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Chan M, Warner BM, Audet J, Barker D, Tailor N, Vendramelli R, Truong T, Tierney K, Boese AS, Qiu H, Holtsberg FW, Aman J, Kodihalli S, Kobasa D. Delayed treatment of cynomolgus macaques with a FVM04/CA45 monoclonal antibody cocktail provides complete protection against lethal Sudan virus infection. J Virol 2024; 98:e0124223. [PMID: 39012096 PMCID: PMC11334508 DOI: 10.1128/jvi.01242-23] [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: 09/05/2023] [Accepted: 06/10/2024] [Indexed: 07/17/2024] Open
Abstract
Sudan ebolavirus (SUDV) is a member of the genus Ebolavirus (Family Filoviridae) and has caused sporadic outbreaks of Ebola disease (EBOD), or more specifically Sudan virus disease (SVD), with high mortality rates in Africa. Current vaccines and therapies that have been developed for filoviruses are almost all specific for Ebola virus (EBOV; of the species Zaire ebolavirus), and there is a current lack of therapeutics specific for SUDV. The recent SUDV outbreak in Uganda, which was distributed across multiple districts, including Kampala, a densely populated urban center, highlights the critical need for the development of novel SUDV-specific or pan-Ebola virus therapeutics. Previous work has characterized two monoclonal antibodies, FVM04 and CA45, which have neutralization capabilities against both EBOV and SUDV and have shown protective efficacy in animal challenge studies. Here, we expand upon this work, showing that treatment with a monoclonal antibody cocktail consisting of FVM04 and CA45 provides full protection against lethal SUDV infection in cynomolgus macaques. Studies that evaluate outcomes at late time points after infection, once clinical signs of illness are apparent, are vital for assessing the therapeutic efficacy of antibody therapeutics. We have shown that when treatment is initiated as late as 5 days after infection, with a second dose given on day 8, that treated groups showed few clinical signs or morbidity, with complete survival. This work provides further evidence that FVM04 and CA45 have strong therapeutic potential against SUDV and their development as a pan-Ebola virus therapeutic should be pursued. IMPORTANCE There are currently no approved vaccines or therapeutics for Sudan virus, a filovirus which is highly related to Ebola virus and causes similar disease and outbreaks. In this study, a cocktail of two potent monoclonal antibodies that effectively neutralize Sudan virus was tested in a nonhuman primate model of Sudan virus disease. Treatment was highly effective, even when initiated as late as 5 days after infection, when clinical signs of infection were already evident. All treated animals showed complete recovery from infection, with little evidence of disease, while all animals that received a control treatment succumbed to infection within 8 days. The study further demonstrated the strong therapeutic potential of the antibody treatment and supported further development for use in Sudan virus outbreaks.
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MESH Headings
- Animals
- Female
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Neutralizing/immunology
- Antibodies, Neutralizing/therapeutic use
- Antibodies, Viral/immunology
- Antibodies, Viral/therapeutic use
- Disease Models, Animal
- Ebolavirus/immunology
- Hemorrhagic Fever, Ebola/prevention & control
- Hemorrhagic Fever, Ebola/immunology
- Hemorrhagic Fever, Ebola/drug therapy
- Macaca fascicularis
- Treatment Delay
- Male
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Affiliation(s)
- Mable Chan
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Bryce M. Warner
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Jonathan Audet
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Douglas Barker
- Research and Development, Emergent BioSolutions Canada, Winnipeg, Manitoba, Canada
| | - Nikesh Tailor
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Robert Vendramelli
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Thang Truong
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Kevin Tierney
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Amrit S. Boese
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Honguy Qiu
- Research and Development, Emergent BioSolutions Canada, Winnipeg, Manitoba, Canada
| | | | - Javad Aman
- Integrated BioTherapeutics, Rockville, Maryland, USA
| | - Shantha Kodihalli
- Research and Development, Emergent BioSolutions Canada, Winnipeg, Manitoba, Canada
| | - Darwyn Kobasa
- Special Pathogens program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Canada
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2
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Janus BM, Wang R, Cleveland TE, Metcalf MC, Lemmer AC, van Dyk N, Jeong S, Astavans A, Class K, Fuerst TR, Ofek G. Macaque antibodies targeting Marburg virus glycoprotein induced by multivalent immunization. J Virol 2024; 98:e0015524. [PMID: 38832790 PMCID: PMC11329191 DOI: 10.1128/jvi.00155-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/07/2024] [Indexed: 06/05/2024] Open
Abstract
Marburg virus infection in humans is associated with case fatality rates that can reach up to 90%, but to date, there are no approved vaccines or monoclonal antibody (mAb) countermeasures. Here, we immunized Rhesus macaques with multivalent combinations of filovirus glycoprotein (GP) antigens belonging to Marburg, Sudan, and Ebola viruses to generate monospecific and cross-reactive antibody responses against them. From the animal that developed the highest titers of Marburg virus GP-specific neutralizing antibodies, we sorted single memory B cells using a heterologous Ravn virus GP probe and cloned and characterized a panel of 34 mAbs belonging to 28 unique lineages. Antibody specificities were assessed by overlapping pepscan and binding competition analyses, revealing that roughly a third of the lineages mapped to the conserved receptor binding region, including potent neutralizing lineages that were confirmed by negative stain electron microscopy to target this region. Additional lineages targeted a protective region on GP2, while others were found to possess cross-filovirus reactivity. Our study advances the understanding of orthomarburgvirus glycoprotein antigenicity and furthers efforts to develop candidate antibody countermeasures against these lethal viruses. IMPORTANCE Marburg viruses were the first filoviruses characterized to emerge in humans in 1967 and cause severe hemorrhagic fever with average case fatality rates of ~50%. Although mAb countermeasures have been approved for clinical use against the related Ebola viruses, there are currently no approved countermeasures against Marburg viruses. We successfully isolated a panel of orthomarburgvirus GP-specific mAbs from a macaque immunized with a multivalent combination of filovirus antigens. Our analyses revealed that roughly half of the antibodies in the panel mapped to regions on the glycoprotein shown to protect from infection, including the host cell receptor binding domain and a protective region on the membrane-anchoring subunit. Other antibodies in the panel exhibited broad filovirus GP recognition. Our study describes the discovery of a diverse panel of cross-reactive macaque antibodies targeting orthomarburgvirus and other filovirus GPs and provides candidate immunotherapeutics for further study and development.
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Affiliation(s)
- Benjamin M Janus
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Ruixue Wang
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Thomas E Cleveland
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Matthew C Metcalf
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Aaron C Lemmer
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | - Nydia van Dyk
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Sarah Jeong
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Anagh Astavans
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | - Kenneth Class
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | - Thomas R Fuerst
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
| | - Gilad Ofek
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
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3
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Tam EH, Peng Y, Cheah MXY, Yan C, Xiao T. Neutralizing antibodies to block viral entry and for identification of entry inhibitors. Antiviral Res 2024; 224:105834. [PMID: 38369246 DOI: 10.1016/j.antiviral.2024.105834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/01/2024] [Accepted: 02/07/2024] [Indexed: 02/20/2024]
Abstract
Neutralizing antibodies (NAbs) are naturally produced by our immune system to combat viral infections. Clinically, neutralizing antibodies with potent efficacy and high specificity have been extensively used to prevent and treat a wide variety of viral infections, including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), Human Immunodeficiency Virus (HIV), Dengue Virus (DENV) and Hepatitis B Virus (HBV). An overwhelmingly large subset of clinically effective NAbs operates by targeting viral envelope proteins to inhibit viral entry into the host cell. Binding of viral envelope protein to the host receptor is a critical rate limiting step triggering a cascade of downstream events, including endocytosis, membrane fusion and pore formation to allow viral entry. In recent years, improved structural knowledge on these processes have allowed researchers to also leverage NAbs as an indispensable tool in guiding discovery of novel antiviral entry inhibitors, providing drug candidates with high efficacy and pan-genus specificity. This review will summarize the latest progresses on the applications of NAbs as effective entry inhibitors and as important tools to develop antiviral therapeutics by high-throughput drug screenings, rational design of peptidic entry inhibitor mimicking NAbs and in silico computational modeling approaches.
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Affiliation(s)
- Ee Hong Tam
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore
| | - Yu Peng
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore
| | - Megan Xin Yan Cheah
- Institute of Molecular and Cell Biology, A*STAR (Agency of Science, Technology and Research) 138673, Singapore
| | - Chuan Yan
- Institute of Molecular and Cell Biology, A*STAR (Agency of Science, Technology and Research) 138673, Singapore
| | - Tianshu Xiao
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore.
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4
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Yu X, Hastie KM, Davis CW, Avalos RD, Williams D, Parekh D, Hui S, Mann C, Hariharan C, Takada A, Ahmed R, Saphire EO. The evolution and determinants of neutralization of potent head-binding antibodies against Ebola virus. Cell Rep 2023; 42:113366. [PMID: 37938974 PMCID: PMC11045044 DOI: 10.1016/j.celrep.2023.113366] [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: 05/01/2023] [Revised: 09/07/2023] [Accepted: 10/16/2023] [Indexed: 11/10/2023] Open
Abstract
Monoclonal antibodies against the Ebola virus (EBOV) surface glycoprotein are effective treatments for EBOV disease. Antibodies targeting the EBOV glycoprotein (GP) head epitope have potent neutralization and Fc effector function activity and thus are of high interest as therapeutics and for vaccine design. Here we focus on the head-binding antibodies 1A2 and 1D5, which have been identified previously in a longitudinal study of survivors of EBOV infection. 1A2 and 1D5 have the same heavy- and light-chain germlines despite being isolated from different individuals and at different time points after recovery from infection. Cryoelectron microscopy analysis of each antibody in complex with the EBOV surface GP reveals key amino acid substitutions in 1A2 that contribute to greater affinity, improved neutralization potency, and enhanced breadth as well as two strategies for antibody evolution from a common site.
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Affiliation(s)
- Xiaoying Yu
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Kathryn M Hastie
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Carl W Davis
- Emory Vaccine Center and Department of Microbiology and Immunology, Emory University, Atlanta, GA 30322, USA
| | - Ruben Diaz Avalos
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Dewight Williams
- Eyring Materials Center, Arizona State University, Tempe, AZ 85281, USA
| | - Diptiben Parekh
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Sean Hui
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Colin Mann
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Chitra Hariharan
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Ayato Takada
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
| | - Rafi Ahmed
- Emory Vaccine Center and Department of Microbiology and Immunology, Emory University, Atlanta, GA 30322, USA
| | - Erica Ollmann Saphire
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA 92037, USA; Department of Medicine, University of California, San Diego, San Diego, CA 92093, USA.
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5
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Rijal P, Donnellan FR. A review of broadly protective monoclonal antibodies to treat Ebola virus disease. Curr Opin Virol 2023; 61:101339. [PMID: 37392670 DOI: 10.1016/j.coviro.2023.101339] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 04/26/2023] [Accepted: 05/28/2023] [Indexed: 07/03/2023]
Abstract
The filovirus vaccine and the therapeutic monoclonal antibody (mAb) research have made substantial progress. However, existing vaccines and mAbs approved for use in humans are specific to Zaire ebolavirus (EBOV). Since other Ebolavirus species are a continuing threat to public health, the search for broadly protective mAbs has drawn attention. Here, we review viral glycoprotein-targeting mAbs that have proved their broader protective efficacy in animal models. MBP134AF, the most advanced of these new-generation mAb therapies, has recently been deployed in Uganda during the Sudan ebolavirus outbreak. Furthermore, we discuss the measures associated with enhancing antibody therapies and the risks associated with them, including the rise of escape mutations following the mAb treatment and naturally occurring EBOV variants.
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Affiliation(s)
- Pramila Rijal
- Center for Translational Immunology, Chinese Academy of Medical Science Oxford Institute, Nuffield Department of Medicine, University of Oxford, UK; MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, United Kingdom.
| | - Francesca R Donnellan
- Department of Biochemistry, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, United Kingdom; Kavli Institute for Nanoscience Discovery, University of Oxford, UK.
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6
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Kumar A, Rohe TC, Elrod EJ, Khan AG, Dearborn AD, Kissinger R, Grakoui A, Marcotrigiano J. Regions of hepatitis C virus E2 required for membrane association. Nat Commun 2023; 14:433. [PMID: 36702826 PMCID: PMC9879980 DOI: 10.1038/s41467-023-36183-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/19/2023] [Indexed: 01/27/2023] Open
Abstract
Hepatitis C virus (HCV) uses a hybrid entry mechanism. Current structural data suggest that upon exposure to low pH and Cluster of Differentiation 81 (CD81), the amino terminus of envelope glycoprotein E2 becomes ordered and releases an internal loop with two invariant aromatic residues into the host membrane. Here, we present the structure of an amino-terminally truncated E2 with the membrane binding loop in a bent conformation and the aromatic side chains sequestered. Comparison with three previously reported E2 structures with the same Fab indicates that this internal loop is flexible, and that local context influences the exposure of hydrophobic residues. Biochemical assays show that the amino-terminally truncated E2 lacks the baseline membrane-binding capacity of the E2 ectodomain. Thus, the amino terminal region is a critical determinant for both CD81 and membrane interaction. These results provide new insights into the HCV entry mechanism.
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Affiliation(s)
- Ashish Kumar
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Tiana C Rohe
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Elizabeth J Elrod
- Emory National Primate Research Center, Division of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, 30329, USA
| | - Abdul G Khan
- Center for Advanced Biotechnology and Medicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Altaira D Dearborn
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ryan Kissinger
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, 59840, USA
| | - Arash Grakoui
- Emory National Primate Research Center, Division of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, 30329, USA
| | - Joseph Marcotrigiano
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
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7
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Skin Vaccination with Ebola Virus Glycoprotein Using a Polyphosphazene-Based Microneedle Patch Protects Mice against Lethal Challenge. J Funct Biomater 2022; 14:jfb14010016. [PMID: 36662063 PMCID: PMC9860647 DOI: 10.3390/jfb14010016] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/23/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022] Open
Abstract
Ebolavirus (EBOV) infection in humans is a severe and often fatal disease, which demands effective interventional strategies for its prevention and treatment. The available vaccines, which are authorized under exceptional circumstances, use viral vector platforms and have serious disadvantages, such as difficulties in adapting to new virus variants, reliance on cold chain supply networks, and administration by hypodermic injection. Microneedle (MN) patches, which are made of an array of micron-scale, solid needles that painlessly penetrate into the upper layers of the skin and dissolve to deliver vaccines intradermally, simplify vaccination and can thereby increase vaccine access, especially in resource-constrained or emergency settings. The present study describes a novel MN technology, which combines EBOV glycoprotein (GP) antigen with a polyphosphazene-based immunoadjuvant and vaccine delivery system (poly[di(carboxylatophenoxy)phosphazene], PCPP). The protein-stabilizing effect of PCPP in the microfabrication process enabled preparation of a dissolvable EBOV GP MN patch vaccine with superior antigenicity compared to a non-polyphosphazene polymer-based analog. Intradermal immunization of mice with polyphosphazene-based MN patches induced strong, long-lasting antibody responses against EBOV GP, which was comparable to intramuscular injection. Moreover, mice vaccinated with the MN patches were completely protected against a lethal challenge using mouse-adapted EBOV and had no histologic lesions associated with ebolavirus disease.
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8
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Yu X, Saphire EO. Development and Structural Analysis of Antibody Therapeutics for Filoviruses. Pathogens 2022; 11:pathogens11030374. [PMID: 35335698 PMCID: PMC8949092 DOI: 10.3390/pathogens11030374] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 11/16/2022] Open
Abstract
The filoviruses, including ebolaviruses and marburgviruses, are among the world’s deadliest pathogens. As the only surface-exposed protein on mature virions, their glycoprotein GP is the focus of current therapeutic monoclonal antibody discovery efforts. With recent technological developments, potent antibodies have been identified from immunized animals and human survivors of virus infections and have been characterized functionally and structurally. Structural insight into how the most successful antibodies target GP further guides vaccine development. Here we review the recent developments in the identification and characterization of neutralizing antibodies and cocktail immunotherapies.
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Affiliation(s)
- Xiaoying Yu
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA;
| | - Erica Ollmann Saphire
- Center for Infectious Disease and Vaccine Discovery, La Jolla Institute for Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA;
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Correspondence: ; Tel.: +1-858-752-6791
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9
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Murin CD, Gilchuk P, Crowe JE, Ward AB. Structural Biology Illuminates Molecular Determinants of Broad Ebolavirus Neutralization by Human Antibodies for Pan-Ebolavirus Therapeutic Development. Front Immunol 2022; 12:808047. [PMID: 35082794 PMCID: PMC8784787 DOI: 10.3389/fimmu.2021.808047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/06/2021] [Indexed: 01/13/2023] Open
Abstract
Monoclonal antibodies (mAbs) have proven effective for the treatment of ebolavirus infection in humans, with two mAb-based drugs Inmazeb™ and Ebanga™ receiving FDA approval in 2020. While these drugs represent a major advance in the field of filoviral therapeutics, they are composed of antibodies with single-species specificity for Zaire ebolavirus. The Ebolavirus genus includes five additional species, two of which, Bundibugyo ebolavirus and Sudan ebolavirus, have caused severe disease and significant outbreaks in the past. There are several recently identified broadly neutralizing ebolavirus antibodies, including some in the clinical development pipeline, that have demonstrated broad protection in preclinical studies. In this review, we describe how structural biology has illuminated the molecular basis of broad ebolavirus neutralization, including details of common antigenic sites of vulnerability on the glycoprotein surface. We begin with a discussion outlining the history of monoclonal antibody therapeutics for ebolaviruses, with an emphasis on how structural biology has contributed to these efforts. Next, we highlight key structural studies that have advanced our understanding of ebolavirus glycoprotein structures and mechanisms of antibody-mediated neutralization. Finally, we offer examples of how structural biology has contributed to advances in anti-viral medicines and discuss what opportunities the future holds, including rationally designed next-generation therapeutics with increased potency, breadth, and specificity against ebolaviruses.
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MESH Headings
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized/immunology
- Antibodies, Monoclonal, Humanized/therapeutic use
- Antibodies, Neutralizing/immunology
- Antibodies, Viral/immunology
- Antiviral Agents/immunology
- Antiviral Agents/therapeutic use
- Drug Combinations
- Ebolavirus/drug effects
- Ebolavirus/immunology
- Ebolavirus/physiology
- Epitopes/chemistry
- Epitopes/immunology
- Glycoproteins/chemistry
- Glycoproteins/immunology
- Hemorrhagic Fever, Ebola/drug therapy
- Hemorrhagic Fever, Ebola/immunology
- Hemorrhagic Fever, Ebola/virology
- Humans
- Models, Molecular
- Protein Domains/immunology
- Viral Proteins/chemistry
- Viral Proteins/immunology
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Affiliation(s)
- Charles D. Murin
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States
| | - Pavlo Gilchuk
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
| | - James E. Crowe
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States
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10
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Hargreaves A, Brady C, Mellors J, Tipton T, Carroll MW, Longet S. Filovirus Neutralising Antibodies: Mechanisms of Action and Therapeutic Application. Pathogens 2021; 10:pathogens10091201. [PMID: 34578233 PMCID: PMC8468515 DOI: 10.3390/pathogens10091201] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 12/02/2022] Open
Abstract
Filoviruses, especially Ebola virus, cause sporadic outbreaks of viral haemorrhagic fever with very high case fatality rates in Africa. The 2013–2016 Ebola epidemic in West Africa provided large survivor cohorts spurring a large number of human studies which showed that specific neutralising antibodies played a key role in protection following a natural Ebola virus infection, as part of the overall humoral response and in conjunction with the cellular adaptive response. This review will discuss the studies in survivors and animal models which described protective neutralising antibody response. Their mechanisms of action will be detailed. Furthermore, the importance of neutralising antibodies in antibody-based therapeutics and in vaccine-induced responses will be explained, as well as the strategies to avoid immune escape from neutralising antibodies. Understanding the neutralising antibody response in the context of filoviruses is crucial to furthering our understanding of virus structure and function, in addition to improving current vaccines & antibody-based therapeutics.
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Affiliation(s)
- Alexander Hargreaves
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
- Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Caolann Brady
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
| | - Jack Mellors
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
- National Infection Service, Public Health England, Porton Down, Salisbury SP4 0JG, UK
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7ZX, UK
| | - Tom Tipton
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
| | - Miles W. Carroll
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
- National Infection Service, Public Health England, Porton Down, Salisbury SP4 0JG, UK
| | - Stephanie Longet
- Nuffield Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.H.); (C.B.); (J.M.); (T.T.); (M.W.C.)
- Correspondence: ; Tel.: +44-18-6561-7892
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11
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He L, Chaudhary A, Lin X, Sou C, Alkutkar T, Kumar S, Ngo T, Kosviner E, Ozorowski G, Stanfield RL, Ward AB, Wilson IA, Zhu J. Single-component multilayered self-assembling nanoparticles presenting rationally designed glycoprotein trimers as Ebola virus vaccines. Nat Commun 2021; 12:2633. [PMID: 33976149 DOI: 10.1101/2020.08.22.262634] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/06/2021] [Indexed: 05/27/2023] Open
Abstract
Ebola virus (EBOV) glycoprotein (GP) can be recognized by neutralizing antibodies (NAbs) and is the main target for vaccine design. Here, we first investigate the contribution of the stalk and heptad repeat 1-C (HR1C) regions to GP metastability. Specific stalk and HR1C modifications in a mucin-deleted form (GPΔmuc) increase trimer yield, whereas alterations of HR1C exert a more complex effect on thermostability. Crystal structures are determined to validate two rationally designed GPΔmuc trimers in their unliganded state. We then display a modified GPΔmuc trimer on reengineered protein nanoparticles that encapsulate a layer of locking domains (LD) and a cluster of helper T-cell epitopes. In mice and rabbits, GP trimers and nanoparticles elicit cross-ebolavirus NAbs, as well as non-NAbs that enhance pseudovirus infection. Repertoire sequencing reveals quantitative profiles of vaccine-induced B-cell responses. This study demonstrates a promising vaccine strategy for filoviruses, such as EBOV, based on GP stabilization and nanoparticle display.
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MESH Headings
- Animals
- Antibodies, Neutralizing/blood
- Antibodies, Neutralizing/immunology
- Antigens, Viral/administration & dosage
- Antigens, Viral/genetics
- Antigens, Viral/immunology
- Antigens, Viral/ultrastructure
- B-Lymphocytes/immunology
- Crystallography, X-Ray
- Disease Models, Animal
- Ebola Vaccines/administration & dosage
- Ebola Vaccines/genetics
- Ebola Vaccines/immunology
- Ebolavirus/genetics
- Ebolavirus/immunology
- Epitopes, T-Lymphocyte/administration & dosage
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/ultrastructure
- Female
- Glycoproteins/administration & dosage
- Glycoproteins/genetics
- Glycoproteins/immunology
- Glycoproteins/ultrastructure
- Hemorrhagic Fever, Ebola/blood
- Hemorrhagic Fever, Ebola/immunology
- Hemorrhagic Fever, Ebola/therapy
- Hemorrhagic Fever, Ebola/virology
- Humans
- Mice
- Nanoparticles/chemistry
- Protein Domains/genetics
- Protein Domains/immunology
- Protein Engineering
- Protein Multimerization/genetics
- Protein Multimerization/immunology
- Protein Stability
- Rabbits
- T-Lymphocytes, Helper-Inducer/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/genetics
- Vaccines, Subunit/immunology
- Viral Proteins/administration & dosage
- Viral Proteins/genetics
- Viral Proteins/immunology
- Viral Proteins/ultrastructure
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Affiliation(s)
- Linling He
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Anshul Chaudhary
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Xiaohe Lin
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Cindy Sou
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Tanwee Alkutkar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sonu Kumar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Timothy Ngo
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ezra Kosviner
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Robyn L Stanfield
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA.
- Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA.
| | - Jiang Zhu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA.
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
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12
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He L, Chaudhary A, Lin X, Sou C, Alkutkar T, Kumar S, Ngo T, Kosviner E, Ozorowski G, Stanfield RL, Ward AB, Wilson IA, Zhu J. Single-component multilayered self-assembling nanoparticles presenting rationally designed glycoprotein trimers as Ebola virus vaccines. Nat Commun 2021; 12:2633. [PMID: 33976149 PMCID: PMC8113551 DOI: 10.1038/s41467-021-22867-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/06/2021] [Indexed: 12/17/2022] Open
Abstract
Ebola virus (EBOV) glycoprotein (GP) can be recognized by neutralizing antibodies (NAbs) and is the main target for vaccine design. Here, we first investigate the contribution of the stalk and heptad repeat 1-C (HR1C) regions to GP metastability. Specific stalk and HR1C modifications in a mucin-deleted form (GPΔmuc) increase trimer yield, whereas alterations of HR1C exert a more complex effect on thermostability. Crystal structures are determined to validate two rationally designed GPΔmuc trimers in their unliganded state. We then display a modified GPΔmuc trimer on reengineered protein nanoparticles that encapsulate a layer of locking domains (LD) and a cluster of helper T-cell epitopes. In mice and rabbits, GP trimers and nanoparticles elicit cross-ebolavirus NAbs, as well as non-NAbs that enhance pseudovirus infection. Repertoire sequencing reveals quantitative profiles of vaccine-induced B-cell responses. This study demonstrates a promising vaccine strategy for filoviruses, such as EBOV, based on GP stabilization and nanoparticle display. Ebola virus glycoprotein (GP) is a major target for vaccine design. Here, the authors identify mutations to improve GP stability and yield, design two multilayered nanoparticle carriers, and demonstrate good immunogenicity of the modified GP on nanoparticles in mice and rabbits.
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Affiliation(s)
- Linling He
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Anshul Chaudhary
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Xiaohe Lin
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Cindy Sou
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Tanwee Alkutkar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sonu Kumar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Timothy Ngo
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ezra Kosviner
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Robyn L Stanfield
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA. .,Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA.
| | - Jiang Zhu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA. .,Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
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13
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Rutten L, Gilman MSA, Blokland S, Juraszek J, McLellan JS, Langedijk JPM. Structure-Based Design of Prefusion-Stabilized Filovirus Glycoprotein Trimers. Cell Rep 2021; 30:4540-4550.e3. [PMID: 32234486 PMCID: PMC7118701 DOI: 10.1016/j.celrep.2020.03.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 01/27/2020] [Accepted: 03/10/2020] [Indexed: 12/16/2022] Open
Abstract
Ebola virus causes severe hemorrhagic fever, often leading to death in humans. The trimeric fusion glycoprotein (GP) is the sole target for neutralizing antibodies and is the major focus of vaccine development. Soluble GP ectodomains are unstable and mostly monomeric when not fused to a heterologous trimerization domain. Here, we report structure-based designs of Ebola and Marburg GP trimers based on a stabilizing mutation in the hinge loop in refolding region 1 and substitution of a partially buried charge at the interface of the GP1 and GP2 subunits. The combined substitutions (T577P and K588F) substantially increased trimer expression for Ebola GP proteins. We determined the crystal structure of stabilized GP from the Makona Zaire ebolavirus strain without a trimerization domain or complexed ligand. The structure reveals that the stabilized GP adopts the same trimeric prefusion conformation, provides insight into triggering of GP conformational changes, and should inform future filovirus vaccine development. Filovirus GP expression increases by stabilizing mutations in hinge loop and base helix Charged lysine in base helix and GP1 N terminus are trapped in metastable conformation Crystal structure of stabilized Makona Δmucin GP confirms successful stabilization These findings may be useful for understanding fusion mechanisms and vaccine design
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Affiliation(s)
- Lucy Rutten
- Janssen Vaccines & Prevention, Archimedesweg 4-6, Leiden 2333 CN, the Netherlands
| | - Morgan S A Gilman
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Sven Blokland
- Janssen Vaccines & Prevention, Archimedesweg 4-6, Leiden 2333 CN, the Netherlands
| | - Jarek Juraszek
- Janssen Vaccines & Prevention, Archimedesweg 4-6, Leiden 2333 CN, the Netherlands
| | - Jason S McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA.
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14
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Ripoll DR, Chaudhury S, Wallqvist A. Using the antibody-antigen binding interface to train image-based deep neural networks for antibody-epitope classification. PLoS Comput Biol 2021; 17:e1008864. [PMID: 33780441 PMCID: PMC8032195 DOI: 10.1371/journal.pcbi.1008864] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 04/08/2021] [Accepted: 03/10/2021] [Indexed: 12/05/2022] Open
Abstract
High-throughput B-cell sequencing has opened up new avenues for investigating complex mechanisms underlying our adaptive immune response. These technological advances drive data generation and the need to mine and analyze the information contained in these large datasets, in particular the identification of therapeutic antibodies (Abs) or those associated with disease exposure and protection. Here, we describe our efforts to use artificial intelligence (AI)-based image-analyses for prospective classification of Abs based solely on sequence information. We hypothesized that Abs recognizing the same part of an antigen share a limited set of features at the binding interface, and that the binding site regions of these Abs share share common structure and physicochemical property patterns that can serve as a "fingerprint" to recognize uncharacterized Abs. We combined large-scale sequence-based protein-structure predictions to generate ensembles of 3-D Ab models, reduced the Ab binding interface to a 2-D image (fingerprint), used pre-trained convolutional neural networks to extract features, and trained deep neural networks (DNNs) to classify Abs. We evaluated this approach using Ab sequences derived from human HIV and Ebola viral infections to differentiate between two Abs, Abs belonging to specific B-cell family lineages, and Abs with different epitope preferences. In addition, we explored a different type of DNN method to detect one class of Abs from a larger pool of Abs. Testing on Ab sets that had been kept aside during model training, we achieved average prediction accuracies ranging from 71-96% depending on the complexity of the classification task. The high level of accuracies reached during these classification tests suggests that the DNN models were able to learn a series of structural patterns shared by Abs belonging to the same class. The developed methodology provides a means to apply AI-based image recognition techniques to analyze high-throughput B-cell sequencing datasets (repertoires) for Ab classification.
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Affiliation(s)
- Daniel R. Ripoll
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Sidhartha Chaudhury
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, Maryland, United States of America
- Center for Enabling Capabilities, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Anders Wallqvist
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, Maryland, United States of America
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15
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Misasi J, Sullivan NJ. Immunotherapeutic strategies to target vulnerabilities in the Ebolavirus glycoprotein. Immunity 2021; 54:412-436. [PMID: 33691133 DOI: 10.1016/j.immuni.2021.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 01/15/2021] [Accepted: 01/20/2021] [Indexed: 12/18/2022]
Abstract
The 2014 Ebola virus disease (EVD) outbreak in West Africa and the subsequent outbreaks of 2018-2020 in Equator and North Kivu provinces of the Democratic Republic of the Congo illustrate the public health challenges of emerging and reemerging viruses. EVD has a high case fatality rate with a rapidly progressing syndrome of fever, rash, vomiting, diarrhea, and bleeding diathesis. Recently, two monoclonal-antibody-based therapies received United States Food and Drug Administration (FDA) approval, and there are several other passive immunotherapies that hold promise as therapeutics against other species of Ebolavirus. Here, we review concepts needed to understand mechanisms of action, present an expanded schema to define additional sites of vulnerability on the viral glycoprotein, and review current antibody-based therapeutics. The concepts described are used to gain insights into the key characteristics that represent functional targets for immunotherapies against Zaire Ebolavirus and other emerging viruses within the Ebolavirus genus.
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Affiliation(s)
- John Misasi
- National Institutes of Health, National Institute of Allergy and Infectious Diseases, Vaccine Research Center, 40 Convent Drive, Bethesda, MD 20892, USA
| | - Nancy J Sullivan
- National Institutes of Health, National Institute of Allergy and Infectious Diseases, Vaccine Research Center, 40 Convent Drive, Bethesda, MD 20892, USA.
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16
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Atypical Ebola Virus Disease in a Nonhuman Primate following Monoclonal Antibody Treatment Is Associated with Glycoprotein Mutations within the Fusion Loop. mBio 2021; 12:mBio.01438-20. [PMID: 33436428 PMCID: PMC7844533 DOI: 10.1128/mbio.01438-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Ebola virus remains a global threat to public health and biosecurity, yet we still know relatively little about its pathogenesis and the complications that arise following recovery. With nearly 20,000 survivors from the 2013–2016 West African outbreak, as well as over 1,000 survivors of the recent outbreak in the DRC, we must consider the consequences of virus persistence and recrudescent disease, even if they are rare. Ebola virus (EBOV) is responsible for numerous devastating outbreaks throughout Africa, including the 2013–2016 West African outbreak as well as the two recent outbreaks in the Democratic Republic of the Congo (DRC), one of which is ongoing. Although EBOV disease (EVD) has typically been considered a highly lethal acute infection, increasing evidence suggests that the virus can persist in certain immune-privileged sites and occasionally lead to EVD recrudescence. Little is understood about the processes that contribute to EBOV persistence and recrudescence, in part because of the rarity of these phenomena but also because of the absence of an animal model that recapitulates them. Here, we describe a case of EBOV persistence associated with atypical EVD in a nonhuman primate (NHP) following inoculation with EBOV and treatment with an experimental monoclonal antibody cocktail. Although this animal exhibited only mild signs of acute EVD, it developed severe disease 2 weeks later and succumbed shortly thereafter. Viremia was undetectable at the time of death, despite abundant levels of viral RNA in most tissues, each of which appeared to harbor a distinct viral quasispecies. Remarkably, sequence analysis identified a single mutation in glycoprotein (GP) that not only resisted antibody-mediated neutralization but also increased viral growth kinetics and virulence. Overall, this report represents the most thoroughly characterized case of atypical EVD in an NHP described thus far, and it provides valuable insight into factors that may contribute to EBOV persistence and recrudescent disease.
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17
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Agnolon V, Kiseljak D, Wurm MJ, Wurm FM, Foissard C, Gallais F, Wehrle S, Muñoz-Fontela C, Bellanger L, Correia BE, Corradin G, Spertini F. Designs and Characterization of Subunit Ebola GP Vaccine Candidates: Implications for Immunogenicity. Front Immunol 2020; 11:586595. [PMID: 33250896 PMCID: PMC7672190 DOI: 10.3389/fimmu.2020.586595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/13/2020] [Indexed: 11/13/2022] Open
Abstract
The humoral responses of Ebola virus (EBOV) survivors mainly target the surface glycoprotein GP, and anti-GP neutralizing antibodies have been associated with protection against EBOV infection. In order to elicit protective neutralizing antibodies through vaccination a native-like conformation of the antigen is required. We therefore engineered and expressed in CHO cells several GP variants from EBOV (species Zaire ebolavirus, Mayinga variant), including a soluble GP ΔTM, a mucin-like domain-deleted GP ΔTM-ΔMUC, as well as two GP ΔTM-ΔMUC variants with C-terminal trimerization motifs in order to favor their native trimeric conformation. Inclusion of the trimerization motifs resulted in proteins mimicking GP metastable trimer and showing increased stability. The mucin-like domain appeared not to be critical for the retention of the native conformation of the GP protein, and its removal unmasked several neutralizing epitopes, especially in the trimers. The soluble GP variants inhibited mAbs neutralizing activity in a pseudotype transduction assay, further confirming the proteins' structural integrity. Interestingly, the trimeric GPs, a native-like GP complex, showed stronger affinity for antibodies raised by natural infection in EBOV disease survivors rather than for antibodies raised in volunteers that received the ChAd3-EBOZ vaccine. These results support our hypothesis that neutralizing antibodies are preferentially induced when using a native-like conformation of the GP antigen. The soluble trimeric recombinant GP proteins we developed represent a novel and promising strategy to develop prophylactic vaccines against EBOV and other filoviruses.
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Affiliation(s)
- Valentina Agnolon
- Division of Immunology and Allergy, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | | | | | - Florian M Wurm
- ExcellGene SA, Monthey, Switzerland.,Faculty of Life Sciences, École Polytechnique Fédérale De Lausanne (EPFL), Lausanne, Switzerland
| | - Charlotte Foissard
- Université Paris Saclay, Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Département Médicaments et Technologies pour la Santé (DMTS), SPI, Bagnols-sur-Cèze, France
| | - Fabrice Gallais
- Université Paris Saclay, Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Département Médicaments et Technologies pour la Santé (DMTS), SPI, Bagnols-sur-Cèze, France
| | - Sarah Wehrle
- Laboratory of Protein Design and Immunoengineering, École Polytechnique Fédérale De Lausanne (EPFL), Lausanne, Switzerland
| | - César Muñoz-Fontela
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research (DZIF), Partner site Hamburg, Hamburg, Germany
| | - Laurent Bellanger
- Université Paris Saclay, Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Département Médicaments et Technologies pour la Santé (DMTS), SPI, Bagnols-sur-Cèze, France
| | - Bruno Emanuel Correia
- Laboratory of Protein Design and Immunoengineering, École Polytechnique Fédérale De Lausanne (EPFL), Lausanne, Switzerland
| | - Giampietro Corradin
- Department of Biochemistry, Université de Lausanne (UNIL), Epalinges, Switzerland
| | - François Spertini
- Division of Immunology and Allergy, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
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18
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Pereira-Gomez M, Lopez-Tort F, Fajardo A, Cristina J. An evolutionary insight into emerging Ebolavirus strains isolated in Africa. J Med Virol 2019; 92:988-995. [PMID: 31702053 DOI: 10.1002/jmv.25627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 11/04/2019] [Indexed: 11/11/2022]
Abstract
On July 19, 2019, the World Health Organization declared the current Ebolavirus (EBOV) outbreak in Congo Democratic Republic (COD) a public health emergency of international concern. To address the potential threat of EBOV evolution outpacing antibody treatment and vaccine efforts, a detailed evolutionary analysis of EBOV strains circulating in different African countries was performed. Genome composition of EBOV strains was studied using multivariate statistical analysis. To investigate the patterns of evolution of EBOV strains, a Bayesian Markov Chain Monte Carlo approach was used. Two different genetic lineages, with a distinct genome composition gave rise to the recent EBOV outbreaks in central and western Africa. Strains isolated in COD in 2018 fall into two different genetic clusters, according to their geographical location of isolation. Different amino acid substitutions among strains from these two clusters have been found, particularly in NP, GP, and L proteins. Significant differences in codon and amino acid usage among clusters were found. Strains isolated in COD in 2018 belong to two distinct genetic clusters, with distinct codon and amino acid usage. Geographical diversity plays an important role in shaping the molecular evolution of EBOV populations.
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Affiliation(s)
- Marianoel Pereira-Gomez
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.,Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Fernando Lopez-Tort
- Laboratorio de Virología Molecular, Sede Salto, Centro Universitario Regional Litoral Norte, Universidad de la República, Salto, Uruguay
| | - Alvaro Fajardo
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Juan Cristina
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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19
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Therapeutic strategies to target the Ebola virus life cycle. Nat Rev Microbiol 2019; 17:593-606. [DOI: 10.1038/s41579-019-0233-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2019] [Indexed: 02/07/2023]
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20
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Xu Z, Kulp DW. Protein engineering and particulate display of B-cell epitopes to facilitate development of novel vaccines. Curr Opin Immunol 2019; 59:49-56. [PMID: 31029909 DOI: 10.1016/j.coi.2019.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/08/2019] [Accepted: 03/18/2019] [Indexed: 12/11/2022]
Abstract
Induction of antigen-specific humoral immunity is a correlate of protection for many diseases and remains a primary vaccine goal. Pathogens can evade such responses by limiting epitope access, by diversifying surface residues, or by keeping antigens in metastable conformations. B cells can target diverse epitopes on an antigen, but only a subset of which produce functional antibodies. Structure-based immunogen engineering can help overcome these hurdles by using structural information for targeted induction of particular antibodies while improving the overall vaccine immunogenicity. This review will cover recent progress in vaccine design, specifically focusing on strategies to stabilize antigens for optimal B-cell epitope exposure, engineer synthetic B-cell epitopes to induce antibodies with specific features and enhancement of vaccine potency through antigen presentation on multivalent particles.
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Affiliation(s)
- Ziyang Xu
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA 19104, United States; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States
| | - Daniel W Kulp
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA 19104, United States.
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21
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Expanding the watch list for potential Ebola virus antibody escape mutations. PLoS One 2019; 14:e0211093. [PMID: 30897171 PMCID: PMC6428255 DOI: 10.1371/journal.pone.0211093] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/06/2019] [Indexed: 12/28/2022] Open
Abstract
The 2014 outbreak of Ebola virus disease (EVD) in Western Africa is the largest recorded filovirus disease outbreak and led to the death of over 11,000 people. The recent EVD outbreaks (since May 2018) in the Democratic Republic of the Congo has already claimed the lives of over 250 people. Tackling Ebola virus (EBOV) outbreaks remains a challenge. Over the years, significant efforts have been put into developing vaccines or antibody therapies which rely on an envelope glycoprotein (GP) of Zaire ebolavirus (strain Mayinga-76). Therefore, one key approach for combating EVD epidemics is to predict mutations that may diminish the effectiveness of the treatment. In a previous study we generated a watch list of potential antibody escape mutations of EBOV GP against the monoclonal antibody KZ52. Molecular modeling methods were applied to the three-dimensional experimental structure of EBOV GP bound to KZ52 to predict the effect of every possible single mutation in EBOV GP. The final watch list contained 34 mutations that were predicted to destabilize binding of KZ52 to EBOV GP but did not affect EBOV GP folding and its ability to form trimers. In this study, we expand our watch list by including three more monoclonal antibodies with distinct epitopes on GP, namely Antibody 100 (Ab100), Antibody 114 (Ab114) and 13F6-1-2. Our updated watch list contains 127 mutations, three of which have been seen in humans or are experimentally associated with reduced efficacy of antibody treatment. We believe mutations on this watch list require attention since they provide information about circumstances in which interventions could lose the effectiveness.
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22
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King LB, Milligan JC, West BR, Schendel SL, Ollmann Saphire E. Achieving cross-reactivity with pan-ebolavirus antibodies. Curr Opin Virol 2019; 34:140-148. [PMID: 30884329 DOI: 10.1016/j.coviro.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/24/2019] [Indexed: 11/25/2022]
Abstract
Filoviruses are the causative agents of highly lethal outbreaks in sub-Saharan Africa. Although an experimental vaccine and several therapeutics are being deployed in the Democratic Republic of Congo to combat the ongoing Ebola virus outbreak, these therapies are specific for only one filovirus species. There is currently significant interest in developing broadly reactive monoclonal antibodies (mAbs) with utility against the variety of ebolaviruses that may emerge. Thus far, the primary target of these mAbs has been the viral spike glycoprotein (GP). Here we present an overview of GP-targeted antibodies that exhibit broad reactivity and the structural characteristics that could confer this cross-reactivity. We also discuss how these structural features could be leveraged to design vaccine antigens that elicit cross-reactive antibodies.
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Affiliation(s)
- Liam B King
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jacob C Milligan
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Brandyn R West
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Sharon L Schendel
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Erica Ollmann Saphire
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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