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Gorzkiewicz M, Cramer J, Xu HC, Lang PA. The role of glycosylation patterns of viral glycoproteins and cell entry receptors in arenavirus infection. Biomed Pharmacother 2023; 166:115196. [PMID: 37586116 DOI: 10.1016/j.biopha.2023.115196] [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: 05/22/2023] [Revised: 07/14/2023] [Accepted: 07/18/2023] [Indexed: 08/18/2023] Open
Abstract
Mammarenaviruses are enveloped RNA viruses that can be associated with rodent-transmitted diseases in humans. Their virions are composed of a nucleocapsid surrounded by a lipid bilayer with glycoprotein (GP) spikes interacting with receptors on target cells. Both the GP and receptors are highly glycosylated, with glycosylation patterns being crucial for virus binding and cell entry, viral tropism, immune responses, or therapy strategies. These effects have been previously described for several different viruses. In case of arenaviruses, they remain insufficiently understood. Thus, it is important to determine the mechanisms of glycosylation of viral proteins and receptors responsible for infection, in order to fully understand the biology of arenaviruses. In this article, we have summarized and critically evaluated the available literature data on the glycosylation of mammarenavirus-associated proteins to facilitate further research in this field.
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Affiliation(s)
- Michal Gorzkiewicz
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany; Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, 141/143 Pomorska St., 90-236 Lodz, Poland.
| | - Jonathan Cramer
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Haifeng C Xu
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Philipp A Lang
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
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VelcroVax: a "Bolt-On" Vaccine Platform for Glycoprotein Display. mSphere 2023; 8:e0056822. [PMID: 36719225 PMCID: PMC9942589 DOI: 10.1128/msphere.00568-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Having varied approaches to the design and manufacture of vaccines is critical in being able to respond to worldwide needs and newly emerging pathogens. Virus-like particles (VLPs) form the basis of two of the most successful licensed vaccines (against hepatitis B virus [HBV] and human papillomavirus). They are produced by recombinant expression of viral structural proteins, which assemble into immunogenic nanoparticles. VLPs can be modified to present unrelated antigens, and here we describe a universal "bolt-on" platform (termed VelcroVax) where the capturing VLP and the target antigen are produced separately. We utilize a modified HBV core (HBcAg) VLP with surface expression of a high-affinity binding sequence (Affimer) directed against a SUMO tag and use this to capture SUMO-tagged gp1 glycoprotein from the arenavirus Junín virus (JUNV). Using this model system, we have solved the first high-resolution structures of VelcroVax VLPs and shown that the VelcroVax-JUNV gp1 complex induces superior humoral immune responses compared to the noncomplexed viral protein. We propose that this system could be modified to present a range of antigens and therefore form the foundation of future rapid-response vaccination strategies. IMPORTANCE The hepatitis B core protein (HBc) forms noninfectious virus-like particles, which can be modified to present a capturing molecule, allowing suitably tagged antigens to be bound on their surface. This system can be adapted and provides the foundation for a universal "bolt-on" vaccine platform (termed VelcroVax) that can be easily and rapidly modified to generate nanoparticle vaccine candidates.
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Ng WM, Sahin M, Krumm SA, Seow J, Zeltina A, Harlos K, Paesen GC, Pinschewer DD, Doores KJ, Bowden TA. Contrasting Modes of New World Arenavirus Neutralization by Immunization-Elicited Monoclonal Antibodies. mBio 2022; 13:e0265021. [PMID: 35315691 PMCID: PMC9040744 DOI: 10.1128/mbio.02650-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 01/28/2022] [Indexed: 12/31/2022] Open
Abstract
Transmission of the New World hemorrhagic fever arenaviruses Junín virus (JUNV) and Machupo virus (MACV) to humans is facilitated, in part, by the interaction between the arenavirus GP1 glycoprotein and the human transferrin receptor 1 (hTfR1). We utilize a mouse model of live-attenuated immunization with envelope exchange viruses to isolate neutralizing monoclonal antibodies (NAbs) specific to JUNV GP1 and MACV GP1. Structures of two NAbs, termed JUN1 and MAC1, demonstrate that they neutralize through disruption of hTfR1 recognition. JUN1 utilizes a binding mode common to all characterized infection- and vaccine-elicited JUNV-specific NAbs, which involves mimicking hTfR1 binding through the insertion of a tyrosine into the receptor-binding site. In contrast, MAC1 undergoes a tyrosine-mediated mode of antigen recognition distinct from that used by the reported anti-JUNV NAbs and the only other characterized anti-MACV NAb. These data reveal the varied modes of GP1-specific recognition among New World arenaviruses by the antibody-mediated immune response. IMPORTANCE The GP1 subcomponent of the New World arenavirus GP is a primary target of the neutralizing antibody response, which has been shown to be effective in the prevention and treatment of infection. Here, we characterize the structural basis of the antibody-mediated immune response that arises from immunization of mice against Junín virus and Machupo virus, two rodent-borne zoonotic New World arenaviruses. We isolate a panel of GP1-specific monoclonal antibodies that recognize overlapping epitopes and exhibit neutralizing behavior, in vitro. Structural characterization of two of these antibodies indicates that antibody recognition likely interferes with GP1-mediated recognition of the transferrin receptor 1. These data provide molecular-level detail for a key region of vulnerability on the New World arenavirus surface and a blueprint for therapeutic antibody development.
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Affiliation(s)
- Weng M. Ng
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Mehmet Sahin
- Department of Biomedicine, Division of Experimental Virology, University of Basel, Basel, Switzerland
| | - Stefanie A. Krumm
- Kings College London, Department of Infectious Diseases, Guy’s Hospital, London, United Kingdom
| | - Jeffrey Seow
- Kings College London, Department of Infectious Diseases, Guy’s Hospital, London, United Kingdom
| | - Antra Zeltina
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Karl Harlos
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Guido C. Paesen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Daniel D. Pinschewer
- Department of Biomedicine, Division of Experimental Virology, University of Basel, Basel, Switzerland
| | - Katie J. Doores
- Kings College London, Department of Infectious Diseases, Guy’s Hospital, London, United Kingdom
| | - Thomas A. Bowden
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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The late endosome-resident lipid bis(monoacylglycero)phosphate is a cofactor for Lassa virus fusion. PLoS Pathog 2021; 17:e1009488. [PMID: 34492091 PMCID: PMC8448326 DOI: 10.1371/journal.ppat.1009488] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 09/17/2021] [Accepted: 08/25/2021] [Indexed: 11/20/2022] Open
Abstract
Arenavirus entry into host cells occurs through a low pH-dependent fusion with late endosomes that is mediated by the viral glycoprotein complex (GPC). The mechanisms of GPC-mediated membrane fusion and of virus targeting to late endosomes are not well understood. To gain insights into arenavirus fusion, we examined cell-cell fusion induced by the Old World Lassa virus (LASV) GPC complex. LASV GPC-mediated cell fusion is more efficient and occurs at higher pH with target cells expressing human LAMP1 compared to cells lacking this cognate receptor. However, human LAMP1 is not absolutely required for cell-cell fusion or LASV entry. We found that GPC-induced fusion progresses through the same lipid intermediates as fusion mediated by other viral glycoproteins–a lipid curvature-sensitive intermediate upstream of hemifusion and a hemifusion intermediate downstream of acid-dependent steps that can be arrested in the cold. Importantly, GPC-mediated fusion and LASV pseudovirus entry are specifically augmented by an anionic lipid, bis(monoacylglycero)phosphate (BMP), which is highly enriched in late endosomes. This lipid also specifically promotes cell fusion mediated by Junin virus GPC, an unrelated New World arenavirus. We show that BMP promotes late steps of LASV fusion downstream of hemifusion–the formation and enlargement of fusion pores. The BMP-dependence of post-hemifusion stages of arenavirus fusion suggests that these viruses evolved to use this lipid as a cofactor to selectively fuse with late endosomes. Pathogenic arenaviruses pose a serious health threat. The viral envelope glycoprotein GPC mediates attachment to host cells and drives virus entry via endocytosis and low pH-dependent fusion within late endosomes. Understanding the host factors and processes that are essential for arenavirus fusion may identify novel therapeutic targets. To delineate the mechanism of arenavirus entry, we examined cell-cell fusion induced by the Old World Lassa virus GPC proteins at low pH. Lassa GPC-mediated fusion was augmented by the human LAMP1 receptor and progressed through lipid curvature-sensitive intermediates, such as hemifusion (merger of contacting leaflets of viral and cell membrane without the formation of a fusion pore). We found that most GPC-mediated fusion events were off-path hemifusion structures and that the transition from hemifusion to full fusion and fusion pore enlargement were specifically promoted by an anionic lipid, bis(monoacylglycero)phosphate, which is highly enriched in late endosomes. This lipid also specifically promotes fusion of unrelated New World Junin arenavirus. Our results imply that arenaviruses evolved to use bis(monoacylglycero)phosphate to enter cells from late endosomes.
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Hulswit RJG, Paesen GC, Bowden TA, Shi X. Recent Advances in Bunyavirus Glycoprotein Research: Precursor Processing, Receptor Binding and Structure. Viruses 2021; 13:353. [PMID: 33672327 PMCID: PMC7926653 DOI: 10.3390/v13020353] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/13/2021] [Accepted: 02/15/2021] [Indexed: 01/04/2023] Open
Abstract
The Bunyavirales order accommodates related viruses (bunyaviruses) with segmented, linear, single-stranded, negative- or ambi-sense RNA genomes. Their glycoproteins form capsomeric projections or spikes on the virion surface and play a crucial role in virus entry, assembly, morphogenesis. Bunyavirus glycoproteins are encoded by a single RNA segment as a polyprotein precursor that is co- and post-translationally cleaved by host cell enzymes to yield two mature glycoproteins, Gn and Gc (or GP1 and GP2 in arenaviruses). These glycoproteins undergo extensive N-linked glycosylation and despite their cleavage, remain associated to the virion to form an integral transmembrane glycoprotein complex. This review summarizes recent advances in our understanding of the molecular biology of bunyavirus glycoproteins, including their processing, structure, and known interactions with host factors that facilitate cell entry.
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Affiliation(s)
- Ruben J. G. Hulswit
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Guido C. Paesen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Thomas A. Bowden
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Xiaohong Shi
- MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G61 1QH, UK
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Re S, Mizuguchi K. Glycan Cluster Shielding and Antibody Epitopes on Lassa Virus Envelop Protein. J Phys Chem B 2021; 125:2089-2097. [PMID: 33606939 DOI: 10.1021/acs.jpcb.0c11516] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
An understanding of how an antiviral monoclonal antibody recognizes its target is vital for the development of neutralizing antibodies and vaccines. The extensive glycosylation of viral proteins almost certainly affects the antibody response, but the investigation of such effects is hampered by the huge range of structures and interactions of surface glycans through their inherent complexity and flexibility. Here, we built an atomistic model of a fully glycosylated envelope protein complex of the Lassa virus and performed molecular dynamics simulations to characterize the impact of surface glycans on the antibody response. The simulations attested to the variety of conformations and interactions of surface glycans. The results show that glycosylation nonuniformly shields the surface of the complex and only marginally affects protein dynamics. The glycans gather in distinct clusters through interaction with protein residues, and only a few regions are left accessible by an antibody. We successfully recovered known protein epitopes by integrating the simulation results with existing sequence- and structure-based epitope prediction methods. The results emphasize the rich structural environment of glycans and demonstrate that shielding is not merely envelopment by a uniform blanket of sugars. This work provides a molecular basis for integrating otherwise elusive structural properties of glycans into vaccine and neutralizing antibody developments.
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Affiliation(s)
- Suyong Re
- Center for Drug Design Research, National Institutes of Biomedical Innovation, Health, and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan.,RIKEN Center for Biosystems Dynamics Research, Integrated Innovation Building 7F, 6-7-1 minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Kenji Mizuguchi
- Center for Drug Design Research, National Institutes of Biomedical Innovation, Health, and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan.,Artificial Intelligence Center for Health and Biomedical Research, National Institutes of Biomedical Innovation, Health, and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan.,Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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Ng WM, Stelfox AJ, Bowden TA. Unraveling virus relationships by structure-based phylogenetic classification. Virus Evol 2020; 6:veaa003. [PMID: 32064119 PMCID: PMC7015158 DOI: 10.1093/ve/veaa003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Delineation of the intricacies of protein function from macromolecular structure constitutes a continual obstacle in the study of cell and pathogen biology. Structure-based phylogenetic analysis has emerged as a powerful tool for addressing this challenge, allowing the detection and quantification of conserved architectural properties between proteins, including those with low or no detectable sequence homology. With a focus on viral protein structure, we highlight how a number of investigations have utilized this powerful method to infer common functionality and ancestry.
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Affiliation(s)
- Weng M Ng
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Alice J Stelfox
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Thomas A Bowden
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
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Structure-Based Classification Defines the Discrete Conformational Classes Adopted by the Arenaviral GP1. J Virol 2018; 93:JVI.01048-18. [PMID: 30305351 PMCID: PMC6288339 DOI: 10.1128/jvi.01048-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 09/28/2018] [Indexed: 02/08/2023] Open
Abstract
The genetically and geographically diverse group of viruses within the family Arenaviridae includes a number of zoonotic pathogens capable of causing fatal hemorrhagic fever. The multisubunit GPC glycoprotein spike complex displayed on the arenavirus envelope is a key determinant of species tropism and a primary target of the host humoral immune response. Here, we show that the receptor-binding GP1 subcomponent of the GPC spike from Old World but not New World arenaviruses adopts a distinct, pH-independent conformation in the absence of the cognate GP2. Our analysis provides a structure-based approach to understanding the discrete conformational classes sampled by these therapeutically important targets, informing strategies to develop arenaviral glycoprotein immunogens that resemble GPC as presented on the mature virion surface. The emergence of Old and New World arenaviruses from rodent reservoirs persistently threatens human health. The GP1 subunit of the envelope-displayed arenaviral glycoprotein spike complex (GPC) mediates host cell recognition and is an important determinant of cross-species transmission. Previous structural analyses of Old World arenaviral GP1 glycoproteins, alone and in complex with a cognate GP2 subunit, have revealed that GP1 adopts two distinct conformational states distinguished by differences in the orientations of helical regions of the molecule. Here, through comparative study of the GP1 glycoprotein architectures of Old World Loei River virus and New World Whitewater Arroyo virus, we show that these rearrangements are restricted to Old World arenaviruses and are not induced solely by the pH change that is associated with virus endosomal trafficking. Our structure-based phylogenetic analysis of arenaviral GP1s provides a blueprint for understanding the discrete structural classes adopted by these therapeutically important targets. IMPORTANCE The genetically and geographically diverse group of viruses within the family Arenaviridae includes a number of zoonotic pathogens capable of causing fatal hemorrhagic fever. The multisubunit GPC glycoprotein spike complex displayed on the arenavirus envelope is a key determinant of species tropism and a primary target of the host humoral immune response. Here, we show that the receptor-binding GP1 subcomponent of the GPC spike from Old World but not New World arenaviruses adopts a distinct, pH-independent conformation in the absence of the cognate GP2. Our analysis provides a structure-based approach to understanding the discrete conformational classes sampled by these therapeutically important targets, informing strategies to develop arenaviral glycoprotein immunogens that resemble GPC as presented on the mature virion surface.
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Watanabe Y, Raghwani J, Allen JD, Seabright GE, Li S, Moser F, Huiskonen JT, Strecker T, Bowden TA, Crispin M. Structure of the Lassa virus glycan shield provides a model for immunological resistance. Proc Natl Acad Sci U S A 2018; 115:7320-7325. [PMID: 29941589 PMCID: PMC6048489 DOI: 10.1073/pnas.1803990115] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Lassa virus is an Old World arenavirus endemic to West Africa that causes severe hemorrhagic fever. Vaccine development has focused on the envelope glycoprotein complex (GPC) that extends from the virion envelope. The often inadequate antibody immune response elicited by both vaccine and natural infection has been, in part, attributed to the abundance of N-linked glycosylation on the GPC. Here, using a virus-like-particle system that presents Lassa virus GPC in a native-like context, we determine the composite population of each of the N-linked glycosylation sites presented on the trimeric GPC spike. Our analysis reveals the presence of underprocessed oligomannose-type glycans, which form punctuated clusters that obscure the proteinous surface of both the GP1 attachment and GP2 fusion glycoprotein subunits of the Lassa virus GPC. These oligomannose clusters are seemingly derived as a result of sterically reduced accessibility to glycan processing enzymes, and limited amino acid diversification around these sites supports their role protecting against the humoral immune response. Combined, our data provide a structure-based blueprint for understanding how glycans render the glycoprotein spikes of Lassa virus and other Old World arenaviruses immunologically resistant targets.
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Affiliation(s)
- Yasunori Watanabe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, OX1 3QU Oxford, United Kingdom
- Division of Structural Biology, University of Oxford, OX3 7BN Oxford, United Kingdom
- Centre for Biological Sciences and Institute of Life Sciences, University of Southampton, SO17 1BJ Southampton, United Kingdom
| | - Jayna Raghwani
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, OX3 7LF Oxford, United Kingdom
| | - Joel D Allen
- Centre for Biological Sciences and Institute of Life Sciences, University of Southampton, SO17 1BJ Southampton, United Kingdom
| | - Gemma E Seabright
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, OX1 3QU Oxford, United Kingdom
- Centre for Biological Sciences and Institute of Life Sciences, University of Southampton, SO17 1BJ Southampton, United Kingdom
| | - Sai Li
- Division of Structural Biology, University of Oxford, OX3 7BN Oxford, United Kingdom
| | - Felipe Moser
- Division of Structural Biology, University of Oxford, OX3 7BN Oxford, United Kingdom
| | - Juha T Huiskonen
- Division of Structural Biology, University of Oxford, OX3 7BN Oxford, United Kingdom
- Helsinki Institute of Life Science and Molecular and Integrative Biosciences Research Program, University of Helsinki, 00014 Helsinki, Finland
| | - Thomas Strecker
- Institute of Virology, Philipps Universität Marburg, 35043 Marburg, Germany
| | - Thomas A Bowden
- Division of Structural Biology, University of Oxford, OX3 7BN Oxford, United Kingdom;
| | - Max Crispin
- Centre for Biological Sciences and Institute of Life Sciences, University of Southampton, SO17 1BJ Southampton, United Kingdom;
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Convergent immunological solutions to Argentine hemorrhagic fever virus neutralization. Proc Natl Acad Sci U S A 2017. [PMID: 28630325 DOI: 10.1073/pnas.1702127114] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Transmission of hemorrhagic fever New World arenaviruses from their rodent reservoirs to human populations poses substantial public health and economic dangers. These zoonotic events are enabled by the specific interaction between the New World arenaviral attachment glycoprotein, GP1, and cell surface human transferrin receptor (hTfR1). Here, we present the structural basis for how a mouse-derived neutralizing antibody (nAb), OD01, disrupts this interaction by targeting the receptor-binding surface of the GP1 glycoprotein from Junín virus (JUNV), a hemorrhagic fever arenavirus endemic in central Argentina. Comparison of our structure with that of a previously reported nAb complex (JUNV GP1-GD01) reveals largely overlapping epitopes but highly distinct antibody-binding modes. Despite differences in GP1 recognition, we find that both antibodies present a key tyrosine residue, albeit on different chains, that inserts into a central pocket on JUNV GP1 and effectively mimics the contacts made by the host TfR1. These data provide a molecular-level description of how antibodies derived from different germline origins arrive at equivalent immunological solutions to virus neutralization.
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