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Jamali E, Quadeer AA, Tedla N, McKay MR, Lloyd A, Walker MR, Bull RA. Anti-HCV antibodies: A battle for breadth and potency. Antiviral Res 2025; 238:106165. [PMID: 40239843 DOI: 10.1016/j.antiviral.2025.106165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2025] [Revised: 04/08/2025] [Accepted: 04/12/2025] [Indexed: 04/18/2025]
Affiliation(s)
- Elham Jamali
- Viral Immunology Systems Program, The Kirby Institute, Medicine & Health, University of New South Wales, Sydney, 2052, Australia; School of Biomedical Sciences, Medicine & Health, University of New South Wales, Sydney, 2052, Australia
| | - Ahmed Abdul Quadeer
- Department of Electrical and Electronic Engineering, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Nicodemus Tedla
- School of Biomedical Sciences, Medicine & Health, University of New South Wales, Sydney, 2052, Australia
| | - Matthew R McKay
- Department of Electrical and Electronic Engineering, University of Melbourne, Parkville, VIC, 3010, Australia; Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, 3000, Australia
| | - Andrew Lloyd
- Viral Immunology Systems Program, The Kirby Institute, Medicine & Health, University of New South Wales, Sydney, 2052, Australia
| | - Melanie R Walker
- Viral Immunology Systems Program, The Kirby Institute, Medicine & Health, University of New South Wales, Sydney, 2052, Australia; School of Biomedical Sciences, Medicine & Health, University of New South Wales, Sydney, 2052, Australia
| | - Rowena A Bull
- Viral Immunology Systems Program, The Kirby Institute, Medicine & Health, University of New South Wales, Sydney, 2052, Australia; School of Biomedical Sciences, Medicine & Health, University of New South Wales, Sydney, 2052, Australia.
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2
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Underwood AP, Gupta M, Wu BR, Eltahla AA, Boo I, Wang JJ, Agapiou D, Abayasingam A, Reynaldi A, Keoshkerian E, Zhao Y, Brasher N, Walker MR, Bukh J, Maher L, Gordon T, Davenport MP, Luciani F, Drummer HE, Lloyd AR, Bull RA. B-cell characteristics define HCV reinfection outcome. J Hepatol 2024; 81:415-428. [PMID: 38604387 DOI: 10.1016/j.jhep.2024.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 03/20/2024] [Accepted: 04/03/2024] [Indexed: 04/13/2024]
Abstract
BACKGROUND & AIMS In individuals highly exposed to HCV, reinfection is common, suggesting that natural development of sterilising immunity is difficult. In those that are reinfected, some will develop a persistent infection, while a small proportion repeatedly clear the virus, suggesting natural protection is possible. The aim of this study was to characterise immune responses associated with rapid natural clearance of HCV reinfection. METHODS Broad neutralising antibodies (nAbs) and Envelope 2 (E2)-specific memory B cell (MBC) responses were examined longitudinally in 15 individuals with varied reinfection outcomes. RESULTS Broad nAb responses were associated with MBC recall, but not with clearance of reinfection. Strong evidence of antigen imprinting was found, and the B-cell receptor repertoire showed a high level of clonality with ongoing somatic hypermutation of many clones over subsequent reinfection events. Single-cell transcriptomic analyses showed that cleared reinfections featured an activated transcriptomic profile in HCV-specific B cells that rapidly expanded upon reinfection. CONCLUSIONS MBC quality, but not necessarily breadth of nAb responses, is important for protection against antigenically diverse variants, which is encouraging for HCV vaccine development. IMPACT AND IMPLICATIONS HCV continues to have a major health burden globally. Limitations in the health infrastructure for diagnosis and treatment, as well as high rates of reinfection, indicate that a vaccine that can protect against chronic HCV infection will greatly complement current efforts to eliminate HCV-related disease. With alternative approaches to testing vaccines, such as controlled human inoculation trials under consideration, we desperately need to identify the correlates of immune protection. In this study, in a small but rare cohort of high-risk injecting drug users who were reinfected multiple times, breadth of neutralisation was not associated with ultimate clearance of the reinfection event. Alternatively, characteristics of the HCV-specific B-cell response associated with B-cell proliferation were. This study indicates that humoral responses are important for protection and suggests that for genetically very diverse viruses, such as HCV, it may be beneficial to look beyond just antibodies as correlates of protection.
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Affiliation(s)
- Alexander P Underwood
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre and Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Money Gupta
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Bing-Ru Wu
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Auda A Eltahla
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Irene Boo
- Burnet Institute, Melbourne, VIC, Australia
| | - Jing Jing Wang
- Department of Immunology Flinders Medical Centre and Flinders University, SA Pathology Bedford Park, SA, Australia
| | - David Agapiou
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Arunasingam Abayasingam
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Arnold Reynaldi
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | | | - Yanran Zhao
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Nicholas Brasher
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Melanie R Walker
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre and Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lisa Maher
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Tom Gordon
- Department of Immunology Flinders Medical Centre and Flinders University, SA Pathology Bedford Park, SA, Australia
| | - Miles P Davenport
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Fabio Luciani
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Heidi E Drummer
- Burnet Institute, Melbourne, VIC, Australia; Department of Microbiology, Monash University, Clayton, VIC, Australia; Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Andrew R Lloyd
- The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia
| | - Rowena A Bull
- School of Biomedical Science, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia; The Kirby Institute, Faculty of Medicine and Health, UNSW, Sydney, NSW, Australia.
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3
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Garbuglia AR, Pauciullo S, Zulian V, Del Porto P. Update on Hepatitis C Vaccine: Results and Challenges. Viruses 2024; 16:1337. [PMID: 39205311 PMCID: PMC11359353 DOI: 10.3390/v16081337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/15/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024] Open
Abstract
Therapy against the Hepatitis C virus (HCV) has significantly improved with the introduction of direct-acting antiviral drugs (DAAs), achieving over 95% sustained virological response (SVR). Despite this, the development of an effective anti-HCV vaccine remains a critical challenge due to the low number of patients treated with DAAs and the occurrence of HCV reinfections in high-risk groups. Current vaccine strategies aim to stimulate either B-cell or T-cell responses. Vaccines based on E1 and E2 proteins can elicit broad cross-neutralizing antibodies against all major HCV genotypes, though with varying efficiencies and without full protection against infection. In humans, the neutralizing antibodies induced by such vaccines mainly target the AR3 region, but their levels are generally insufficient for broad neutralization. Various HCV proteins expressed through different viral vectors have been utilized to elicit T cell immune responses, showing sustained expansion of HCV-specific effector memory T cells and improved proliferation and polyfunctionality of memory T cells over time. However, despite these advancements, the frequency and effectiveness of T-cell responses remain limited.
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Affiliation(s)
- Anna Rosa Garbuglia
- Laboratory of Virology, National Institute for Infectious Diseases “Lazzaro Spallanzani” (IRCCS), 00149 Rome, Italy; (S.P.); (V.Z.)
| | - Silvia Pauciullo
- Laboratory of Virology, National Institute for Infectious Diseases “Lazzaro Spallanzani” (IRCCS), 00149 Rome, Italy; (S.P.); (V.Z.)
| | - Verdiana Zulian
- Laboratory of Virology, National Institute for Infectious Diseases “Lazzaro Spallanzani” (IRCCS), 00149 Rome, Italy; (S.P.); (V.Z.)
| | - Paola Del Porto
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University of Rome, 00100 Rome, Italy;
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4
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Costa GL, Sautto GA. Exploring T-Cell Immunity to Hepatitis C Virus: Insights from Different Vaccine and Antigen Presentation Strategies. Vaccines (Basel) 2024; 12:890. [PMID: 39204016 PMCID: PMC11359689 DOI: 10.3390/vaccines12080890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 07/25/2024] [Accepted: 08/02/2024] [Indexed: 09/03/2024] Open
Abstract
The hepatitis C virus (HCV) is responsible for approximately 50 million infections worldwide. Effective drug treatments while available face access barriers, and vaccine development is hampered by viral hypervariability and immune evasion mechanisms. The CD4+ and CD8+ T-cell responses targeting HCV non-structural (NS) proteins have shown a role in the viral clearance. In this paper, we reviewed the studies exploring the relationship between HCV structural and NS proteins and their effects in contributing to the elicitation of an effective T-cell immune response. The use of different vaccine platforms, such as viral vectors and virus-like particles, underscores their versability and efficacy for vaccine development. Diverse HCV antigens demonstrated immunogenicity, eliciting a robust immune response, positioning them as promising vaccine candidates for protein/peptide-, DNA-, or RNA-based vaccines. Moreover, adjuvant selection plays a pivotal role in modulating the immune response. This review emphasizes the importance of HCV proteins and vaccination strategies in vaccine development. In particular, the NS proteins are the main focus, given their pivotal role in T-cell-mediated immunity and their sequence conservation, making them valuable vaccine targets.
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Affiliation(s)
| | - Giuseppe A. Sautto
- Florida Research and Innovation Center, Cleveland Clinic, Port Saint Lucie, FL 34987, USA;
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5
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Hu W, Zhao J, Hu Y, Song S, Chen X, Sun Y. Huangqi Jiuni decoction prevents acute kidney injury induced by severe burns by inhibiting activation of the TNF/NF-κB pathway. JOURNAL OF ETHNOPHARMACOLOGY 2024; 320:117344. [PMID: 37949330 DOI: 10.1016/j.jep.2023.117344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/15/2023] [Accepted: 10/22/2023] [Indexed: 11/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Huangqi Jiuni decoction (HQJND) is a prescription for the treatment of severe burns provided based on traditional Chinese and Western medicine, which is created by the First Affiliated Hospital of Anhui Medical University. It consists of 12 herbs and has been used clinically for decades. It has greatly shortened the course of the disease, but the mechanism by which HQJND treats the disease still remains unclear. AIM OF THE STUDY Hence, the objective of this investigation was to utilize modern pharmacological tools to demonstrate the efficacy and mechanism of HQJND in the treatment of acute kidney injury (AKI) caused by severe burns. MATERIALS AND METHODS In this study, the chemical constituents in HQJND were first examined using liquid chromatography tandem mass spectrometry (LC-MS/MS). Then, by using network pharmacology, we screened the targets of drug and disease action, and predicted the signaling pathways acting in the course of drug treatment of disease. Finally, we attempted to verify the efficacy of the drug and explored its therapeutic mechanism after the establishment of an animal model, herbal gavage treatment, collection of rat kidneys and serum for renal function, quantitative real-time Polymerase Chain Reaction (RT-qPCR), Western Blotting (WB), Hematoxylin and eosin (HE) staining and Immunohistochemistry (IHC). RESULTS The 14 important active ingredients in HQJND was analyzed by liquid chromatography tandem mass spectrometry, while network pharmacology screening was performed to identify 353 disease-associated marker genes and 286 drug targets, finally identifying the TNF/NF-κB (tumor necrosis factor/nuclear factor kappa-B) signaling site: the key pathway of burn-induced acute kidney injury when HQJND intervened. The serum renal function and histopathology of rats demonstrated that the use of HQJND significantly improved the renal function in severe burns. RT-qPCR and WB confirmed that the TNF/NF-κB signaling pathway was activated in the Model group of rats, and HQJND could curb the signaling pathway because it moderated the expressions of key proteins in the process. CONCLUSION Based on modern pharmacology, we explored an effective herbal preparation to ameliorate the impairment of renal function after severe burns, which is most likely to function through the TNF/NF-κB signaling pathway.
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Affiliation(s)
- Wanxuan Hu
- Department of Burn, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, PR China
| | - Jie Zhao
- Department of Chinese Medicine, The First Affiliated Hospital of Anhui Medical University, No.218, Jixi Road, Shushan District, Hefei, Anhui, 230032, PR China; Department of Chinese Integrative Medicine, Anhui Medical University, No. 80, Meishan Road, Shushan District, Hefei, Anhui, 230032, PR China
| | - Yuxin Hu
- Department of Chinese Integrative Medicine, Anhui Medical University, No. 80, Meishan Road, Shushan District, Hefei, Anhui, 230032, PR China
| | - Shuai Song
- Department of Pharmacy, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, PR China
| | - Xulin Chen
- Department of Burn, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, PR China
| | - Yexiang Sun
- Department of Burn, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, PR China.
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6
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Frumento N, Sinnis-Bourozikas A, Paul HT, Stavrakis G, Zahid MN, Wang S, Ray SC, Flyak AI, Shaw GM, Cox AL, Bailey JR. Neutralizing antibodies evolve to exploit vulnerable sites in the HCV envelope glycoprotein E2 and mediate spontaneous clearance of infection. Immunity 2024; 57:40-51.e5. [PMID: 38171362 PMCID: PMC10874496 DOI: 10.1016/j.immuni.2023.12.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/28/2023] [Accepted: 12/06/2023] [Indexed: 01/05/2024]
Abstract
Individuals who clear primary hepatitis C virus (HCV) infections clear subsequent reinfections more than 80% of the time, but the mechanisms are poorly defined. Here, we used HCV variants and plasma from individuals with repeated clearance to characterize longitudinal changes in envelope glycoprotein E2 sequences, function, and neutralizing antibody (NAb) resistance. Clearance of infection was associated with early selection of viruses with NAb resistance substitutions that also reduced E2 binding to CD81, the primary HCV receptor. Later, peri-clearance plasma samples regained neutralizing capacity against these variants. We identified a subset of broadly NAbs (bNAbs) for which these loss-of-fitness substitutions conferred resistance to unmutated bNAb ancestors but increased sensitivity to mature bNAbs. These data demonstrate a mechanism by which neutralizing antibodies contribute to repeated immune-mediated HCV clearance, identifying specific bNAbs that exploit fundamental vulnerabilities in E2. The induction of bNAbs with these specificities should be a goal of HCV vaccine development.
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Affiliation(s)
- Nicole Frumento
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ariadne Sinnis-Bourozikas
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harry T Paul
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Georgia Stavrakis
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Muhammad N Zahid
- University of Bahrain, Department of Biology, College of Science, Sakhir Campus, Sakhir, Bahrain
| | - Shuyi Wang
- Department of Medicine and Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Stuart C Ray
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Andrew I Flyak
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA
| | - George M Shaw
- Department of Medicine and Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrea L Cox
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Justin R Bailey
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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7
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Adhikari A, Abayasingam A, Brasher NA, Kim HN, Lord M, Agapiou D, Maher L, Rodrigo C, Lloyd AR, Bull RA, Tedla N. Characterization of antibody-dependent cellular phagocytosis in patients infected with hepatitis C virus with different clinical outcomes. J Med Virol 2024; 96:e29381. [PMID: 38235622 PMCID: PMC10953302 DOI: 10.1002/jmv.29381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 12/10/2023] [Accepted: 12/28/2023] [Indexed: 01/19/2024]
Abstract
Early neutralizing antibodies against hepatitis C virus (HCV) and CD8 + T cell effector responses can lead to viral clearance. However, these functions alone are not sufficient to protect patients against HCV infection, thus undefined additional antiviral immune mechanisms are required. In recent years, Fc-receptor-dependent antibody effector functions, particularly, antibody-dependent cellular phagocytosis (ADCP) were shown to offer immune protection against several RNA viruses. However, its development and clinical role in patients with HCV infection remain unknown. In this study, we found that patients with chronic GT1a or GT3a HCV infection had significantly higher concentrations of anti-envelope 2 (E2) antibodies, predominantly IgG1 subclass, than patients that cleared the viruses while the latter had antibodies with higher affinities. 97% of the patients with HCV had measurable ADCP of whom patients with chronic disease showed significantly higher ADCP than those who naturally cleared the virus. Epitope mapping studies showed that patients with antibodies that target antigenic domains on the HCV E2 protein that are known to associate with neutralization function are also strongly associated with ADCP, suggesting antibodies with overlapping/dual functions. Correlation studies showed that ADCP significantly correlated with plasma anti-E2 antibody levels and neutralization function regardless of clinical outcome and genotype of infecting virus, while a significant correlation between ADCP and affinity was only evident in patients that cleared the virus. These results suggest ADCP was mostly driven by antibody titer in patients with chronic disease while maintained in clearers due to the quality (affinity) of their anti-E2 antibodies despite having lower antibody titers.
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Affiliation(s)
- Anurag Adhikari
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
- Department of Infection and ImmunologyKathmandu Research Institute for Biological SciencesLalitpurNepal
| | - Arunasingam Abayasingam
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
| | - Nicholas A. Brasher
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
| | - Ha Na Kim
- Molecular Surface Interaction Laboratory, Mark Wainwright Analytical CentreUNSW SydneySydneyNew South WalesAustralia
| | - Megan Lord
- Molecular Surface Interaction Laboratory, Mark Wainwright Analytical CentreUNSW SydneySydneyNew South WalesAustralia
- Graduate School of Biomedical Engineering, Faculty of EngineeringUNSW SydneySydneyNew South WalesAustralia
| | - David Agapiou
- The Kirby InstituteUNSW AustraliaSydneyNew South WalesAustralia
| | - Lisa Maher
- The Kirby InstituteUNSW AustraliaSydneyNew South WalesAustralia
| | - Chaturaka Rodrigo
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
| | - Andrew R. Lloyd
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
- The Kirby InstituteUNSW AustraliaSydneyNew South WalesAustralia
| | - Rowena A. Bull
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
- The Kirby InstituteUNSW AustraliaSydneyNew South WalesAustralia
| | - Nicodemus Tedla
- School of Biomedical Sciences, Faculty of MedicineUNSW AustraliaSydneyNew South WalesAustralia
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8
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Identification of human progenitors of exhausted CD8 + T cells associated with elevated IFN-γ response in early phase of viral infection. Nat Commun 2022; 13:7543. [PMID: 36477661 PMCID: PMC9729230 DOI: 10.1038/s41467-022-35281-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 11/25/2022] [Indexed: 12/12/2022] Open
Abstract
T cell exhaustion is a hallmark of hepatitis C virus (HCV) infection and limits protective immunity in chronic viral infections and cancer. Limited knowledge exists of the initial viral and immune dynamics that characterise exhaustion in humans. We studied longitudinal blood samples from a unique cohort of individuals with primary infection using single-cell multi-omics to identify the functions and phenotypes of HCV-specific CD8+ T cells. Early elevated IFN-γ response against the transmitted virus is associated with the rate of immune escape, larger clonal expansion, and early onset of exhaustion. Irrespective of disease outcome, we find heterogeneous subsets of progenitors of exhaustion, based on the level of PD-1 expression and loss of AP-1 transcription factors. Intra-clonal analysis shows distinct trajectories with multiple fates and evolutionary plasticity of precursor cells. These findings challenge the current paradigm on the contribution of CD8+ T cells to HCV disease outcome and provide data for future studies on T cell differentiation in human infections.
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9
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Aziz H, Fatima S, Mahmood H, Muhammad S, Saeed MA, Khurshid S, Aslam W, Aziz S, Faheem M. Antibody Response to SARS-CoV-2 in Relation to the Contributing Factors in COVID-19 Patients. Viral Immunol 2022; 35:142-149. [PMID: 35167759 DOI: 10.1089/vim.2021.0097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Human health has always been challenged by variety of viral infections, but severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has surpassed all previous viral diseases and emerged as a major health challenge around the globe. Real-time polymerase chain reaction (PCR) is the gold standard for the diagnosis of SARS-CoV-2 and serological assay provides a compliment to diagnosis after second week of infection. The aim of the study is the characterization of antibody response to SARS-CoV-2 in the blood sample of diagnosed coronavirus disease 2019 (COVID-19) patients, and its potential association with factors such as age, gender, time, and symptoms. Serum from 248 confirmed SARS-CoV-2 patients was investigated for antibodies. Elecsys anti-SARS chemiluminescent immune assay was performed for the detection of nucleocapsid-specific antibodies. Association of antibody response with gender, age, and time after onset of symptoms was analyzed. Among 248 PCR positive SARS-CoV-2 patients, 214 (86.3%) have virus-specific antibody signals. Antibodies positivity rate was higher in male patient patients as compared with female patients (90.8% vs. 79.2%, p = 0.009). Patients aged 30-40 years had the highest antibody positivity rate as compared with other groups (89.10%, p = 0.04). Patients age group >60 years had a lower positivity rate (75%, p = 0.04). The increasing trend in the antibodies detection with time was observed, maximum positive antibodies response rate observed at 8 weeks. Patients were categorized on the basis of clinical symptoms into asymptomatic, mild, and moderate; 17.7% were asymptomatic, 60.5% showed mild symptoms, and 21.8% showed moderate symptoms of the disease. Males were seen to be more asymptomatic as compared with females (i.e., 59.1% to 40.9%). The serological test for SARS-CoV-2 has a high sensitivity at >2 weeks after the positive PCR result or onset of illness. In addition, the serological response differs among patients based on gender, age, as well as time between the onset of symptoms or PCR confirmation and sample collection for the study of antibody response.
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Affiliation(s)
- Hafsa Aziz
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | - Shazia Fatima
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | - Humera Mahmood
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | | | | | - Shaista Khurshid
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | - Wardah Aslam
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | - Saeeda Aziz
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
| | - Mohammad Faheem
- Nuclear Medicine, Oncology and Radiotherapy Institute, Islamabad, Pakistan
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10
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Bukh J. Neutralizing Antibodies Against Hepatitis C Virus and Their Role in Vaccine Immunity. Gastroenterology 2022; 162:396-398. [PMID: 34863787 DOI: 10.1053/j.gastro.2021.11.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 01/10/2023]
Affiliation(s)
- Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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11
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Echeverría N, Comas V, Aldunate F, Perbolianachis P, Moreno P, Cristina J. In the era of rapid mRNA-based vaccines: Why is there no effective hepatitis C virus vaccine yet? World J Hepatol 2021; 13:1234-1268. [PMID: 34786164 PMCID: PMC8568586 DOI: 10.4254/wjh.v13.i10.1234] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/14/2021] [Accepted: 09/10/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is responsible for no less than 71 million people chronically infected and is one of the most frequent indications for liver transplantation worldwide. Despite direct-acting antiviral therapies fuel optimism in controlling HCV infections, there are several obstacles regarding treatment accessibility and reinfection continues to remain a possibility. Indeed, the majority of new HCV infections in developed countries occur in people who inject drugs and are more plausible to get reinfected. To achieve global epidemic control of this virus the development of an effective prophylactic or therapeutic vaccine becomes a must. The coronavirus disease 19 (COVID-19) pandemic led to auspicious vaccine development against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, which has renewed interest on fighting HCV epidemic with vaccination. The aim of this review is to highlight the current situation of HCV vaccine candidates designed to prevent and/or to reduce HCV infectious cases and their complications. We will emphasize on some of the crossroads encountered during vaccine development against this insidious virus, together with some key aspects of HCV immunology which have, so far, hampered the progress in this area. The main focus will be on nucleic acid-based as well as recombinant viral vector-based vaccine candidates as the most novel vaccine approaches, some of which have been recently and successfully employed for SARS-CoV-2 vaccines. Finally, some ideas will be presented on which methods to explore for the design of live-attenuated vaccines against HCV.
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Affiliation(s)
- Natalia Echeverría
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Victoria Comas
- Departamento de Desarrollo Biotecnológico, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
| | - Fabián Aldunate
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Paula Perbolianachis
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Pilar Moreno
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Juan Cristina
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay.
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12
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Dobrica M, van Eerde A, Tucureanu C, Onu A, Paruch L, Caras I, Vlase E, Steen H, Haugslien S, Alonzi D, Zitzmann N, Bock R, Dubuisson J, Popescu C, Stavaru C, Liu Clarke J, Branza‐Nichita N. Hepatitis C virus E2 envelope glycoprotein produced in Nicotiana benthamiana triggers humoral response with virus-neutralizing activity in vaccinated mice. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:2027-2039. [PMID: 34002936 PMCID: PMC8486241 DOI: 10.1111/pbi.13631] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 04/27/2021] [Accepted: 05/13/2021] [Indexed: 05/03/2023]
Abstract
Chronic infection with hepatitis C virus (HCV) remains a leading cause of liver-related pathologies and a global health problem, currently affecting more than 71 million people worldwide. The development of a prophylactic vaccine is much needed to complement the effective antiviral treatment available and achieve HCV eradication. Current strategies focus on increasing the immunogenicity of the HCV envelope glycoprotein E2, the major target of virus-neutralizing antibodies, by testing various expression systems or manipulating the protein conformation and the N-glycosylation pattern. Here we report the first evidence of successful production of the full-length HCV E2 glycoprotein in Nicotiana benthamiana, by using the Agrobacterium-mediated transient expression technology. Molecular and functional analysis showed that the viral protein was correctly processed in plant cells and achieved the native folding required for binding to CD81, one of the HCV receptors. N-glycan analysis of HCV-E2 produced in N. benthamiana and mammalian cells indicated host-specific trimming of mannose residues and possibly, protein trafficking. Notably, the plant-derived viral antigen triggered a significant immune response in vaccinated mice, characterized by the presence of antibodies with HCV-neutralizing activity. Together, our study demonstrates that N. benthamiana is a viable alternative to costly mammalian cell cultures for the expression of complex viral antigens and supports the use of plants as cost-effective production platforms for the development of HCV vaccines.
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Affiliation(s)
| | | | - Catalin Tucureanu
- Cantacuzino” Medico‐Military National Research InstituteBucharestRomania
| | - Adrian Onu
- Cantacuzino” Medico‐Military National Research InstituteBucharestRomania
| | - Lisa Paruch
- NIBIO ‐ Norwegian Institute of Bioeconomy ResearchÅsNorway
| | - Iuliana Caras
- Cantacuzino” Medico‐Military National Research InstituteBucharestRomania
| | - Ene Vlase
- Cantacuzino” Medico‐Military National Research InstituteBucharestRomania
| | - Hege Steen
- NIBIO ‐ Norwegian Institute of Bioeconomy ResearchÅsNorway
| | | | - Dominic Alonzi
- Oxford Glycobiology InstituteDepartment of BiochemistryUniversity of OxfordOxfordUK
| | - Nicole Zitzmann
- Oxford Glycobiology InstituteDepartment of BiochemistryUniversity of OxfordOxfordUK
| | - Ralph Bock
- Max Planck Institute of Molecular Plant PhysiologyPotsdam‐GolmGermany
| | - Jean Dubuisson
- Université LilleCNRSINSERMCHU LilleInstitut Pasteur de LilleU1019‐UMR 9017‐CIIL‐Center for Infection and Immunity of LilleLilleFrance
| | | | - Crina Stavaru
- Cantacuzino” Medico‐Military National Research InstituteBucharestRomania
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13
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Characterization of linear epitope specificity of antibodies potentially contributing to spontaneous clearance of hepatitis C virus. PLoS One 2021; 16:e0256816. [PMID: 34449828 PMCID: PMC8396737 DOI: 10.1371/journal.pone.0256816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 08/16/2021] [Indexed: 11/19/2022] Open
Abstract
Background Around 30% of the HCV infected patients can spontaneously clear the virus. Cumulative evidence suggests the role of neutralizing antibodies in such spontaneous resolution. Understanding the epitope specificity of such antibodies will inform the rational vaccine design as such information is limited to date. In addition to conformational epitope targeted antibodies, linear epitope specific antibodies have been identified that are broadly cross reactive against diverse HCV strains. In this study, we have characterized the potential role of three conserved linear epitopes in the spontaneous clearance of HCV. Methods We tested the reactivity of sera from chronic patients (CP) and spontaneous resolvers (SR) with linear peptides corresponding to three conserved regions of HCV envelope protein E2 spanning amino acids 412–423, 523–532 and 432–443 using ELISA. Subsequently, we characterized the dependency of HCV neutralization by the reactive serum samples on the antibodies specific for these epitopes using pseudoparticle-based neutralization assay. In ELISA most of the CP sera showed reactivity to multiple peptides while most of the SR samples were reactive to a single peptide suggesting presence of more specific antibodies in the SR sera. In most of the HCVpp neutralizing sera of particular peptide reactivity the neutralization was significantly affected by the presence of respective peptide. HCV neutralization by CP sera was affected by multiple peptides while 75% of the HCVpp neutralizing SR sera were competed by the 432 epitope. Conclusions These findings suggest that individuals who spontaneously resolve HCV infection at the acute phase, can produce antibodies specific for conserved linear epitopes, and those antibodies can potentially play a role in the spontaneous viral clearance. The epitope present in the 432–443 region of E2 was identified as the primary neutralizing epitope with potential role in spontaneous viral clearance and this epitope potentiates for the design of immunogen for prophylactic vaccine.
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14
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Where to Next? Research Directions after the First Hepatitis C Vaccine Efficacy Trial. Viruses 2021; 13:v13071351. [PMID: 34372558 PMCID: PMC8310243 DOI: 10.3390/v13071351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/03/2021] [Accepted: 07/08/2021] [Indexed: 11/17/2022] Open
Abstract
Thirty years after its discovery, the hepatitis C virus (HCV) remains a leading cause of liver disease worldwide. Given that many countries continue to experience high rates of transmission despite the availability of potent antiviral therapies, an effective vaccine is seen as critical for the elimination of HCV. The recent failure of the first vaccine efficacy trial for the prevention of chronic HCV confirmed suspicions that this virus will be a challenging vaccine target. Here, we examine the published data from this first efficacy trial along with the earlier clinical and pre-clinical studies of the vaccine candidate and then discuss three key research directions expected to be important in ongoing and future HCV vaccine development. These include the following: 1. design of novel immunogens that generate immune responses to genetically diverse HCV genotypes and subtypes, 2. strategies to elicit broadly neutralizing antibodies against envelope glycoproteins in addition to cytotoxic and helper T cell responses, and 3. consideration of the unique immunological status of individuals most at risk for HCV infection, including those who inject drugs, in vaccine platform development and early immunogenicity trials.
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15
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Kardani K, Sadat SM, Kardani M, Bolhassani A. The next generation of HCV vaccines: a focus on novel adjuvant development. Expert Rev Vaccines 2021; 20:839-855. [PMID: 34114513 DOI: 10.1080/14760584.2021.1941895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Considerable efforts have been made to treat and prevent acute and chronic infections caused by the hepatitis C virus (HCV). Current treatments are unable to protect people from reinfection. Hence, there is a need for development of both preventive and therapeutic HCV vaccines. Many vaccine candidates are in development to fight against HCV, but their efficacy has so far proven limited partly due to low immunogenicity. AREAS COVERED We explore development of novel and powerful adjuvants to achieve an effective HCV vaccine. The basis for developing strong adjuvants is to understand the innate immunity pathway, which subsequently stimulates humoral and cellular immune responses. We have also investigated immunogenicity of developed adjuvants that have been used in recent studies available in online databases such as PubMed, PMC, ScienceDirect, Google Scholar, etc. EXPERT OPINION Adjuvants are used as a part of vaccine formulation to boost vaccine immunogenicity and antigen delivery. Several FDA-approved adjuvants are used in licensed human vaccines. Unfortunately, no adjuvant has yet been proven to boost HCV immune responses to the extent needed for an effective vaccine. One of the promising approaches for developing an effective adjuvant is the combination of various adjuvants to trigger several innate immune responses, leading to activation of adaptive immunity.[Figure: see text].
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Affiliation(s)
- Kimia Kardani
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Mehdi Sadat
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | - Mona Kardani
- Iranian Comprehensive Hemophilia Care Center, Tehran, Iran
| | - Azam Bolhassani
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
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16
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Kalemera MD, Capella-Pujol J, Chumbe A, Underwood A, Bull RA, Schinkel J, Sliepen K, Grove J. Optimized cell systems for the investigation of hepatitis C virus E1E2 glycoproteins. J Gen Virol 2021; 102. [PMID: 33147126 PMCID: PMC8116788 DOI: 10.1099/jgv.0.001512] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Great strides have been made in understanding and treating hepatitis C virus (HCV) thanks to the development of various experimental systems including cell-culture-proficient HCV, the HCV pseudoparticle system and soluble envelope glycoproteins. The HCV pseudoparticle (HCVpp) system is a platform used extensively in studies of cell entry, screening of novel entry inhibitors, assessing the phenotypes of clinically observed E1 and E2 glycoproteins and, most pertinently, in characterizing neutralizing antibody breadth induced upon vaccination and natural infection in patients. Nonetheless, some patient-derived clones produce pseudoparticles that are either non-infectious or exhibit infectivity too low for meaningful phenotyping. The mechanisms governing whether any particular clone produces infectious pseudoparticles are poorly understood. Here we show that endogenous expression of CD81, an HCV receptor and a cognate-binding partner of E2, in producer HEK 293T cells is detrimental to the infectivity of recovered HCVpp for most strains. Many HCVpp clones exhibited increased infectivity or had their infectivity rescued when they were produced in 293T cells CRISPR/Cas9 engineered to ablate CD81 expression (293TCD81KO). Clones made in 293TCD81KO cells were antigenically very similar to their matched counterparts made parental cells and appear to honour the accepted HCV entry pathway. Deletion of CD81 did not appreciably increase the recovered titres of soluble E2 (sE2). However, we did, unexpectedly, find that monomeric sE2 made in 293T cells and Freestyle 293-F (293-F) cells exhibit important differences. We found that 293-F-produced sE2 harbours mostly complex-type glycans whilst 293T-produced sE2 displays a heterogeneous mixture of both complex-type glycans and high-mannose or hybrid-type glycans. Moreover, sE2 produced in 293T cells is antigenically superior; exhibiting increased binding to conformational antibodies and the large extracellular loop of CD81. In summary, this work describes an optimal cell line for the production of HCVpp and reveals that sE2 made in 293T and 293-F cells are not antigenic equals. Our findings have implications for functional studies of E1E2 and the production of candidate immunogens.
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Affiliation(s)
- Mphatso D Kalemera
- Institute of Immunity and Transplantation, Division of Infection and Immunity, The Royal Free Hospital, University College London, London, UK
| | - Joan Capella-Pujol
- Department of Medical Microbiology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - Ana Chumbe
- Department of Medical Microbiology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - Alexander Underwood
- Viral Immunology Systems Program, The Kirby Institute, School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, Australia
| | - Rowena A Bull
- Viral Immunology Systems Program, The Kirby Institute, School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, Australia
| | - Janke Schinkel
- Department of Medical Microbiology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - Kwinten Sliepen
- Department of Medical Microbiology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - Joe Grove
- Institute of Immunity and Transplantation, Division of Infection and Immunity, The Royal Free Hospital, University College London, London, UK
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17
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From Structural Studies to HCV Vaccine Design. Viruses 2021; 13:v13050833. [PMID: 34064532 PMCID: PMC8147963 DOI: 10.3390/v13050833] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/21/2021] [Accepted: 04/28/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a serious and growing public health problem despite recent developments of antiviral therapeutics. To achieve global elimination of HCV, an effective cross-genotype vaccine is needed. The failure of previous vaccination trials to elicit an effective cross-reactive immune response demands better vaccine antigens to induce a potent cross-neutralizing response to improve vaccine efficacy. HCV E1 and E2 envelope (Env) glycoproteins are the main targets for neutralizing antibodies (nAbs), which aid in HCV clearance and protection. Therefore, a molecular-level understanding of the nAb responses against HCV is imperative for the rational design of cross-genotype vaccine antigens. Here we summarize the recent advances in structural studies of HCV Env and Env-nAb complexes and how they improve our understanding of immune recognition of HCV. We review the structural data defining HCV neutralization epitopes and conformational plasticity of the Env proteins, and the knowledge applicable to rational vaccine design.
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18
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Abstract
Antibody responses in hepatitis C virus (HCV) have been a rather mysterious research topic for many investigators working in the field. Chronic HCV infection is often associated with dysregulation of immune functions particularly in B cells, leading to abnormal lymphoproliferation or the production of autoantibodies that exacerbate inflammation and extrahepatic diseases. When considering the antiviral function of antibody, it was difficult to endorse its role in HCV protection, whereas T-cell response has been shown unequivocally critical for natural recovery. Recent breakthroughs in the study of HCV and antigen-specific antibody responses provide important insights into viral vulnerability to antibodies and the immunogenetic and structural properties of the neutralizing antibodies. The new knowledge reinvigorates HCV vaccine research by illuminating a new path for the rational design of vaccine antigens to elicit broadly neutralizing antibodies for protection.
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Affiliation(s)
- Mansun Law
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California 92109, USA
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19
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Immune system control of hepatitis C virus infection. Curr Opin Virol 2020; 46:36-44. [PMID: 33137689 DOI: 10.1016/j.coviro.2020.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/11/2020] [Indexed: 12/20/2022]
Abstract
Hepatitis C virus (HCV) remains a global public health problem even though more than 95% of infections can be cured by treatment with direct-acting antiviral agents. Resolution of viremia post antiviral therapy does not lead to protective immunity and therefore reinfections can occur. Immune cell detection of HCV activates signaling pathways that produce interferons and trigger the innate immune response against the virus, preventing HCV replication and spread. Cells in the innate immune system, including natural killer, dendritic, and Kupffer cells, interact with infected hepatocytes and present viral antigens to T and B cells where their effector responses contribute to infection outcome. Despite the immune activation, HCV can evade the host response and establish persistent infection. Plans to understand the correlates of protection and strategies to activate proper innate and adaptive immune responses are needed for development of an effective prophylactic vaccine that stimulates protective immunity and limits HCV transmission.
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20
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Abstract
Protective vaccines for hypervariable pathogens are urgently needed. It has been proposed that amputating highly variable epitopes from vaccine antigens would induce the production of broadly protective antibodies targeting conserved epitopes. However, so far, these approaches have failed, partially because conserved epitopes are occluded in vivo and partially because co-localizing patterns of immunodominance and antigenic variability render variable epitopes the primary target for antibodies in natural infection. In this Perspective, to recast the challenge of vaccine development for hypervariable pathogens, I evaluate convergent mechanisms of adaptive variation, such as intrahost immune-mediated diversification, spatiotemporally defined antigenic space, and infection-enhancing cross-immunoreactivity. The requirements of broadly protective immune responses targeting variable pathogens are formulated in terms of cross-immunoreactivity, stoichiometric thresholds for neutralization, and the elicitation of antibodies targeting physicochemically conserved signatures within sequence variable domains.
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Affiliation(s)
- Alexander I Mosa
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
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21
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Mina M, Underwood A, Eltahla A, Wu BR, Walker MR, Bull RA, Lloyd AR. Anti-envelope antibody responses in highly exposed seronegative individuals may be associated with protection from HCV infection. J Viral Hepat 2020; 27:1012-1021. [PMID: 32497370 DOI: 10.1111/jvh.13339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 05/11/2020] [Indexed: 12/09/2022]
Abstract
In rare cases, individuals with a history of long-term injecting drug use remain seronegative and aviraemic, despite prolonged and likely repeated exposure to Hepatitis C virus (HCV) through high-risk behaviour. We describe anti-HCV Envelope (E) antibody responses in a prospective cohort of carefully defined highly exposed but uninfected subjects (HESN) and comparison subjects who were also high risk and uninfected, but rapidly became HCV infected (Incident). Longitudinally collected samples from HESN cases (n = 22) were compared to Incident controls (n = 22). IgG, IgM and IgA from sera were tested by ELISA to genotype 1a and 3a E glycoproteins, and recombinant genotype 1a E2 antigen. IgG subclass isotyping was performed for those positive for IgG. Virus-neutralizing activity was assessed on HCV pseudoparticles, and HCV E-specific B cells analysed using flow cytometry. A significant minority of HESN cases (n = 10; 45%) had anti-E, predominantly in the IgG2 subclass, which was not found in the pre-infection time point of the Incident cases (n = 1; 5%). A subset of the HESN subjects also had neutralizing activity and HCV-specific B cells detected significantly more than Incident cases pre-infection. In conclusion, the HESN phenotype is associated with IgG2 anti-E antibodies, neutralization activity and HCV E-specific memory B cells. These findings suggest that HESN subjects may be resistant to HCV infection through humoral immune-mediated mechanisms.
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Affiliation(s)
- Michael Mina
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Alexander Underwood
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Auda Eltahla
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Bing-Ru Wu
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Melanie R Walker
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Rowena A Bull
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| | - Andrew R Lloyd
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, New South Wales, Australia
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22
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Ströh LJ, Krey T. HCV Glycoprotein Structure and Implications for B-Cell Vaccine Development. Int J Mol Sci 2020; 21:ijms21186781. [PMID: 32947858 PMCID: PMC7555785 DOI: 10.3390/ijms21186781] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/12/2020] [Accepted: 09/14/2020] [Indexed: 02/06/2023] Open
Abstract
Despite the approval of highly efficient direct-acting antivirals in the last decade Hepatitis C virus (HCV) remains a global health burden and the development of a vaccine would constitute an important step towards the control of HCV. The high genetic variability of the viral glycoproteins E1 and E2, which carry the main neutralizing determinants, together with their intrinsic structural flexibility, the high level of glycosylation that shields conserved neutralization epitopes and immune evasion using decoy epitopes renders the design of an efficient vaccine challenging. Recent structural and functional analyses have highlighted the role of the CD81 receptor binding site on E2, which overlaps with those neutralization epitopes within E2 that have been structurally characterized to date. This CD81 binding site consists of three distinct segments including “epitope I”, “epitope II” and the “CD81 binding loop”. In this review we summarize the structural features of the HCV glycoproteins that have been derived from X-ray structures of neutralizing and non-neutralizing antibody fragments complexed with either recombinant E2 or epitope-derived linear peptides. We focus on the current understanding how neutralizing antibodies interact with their cognate antigen, the structural features of the respective neutralization epitopes targeted by nAbs and discuss the implications for informed vaccine design.
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Affiliation(s)
- Luisa J. Ströh
- Institute of Virology, Hannover Medical School, 30625 Hannover, Germany;
| | - Thomas Krey
- Institute of Virology, Hannover Medical School, 30625 Hannover, Germany;
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, 23562 Luebeck, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Luebeck-Borstel-Riems, 23562 Luebeck, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, 30625 Hannover, Germany
- Centre for Structural Systems Biology (CSSB), 22607 Hamburg, Germany
- Correspondence: ; Tel.: +49-(0)451–3101-3101
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23
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Hepatitis C virus vaccine design: focus on the humoral immune response. J Biomed Sci 2020; 27:78. [PMID: 32631318 PMCID: PMC7338099 DOI: 10.1186/s12929-020-00669-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 06/26/2020] [Indexed: 02/06/2023] Open
Abstract
Despite the recent development of safe and highly effective direct-acting antivirals, hepatitis C virus (HCV) infection remains a significant health problem. In 2016, the World Health Organization set out to reduce the rate of new HCV infections by 90% by 2030. Still, global control of the virus does not seem to be achievable in the absence of an effective vaccine. Current approaches to the development of a vaccine against HCV include the production of recombinant proteins, synthetic peptides, DNA vaccines, virus-like particles, and viral vectors expressing various antigens. In this review, we focus on the development of vaccines targeting the humoral immune response against HCV based on the cumulative evidence supporting the important role of neutralizing antibodies in protection against HCV infection. The main targets of HCV-specific neutralizing antibodies are the glycoproteins E1 and E2. Recent advances in the knowledge of HCV glycoprotein structure and their epitopes, as well as the possibility of getting detailed information on the human antibody repertoire generated by the infection, will allow rational structure-based antigen design to target specific germline antibodies. Although obtaining a vaccine capable of inducing sterilizing immunity will be a difficult task, a vaccine that prevents chronic hepatitis C infections, a more realistic goal in the short term, would have a considerable health impact.
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24
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Association of the Sialylation of Antibodies Specific to the HCV E2 Envelope Glycoprotein with Hepatic Fibrosis Progression and Antiviral Therapy Efficacy. DISEASE MARKERS 2020; 2020:8881279. [PMID: 32685058 PMCID: PMC7333057 DOI: 10.1155/2020/8881279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 05/27/2020] [Accepted: 06/05/2020] [Indexed: 12/30/2022]
Abstract
The E2 envelope glycoprotein of the hepatitis C virus (HCV) is a major target of broadly neutralizing antibodies that are closely related to a spontaneous cure of HCV infection. There is still no data about the diversity of E2-specific antibodies (Abs) glycosylation. The aim of this study was to analyze the level and sialylation of E2 IgG Abs, the relation of the respective changes to hepatic fibrosis (F) progression and their possible association with the efficacy of interferon-α-2a plus ribavirin (IFN-RBV) antiviral therapy. One hundred three HCV infected treatment-naive patients were examined using ELISA with E2 recombinant protein as antigen and sialic acid-specific Sambucus nigra agglutinin. The efficacy of the IFN-RBV treatment of patients with HCV dominant 1b and 3a genotypes (GT) was evaluated. A significant decrease of E2 Abs sialylation in the late stages of fibrosis was found irrespective of HCV genotype. On this basis, the F4 stage of fibrosis can be discriminated from its F0 or F1-3 stage by an about 75-79% accuracy. HCV infection of 1b genotype is associated with the production of lower sialylated E2 Abs, a higher frequency of F4 stage fibrosis, and a worse response to antiviral therapy. The increased SNA reactivity of E2 Abs was observed in patients with a sustained virological response (SVR). The proportion of SVR responders was significantly higher among patients with 3a genotype. However, for both dominant HCV genotypes (3a and 1b), an increased sialylation of E2 IgG was associated with a higher rate of patients with sustained virological response to antiviral therapy. Thus, the association of alterations of anti-E2 IgG Abs sialylation with hepatic fibrosis stage, HCV genotype, and the efficacy of antiviral therapy enables using these changes as novel noninvasive predictive biomarkers. The clinical potential of these findings is discussed.
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25
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Dash S, Aydin Y, Widmer KE, Nayak L. Hepatocellular Carcinoma Mechanisms Associated with Chronic HCV Infection and the Impact of Direct-Acting Antiviral Treatment. J Hepatocell Carcinoma 2020; 7:45-76. [PMID: 32346535 PMCID: PMC7167284 DOI: 10.2147/jhc.s221187] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 03/06/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) infection is the major risk factor for liver cirrhosis and hepatocellular carcinoma (HCC). The mechanisms of HCC initiation, growth, and metastasis appear to be highly complex due to the decade-long interactions between the virus, immune system, and overlapping bystander effects of host metabolic liver disease. The lack of a readily accessible animal model system for HCV is a significant obstacle to understand the mechanisms of viral carcinogenesis. Traditionally, the primary prevention strategy of HCC has been to eliminate infection by antiviral therapy. The success of virus elimination by antiviral treatment is determined by the SVR when the HCV is no longer detectable in serum. Interferon-alpha (IFN-α) and its analogs, pegylated IFN-α (PEG-IFN-α) alone with ribavirin (RBV), have been the primary antiviral treatment of HCV for many years with a low cure rate. The cloning and sequencing of HCV have allowed the development of cell culture models, which accelerated antiviral drug discovery. It resulted in the selection of highly effective direct-acting antiviral (DAA)-based combination therapy that now offers incredible success in curing HCV infection in more than 95% of all patients, including those with cirrhosis. However, several emerging recent publications claim that patients who have liver cirrhosis at the time of DAAs treatment face the risk of HCC occurrence and recurrence after viral cure. This remains a substantial challenge while addressing the long-term benefit of antiviral medicine. The host-related mechanisms that drive the risk of HCC in the absence of the virus are unknown. This review describes the multifaceted mechanisms that create a tumorigenic environment during chronic HCV infection. In addition to the potential oncogenic programming that drives HCC after viral clearance by DAAs, the current status of a biomarker development for early prediction of cirrhosis regression and HCC detection post viral treatment is discussed. Since DAAs treatment does not provide full protection against reinfection or viral transmission to other individuals, the recent studies for a vaccine development are also reviewed.
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Affiliation(s)
- Srikanta Dash
- Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, New Orleans, LA70112, USA
- Southeast Louisiana Veterans Health Care System, New Orleans, LA70119, USA
- Department of Medicine, Division of Gastroenterology, Tulane University Health Sciences Center, New Orleans, LA70112, USA
| | - Yucel Aydin
- Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, New Orleans, LA70112, USA
| | - Kyle E Widmer
- Southeast Louisiana Veterans Health Care System, New Orleans, LA70119, USA
| | - Leela Nayak
- Southeast Louisiana Veterans Health Care System, New Orleans, LA70119, USA
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Duncan JD, Urbanowicz RA, Tarr AW, Ball JK. Hepatitis C Virus Vaccine: Challenges and Prospects. Vaccines (Basel) 2020; 8:vaccines8010090. [PMID: 32079254 PMCID: PMC7157504 DOI: 10.3390/vaccines8010090] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/25/2020] [Accepted: 02/04/2020] [Indexed: 02/07/2023] Open
Abstract
The hepatitis C virus (HCV) causes both acute and chronic infection and continues to be a global problem despite advances in antiviral therapeutics. Current treatments fail to prevent reinfection and remain expensive, limiting their use to developed countries, and the asymptomatic nature of acute infection can result in individuals not receiving treatment and unknowingly spreading HCV. A prophylactic vaccine is therefore needed to control this virus. Thirty years since the discovery of HCV, there have been major gains in understanding the molecular biology and elucidating the immunological mechanisms that underpin spontaneous viral clearance, aiding rational vaccine design. This review discusses the challenges facing HCV vaccine design and the most recent and promising candidates being investigated.
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Affiliation(s)
- Joshua D. Duncan
- School of Life Sciences, The University of Nottingham, Nottingham NG7 2UH, UK; (R.A.U.); (A.W.T.); (J.K.B.)
- NIHR Nottingham BRC, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham NG7 2UH, UK
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
- Correspondence:
| | - Richard A. Urbanowicz
- School of Life Sciences, The University of Nottingham, Nottingham NG7 2UH, UK; (R.A.U.); (A.W.T.); (J.K.B.)
- NIHR Nottingham BRC, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham NG7 2UH, UK
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - Alexander W. Tarr
- School of Life Sciences, The University of Nottingham, Nottingham NG7 2UH, UK; (R.A.U.); (A.W.T.); (J.K.B.)
- NIHR Nottingham BRC, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham NG7 2UH, UK
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - Jonathan K. Ball
- School of Life Sciences, The University of Nottingham, Nottingham NG7 2UH, UK; (R.A.U.); (A.W.T.); (J.K.B.)
- NIHR Nottingham BRC, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham NG7 2UH, UK
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
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Envelope-Specific IgG3 and IgG1 Responses Are Associated with Clearance of Acute Hepatitis C Virus Infection. Viruses 2020; 12:v12010075. [PMID: 31936235 PMCID: PMC7019651 DOI: 10.3390/v12010075] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/18/2019] [Accepted: 01/06/2020] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C virus (HCV) can be cleared naturally in a subset of individuals. However, the asymptomatic nature of acute HCV infection makes the study of the early immune response and defining the correlates of protection challenging. Despite this, there is now strong evidence implicating the humoral immune response, specifically neutralising antibodies, in determining the clearance or chronicity outcomes of primary HCV infection. In general, immunoglobulin G (IgG) plays the major role in viral neutralisation. However, there are limited investigations of anti-HCV envelope protein 2 (E2) isotypes (IgM, IgG, IgA) and IgG subclasses (IgG1-4) in early HCV infection. In this study, using a rare cohort of 14 very recently HCV-infected individuals (4-45 days) with varying disease outcome (n = 7 clearers), the timing and potency of anti-HCV E2 isotypes and IgG subclasses were examined longitudinally, in relation to neutralising antibody activity. Clearance was associated with anti-E2 IgG, specifically IgG1 and IgG3, and appeared essential to prevent the emergence of new HCV variants and the chronic infection outcome. Interestingly, these IgG responses were accompanied by IgM antibodies and were associated with neutralising antibody activity in the subjects who cleared infection. These findings provide novel insights into the early humoral immune response characteristics associated with HCV disease outcome.
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