipogenesis in Hepatocytes. Int J Mol Sci 2022; 23:ijms23020919. [PMID: 35055105 PMCID: PMC8780509 DOI: 10.3390/ijms23020919] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/05/2022] [Accepted: 01/12/2022] [Indexed: 02/04/2023] Open
Abstract
Hepatitis C virus (HCV) relies on cellular lipid metabolism for its replication, and actively modulates lipogenesis and lipid trafficking in infected hepatocytes. This translates into an intracellular accumulation of triglycerides leading to liver steatosis, cirrhosis and hepatocellular carcinoma, which are hallmarks of HCV pathogenesis. While the interaction of HCV with hepatocyte metabolic pathways is patent, how viral proteins are able to redirect central carbon metabolism towards lipogenesis is unclear. Here, we report that the HCV protein NS5A activates the glucokinase (GCK) isoenzyme of hexokinases through its D2 domain (NS5A-D2). GCK is the first rate-limiting enzyme of glycolysis in normal hepatocytes whose expression is replaced by the hexokinase 2 (HK2) isoenzyme in hepatocellular carcinoma cell lines. We took advantage of a unique cellular model specifically engineered to re-express GCK instead of HK2 in the Huh7 cell line to evaluate the consequences of NS5A-D2 expression on central carbon and lipid metabolism. NS5A-D2 increased glucose consumption but decreased glycogen storage. This was accompanied by an altered mitochondrial respiration, an accumulation of intracellular triglycerides and an increased production of very-low density lipoproteins. Altogether, our results show that NS5A-D2 can reprogram central carbon metabolism towards a more energetic and glycolytic phenotype compatible with HCV needs for replication.
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Bunz M, Ritter M, Schindler M. HCV egress - unconventional secretion of assembled viral particles. Trends Microbiol 2021; 30:364-378. [PMID: 34483048 DOI: 10.1016/j.tim.2021.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/11/2021] [Accepted: 08/13/2021] [Indexed: 12/15/2022]
Abstract
It is believed that hepatitis C virus (HCV) particles are released through the canonical secretory route: from the endoplasmic reticulum (ER), via the Golgi, to the plasma membrane. While the Golgi is important for HCV release per se, its direct involvement in the trafficking of assembled virions has not yet been established. In fact, data from studies analyzing HCV egress are compatible with several potential pathways of HCV secretion. Here, we summarize and discuss the current knowledge related to the HCV export pathway. Apart from the prototypical anterograde transport, possible routes of HCV release include ER-to-endosomal transport, secretory autophagy, and poorly described mechanisms of unconventional protein secretion. Studying HCV egress promises to shed light on unconventional cellular trafficking and secretory routes.
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Affiliation(s)
- Maximilian Bunz
- Section Molecular Virology, Institute for Medical Virology and Epidemiology, University Hospital Tübingen, Tübingen, Germany
| | - Michael Ritter
- Section Molecular Virology, Institute for Medical Virology and Epidemiology, University Hospital Tübingen, Tübingen, Germany
| | - Michael Schindler
- Section Molecular Virology, Institute for Medical Virology and Epidemiology, University Hospital Tübingen, Tübingen, Germany.
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Shen M, Xu M, Zhong F, Crist MC, Prior AB, Yang K, Allaire DM, Choueiry F, Zhu J, Shi H. A Multi-Omics Study Revealing the Metabolic Effects of Estrogen in Liver Cancer Cells HepG2. Cells 2021; 10:cells10020455. [PMID: 33672651 PMCID: PMC7924215 DOI: 10.3390/cells10020455] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/14/2021] [Accepted: 02/16/2021] [Indexed: 12/19/2022] Open
Abstract
Hepatocellular carcinoma (HCC) that is triggered by metabolic defects is one of the most malignant liver cancers. A much higher incidence of HCC among men than women suggests the protective roles of estrogen in HCC development and progression. To begin to understand the mechanisms involving estrogenic metabolic effects, we compared cell number, viability, cytotoxicity, and apoptosis among HCC-derived HepG2 cells that were treated with different concentrations of 2-deoxy-d-glucose (2-DG) that blocks glucose metabolism, oxamate that inhibits lactate dehydrogenase and glycolysis, or oligomycin that blocks ATP synthesis and mitochondrial oxidative phosphorylation. We confirmed that HepG2 cells primarily utilized glycolysis followed by lactate fermentation, instead of mitochondrial oxidative phosphorylation, for cell growth. We hypothesized that estrogen altered energy metabolism via its receptors to carry out its anticancer effects in HepG2 cells. We treated cells with 17β-estradiol (E2), 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) an estrogen receptor (ER) α (ERα) agonist, or 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN), an ERβ agonist. We then used transcriptomic and metabolomic analyses and identified differentially expressed genes and unique metabolite fingerprints that are produced by each treatment. We further performed integrated multi-omics analysis, and identified key genes and metabolites in the gene–metabolite interaction contributed by E2 and ER agonists. This integrated transcriptomic and metabolomic study suggested that estrogen acts on estrogen receptors to suppress liver cancer cell growth via altering metabolism. This is the first exploratory study that comprehensively investigated estrogen and its receptors, and their roles in regulating gene expression, metabolites, metabolic pathways, and gene–metabolite interaction in HCC cells using bioinformatic tools. Overall, this study provides potential therapeutic targets for future HCC treatment.
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Affiliation(s)
- Minqian Shen
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
| | - Mengyang Xu
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; (F.Z.); (K.Y.)
| | - Fanyi Zhong
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; (F.Z.); (K.Y.)
| | - McKenzie C. Crist
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
| | - Anjali B. Prior
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
| | - Kundi Yang
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; (F.Z.); (K.Y.)
| | - Danielle M. Allaire
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
| | - Fouad Choueiry
- Department of Human Sciences, College of Education and Human Ecology, Columbus, OH 43210, USA;
- James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
| | - Jiangjiang Zhu
- Department of Human Sciences, College of Education and Human Ecology, Columbus, OH 43210, USA;
- James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
- Correspondence: (J.Z.); (H.S.); Tel.: +1-614-685-2226 (J.Z.); +1-513-529-3162 (H.S.)
| | - Haifei Shi
- Department of Biology, Miami University, Oxford, OH 45056, USA; (M.S.); (M.X.); (M.C.C.); (A.B.P.); (D.M.A.)
- Correspondence: (J.Z.); (H.S.); Tel.: +1-614-685-2226 (J.Z.); +1-513-529-3162 (H.S.)
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Cosset FL, Mialon C, Boson B, Granier C, Denolly S. HCV Interplay with Lipoproteins: Inside or Outside the Cells? Viruses 2020; 12:v12040434. [PMID: 32290553 PMCID: PMC7232430 DOI: 10.3390/v12040434] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/05/2020] [Accepted: 04/10/2020] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) infection is a major public health issue leading to chronic liver diseases. HCV particles are unique owing to their particular lipid composition, namely the incorporation of neutral lipids and apolipoproteins. The mechanism of association between HCV virion components and these lipoproteins factors remains poorly understood as well as its impact in subsequent steps of the viral life cycle, such as entry into cells. It was proposed that the lipoprotein biogenesis pathway is involved in HCV morphogenesis; yet, recent evidence indicated that HCV particles can mature and evolve biochemically in the extracellular medium after egress. In addition, several viral, cellular and blood components have been shown to influence and regulate this specific association. Finally, this specific structure and composition of HCV particles was found to influence entry into cells as well as their stability and sensitivity to neutralizing antibodies. Due to its specific particle composition, studying the association of HCV particles with lipoproteins remains an important goal towards the rational design of a protective vaccine.
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Plissonnier ML, Cottarel J, Piver E, Kullolli M, Centonze FG, Pitteri S, Farhan H, Meunier JC, Zoulim F, Parent R. LARP1 binding to hepatitis C virus particles is correlated with intracellular retention of viral infectivity. Virus Res 2019; 271:197679. [PMID: 31398365 DOI: 10.1016/j.virusres.2019.197679] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 07/27/2019] [Indexed: 12/23/2022]
Abstract
Hepatitis C virus (HCV) virions contain a subset of host liver cells proteome often composed of interesting virus-interacting factors. A proteomic analysis performed on double gradient-purified clinical HCV highlighted the translation regulator LARP1 on these virions. This finding was validated using post-virion capture and immunoelectron microscopy, as well as immunoprecipitation applied to in vitro (Huh7.5 liver cells) grown (Gt2a, JFH1 strain) and patient-derived (Gt1a) HCV particles. Upon HCV infection of Huh7.5 cells, we observed a drastic transfer of LARP1 to lipid droplets, inducing colocalization with core proteins. RNAi-mediated depletion of LARP1 using the C911 control approach decreased extracellular infectivity of HCV Gt1a (H77), Gt2a (JFH1), and Gt3a (S52 chimeric strain), yet increased their intracellular infectivity. This latter effect was unrelated to changes in the hepatocyte secretory pathway, as evidenced using a functional RUSH assay. These results indicate that LARP1 binds to HCV, an event associated with retention of intracellular infectivity.
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Affiliation(s)
- Marie-Laure Plissonnier
- Pathogenesis of Hepatitis B and C -DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, F-69008, Lyon, France
| | - Jessica Cottarel
- Pathogenesis of Hepatitis B and C -DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, F-69008, Lyon, France
| | - Eric Piver
- Morphogenesis and Antigenicity of HIV and Hepatitis Viruses, INSERM U966, Université de Tours, F-37000, Tours, France
| | - Majlinda Kullolli
- Canary Center for Cancer Early Detection, Department of Radiology, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | | | - Sharon Pitteri
- Canary Center for Cancer Early Detection, Department of Radiology, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Hesso Farhan
- Institute of Basic Medical Science, University of Oslo, N-0372, Olso, Norway
| | - Jean-Christophe Meunier
- Morphogenesis and Antigenicity of HIV and Hepatitis Viruses, INSERM U966, Université de Tours, F-37000, Tours, France
| | - Fabien Zoulim
- Pathogenesis of Hepatitis B and C -DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, F-69008, Lyon, France; Lyon University Hospital (Hospices civils de Lyon), Hepatogastroenterology Service, F-69001, Lyon, France
| | - Romain Parent
- Pathogenesis of Hepatitis B and C -DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, F-69008, Lyon, France.
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A serum protein factor mediates maturation and apoB-association of HCV particles in the extracellular milieu. J Hepatol 2019; 70:626-638. [PMID: 30553840 DOI: 10.1016/j.jhep.2018.11.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 11/15/2018] [Accepted: 11/30/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS In the sera of infected patients, hepatitis C virus (HCV) particles display heterogeneous forms with low-buoyant densities (<1.08), underscoring their lipidation via association with apoB-containing lipoproteins, which was proposed to occur during assembly or secretion from infected hepatocytes. However, the mechanisms inducing this association remain poorly-defined and most cell culture grown HCV (HCVcc) particles exhibit higher density (>1.08) and poor/no association with apoB. We aimed to elucidate the mechanisms of lipidation and to produce HCVcc particles resembling those in infected sera. METHODS We produced HCVcc particles of Jc1 or H77 strains from Huh-7.5 hepatoma cells cultured in standard conditions (10%-fetal calf serum) vs. in serum-free or human serum conditions before comparing their density profiles to patient-derived virus. We also characterized wild-type and Jc1/H77 hypervariable region 1 (HVR1)-swapped mutant HCVcc particles produced in serum-free media and incubated with different serum types or with purified lipoproteins. RESULTS Compared to serum-free or fetal calf serum conditions, production with human serum redistributed most HCVcc infectious particles to low density (<1.08) or very-low density (<1.04) ranges. In addition, short-time incubation with human serum was sufficient to shift HCVcc physical particles to low-density fractions, in time- and dose-dependent manners, which increased their specific infectivity, promoted apoB-association and induced neutralization-resistance. Moreover, compared to Jc1, we detected higher levels of H77 HCVcc infectious particles in very-low-density fractions, which could unambiguously be attributed to strain-specific features of the HVR1 sequence. Finally, all 3 lipoprotein classes, i.e., very-low-density, low-density and high-density lipoproteins, could synergistically induce low-density shift of HCV particles; yet, this required additional non-lipid serum factor(s) that include albumin. CONCLUSIONS The association of HCV particles with lipids may occur in the extracellular milieu. The lipidation level depends on serum composition as well as on HVR1-specific properties. These simple culture conditions allow production of infectious HCV particles resembling those of chronically-infected patients. LAY SUMMARY Hepatitis C virus (HCV) particles may associate with apoB and acquire neutral lipids after exiting cells, giving them low-buoyant density. The hypervariable region 1 (HVR1) is a majorviral determinant of E2 that controls this process. Besides lipoproteins, specific serum factors including albumin promote extracellular maturation of HCV virions. HCV particle production in vitro, with media of defined serum conditions, enables production of infectious particles resembling those of chronically infected patients.
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Abstract
Apolipoprotein E (apoE) plays dual functions in the HCV life cycle by promoting HCV infection and virion assembly and production. ApoE is a structural component on the HCV envelope. It mediates HCV cell attachment through specific interactions with the cell surface receptors such as syndecan-1 (SDC-1) and SDC-2 heparan sulfate proteoglycans (HSPGs). It also interacts with NS5A and E2, resulting in an enhancement of HCV morphogenesis. It can bind HCV extracellularly and promotes HCV infection. It is critical for HCV cell-to-cell transmission and may also play a role in HCV persistence by interfering with the action of HCV-neutralizing antibodies. Other apolipoproteins particularly apoB and apoC1 were also found on the HCV envelope, but their roles in the HCV life cycle remain unclear. In the last decade, a number of genomic, immunological, structural, and cell biology methodologies have been developed and used for determining the importance of apoE in the HCV life cycle. These methods and protocols will continue to be valuable to further understand the importance and the underlying molecular mechanism of various apolipoproteins in HCV infection and pathogenesis.
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Affiliation(s)
- Luhua Qiao
- Department of Microbiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
| | - Guangxiang George Luo
- Department of Microbiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA.
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Li YC, Zhang MQ, Zhang JP. Opposite Effects of Two Human ATG10 Isoforms on Replication of a HCV Sub-genomic Replicon Are Mediated via Regulating Autophagy Flux in Zebrafish. Front Cell Infect Microbiol 2018; 8:109. [PMID: 29670865 PMCID: PMC5893791 DOI: 10.3389/fcimb.2018.00109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 03/19/2018] [Indexed: 12/15/2022] Open
Abstract
Autophagy is a host mechanism for cellular homeostatic control. Intracellular stresses are symptoms of, and responses to, dysregulation of the physiological environment of the cell. Alternative gene transcription splicing is a mechanism potentially used by a host to respond to physiological or pathological challenges. Here, we aimed to confirm opposite effects of two isoforms of the human autophagy-related protein ATG10 on an HCV subgenomic replicon in zebrafish. A liver-specific HCV subreplicon model was established and exhibited several changes in gene expression typically induced by HCV infection, including overexpression of several HCV-dependent genes (argsyn, leugpcr, rasgbd, and scaf-2), as well as overexpression of several ER stress related genes (atf4, chop, atf6, and bip). Autophagy flux was blocked in the HCV model. Our results indicated that the replication of the HCV subreplicon was suppressed via a decrease in autophagosome formation caused by the autophagy inhibitor 3MA, but enhanced via dysfunction in the lysosomal degradation caused by another autophagy inhibitor CQ. Human ATG10, a canonical isoform in autophagy, facilitated the amplification of the HCV-subgenomic replicon via promoting autophagosome formation. ATG10S, a non-canonical short isoform of the ATG10 protein, promoted autophagy flux, leading to lysosomal degradation of the HCV-subgenomic replicon. Human ATG10S may therefore inhibit HCV replication, and may be an appropriate target for future antiviral drug screening.
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Affiliation(s)
- Yu-Chen Li
- Laboratory of Pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Miao-Qing Zhang
- Laboratory of Pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing-Pu Zhang
- Laboratory of Pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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10
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Bankwitz D, Doepke M, Hueging K, Weller R, Bruening J, Behrendt P, Lee JY, Vondran FWR, Manns MP, Bartenschlager R, Pietschmann T. Maturation of secreted HCV particles by incorporation of secreted ApoE protects from antibodies by enhancing infectivity. J Hepatol 2017; 67:480-489. [PMID: 28438690 DOI: 10.1016/j.jhep.2017.04.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 04/03/2017] [Accepted: 04/11/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS Hepatitis C virus (HCV) evades humoral immunity and establishes chronic infections. Virus particles circulate in complex with lipoproteins facilitating antibody escape. Apolipoprotein E (ApoE) is essential for intracellular HCV assembly and for HCV cell entry. We aimed to explore if ApoE released from non-infected cells interacts with and modulates secreted HCV particles. METHODS ApoE secreted from non-infected cells was incubated with HCV from primary human hepatocytes or Huh-7.5 cells. Co-immunoprecipitation, viral infectivity and neutralization experiments were conducted. RESULTS Physiological levels of secreted ApoE (10-60µg/ml) enhanced the infectivity of HCV up to 8-fold across all genotypes, which indirectly decreased virus neutralization by antibodies targeting E1 or E2 up to 10-fold. Infection enhancement was observed for particles produced in primary human hepatocytes and Huh-7.5 cells. Selective depletion of ApoE ablated infection enhancement. Addition of HA-tagged ApoE to HCV particles permitted co-precipitation of HCV virions. Serum ApoE levels ranged between 10-60µg/ml, which is ca 100-fold higher than in Huh-7.5 conditioned cell culture fluids. Serum-derived HCV particles carried much higher amounts of ApoE than cell culture-derived HCV particles. Serum ApoE levels correlated with efficiency of co-precipitation of HCV upon exogenous addition of HA-ApoE. ApoE-dependent infection enhancement was independent of the hypervariable region 1 and SR-B1, but was dependent on heparan sulfate proteoglycans (HSPGs). CONCLUSIONS Physiological quantities of secreted ApoE stimulate HCV infection and increase antibody escape, by incorporating into virus particles and enhancing particle interactions with cellular HSPGs. Thus, secreted particles undergo ApoE-dependent maturation to enhance infectivity and to facilitate evasion from neutralizing antibodies. Lay summary: This study shows that HCV particle infectivity is remodeled by secreted ApoE after particle release from cells. Fluctuation of the availability of ApoE likely influences HCV infectivity, antibody escape and transmission.
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Affiliation(s)
- Dorothea Bankwitz
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Mandy Doepke
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Kathrin Hueging
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Romy Weller
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Janina Bruening
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Patrick Behrendt
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany; Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
| | - Ji-Young Lee
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Florian W R Vondran
- Regenerative Medicine & Experimental Surgery (ReMediES), Department of General, Visceral and Transplant Surgery, Hannover Medical School, Germany; German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 30625 Hannover, Germany
| | - Michael P Manns
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 30625 Hannover, Germany; Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany; Division of Virus-Associated Carcinogenesis, German Cancer Research Center (DKFZ), Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg University, Heidelberg, Germany
| | - Thomas Pietschmann
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; a Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany; German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 30625 Hannover, Germany.
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11
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Entry and Release of Hepatitis C Virus in Polarized Human Hepatocytes. J Virol 2017; 91:JVI.00478-17. [PMID: 28659476 DOI: 10.1128/jvi.00478-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 06/22/2017] [Indexed: 12/23/2022] Open
Abstract
Hepatitis C virus (HCV) primarily infects hepatocytes, which are highly polarized cells. The relevance of cell polarity in the HCV life cycle has been addressed only in distantly related models and remains poorly understood. Although polarized epithelial cells have a rather simple morphology with a basolateral and an apical domain, hepatocytes exhibit complex polarization structures. However, it has been reported that some selected polarized HepG2 cell clones can exhibit a honeycomb pattern of distribution of the tight-junction proteins typical of columnar polarized epithelia, which can be used as a simple model to study the role of cell polarization in viral infection of hepatocytes. To obtain similar clones, HepG2 cells expressing CD81 (HepG2-CD81) were used, and clones were isolated by limiting dilutions. Two clones exhibiting a simple columnar polarization capacity when grown on a semipermeable support were isolated and characterized. To test the polarity of HCV entry and release, our polarized HepG2-CD81 clones were infected with cell culture-derived HCV. Our data indicate that HCV binds equally to both sides of the cells, but productive infection occurs mainly when the virus is added at the basolateral domain. Furthermore, we also observed that HCV virions are released from the basolateral domain of the cells. Finally, when polarized cells were treated with oleic acid and U0126, a MEK inhibitor, to promote lipoprotein secretion, a higher proportion of infectious viral particles of lower density were secreted. This cell culture system provides an excellent model to investigate the influence of cell polarization on the HCV life cycle.IMPORTANCE Hepatitis C is a major health burden, with approximately 170 million persons infected worldwide. Hepatitis C virus (HCV) primarily infects hepatocytes, which are highly polarized cells with a complex organization. The relevance of cell polarity in the HCV life cycle has been addressed in distantly related models and remains unclear. Hepatocyte organization is complex, with multiple apical and basolateral surfaces. A simple culture model of HepG2 cells expressing CD81 that are able to polarize with unique apical and basolateral domains was developed to study HCV infection. With this model, we demonstrated that HCV enters and exits hepatocytes by the basolateral domain. Furthermore, lower-density viral particles were produced under conditions that promote lipoprotein secretion. This cell culture system provides a useful model to study the influence of cell polarization on HCV infection.
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12
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Crouchet E, Baumert TF, Schuster C. Hepatitis C virus-apolipoprotein interactions: molecular mechanisms and clinical impact. Expert Rev Proteomics 2017; 14:593-606. [PMID: 28625086 PMCID: PMC6138823 DOI: 10.1080/14789450.2017.1344102] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Chronic hepatitis C virus (HCV) infection is a leading cause of cirrhosis, hepatocellular carcinoma and liver failure. Moreover, chronic HCV infection is associated with liver steatosis and metabolic disorders. With 130-150 million people chronically infected in the world, HCV infection represents a major public health problem. One hallmark on the virus is its close link with hepatic lipid and lipoprotein metabolism. Areas covered: HCV is associated with lipoprotein components such as apolipoproteins. These interactions play a key role in the viral life cycle, viral persistence and pathogenesis of liver disease. This review introduces first the role of apolipoproteins in lipoprotein metabolism, then highlights the molecular mechanisms of HCV-lipoprotein interactions and finally discusses their clinical impact. Expert commentary: While the study of virus-host interactions has resulted in a improvement of the understanding of the viral life cycle and the development of highly efficient therapies, major challenges remain: access to therapy is limited and an urgently needed HCV vaccine remains still elusive. Furthermore, the pathogenesis of disease biology is still only partially understood. The investigation of HCV-lipoproteins interactions offers new perspectives for novel therapeutic approaches, contribute to HCV vaccine design and understand virus-induced liver disease and cancer.
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Affiliation(s)
- Emilie Crouchet
- Inserm, U1110: Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Thomas F. Baumert
- Inserm, U1110: Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- Pôle hépato-digestif, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Catherine Schuster
- Inserm, U1110: Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
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13
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Sarhan MA, Abdel-Hakeem MS, Mason AL, Tyrrell DL, Houghton M. Glycogen synthase kinase 3β inhibitors prevent hepatitis C virus release/assembly through perturbation of lipid metabolism. Sci Rep 2017; 7:2495. [PMID: 28566716 PMCID: PMC5451429 DOI: 10.1038/s41598-017-02648-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/28/2017] [Indexed: 12/14/2022] Open
Abstract
Direct acting antivirals against hepatitis C virus (HCV) have markedly improved cure rates in the past few years. However, they are expensive, with only few targeting host cell factors, and affecting virus assembly and release. Huh7.5 cells infected with a JFH-1 clone of HCV were treated with two different glycogen synthase kinase (GSK3)-β inhibitors; AR-A014418 and lithium chloride. Intra- and extracellular HCV virions and specific infectivity was determined using real-time RT-PCR and TCID50, and changes in lipid production were identified by enzyme-linked immunoassay and mass spectrometry analyses. Similarly, effect on two HCV replicon cells were identified by the luciferase activity. Although there was limited effect on virus replication in Huh7.5 cells and replicons, Huh7.5 cells treated with GSK3β inhibitors produced significantly less viral particles in comparison to untreated cells. In addition, the treated cells synthesized significantly lower amounts of ApoB and trapped the ApoE lipoproteins in the cells. In conclusion, our study suggests that GSK3β plays a pivotal role in HCV virion assembly and release mediated in part through inhibition of apolipoprotein synthesis.
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Affiliation(s)
- Mohammed A Sarhan
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada. .,Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada. .,Department of Microbiology and Immunology, National Liver Institute, Menoufia University, Menoufia, Egypt. .,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
| | - Mohamed S Abdel-Hakeem
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada.,Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Andrew L Mason
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - D Lorne Tyrrell
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada
| | - Michael Houghton
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada
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14
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Grigorov B, Reungoat E, Gentil Dit Maurin A, Varbanov M, Blaising J, Michelet M, Manuel R, Parent R, Bartosch B, Zoulim F, Ruggiero F, Pécheur EI. Hepatitis C virus infection propagates through interactions between Syndecan-1 and CD81 and impacts the hepatocyte glycocalyx. Cell Microbiol 2017; 19:e12711. [PMID: 27930836 DOI: 10.1111/cmi.12711] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 12/17/2022]
Abstract
The hepatitis C virus (HCV) infects hepatocytes after binding to heparan sulfate proteoglycans, in particular Syndecan-1, followed by recognition of the tetraspanin CD81 and other receptors. Heparan sulfate proteoglycans are found in a specific microenvironment coating the hepatocyte surface called the glycocalyx and are receptors for extracellular matrix proteins, cytokines, growth factors, lipoproteins, and infectious agents. We investigated the mutual influence of HCV infection on the glycocalyx and revealed new links between Syndecan-1 and CD81. Hepatocyte infection by HCV was inhibited after knocking down Syndecan-1 or Xylosyltransferase 2, a key enzyme of Syndecan-1 biosynthesis. Simultaneous knockdown of Syndecan-1 and CD81 strongly inhibited infection, suggesting their cooperative action. At early infection stages, Syndecan-1 and virions colocalized at the plasma membrane and were internalized in endosomes. Direct interactions between Syndecan-1 and CD81 were revealed in primary and transformed hepatocytes by immunoprecipitation and proximity ligation assays. Expression of Syndecan-1 and Xylosyltransferase 2 was altered within days post-infection, and the remaining Syndecan-1 pool colocalized poorly with CD81. The data indicate a profound reshuffling of the hepatocyte glycocalyx during HCV infection, possibly required for establishing optimal conditions of viral propagation.
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Affiliation(s)
- Boyan Grigorov
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | - Emma Reungoat
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | | | | | - Julie Blaising
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | - Maud Michelet
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | - Rachel Manuel
- IGFL, ENS Lyon, CNRS UMR 5242, Université Lyon 1, France
| | - Romain Parent
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | - Birke Bartosch
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
| | - Fabien Zoulim
- CRCL, Inserm U1052, CNRS 5286, Université Lyon 1, France
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15
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Schaefer EAK, Meixiong J, Mark C, Deik A, Motola DL, Fusco D, Yang A, Brisac C, Salloum S, Lin W, Clish CB, Peng LF, Chung RT. Apolipoprotein B100 is required for hepatitis C infectivity and Mipomersen inhibits hepatitis C. World J Gastroenterol 2016; 22:9954-9965. [PMID: 28018102 PMCID: PMC5143762 DOI: 10.3748/wjg.v22.i45.9954] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/01/2016] [Accepted: 10/27/2016] [Indexed: 02/06/2023] Open
Abstract
AIM To characterize the role of apolipoprotein B100 (apoB100) in hepatitis C viral (HCV) infection.
METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases (TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDA-approved antisense inhibitor of apoB100, on HCV using in vitro cell-culture competent HCV and determined its impact on viral infectivity with the TCID50 method.
RESULTS We found that apoB100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALEN-mediated gene deletion of apoB (APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apoB did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wild-type virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus.
CONCLUSION ApoB is required for the generation of fully infectious HCV virions, and inhibition of apoB with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.
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16
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Santos AJM, Nogueira C, Ortega-Bellido M, Malhotra V. TANGO1 and Mia2/cTAGE5 (TALI) cooperate to export bulky pre-chylomicrons/VLDLs from the endoplasmic reticulum. J Cell Biol 2016; 213:343-54. [PMID: 27138255 PMCID: PMC4862334 DOI: 10.1083/jcb.201603072] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 04/14/2016] [Indexed: 01/04/2023] Open
Abstract
Santos et al. show that TANGO1 and a TANGO1-like protein, TALI, bind each other and function together as receptors to export bulky ApoB-containing lipid particles from the endoplasmic reticulum. However, TANGO1-mediated export of bulky collagens by the same cells is TALI independent. Procollagens, pre-chylomicrons, and pre–very low-density lipoproteins (pre-VLDLs) are too big to fit into conventional COPII-coated vesicles, so how are these bulky cargoes exported from the endoplasmic reticulum (ER)? We have shown that TANGO1 located at the ER exit site is necessary for procollagen export. We report a role for TANGO1 and TANGO1-like (TALI), a chimeric protein resulting from fusion of MIA2 and cTAGE5 gene products, in the export of pre-chylomicrons and pre-VLDLs from the ER. TANGO1 binds TALI, and both interact with apolipoprotein B (ApoB) and are necessary for the recruitment of ApoB-containing lipid particles to ER exit sites for their subsequent export. Although export of ApoB requires the function of both TANGO1 and TALI, the export of procollagen XII by the same cells requires only TANGO1. These findings reveal a general role for TANGO1 in the export of bulky cargoes from the ER and identify a specific requirement for TALI in assisting TANGO1 to export bulky lipid particles.
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Affiliation(s)
- António J M Santos
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain Universitat Pompeu Fabra, 08002 Barcelona, Spain
| | - Cristina Nogueira
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain Universitat Pompeu Fabra, 08002 Barcelona, Spain
| | - Maria Ortega-Bellido
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain Universitat Pompeu Fabra, 08002 Barcelona, Spain
| | - Vivek Malhotra
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain Universitat Pompeu Fabra, 08002 Barcelona, Spain Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
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17
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Fukuhara T, Ono C, Puig-Basagoiti F, Matsuura Y. Roles of Lipoproteins and Apolipoproteins in Particle Formation of Hepatitis C Virus. Trends Microbiol 2016; 23:618-629. [PMID: 26433694 DOI: 10.1016/j.tim.2015.07.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/07/2015] [Accepted: 07/20/2015] [Indexed: 02/06/2023]
Abstract
More than 160 million people worldwide are infected with hepatitis C virus (HCV), and cirrhosis and hepatocellular carcinoma induced by HCV infection are life-threatening diseases. HCV takes advantage of many aspects of lipid metabolism for an efficient propagation in hepatocytes. Due to the morphological and physiological similarities of HCV particles to lipoproteins, lipid-associated HCV particles are named lipoviroparticles. Recent analyses have revealed that exchangeable apolipoproteins directly interact with the viral membrane to generate infectious HCV particles. In this review, we summarize the roles of lipid metabolism in the life cycle of HCV.
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Affiliation(s)
- Takasuke Fukuhara
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Chikako Ono
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Francesc Puig-Basagoiti
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
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18
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Shen M, Shi H. Estradiol and Estrogen Receptor Agonists Oppose Oncogenic Actions of Leptin in HepG2 Cells. PLoS One 2016; 11:e0151455. [PMID: 26982332 PMCID: PMC4794158 DOI: 10.1371/journal.pone.0151455] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 02/28/2016] [Indexed: 11/19/2022] Open
Abstract
Obesity is a significant risk factor for certain cancers, including hepatocellular carcinoma (HCC). Leptin, a hormone secreted by white adipose tissue, precipitates HCC development. Epidemiology data show that men have a much higher incidence of HCC than women, suggesting that estrogens and its receptors may inhibit HCC development and progression. Whether estrogens antagonize oncogenic action of leptin is uncertain. To investigate potential inhibitory effects of estrogens on leptin-induced HCC development, HCC cell line HepG2 cells were treated with leptin in combination with 17 β-estradiol (E2), estrogen receptor-α (ER-α) selective agonist PPT, ER-β selective agonist DPN, or G protein-coupled ER (GPER) selective agonist G-1. Cell number, proliferation, and apoptosis were determined, and leptin- and estrogen-related intracellular signaling pathways were analyzed. HepG2 cells expressed a low level of ER-β mRNA, and leptin treatment increased ER-β expression. E2 suppressed leptin-induced HepG2 cell proliferation and promoted cell apoptosis in a dose-dependent manner. Additionally E2 reversed leptin-induced STAT3 and leptin-suppressed SOCS3, which was mainly achieved by activation of ER-β. E2 also enhanced ERK via activating ER-α and GPER and activated p38/MAPK via activating ER-β. To conclude, E2 and its receptors antagonize the oncogenic actions of leptin in HepG2 cells by inhibiting cell proliferation and stimulating cell apoptosis, which was associated with reversing leptin-induced changes in SOCS3/STAT3 and increasing p38/MAPK by activating ER-β, and increasing ERK by activating ER-α and GPER. Identifying roles of different estrogen receptors would provide comprehensive understanding of estrogenic mechanisms in HCC development and shed light on potential treatment for HCC patients.
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Affiliation(s)
- Minqian Shen
- Department of Biology, Cell, Molecular, and Structural Biology, Miami University, Oxford, Ohio, United States of America
| | - Haifei Shi
- Department of Biology, Cell, Molecular, and Structural Biology, Miami University, Oxford, Ohio, United States of America
- * E-mail:
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19
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Grassi G, Di Caprio G, Fimia GM, Ippolito G, Tripodi M, Alonzi T. Hepatitis C virus relies on lipoproteins for its life cycle. World J Gastroenterol 2016; 22:1953-1965. [PMID: 26877603 PMCID: PMC4726671 DOI: 10.3748/wjg.v22.i6.1953] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/19/2015] [Accepted: 12/21/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) infects over 150 million people worldwide. In most cases, HCV infection becomes chronic causing liver disease ranging from fibrosis to cirrhosis and hepatocellular carcinoma. Viral persistence and pathogenesis are due to the ability of HCV to deregulate specific host processes, mainly lipid metabolism and innate immunity. In particular, HCV exploits the lipoprotein machineries for almost all steps of its life cycle. The aim of this review is to summarize current knowledge concerning the interplay between HCV and lipoprotein metabolism. We discuss the role played by members of lipoproteins in HCV entry, replication and virion production.
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20
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Brault C, Lévy P, Duponchel S, Michelet M, Sallé A, Pécheur EI, Plissonnier ML, Parent R, Véricel E, Ivanov AV, Demir M, Steffen HM, Odenthal M, Zoulim F, Bartosch B. Glutathione peroxidase 4 is reversibly induced by HCV to control lipid peroxidation and to increase virion infectivity. Gut 2016; 65:144-54. [PMID: 25516417 DOI: 10.1136/gutjnl-2014-307904] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 11/19/2014] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Inflammation and oxidative stress drive disease progression in chronic hepatitis C (CHC) towards hepatocellular carcinoma. HCV is known to increase intracellular levels of reactive oxygen species (ROS), but how it eliminates ROS is less well known. The role of the ROS scavenger glutathione peroxidase 4 (GPx4), induced by HCV, in the viral life cycle was analysed. DESIGN The study was performed using a replicative in vitro HCV infection model and liver biopsies derived from two different CHC patient cohorts. RESULTS A screen for HCV-induced peroxide scavengers identified GPx4 as a host factor required for HCV infection. The physiological role of GPx4 is the elimination of lipid peroxides from membranes or lipoproteins. GPx4-silencing reduced the specific infectivity of HCV by up to 10-fold. Loss of infectivity correlated with 70% reduced fusogenic activity of virions in liposome fusion assays. NS5A was identified as the protein that mediates GPx4 induction in a phosphatidylinositol-3-kinase-dependent manner. Levels of GPx4 mRNA were found increased in vitro and in CHC compared with control liver biopsies. Upon successful viral eradication, GPx4 transcript levels returned to baseline in vitro and also in the liver of patients. CONCLUSIONS HCV induces oxidative stress but controls it tightly by inducing ROS scavengers. Among these, GPx4 plays an essential role in the HCV life cycle. Modulating oxidative stress in CHC by specifically targeting GPx4 may lower specific infectivity of virions and prevent hepatocarcinogenesis, especially in patients who remain difficult to be treated in the new era of interferon-free regimens.
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Affiliation(s)
- Charlène Brault
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France
| | - Pierre Lévy
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France
| | - Sarah Duponchel
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France
| | - Maud Michelet
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France
| | - Aurèlie Sallé
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France
| | | | | | - Romain Parent
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France DevWeCan Laboratories of Excellence Network (Labex), France
| | - Evelyne Véricel
- Université de Lyon, UMR 1060 INSERM CarMeN, IMBL, INSA-Lyon, Lyon, France
| | - Alexander V Ivanov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Münevver Demir
- Clinic for Gastroenterology and Hepatology, University Hospital of Cologne, Cologne, Germany
| | - Hans-Michael Steffen
- Clinic for Gastroenterology and Hepatology, University Hospital of Cologne, Cologne, Germany
| | | | - Fabien Zoulim
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France DevWeCan Laboratories of Excellence Network (Labex), France Hospices civils de Lyon, Lyon, France
| | - Birke Bartosch
- Inserm U1052, Cancer Research Center of Lyon, University of Lyon, Lyon, France DevWeCan Laboratories of Excellence Network (Labex), France
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Luangsay S, Ait-Goughoulte M, Michelet M, Floriot O, Bonnin M, Gruffaz M, Rivoire M, Fletcher S, Javanbakht H, Lucifora J, Zoulim F, Durantel D. Expression and functionality of Toll- and RIG-like receptors in HepaRG cells. J Hepatol 2015; 63:1077-85. [PMID: 26144659 DOI: 10.1016/j.jhep.2015.06.022] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 06/15/2015] [Accepted: 06/16/2015] [Indexed: 12/23/2022]
Abstract
BACKGROUND & AIMS HepaRG cells are considered as the best surrogate model to primary human hepatocyte (PHH) culture to investigate host-pathogen interactions. Yet their innate immune functions remain unknown. In this study, we explored the expression and functionality of Toll-like (TLR) and retinoic acid-inducible gene-1 (RIG-I)-like receptors (RLR) in these cells. METHODS Gene and protein expression levels of TLR-1 to 9 and RLR in HepaRG were mainly compared to PHH, by RT-qPCR, FACS, and Western blotting. Their functionality was assessed, by measuring the induction of toll/rig-like themselves and several target innate gene expressions, as well as the secretion of IL-6, IP-10, and type I interferon (IFN), upon agonist stimulation. Their functionality was also shown by measuring the antiviral activity of some TLR/RLR agonists against hepatitis B virus (HBV) infection. RESULTS The basal gene and protein expression profile of TLR/RLR in HepaRG cells was similar to PHH. Most receptors, except for TLR-7 and 9, were expressed as proteins and functionally active as shown by the induction of some innate genes, as well as by the secretion of IL-6 and IP-10, upon agonist stimulation. The highest levels of IL-6 and IP-10 secretion were obtained by TLR-2 and TLR-3 agonist stimulation respectively. The highest preventive anti-HBV activity was obtained following TLR-2, TLR-4 or RIG-I/MDA-5 stimulations, which correlated with their high capacity to produce both cytokines. CONCLUSIONS Our results indicate that HepaRG cells express a similar pattern of functional TLR/RLR as compared to PHH, thus qualifying HepaRG cells as a surrogate model to study pathogen interactions within a hepatocyte innate system.
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Affiliation(s)
- Souphalone Luangsay
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland
| | - Malika Ait-Goughoulte
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland
| | - Maud Michelet
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France
| | - Océane Floriot
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France
| | - Marc Bonnin
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France
| | - Marion Gruffaz
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France
| | - Michel Rivoire
- Centre Léon Bérard (CLB), 69008 Lyon, France; INSERM U1032, 69003 Lyon, France
| | - Simon Fletcher
- Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland
| | - Hassan Javanbakht
- Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland
| | - Julie Lucifora
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France
| | - Fabien Zoulim
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Hospices Civils de Lyon (HCL), 69002 Lyon, France; Institut Universitaire de France (IUF), 75005 Paris, France.
| | - David Durantel
- INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
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Cottarel J, Plissonnier ML, Kullolli M, Pitteri S, Clément S, Millarte V, Si-Ahmed SN, Farhan H, Zoulim F, Parent R. FIG4 is a hepatitis C virus particle-bound protein implicated in virion morphogenesis and infectivity with cholesteryl ester modulation potential. J Gen Virol 2015; 97:69-81. [PMID: 26519381 DOI: 10.1099/jgv.0.000331] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
There is growing evidence that virus particles also contain host cell proteins, which provide viruses with certain properties required for entry and release. A proteomic analysis performed on double-gradient-purified hepatitis C virus (HCV) from two highly viraemic patients identified the phosphatidylinositol 3,5-bisphosphate 5-phosphatase FIG4 (KIAA0274) as part of the viral particles. We validated the association using immunoelectron microscopy, immunoprecipitation and neutralization assays in vitro as well as patient-derived virus particles. RNA interference-mediated reduction of FIG4 expression decreased cholesteryl ester (CE) levels along with intra- and extracellular viral infectivity without affecting HCV RNA levels. Likewise, overexpressing FIG4 increased intracellular CE levels as well as intra- and extracellular viral infectivity without affecting viral RNA levels. Triglyceride levels and lipid droplet (LD) parameters remained unaffected. The 3,5-bisphosphate 5-phosphatase active site of FIG4 was found to strongly condition these results. Whilst FIG4 was found to localize to areas corresponding to viral assembly sites, at the immediate vicinity of LDs in calnexin-positive and HCV core-positive regions, no implication of FIG4 in the secretory pathway of the hepatocytes could be found using either FIG4-null mice, in vitro morphometry or functional assays of the ERGIC/Golgi compartments. This indicates that FIG4-dependent modulation of HCV infectivity is unrelated to alterations in the functionality of the secretory pathway. As a result of the documented implication of CE in the composition and infectivity of HCV particles, these results suggest that FIG4 binds to HCV and modulates particle formation in a CE-related manner.
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Affiliation(s)
- Jessica Cottarel
- Pathogenesis of Hepatitis B and C - DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, 69008 Lyon, France
| | - Marie-Laure Plissonnier
- Pathogenesis of Hepatitis B and C - DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, 69008 Lyon, France
| | - Majlinda Kullolli
- Canary Center for Cancer Early Detection, Department of Radiology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Sharon Pitteri
- Canary Center for Cancer Early Detection, Department of Radiology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Sophie Clément
- Department of Clinical Pathology, University of Geneva, Geneva, Switzerland
| | | | | | - Hesso Farhan
- Department of Biology, University of Konstanz, Germany.,Hôpital d'Orléans, 45000 Orléans, France
| | - Fabien Zoulim
- Pathogenesis of Hepatitis B and C - DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, 69008 Lyon, France.,Hospices Civils de Lyon, Service d'Hépatogastroentérologie, 69001 Lyon, France
| | - Romain Parent
- Pathogenesis of Hepatitis B and C - DEVweCAN LabEx, INSERM U1052-CNRS 5286, Centre de Recherche en Cancérologie de Lyon, Université de Lyon, 69008 Lyon, France
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23
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Calattini S, Fusil F, Mancip J, Dao Thi VL, Granier C, Gadot N, Scoazec JY, Zeisel MB, Baumert TF, Lavillette D, Dreux M, Cosset FL. Functional and Biochemical Characterization of Hepatitis C Virus (HCV) Particles Produced in a Humanized Liver Mouse Model. J Biol Chem 2015; 290. [PMID: 26224633 PMCID: PMC4645586 DOI: 10.1074/jbc.m115.662999] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Lipoprotein components are crucial factors for hepatitis C virus (HCV) assembly and entry. As hepatoma cells producing cell culture-derived HCV (HCVcc) particles are impaired in some aspects of lipoprotein metabolism, it is of upmost interest to biochemically and functionally characterize the in vivo produced viral particles, particularly regarding how lipoprotein components modulate HCV entry by lipid transfer receptors such as scavenger receptor BI (SR-BI). Sera from HCVcc-infected liver humanized FRG mice were separated by density gradients. Viral subpopulations, termed HCVfrg particles, were characterized for their physical properties, apolipoprotein association, and infectivity. We demonstrate that, in contrast to the widely spread distribution of apolipoproteins across the different HCVcc subpopulations, the most infectious HCVfrg particles are highly enriched in apoE, suggesting that such apolipoprotein enrichment plays a role for entry of in vivo derived infectious particles likely via usage of apolipoprotein receptors. Consistent with this salient feature, we further reveal previously undefined functionalities of SR-BI in promoting entry of in vivo produced HCV. First, unlike HCVcc, SR-BI is a particularly limiting factor for entry of HCVfrg subpopulations of very low density. Second, HCVfrg entry involves SR-BI lipid transfer activity but not its capacity to bind to the viral glycoprotein E2. In conclusion, we demonstrate that composition and biophysical properties of the different subpopulations of in vivo produced HCVfrg particles modulate their levels of infectivity and receptor usage, hereby featuring divergences with in vitro produced HCVcc particles and highlighting the powerfulness of this in vivo model for the functional study of the interplay between HCV and liver components.
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Affiliation(s)
| | | | | | | | | | - Nicolas Gadot
- Structure Fédérative de Recherche (SFR) Lyon-Est, ANIPATH-Centre d'Histopathologie du Petit Animal de laboratoire, CNRS UMS3453-INSERM US7, 69372 Lyon, France
| | - Jean-Yves Scoazec
- Structure Fédérative de Recherche (SFR) Lyon-Est, ANIPATH-Centre d'Histopathologie du Petit Animal de laboratoire, CNRS UMS3453-INSERM US7, 69372 Lyon, France
| | - Mirjam B Zeisel
- INSERM, U1110, Institut des Maladies Virales et Hépatiques, 67000 Strasbourg, France, University of Strasbourg, 67000 Strasbourg, France, and
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24
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Apolipoprotein E, but Not Apolipoprotein B, Is Essential for Efficient Cell-to-Cell Transmission of Hepatitis C Virus. J Virol 2015. [PMID: 26202245 DOI: 10.1128/jvi.00577-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Hepatitis C virus (HCV) infects hepatocytes through two different routes: (i) cell-free particle diffusion followed by engagement with specific cellular receptors and (ii) cell-to-cell direct transmission mediated by mechanisms not well defined yet. HCV exits host cells in association with very-low-density lipoprotein (VLDL) components. VLDL particles contain apolipoproteins B (ApoB) and E (ApoE), which are required for viral assembly and/or infectivity. Based on these precedents, we decided to study whether these VLDL components participate in HCV cell-to-cell transmission in vitro. We observed that cell-to-cell viral spread was compromised after ApoE interference in donor but not in acceptor cells. In contrast, ApoB knockdown in either donor or acceptor cells did not impair cell-to-cell viral transmission. Interestingly, ApoB participated in the assembly of cell-free infective virions, suggesting a differential regulation of cell-to-cell and cell-free HCV infection. This study identifies host-specific factors involved in these distinct routes of infection that may unveil new therapeutic targets and advance our understanding of HCV pathogenesis. IMPORTANCE This work demonstrates that cell-to-cell transmission of HCV depends on ApoE but not ApoB. The data also indicate that ApoB is required for the assembly of cell-free infective particles, strongly suggesting the existence of mechanisms involving VLDL components that differentially regulate cell-free and cell-to-cell HCV transmission. These data clarify some of the questions regarding the role of VLDL in HCV pathogenesis and the transmission of the virus cell to cell as a possible mechanism of immune evasion and open the door to therapeutic intervention.
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25
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Nagiec MM, Skepner AP, Negri J, Eichhorn M, Kuperwasser N, Comer E, Muncipinto G, Subramanian A, Clish C, Musunuru K, Duvall JR, Foley M, Perez JR, Palmer MAJ. Modulators of hepatic lipoprotein metabolism identified in a search for small-molecule inducers of tribbles pseudokinase 1 expression. PLoS One 2015; 10:e0120295. [PMID: 25811180 PMCID: PMC4374785 DOI: 10.1371/journal.pone.0120295] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 01/28/2015] [Indexed: 12/04/2022] Open
Abstract
Recent genome wide association studies have linked tribbles pseudokinase 1 (TRIB1) to the risk of coronary artery disease (CAD). Based on the observations that increased expression of TRIB1 reduces secretion of VLDL and is associated with lower plasma levels of LDL cholesterol and triglycerides, higher plasma levels of HDL cholesterol and reduced risk for myocardial infarction, we carried out a high throughput phenotypic screen based on quantitative RT-PCR assay to identify compounds that induce TRIB1 expression in human HepG2 hepatoma cells. In a screen of a collection of diversity-oriented synthesis (DOS)-derived compounds, we identified a series of benzofuran-based compounds that upregulate TRIB1 expression and phenocopy the effects of TRIB1 cDNA overexpression, as they inhibit triglyceride synthesis and apoB secretion in cells. In addition, the compounds downregulate expression of MTTP and APOC3, key components of the lipoprotein assembly pathway. However, CRISPR-Cas9 induced chromosomal disruption of the TRIB1 locus in HepG2 cells, while confirming its regulatory role in lipoprotein metabolism, demonstrated that the effects of benzofurans persist in TRIB1-null cells indicating that TRIB1 is sufficient but not necessary to transmit the effects of the drug. Remarkably, active benzofurans, as well as natural products capable of TRIB1 upregulation, also modulate hepatic cell cholesterol metabolism by elevating the expression of LDLR transcript and LDL receptor protein, while reducing the levels of PCSK9 transcript and secreted PCSK9 protein and stimulating LDL uptake. The effects of benzofurans are not masked by cholesterol depletion and are independent of the SREBP-2 regulatory circuit, indicating that these compounds represent a novel class of chemically tractable small-molecule modulators that shift cellular lipoprotein metabolism in HepG2 cells from lipogenesis to scavenging.
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Affiliation(s)
- Marek M. Nagiec
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Adam P. Skepner
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Joseph Negri
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michelle Eichhorn
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Nicolas Kuperwasser
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Eamon Comer
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Giovanni Muncipinto
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Aravind Subramanian
- Cancer Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Clary Clish
- Metabolite Profiling Platform, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Kiran Musunuru
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Jeremy R. Duvall
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michael Foley
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Jose R. Perez
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michelle A. J. Palmer
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
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26
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Hepatitis C virus life cycle and lipid metabolism. BIOLOGY 2014; 3:892-921. [PMID: 25517881 PMCID: PMC4280516 DOI: 10.3390/biology3040892] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/04/2014] [Accepted: 12/08/2014] [Indexed: 12/12/2022]
Abstract
Hepatitis C Virus (HCV) infects over 150 million people worldwide. In most cases HCV infection becomes chronic, causing liver disease ranging from fibrosis to cirrhosis and hepatocellular carcinoma. HCV affects the cholesterol homeostasis and at the molecular level, every step of the virus life cycle is intimately connected to lipid metabolism. In this review, we present an update on the lipids and apolipoproteins that are involved in the HCV infectious cycle steps: entry, replication and assembly. Moreover, the result of the assembly process is a lipoviroparticle, which represents a peculiarity of hepatitis C virion. This review illustrates an example of an intricate virus-host interaction governed by lipid metabolism.
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27
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Amphipathic α-helices in apolipoproteins are crucial to the formation of infectious hepatitis C virus particles. PLoS Pathog 2014; 10:e1004534. [PMID: 25502789 PMCID: PMC4263759 DOI: 10.1371/journal.ppat.1004534] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 10/21/2014] [Indexed: 12/11/2022] Open
Abstract
Apolipoprotein B (ApoB) and ApoE have been shown to participate in the particle formation and the tissue tropism of hepatitis C virus (HCV), but their precise roles remain uncertain. Here we show that amphipathic α-helices in the apolipoproteins participate in the HCV particle formation by using zinc finger nucleases-mediated apolipoprotein B (ApoB) and/or ApoE gene knockout Huh7 cells. Although Huh7 cells deficient in either ApoB or ApoE gene exhibited slight reduction of particles formation, knockout of both ApoB and ApoE genes in Huh7 (DKO) cells severely impaired the formation of infectious HCV particles, suggesting that ApoB and ApoE have redundant roles in the formation of infectious HCV particles. cDNA microarray analyses revealed that ApoB and ApoE are dominantly expressed in Huh7 cells, in contrast to the high level expression of all of the exchangeable apolipoproteins, including ApoA1, ApoA2, ApoC1, ApoC2 and ApoC3 in human liver tissues. The exogenous expression of not only ApoE, but also other exchangeable apolipoproteins rescued the infectious particle formation of HCV in DKO cells. In addition, expression of these apolipoproteins facilitated the formation of infectious particles of genotype 1b and 3a chimeric viruses. Furthermore, expression of amphipathic α-helices in the exchangeable apolipoproteins facilitated the particle formation in DKO cells through an interaction with viral particles. These results suggest that amphipathic α-helices in the exchangeable apolipoproteins play crucial roles in the infectious particle formation of HCV and provide clues to the understanding of life cycle of HCV and the development of novel anti-HCV therapeutics targeting for viral assembly.
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28
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Hepatitis C virus and lipid droplets: finding a niche. Trends Mol Med 2014; 21:34-42. [PMID: 25496657 DOI: 10.1016/j.molmed.2014.11.003] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 11/11/2014] [Accepted: 11/17/2014] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) causes serious liver disease in chronically infected individuals. Infectious virions are released from hepatocytes as lipoprotein complexes, indicating that the virus interacts with very low density lipoprotein (VLDL) assembly to propagate. The primary source of lipid for incorporation into VLDL is cytoplasmic lipid droplets (LDs). This organelle is targeted by two virus-encoded proteins as part of a process essential for virion morphogenesis. Moreover, LDs regulate infection. A common condition in HCV-infected individuals is steatosis, characterized by an accumulation of LDs. The mechanisms underlying development of steatosis include direct effects of the virus on lipid metabolism. This review reveals new insights into HCV infection and a further twist to the growing list of functions performed by LDs.
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29
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Abstract
Hepatitis C virus (HCV) is a major global health burden accounting for around 170 million chronic infections worldwide. Although highly potent direct-acting antiviral drugs to treat chronic hepatitis C have been approved recently, owing to their high costs and limited availability and a large number of undiagnosed infections, the burden of disease is expected to rise in the next few years. In addition, HCV is an excellent paradigm for understanding the tight link between a pathogen and host cell pathways, most notably lipid metabolism. HCV extensively remodels intracellular membranes to establish its cytoplasmic replication factory and also usurps components of the intercellular lipid transport system for production of infectious virus particles. Here, we review the molecular mechanisms of viral replicase function, cellular pathways employed during HCV replication factory biogenesis, and viral, as well as cellular, determinants of progeny virus production.
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30
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Apolipoprotein E likely contributes to a maturation step of infectious hepatitis C virus particles and interacts with viral envelope glycoproteins. J Virol 2014; 88:12422-37. [PMID: 25122793 DOI: 10.1128/jvi.01660-14] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED The assembly of infectious hepatitis C virus (HCV) particles is tightly linked to components of the very-low-density lipoprotein (VLDL) pathway. We and others have shown that apolipoprotein E (ApoE) plays a major role in production of infectious HCV particles. However, the mechanism by which ApoE contributes to virion assembly/release and how it gets associated with the HCV particle is poorly understood. We found that knockdown of ApoE reduces titers of infectious intra- and extracellular HCV but not of the related dengue virus. ApoE depletion also reduced amounts of extracellular HCV core protein without affecting intracellular core amounts. Moreover, we found that ApoE depletion affected neither formation of nucleocapsids nor their envelopment, suggesting that ApoE acts at a late step of assembly, such as particle maturation and infectivity. Importantly, we demonstrate that ApoE interacts with the HCV envelope glycoproteins, most notably E2. This interaction did not require any other viral proteins and depended on the transmembrane domain of E2 that also was required for recruitment of HCV envelope glycoproteins to detergent-resistant membrane fractions. These results suggest that ApoE plays an important role in HCV particle maturation, presumably by direct interaction with viral envelope glycoproteins. IMPORTANCE The HCV replication cycle is tightly linked to host cell lipid pathways and components. This is best illustrated by the dependency of HCV assembly on lipid droplets and the VLDL component ApoE. Although the role of ApoE for production of infectious HCV particles is well established, it is still poorly understood how ApoE contributes to virion formation and how it gets associated with HCV particles. Here, we provide experimental evidence that ApoE likely is required for an intracellular maturation step of HCV particles. Moreover, we demonstrate that ApoE associates with the viral envelope glycoproteins. This interaction appears to be dispensable for envelopment of virus particles but likely contributes to the quality control of secreted infectious virions. These results shed new light on the exploitation of host cell lipid pathways by HCV and the link of viral particle assembly to the VLDL component ApoE.
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31
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Fletcher NF, Sutaria R, Jo J, Barnes A, Blahova M, Meredith LW, Cosset FL, Curbishley SM, Adams DH, Bertoletti A, McKeating JA. Activated macrophages promote hepatitis C virus entry in a tumor necrosis factor-dependent manner. Hepatology 2014; 59:1320-30. [PMID: 24259385 PMCID: PMC4255687 DOI: 10.1002/hep.26911] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 10/19/2013] [Indexed: 02/06/2023]
Abstract
UNLABELLED Macrophages are critical components of the innate immune response in the liver. Chronic hepatitis C is associated with immune infiltration and the infected liver shows a significant increase in total macrophage numbers; however, their role in the viral life cycle is poorly understood. Activation of blood-derived and intrahepatic macrophages with a panel of Toll-like receptor agonists induce soluble mediators that promote hepatitis C virus (HCV) entry into polarized hepatoma cells. We identified tumor necrosis factor α (TNF-α) as the major cytokine involved in this process. Importantly, this effect was not limited to HCV; TNF-α increased the permissivity of hepatoma cells to infection by Lassa, measles and vesicular stomatitis pseudoviruses. TNF-α induced a relocalization of tight junction protein occludin and increased the lateral diffusion speed of HCV receptor tetraspanin CD81 in polarized HepG2 cells, providing a mechanism for their increased permissivity to support HCV entry. High concentrations of HCV particles could stimulate macrophages to express TNF-α, providing a direct mechanism for the virus to promote infection. CONCLUSION This study shows a new role for TNF-α to increase virus entry and highlights the potential for HCV to exploit existing innate immune responses in the liver to promote de novo infection events.
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Affiliation(s)
- Nicola F Fletcher
- Hepatitis C Research Group, Institute for Biomedical Research, University of BirminghamBirmingham, UK
| | - Rupesh Sutaria
- NIHR Liver Biomedical Research Unit, University of BirminghamBirmingham, UK
| | - Juandy Jo
- Viral Hepatitis Laboratory, Singapore Institute for Clinical Sciences, Agency of Science Technology and Research (A*STAR)Singapore
| | - Amy Barnes
- Hepatitis C Research Group, Institute for Biomedical Research, University of BirminghamBirmingham, UK
| | - Miroslava Blahova
- NIHR Liver Biomedical Research Unit, University of BirminghamBirmingham, UK
| | - Luke W Meredith
- Hepatitis C Research Group, Institute for Biomedical Research, University of BirminghamBirmingham, UK
| | | | | | - David H Adams
- NIHR Liver Biomedical Research Unit, University of BirminghamBirmingham, UK
| | - Antonio Bertoletti
- Viral Hepatitis Laboratory, Singapore Institute for Clinical Sciences, Agency of Science Technology and Research (A*STAR)Singapore
| | - Jane A McKeating
- Hepatitis C Research Group, Institute for Biomedical Research, University of BirminghamBirmingham, UK,NIHR Liver Biomedical Research Unit, University of BirminghamBirmingham, UK
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32
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Apolipoprotein E codetermines tissue tropism of hepatitis C virus and is crucial for viral cell-to-cell transmission by contributing to a postenvelopment step of assembly. J Virol 2013; 88:1433-46. [PMID: 24173232 DOI: 10.1128/jvi.01815-13] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) predominantly infects human hepatocytes, although extrahepatic virus reservoirs are being discussed. Infection of cells is initiated via cell-free and direct cell-to-cell transmission routes. Cell type-specific determinants of HCV entry and RNA replication have been reported. Moreover, several host factors required for synthesis and secretion of lipoproteins from liver cells, in part expressed in tissue-specific fashion, have been implicated in HCV assembly. However, the minimal cell type-specific requirements for HCV assembly have remained elusive. Here we report that production of HCV trans-complemented particles (HCVTCP) from nonliver cells depends on ectopic expression of apolipoprotein E (ApoE). For efficient virus production by full-length HCV genomes, microRNA 122 (miR-122)-mediated enhancement of RNA replication is additionally required. Typical properties of cell culture-grown HCV (HCVcc) particles from ApoE-expressing nonliver cells are comparable to those of virions derived from human hepatoma cells, although specific infectivity of virions is modestly reduced. Thus, apolipoprotein B (ApoB), microsomal triglyceride transfer protein (MTTP), and apolipoprotein C1 (ApoC1), previously implicated in HCV assembly, are dispensable for production of infectious HCV. In the absence of ApoE, release of core protein from infected cells is reduced, and production of extracellular as well as intracellular infectivity is ablated. Since envelopment of capsids was not impaired, we conclude that ApoE acts after capsid envelopment but prior to secretion of infectious HCV. Remarkably, the lack of ApoE also abrogated direct HCV cell-to-cell transmission. These findings highlight ApoE as a host factor codetermining HCV tissue tropism due to its involvement in a late assembly step and viral cell-to-cell transmission.
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33
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Helle F, Brochot E, Fournier C, Descamps V, Izquierdo L, Hoffmann TW, Morel V, Herpe YE, Bengrine A, Belouzard S, Wychowski C, Dubuisson J, Francois C, Regimbeau JM, Castelain S, Duverlie G. Permissivity of primary human hepatocytes and different hepatoma cell lines to cell culture adapted hepatitis C virus. PLoS One 2013; 8:e70809. [PMID: 23940646 PMCID: PMC3734273 DOI: 10.1371/journal.pone.0070809] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 06/24/2013] [Indexed: 01/16/2023] Open
Abstract
Significant progress has been made in Hepatitis C virus (HCV) culture since the JFH1 strain cloning. However, developing efficient and physiologically relevant culture systems for all viral genotypes remains an important goal. In this work, we aimed at producing a high titer JFH1 derived virus to test different hepatic cells’ permissivity. To this end, we performed successive infections and obtained a JFH1 derived virus reaching high titers. Six potential adaptive mutations were identified (I599V in E2, R1373Q and M1611T in NS3, S2364P and C2441S in NS5A and R2523K in NS5B) and the effect of these mutations on HCV replication and infectious particle production was investigated. This cell culture adapted virus enabled us to efficiently infect primary human hepatocytes, as demonstrated using the RFP-NLS-IPS reporter protein and intracellular HCV RNA quantification. However, the induction of a strong type III interferon response in these cells was responsible for HCV inhibition. The disruption of this innate immune response led to a strong infection enhancement and permitted the detection of viral protein expression by western blotting as well as progeny virus production. This cell culture adapted virus also enabled us to easily compare the permissivity of seven hepatoma cell lines. In particular, we demonstrated that HuH-7, HepG2-CD81, PLC/PRF/5 and Hep3B cells were permissive to HCV entry, replication and secretion even if the efficiency was very low in PLC/PRF/5 and Hep3B cells. In contrast, we did not observe any infection of SNU-182, SNU-398 and SNU-449 hepatoma cells. Using iodixanol density gradients, we also demonstrated that the density profiles of HCV particles produced by PLC/PRF/5 and Hep3B cells were different from that of HuH-7 and HepG2-CD81 derived virions. These results will help the development of a physiologically relevant culture system for HCV patient isolates.
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Affiliation(s)
- Francois Helle
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
- * E-mail:
| | - Etienne Brochot
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Carole Fournier
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Véronique Descamps
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Laure Izquierdo
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Thomas W. Hoffmann
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Virginie Morel
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Yves-Edouard Herpe
- Biobanque de Picardie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Abderrahmane Bengrine
- Biobanque de Picardie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Sandrine Belouzard
- Institut Pasteur de Lille, Center of Infection & Immunity of Lille (CIIL), F-59019 Lille, France; Inserm U1019, F-59019 Lille, France; CNRS UMR8204, F-59021 Lille, France; Univ Lille Nord de France, F-59000 Lille, France
| | - Czeslaw Wychowski
- Institut Pasteur de Lille, Center of Infection & Immunity of Lille (CIIL), F-59019 Lille, France; Inserm U1019, F-59019 Lille, France; CNRS UMR8204, F-59021 Lille, France; Univ Lille Nord de France, F-59000 Lille, France
| | - Jean Dubuisson
- Institut Pasteur de Lille, Center of Infection & Immunity of Lille (CIIL), F-59019 Lille, France; Inserm U1019, F-59019 Lille, France; CNRS UMR8204, F-59021 Lille, France; Univ Lille Nord de France, F-59000 Lille, France
| | - Catherine Francois
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Jean-Marc Regimbeau
- Département de Chirurgie Digestive, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Sandrine Castelain
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
| | - Gilles Duverlie
- EA4294, Laboratoire de Virologie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
- Biobanque de Picardie, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, Amiens, France
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Hepatitis C virus, cholesterol and lipoproteins--impact for the viral life cycle and pathogenesis of liver disease. Viruses 2013; 5:1292-324. [PMID: 23698400 PMCID: PMC3712309 DOI: 10.3390/v5051292] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/10/2013] [Accepted: 04/27/2013] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) is a leading cause of chronic liver disease, including chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Hepatitis C infection associates with lipid and lipoprotein metabolism disorders such as hepatic steatosis, hypobetalipoproteinemia, and hypocholesterolemia. Furthermore, virus production is dependent on hepatic very-low-density lipoprotein (VLDL) assembly, and circulating virions are physically associated with lipoproteins in complexes termed lipoviral particles. Evidence has indicated several functional roles for the formation of these complexes, including co-opting of lipoprotein receptors for attachment and entry, concealing epitopes to facilitate immune escape, and hijacking host factors for HCV maturation and secretion. Here, we review the evidence surrounding pathogenesis of the hepatitis C infection regarding lipoprotein engagement, cholesterol and triglyceride regulation, and the molecular mechanisms underlying these effects.
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