New World Clade B Arenaviruses Can Use Transferrin Receptor 1 (TfR1)-Dependent and -Independent Entry Pathways, and Glycoproteins from Human Pathogenic Strains Are Associated with the Use of TfR1

ABSTRACT Arenaviruses are rodent-borne viruses, with five members of the family capable of causing severe hemorrhagic fevers if transmitted to humans. To date, two distinct cellular receptors have been identified that are used by different pathogenic viruses, α-dystroglycan by Lassa fever virus and transferrin receptor 1 (TfR1) by certain New World clade B viruses. Our previous studies have suggested that other, as-yet-unknown receptors are involved in arenavirus entry. In the present study, we examined the use of TfR1 by the glycoproteins (GPs) from a panel of New World clade B arenaviruses comprising three pathogenic and two nonpathogenic strains. Interestingly, we found that TfR1 was only used by the GPs from the pathogenic viruses, with entry of the nonpathogenic strains being TfR1 independent. The pathogenic GPs could also direct entry into cells by TfR1-independent pathways, albeit less efficiently. A comparison of the abilities of TfR1 orthologs from different species to support arenavirus entry found that the human and feline receptors were able to enhance entry of the pathogenic strains, but that neither the murine or canine forms were functional. Since the ability to use TfR1 is a characteristic feature of the human pathogens, this interaction may represent an important target in the treatment of New World hemorrhagic fevers. In addition, the ability to use TfR1 may be a useful tool to predict the likelihood that any existing or newly discovered viruses in this family could infect humans.

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Antibody-based inhibition of pathogenic New World Hemorrhagic Fever mammarenaviruses by steric occlusion of the human transferrin receptor 1 apical domain

Journal of Virology ◽

10.1128/jvi.01868-20 ◽

2021 ◽

Author(s):

Sol Ferrero ◽

Maria D. Flores ◽

Connor Short ◽

Cecilia A. Vazquez ◽

Lars E. Clark ◽

...

Keyword(s):

Binding Site ◽

Transferrin Receptor ◽

New World ◽

Antigen Binding ◽

Hemorrhagic Fevers ◽

Apical Domain ◽

Clade B ◽

Human Transferrin Receptor ◽

Viral Particles ◽

Transferrin Receptor 1

Pathogenic Clade B New World mammarenaviruses (NWM) can cause Argentine, Venezuelan, Brazilian, and Bolivian hemorrhagic fevers. Sequence variability among NWM glycoproteins (GP) poses a challenge to the development of broadly neutralizing therapeutics against the entire clade of viruses. However, blockade of their shared binding site on the apical domain of human Transferrin Receptor 1 (hTfR1/CD71) presents an opportunity for the development of effective and broadly neutralizing therapeutics. Here we demonstrate that the murine monoclonal antibody OKT9, which targets the apical domain of hTfR1, can sterically block cellular entry by viral particles presenting Clade B NWM glycoproteins (GP1-GP2). OKT9 blockade is also effective against viral particles pseudotyped with glycoproteins of a recently identified pathogenic Sabia-like virus. With nanomolar affinity for hTfR1, the OKT9 antigen binding fragment (OKT9-Fab) sterically blocks Clade B NWM-GP1s and reduces infectivity of an attenuated strain of Junin virus. Binding of OKT9 to the hTfR1 ectodomain in its soluble, dimeric state produces stable assemblies that are observable by negative stain electron microscopy. A model of the OKT9-sTfR1 complex, informed by the known crystallographic structure of sTfR1 and a newly determined structure of the OKT9 antigen binding fragment (Fab) suggests that OKT9 and the Machupo virus GP1 share a binding site on the hTfR1 apical domain. The structural basis for this interaction presents a framework for the design and development of high-affinity, broadly acting agents targeting Clade B NWMs. Importance Pathogenic Clade B NWMs cause grave infectious diseases: the South American hemorrhagic fevers. Their etiological agents are Junin (JUNV), Guanarito (GTOV), Sabiá (SABV), Machupo (MACV), Chapare (CHAV), and a new Sabiá-like (SABV-L) virus recently identified in Brazil. These are priority A pathogens due to their high infectivity and mortality, their potential of person-to-person transmission, and the limited availability of effective therapeutics and vaccines to curb their effects. While low homology between surface glycoproteins of NWMs foils efforts to develop broadly neutralizing therapies targeting NWMs, this work provides structural evidence that OKT9, a monoclonal antibody targeting a single NWM glycoprotein binding site on hTfR1, can efficiently prevent their entry into cells.

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Host-Species Transferrin Receptor 1 Orthologs Are Cellular Receptors for Nonpathogenic New World Clade B Arenaviruses

PLoS Pathogens ◽

10.1371/journal.ppat.1000358 ◽

2009 ◽

Vol 5 (4) ◽

pp. e1000358 ◽

Cited By ~ 81

Author(s):

Jonathan Abraham ◽

Jo Ann Kwong ◽

César G. Albariño ◽

Jiajie G. Lu ◽

Sheli R. Radoshitzky ◽

...

Keyword(s):

Host Species ◽

Transferrin Receptor ◽

New World ◽

Cellular Receptors ◽

Clade B ◽

Transferrin Receptor 1

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pH-Induced Activation of Arenavirus Membrane Fusion Is Antagonized by Small-Molecule Inhibitors

Journal of Virology ◽

10.1128/jvi.01140-08 ◽

2008 ◽

Vol 82 (21) ◽

pp. 10932-10939 ◽

Cited By ~ 71

Author(s):

Joanne York ◽

Dongcheng Dai ◽

Sean M. Amberg ◽

Jack H. Nunberg

Keyword(s):

Membrane Fusion ◽

Small Molecule ◽

Viral Entry ◽

De Novo ◽

Lassa Fever ◽

Molecular Target ◽

Active Inhibitor ◽

Hemorrhagic Fevers ◽

Lassa Fever Virus ◽

Small Molecule Compound

ABSTRACT The arenavirus envelope glycoprotein (GPC) mediates viral entry through pH-induced membrane fusion in the endosome. This crucial process in the viral life cycle can be specifically inhibited in the New World arenaviruses by the small-molecule compound ST-294. Here, we show that ST-294 interferes with GPC-mediated membrane fusion by targeting the interaction of the G2 fusion subunit with the stable signal peptide (SSP). We demonstrate that amino acid substitutions at lysine-33 of the Junín virus SSP confer resistance to ST-294 and engender de novo sensitivity to ST-161, a chemically distinct inhibitor of the Old World Lassa fever virus. These compounds, as well as a broadly active inhibitor, ST-193, likely share a molecular target at the SSP-G2 interface. We also show that both ST-294 and ST-193 inhibit pH-induced dissociation of the G1 receptor-binding subunit from GPC, a process concomitant with fusion activation. Interestingly, the inhibitory activity of these molecules can in some cases be overcome by further lowering the pH used for activation. Our results suggest that these small molecules act to stabilize the prefusion GPC complex against acidic pH. The pH-sensitive interaction between SSP and G2 in GPC represents a robust molecular target for the development of antiviral compounds for the treatment of arenavirus hemorrhagic fevers.

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Old World and Clade C New World Arenaviruses Mimic the Molecular Mechanism of Receptor Recognition Used by α-Dystroglycan's Host-Derived Ligands

Journal of Virology ◽

10.1128/jvi.02574-06 ◽

2007 ◽

Vol 81 (11) ◽

pp. 5685-5695 ◽

Cited By ~ 50

Author(s):

Jillian M. Rojek ◽

Christina F. Spiropoulou ◽

Kevin P. Campbell ◽

Stefan Kunz

Keyword(s):

New World ◽

Critical Role ◽

Lassa Fever ◽

Lymphocytic Choriomeningitis ◽

Old World ◽

Ecm Proteins ◽

Receptor Recognition ◽

Lassa Fever Virus ◽

Clade C

ABSTRACT α-Dystroglycan (DG) is an important cellular receptor for extracellular matrix (ECM) proteins and also serves as the receptor for Old World arenaviruses Lassa fever virus (LFV) and lymphocytic choriomeningitis virus (LCMV) and clade C New World arenaviruses. In the host cell, α-DG is subject to a remarkably complex pattern of O glycosylation that is crucial for its interactions with ECM proteins. Two of these unusual sugar modifications, protein O mannosylation and glycan modifications involving the putative glycosyltransferase LARGE, have recently been implicated in arenavirus binding. Considering the complexity of α-DG O glycosylation, our present study was aimed at the identification of the specific O-linked glycans on α-DG that are recognized by arenaviruses. As previously shown for LCMV, we found that protein O mannosylation of α-DG is crucial for the binding of arenaviruses of distinct phylogenetic origins, including LFV, Mobala virus, and clade C New World arenaviruses. In contrast to the highly conserved requirement for O mannosylation, more generic O glycans present on α-DG are dispensable for arenavirus binding. Despite the critical role of O-mannosyl glycans for arenavirus binding under normal conditions, the overexpression of LARGE in cells deficient in O mannosylation resulted in highly glycosylated α-DG that was functional as a receptor for arenaviruses. Thus, modifications by LARGE but not O-mannosyl glycans themselves are most likely the crucial structures recognized by arenaviruses. Together, the data demonstrate that arenaviruses recognize the same highly conserved O-glycan structures on α-DG involved in ECM protein binding, indicating a strikingly similar mechanism of receptor recognition by pathogen- and host-derived ligands.

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Common Antiviral Cytotoxic T-Lymphocyte Epitope for Diverse Arenaviruses

Journal of Virology ◽

10.1128/jvi.75.14.6273-6278.2001 ◽

2001 ◽

Vol 75 (14) ◽

pp. 6273-6278 ◽

Cited By ~ 13

Author(s):

Michael B. A. Oldstone ◽

Hanna Lewicki ◽

Dirk Homann ◽

Christophe Nguyen ◽

Sylvianne Julien ◽

...

Keyword(s):

Amino Acids ◽

T Lymphocyte ◽

New World ◽

Cytotoxic T Lymphocyte ◽

Lassa Fever ◽

Lymphocytic Choriomeningitis ◽

Target Cells ◽

Old World ◽

Ctl Epitope ◽

Lassa Fever Virus

ABSTRACT Members of the Arenaviridae family have been isolated from mammalian hosts in disparate geographic locations, leading to their grouping as Old World types (i.e., lymphocytic choriomeningitis virus [LCMV], Lassa fever virus [LFV], Mopeia virus, and Mobala virus) and New World types (i.e., Junin, Machupo, Tacaribe, and Sabia viruses) (C. J. Peters, M. J. Buchmeier, P. E. Rollin, and T. G. Ksiazek, p. 1521–1551, in B. N. Fields, D. M. Knipe, and P. M. Howley [ed.], Fields virology, 3rd ed., 1996; P. J. Southern, p. 1505–1519, in B. N. Fields, D. M. Knipe, and P. M. Howley [ed.], Fields virology, 3rd ed., 1996). Several types in both groups—LFV, Junin, Machupo, and Sabia viruses—cause severe and often lethal human diseases. By sequence comparison, we noted that eight Old World and New World arenaviruses share several amino acids with the nucleoprotein (NP) that consists of amino acids (aa) 118 to 126 (NP 118–126) (RPQASGVYM) of LCMV that comprise the immunodominant cytotoxic T-lymphocyte (CTL) epitope forH-2 d mice (32). This Ld-restricted epitope constituted >97% of the total bulk CTLs produced in the specific antiviral or clonal responses ofH-2 d BALB mice. NP 118–126 of the Old World arenaviruses LFV, Mopeia virus, and LCMV and the New World arenavirus Sabia virus bound at high affinity to Ld. The primary H-2 d CTL anti-LCMV response as well as that of a CTL clone responsive to LCMV NP 118–126 recognized target cells coated with NP 118–126 peptides derived from LCMV, LFV, and Mopeia virus but not Sabia virus, indicating that a common functional NP epitope exists among Old World arenaviruses. Use of site-specific amino acid exchanges in the NP CTL epitope among these arenaviruses identified amino acids involved in major histocompatibility complex binding and CTL recognition.

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Investigation of Clade B New World Arenavirus Tropism by Using Chimeric GP1 Proteins

Journal of Virology ◽

10.1128/jvi.01625-09 ◽

2009 ◽

Vol 84 (2) ◽

pp. 1176-1182 ◽

Cited By ~ 9

Author(s):

Vanessa K. Martin ◽

Magali E. Droniou-Bonzom ◽

Therese Reignier ◽

Jill E. Oldenburg ◽

Alex U. Cox ◽

...

Keyword(s):

Central Region ◽

Transferrin Receptor ◽

New World ◽

Receptor Type ◽

Human Transferrin ◽

Clade B ◽

Human Transferrin Receptor ◽

Machupo Virus ◽

Different Characteristics

ABSTRACT Clade B of the New World arenaviruses contains both pathogenic and nonpathogenic members, whose surface glycoproteins (GPs) are characterized by different abilities to use the human transferrin receptor type 1 (hTfR1) protein as a receptor. Using closely related pairs of pathogenic and nonpathogenic viruses, we investigated the determinants of the GP1 subunit that confer these different characteristics. We identified a central region (residues 85 to 221) in the Guanarito virus GP1 that was sufficient to interact with hTfR1, with residues 159 to 221 being essential. The recently solved structure of part of the Machupo virus GP1 suggests an explanation for these requirements.

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Transferrin receptor 1 is a cellular receptor for New World haemorrhagic fever arenaviruses

Nature ◽

10.1038/nature05539 ◽

2007 ◽

Vol 446 (7131) ◽

pp. 92-96 ◽

Cited By ~ 272

Author(s):

Sheli R. Radoshitzky ◽

Jonathan Abraham ◽

Christina F. Spiropoulou ◽

Jens H. Kuhn ◽

Dan Nguyen ◽

...

Keyword(s):

Transferrin Receptor ◽

New World ◽

Cellular Receptor ◽

Haemorrhagic Fever ◽

Transferrin Receptor 1

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Lassa Fever Virus Binds Matriglycan—A Polymer of Alternating Xylose and Glucuronate—On α-Dystroglycan

Viruses ◽

10.3390/v13091679 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1679

Author(s):

Soumya Joseph ◽

Kevin P. Campbell

Keyword(s):

Viral Entry ◽

Tyrosine Kinases ◽

Lassa Fever ◽

Fever Virus ◽

Phagocytic Cells ◽

Hemorrhagic Fevers ◽

Lassa Fever Virus ◽

Clade C ◽

Additional Cell ◽

Life Threatening

Lassa fever virus (LASV) can cause life-threatening hemorrhagic fevers for which there are currently no vaccines or targeted treatments. The late Prof. Stefan Kunz, along with others, showed that the high-affinity host receptor for LASV, and other Old World and clade-C New World mammarenaviruses, is matriglycan—a linear repeating disaccharide of alternating xylose and glucuronic acid that is polymerized uniquely on α-dystroglycan by like-acetylglucosaminyltransferase-1 (LARGE1). Although α-dystroglycan is ubiquitously expressed, LASV preferentially infects vascular endothelia and professional phagocytic cells, which suggests that viral entry requires additional cell-specific factors. In this review, we highlight the work of Stefan Kunz detailing the molecular mechanism of LASV binding and discuss the requirements of receptors, such as tyrosine kinases, for internalization through apoptotic mimicry.

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Rational design of universal immunotherapy for TfR1-tropic arenaviruses

Nature Communications ◽

10.1038/s41467-019-13924-6 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 3

Author(s):

Hadas Cohen-Dvashi ◽

Ron Amon ◽

Krystle N. Agans ◽

Robert W. Cross ◽

Aliza Borenstein-Katz ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Rational Design ◽

Biological Weapons ◽

Hemorrhagic Fevers ◽

Transferrin Receptor 1 ◽

Viral Glycoproteins ◽

Life Threatening ◽

Pathogenic Viruses ◽

Rodent Populations ◽

Reactive Molecule

AbstractCertain arenaviruses that circulate in rodent populations can cause life-threatening hemorrhagic fevers when they infect humans. Due to their efficient transmission, arenaviruses pose a severe risk for outbreaks and might be exploited as biological weapons. Effective countermeasures against these viruses are highly desired. Ideally, a single remedy would be effective against many or even all the pathogenic viruses in this family. However, despite the fact that all pathogenic arenaviruses from South America utilize transferrin receptor 1 (TfR1) as a cellular receptor, their viral glycoproteins are highly diversified, impeding efforts to isolate cross-neutralizing antibodies. Here we address this problem using a rational design approach to target TfR1-tropic arenaviruses with high potency and breadth. The pan-reactive molecule is highly effective against all arenaviruses that were tested, offering a universal therapeutic approach. Our design scheme avoids the shortcomings of previous immunoadhesins and can be used to combat other zoonotic pathogens.

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