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Center RJ, Boo I, Phu L, McGregor J, Poumbourios P, Drummer HE. Enhancing the antigenicity and immunogenicity of monomeric forms of hepatitis C virus E2 for use as a preventive vaccine. J Biol Chem 2020; 295:7179-7192. [PMID: 32299914 PMCID: PMC7247312 DOI: 10.1074/jbc.ra120.013015] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/13/2020] [Indexed: 12/13/2022] Open
Abstract
The E2 glycoprotein of hepatitis C virus (HCV) is the major target of broadly neutralizing antibodies (bNAbs) that are critical for the efficacy of a prophylactic HCV vaccine. We previously showed that a cell culture-derived, disulfide-linked high-molecular-weight (HMW) form of the E2 receptor-binding domain lacking three variable regions, Δ123-HMW, elicits broad neutralizing activity against the seven major genotypes of HCV. A limitation to the use of this antigen is that it is produced only at low yields and does not have a homogeneous composition. Here, we employed a sequential reduction and oxidation strategy to efficiently refold two high-yielding monomeric E2 species, D123 and a disulfide-minimized version (D123A7), into disulfide-linked HMW-like species (Δ123r and Δ123A7r). These proteins exhibited normal reactivity to bNAbs with continuous epitopes on the neutralizing face of E2, but reduced reactivity to conformation-dependent bNAbs and nonneutralizing antibodies (non-NAbs) compared with the corresponding monomeric species. Δ123r and Δ123A7r recapitulated the immunogenic properties of cell culture-derived D123-HMW in guinea pigs. The refolded antigens elicited antibodies that neutralized homologous and heterologous HCV genotypes, blocked the interaction between E2 and its cellular receptor CD81, and targeted the AS412, AS434, and AR3 domains. Of note, antibodies directed to epitopes overlapping with those of non-NAbs were absent. The approach to E2 antigen engineering outlined here provides an avenue for the development of preventive HCV vaccine candidates that induce bNAbs at higher yield and lower cost.
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Affiliation(s)
- Rob J Center
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia; Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3000, Australia
| | - Irene Boo
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia
| | - Lilian Phu
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia; Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3000, Australia
| | - Joey McGregor
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia; Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3000, Australia
| | - Pantelis Poumbourios
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia; Department of Microbiology, Monash University, Clayton 3056, Australia
| | - Heidi E Drummer
- Burnet Institute, 85 Commercial Road, Melbourne 3004, Australia; Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne 3000, Australia; Department of Microbiology, Monash University, Clayton 3056, Australia.
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Prentoe J, Bukh J. Hypervariable Region 1 in Envelope Protein 2 of Hepatitis C Virus: A Linchpin in Neutralizing Antibody Evasion and Viral Entry. Front Immunol 2018; 9:2146. [PMID: 30319614 PMCID: PMC6170631 DOI: 10.3389/fimmu.2018.02146] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 08/30/2018] [Indexed: 12/15/2022] Open
Abstract
Chronic hepatitis C virus (HCV) infection is the cause of about 400,000 annual liver disease-related deaths. The global spread of this important human pathogen can potentially be prevented through the development of a vaccine, but this challenge has proven difficult, and much remains unknown about the multitude of mechanisms by which this heterogeneous RNA virus evades inactivation by neutralizing antibodies (NAbs). The N-terminal motif of envelope protein 2 (E2), termed hypervariable region 1 (HVR1), changes rapidly in immunoglobulin-competent patients due to antibody-driven antigenic drift. HVR1 contains NAb epitopes and is directly involved in protecting diverse antibody-specific epitopes on E1, E2, and E1/E2 through incompletely understood mechanisms. The ability of HVR1 to protect HCV from NAbs appears linked with modulation of HCV entry co-receptor interactions. Thus, removal of HVR1 increases interaction with CD81, while altering interaction with scavenger receptor class B, type I (SR-BI) in a complex fashion, and decreasing interaction with low-density lipoprotein receptor. Despite intensive efforts this modulation of receptor interactions by HVR1 remains incompletely understood. SR-BI has received the most attention and it appears that HVR1 is involved in a multimodal HCV/SR-BI interaction involving high-density-lipoprotein associated ApoCI, which may prime the virus for later entry events by exposing conserved NAb epitopes, like those in the CD81 binding site. To fully elucidate the multifunctional role of HVR1 in HCV entry and NAb evasion, improved E1/E2 models and comparative studies with other NAb evasion strategies are needed. Derived knowledge may be instrumental in the development of a prophylactic HCV vaccine.
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Affiliation(s)
- Jannick Prentoe
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, Copenhagen, Denmark.,Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, Copenhagen, Denmark.,Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Identification and characterization of a natural inter-genotypic (2b/1b) recombinant hepatitis C virus in Japan. Arch Virol 2011; 156:1591-601. [DOI: 10.1007/s00705-011-1038-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 05/17/2011] [Indexed: 12/15/2022]
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Smith J, Aberle JH, Fleming VM, Ferenci P, Thomson EC, Karayiannis P, McLean AR, Holzmann H, Klenerman P. Dynamic coinfection with multiple viral subtypes in acute hepatitis C. J Infect Dis 2010; 202:1770-9. [PMID: 21067369 PMCID: PMC3107554 DOI: 10.1086/657317] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Accepted: 07/19/2010] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION Acute hepatitis C virus (HCV) infection is rarely studied, but virus sequence evolution and host-virus dynamics during this early stage may influence the outcome of infection. Hypervariable region 1 (HVR1) is genetically diverse and under selective pressure from the host immune response. We analyzed HVR1 evolution by frequent sampling of an acutely infected HCV cohort. METHODS Three or more pretreatment samples were obtained from each of 10 acutely infected subjects. Polymerase chain reaction amplification was performed with multiple primer combinations to identify the full range of sequences present. Positive samples were cloned and sequenced. Phylogenetic analyses were used to assess viral diversity. RESULTS Eight of the 10 subjects were coinfected with at least 2 HCV subtypes. Multiple subtypes were detected in individual samples, and their relative proportions changed through acute infection. The subjects with the most complex subtype structure also had a dynamic viral load; however, changes in viral load were not directly linked to changes in subtype. CONCLUSIONS This well-sampled cohort with acute HCV infection was characterized by dynamic coinfection with multiple viral subtypes, representing a highly complex virologic landscape extremely early in infection.
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Affiliation(s)
- Jennifer Smith
- Institute for Emerging Infections, University of Oxford, Oxford
| | - Judith H. Aberle
- Institute of Virology, Medical University of Vienna, Vienna, Austria
| | - Vicki M. Fleming
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford
| | - Peter Ferenci
- Department of Internal Medicine, Gastroenterology, and Hepatology, Medical University of Vienna, Vienna, Austria
| | - Emma C. Thomson
- Department of Hepatology, Imperial College, London, United Kingdom
| | | | | | | | - Paul Klenerman
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford
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Al-Qahtani AA, Kessie G, Cruz DD, Al-Faleh FZ, Al-Ahdal MN. Quasispecies of genotype 4 of hepatitis C virus genomes in Saudi patients managed with interferon alfa and ribavirin therapy. Ann Saudi Med 2010; 30:109-14. [PMID: 20220259 PMCID: PMC2855060 DOI: 10.4103/0256-4947.60515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Many patients with hepatitis C virus (HCV) infection do not respond to antiviral treatment, possibly due to viral quasispecies. We aimed to investigate whether the quasispecies population could be used as a predictor of response to therapy in our patients. METHODS The quasispecies of HCV genotype 4 (HCV-4) were studied in 25 naïve Saudi patients at zero, three, and six months following interferon alfa and ribavirin combination therapy. Hypervariable region 1 within the E2/NS1 gene of the virus was analyzed by the single-strand conformation polymorphism (SSCP) technique after amplification. RESULTS Pretreatment DNA bands by SSCP (2-7 bands) were detected in all patients. In those who achieved a complete virological response within six months (viral load P=.53). Two of the four patients with pretreatment high viral load and the same or decreased composition of quasispecies bands responded to the therapy. CONCLUSION Quasispecies in our studied patients cannot be used to predict responsiveness to treatment, but may offer an explanation for failure of most HCV-4 patients to respond to interferon alfa and ribavirin therapy.
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Affiliation(s)
- Ahmed A. Al-Qahtani
- From the Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - George Kessie
- From the Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- Current address: SAIC-Frederick, National Cancer Institute at Frederick, P.O. Box B Frederick, Maryland, 21702 USA
| | - Damian Dela Cruz
- From the Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Faleh Z. Al-Faleh
- From the Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mohammed N. Al-Ahdal
- From the Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- From the Department of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
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Yu KL, You JC. Differential Expression of HCV Core Protein from Two Different Quasispecies. Biomol Ther (Seoul) 2009. [DOI: 10.4062/biomolther.2009.17.2.151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Li C, Allain JP. Chimeric monoclonal antibodies to hypervariable region 1 of hepatitis C virus. J Gen Virol 2005; 86:1709-1716. [PMID: 15914849 DOI: 10.1099/vir.0.80912-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Two chimeric monoclonal antibodies (cAbs), 2P24 and 15H4, to hypervariable region 1 (HVR1) of hepatitis C virus (HCV) were constructed by grafting the variable regions of murine monoclonal antibodies (mAbs) 2P24 and 15H4 to a human IgG1 kappa constant region. Two cAb-producing cell lines were adapted to serum-free media. Both cAb 2P24 and cAb 15H4 cell lines produced 3-5 microg antibodies ml(-1) after 3-5 days culture. cAbs retained binding characteristics similar to those observed in the original mAbs. There was no clear difference in affinity between binding of cAbs and mAbs to seven HVR1 peptides. Mixtures of biotinylated cAbs or mAbs reacted with 32 (86 %) and 31 (84 %) of 37 HVR1 peptides, respectively, but not with non-HVR1 control peptides. HCV from 16 out of 18 (89 %) random HCV-containing plasmas was captured by the mixture of biotinylated cAbs. The capture from IgG-depleted plasmas suggested that cAbs captured mainly free rather than complexed HCV, irrespective of genotype. A mixture of the two cAbs inhibited HCV binding to Molt-4 cells in a dose-dependent manner. These cAbs may be useful for prevention of nosocomial HCV infection and passive immunization to prevent HCV reinfection after liver transplantation.
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Affiliation(s)
- Chengyao Li
- National Blood Service, Division of Transfusion Medicine, East Anglia Blood Centre, Long Road, Cambridge CB2 2PT, UK
| | - Jean-Pierre Allain
- Department of Haematology, Division of Transfusion Medicine, East Anglia Blood Centre, Long Road, Cambridge CB2 2PT, UK
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Gao G, Stuver SO, Okayama A, Tsubouchi H, Mueller NE, Tabor E. The minimum number of clones necessary to sequence in order to obtain the maximum information about hepatitis C virus quasispecies: a comparison of subjects with and without liver cancer. J Viral Hepat 2005; 12:46-50. [PMID: 15655047 DOI: 10.1111/j.1365-2893.2005.00546.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Most studies of hepatitis C virus (HCV) quasispecies have reported the results of sequencing only three to five clones per sample. The possibility that sequencing so few clones might not provide a representative picture of the quasispecies present in a sample has never been evaluated. The present study was conducted to evaluate whether sequencing greater numbers of clones results in better information about the HCV quasispecies number and distribution, and to compare the HCV quasispecies in liver cancer cases and controls. RNA was extracted from serial serum samples from six subjects with HCV-associated liver cancer and 11 age- and sex-matched HCV-infected controls without liver cancer. The hypervariable region 1 (HVR1) of the HCV genome was amplified, cloned, and sequenced. For further studies of 12 serum samples from two liver cancer cases and two matched controls, successive groups of 10 additional clones were sequenced up to a total of 50 clones per serum sample. When only 10 clones were sequenced from each specimen, no consistent differences were seen between the number of HCV quasispecies in the six liver cancer cases and the 11 controls. However, sequencing 40 clones from each of 12 samples from two liver cancer cases and two controls revealed a greater number of quasispecies in liver cancer cases than in controls. Testing an additional 10 clones (50 clones per sample) did not significantly increase the number of quasispecies detected.
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Affiliation(s)
- G Gao
- Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration, Bethesda, MD, USA
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Xiu BS, Ling SG, Song XG, Zhang HQ, Chen K, Zhu CX. Cross-reactivity of hypervariable region 1 chimera of hepatitis C virus. World J Gastroenterol 2003; 9:1256-60. [PMID: 12800235 PMCID: PMC4611795 DOI: 10.3748/wjg.v9.i6.1256] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2003] [Revised: 02/04/2003] [Accepted: 02/16/2003] [Indexed: 02/06/2023] Open
Abstract
AIM To analyze the amino acid sequences of hypervariable region 1 (HVR1) of HCV isolates in China and to construct a combinatorial chimeric HVR1 protein having a very broad high cross-reactivity. METHODS All of the published HVR1 sequences from China were collected and processed with a computer program. Several representative HVR1's sequences were formulated based on a consensus profile and homology within certain subdivision. A few reported HVR1 mimotope sequences were also included for a broader representation. All of them were cloned and expressed in E.coli. The cross-reactivity of the purified recombinant HVR1 antigens was tested by ELISA with a panel of sera from HCV infected patients in China. Some of them were further ligated together to form a combinatorial HVR1 chimera. RESULTS Altogether 12 HVR1(s) were selected and expressed in E.coli and purified to homogeneity. All of these purified antigens showed some cross-reactivity with sera in a 27 HCV positive panel. Recombinant HVR1s of No. 1, 2, 4, and 8# showing broad cross-reactivities and complementarity with each other, were selected for the ligation elements. The chimera containing these 4 HVR1s was highly expressed in E.coli. The purified chimeric antigen could react not only with all the HCV antibody positive sera in the panel but also with 90/91 sera of HCV -infected patients. CONCLUSION The chimeric antigen was shown to have a broad cross-reactivity. It may be helpful for solving the problem caused by high variability of HCV, and in the efforts for a novel vaccine against the virus.
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Affiliation(s)
- Bing-Shui Xiu
- Laboratory of Molecular Virology, Institute of Basic Medical Sciences, Academy of Military Medical Sciences, Beijing 100850, P.R.China
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Zou S, Forrester L, Giulivi A. Hepatitis C update. Canadian Journal of Public Health 2003. [PMID: 12675169 DOI: 10.1007/bf03404585] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Shimian Zou
- Health Care Acquired Infections Division, Centre for Infectious Disease Prevention and Control, Population and Public Health Branch, Health Canada, Ottawa, ON.
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Scarselli E, Ansuini H, Cerino R, Roccasecca RM, Acali S, Filocamo G, Traboni C, Nicosia A, Cortese R, Vitelli A. The human scavenger receptor class B type I is a novel candidate receptor for the hepatitis C virus. EMBO J 2002; 21:5017-25. [PMID: 12356718 PMCID: PMC129051 DOI: 10.1093/emboj/cdf529] [Citation(s) in RCA: 868] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We discovered that the hepatitis C virus (HCV) envelope glycoprotein E2 binds to human hepatoma cell lines independently of the previously proposed HCV receptor CD81. Comparative binding studies using recombinant E2 from the most prevalent 1a and 1b genotypes revealed that E2 recognition by hepatoma cells is independent from the viral isolate, while E2-CD81 interaction is isolate specific. Binding of soluble E2 to human hepatoma cells was impaired by deletion of the hypervariable region 1 (HVR1), but the wild-type phenotype was recovered by introducing a compensatory mutation reported previously to rescue infectivity of an HVR1-deleted HCV infectious clone. We have identified the receptor responsible for E2 binding to human hepatic cells as the human scavenger receptor class B type I (SR-BI). E2-SR-BI interaction is very selective since neither mouse SR-BI nor the closely related human scavenger receptor CD36, were able to bind E2. Finally, E2 recognition by SR-BI was competed out in an isolate-specific manner both on the hepatoma cell line and on the human SR-BI-transfected cell line by an anti-HVR1 monoclonal antibody.
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MESH Headings
- Animals
- Antigens, CD/physiology
- CD36 Antigens/physiology
- CHO Cells
- Carcinoma, Hepatocellular
- Cloning, Molecular
- Cricetinae
- Flow Cytometry
- Hepacivirus/physiology
- Humans
- Leukemia, T-Cell
- Liver Neoplasms
- Membrane Proteins/physiology
- Receptors, Immunologic
- Receptors, Lipoprotein/physiology
- Receptors, Scavenger
- Receptors, Virus/physiology
- Recombinant Proteins/metabolism
- Scavenger Receptors, Class B
- Tetraspanin 28
- Tumor Cells, Cultured
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Affiliation(s)
- Elisa Scarselli
- Istituto di Ricerche di Biologia Molecolare P.Angeletti (IRBM), Via Pontina Km 30.600, 00040 Pomezia (Roma), Italy
Present address: Department of Biochemistry, 414 Wartik Laboratory, Pennsylvania State University, University Park, PA 16802, USA Corresponding author e-mail:
| | | | | | - Rosa Maria Roccasecca
- Istituto di Ricerche di Biologia Molecolare P.Angeletti (IRBM), Via Pontina Km 30.600, 00040 Pomezia (Roma), Italy
Present address: Department of Biochemistry, 414 Wartik Laboratory, Pennsylvania State University, University Park, PA 16802, USA Corresponding author e-mail:
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Hino K, Korenaga M, Orito E, Katoh Y, Yamaguchi Y, Ren F, Kitase A, Satoh Y, Fujiwara D, Okita K. Constrained genomic and conformational variability of the hypervariable region 1 of hepatitis C virus in chronically infected patients. J Viral Hepat 2002; 9:194-201. [PMID: 12010507 DOI: 10.1046/j.1365-2893.2002.00349.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
We analysed the genomic and conformational variability of the hypervariable region 1 (HVR1) of the hepatitis C virus (HCV) to evaluate the importance of its biological role. A total of 865 genotype 1b HVR1 subclones were collected from serially sampled sera in 11 patients with chronic hepatitis C, four of whom received interferon therapy. Consequently, 169 distinct sequences were examined for amino acid substitutions as well as hydrophilic or hydrophobic profile at each amino acid position within HVR1. Secondary structure of HVR1 was also predicted by the method of Robson in 90 distinct sequences from eight patients, including three interferon-treated patients. Some positions within the HVR1 were invariable or nearly so as to amino acid substitution. Hydrophilic or hydrophobic residues exclusively predominated at several positions. These constrained amino acid replacement and hydrophilic or hydrophobic profiles were conserved irrespective of interferon therapy, though the frequency of amino acid replacement was greater at almost all amino acid positions within the HVR1 in interferon-treated patients. The quasispecies of HCV showed various secondary structures of HVR1, but many sequences seemed to have common characteristics. beta sheet conformations around both the N-terminus and position 20 (numbered from the NH2 terminus of E2 envelope glycoprotein), and/or coil structures around the C-terminus of HVR1 could be identified. These results suggest that HVR1 amino acid replacements are strongly constrained by a well-ordered structure, in spite of being tolerant to amino acid substitutions, and imply an important biological role of the HVR1 protein in HCV replication.
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Affiliation(s)
- Keisuke Hino
- Department of Gastroenterology and Hepatology, Yamaguchi University School of Medicine, Yamaguchi, Japan.
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