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Shaw AB, Tse HN, Byford O, Plahe G, Moon-Walker A, Hover SE, Saphire EO, Whelan SPJ, Mankouri J, Fontana J, Barr JN. Cellular endosomal potassium ion flux regulates arenavirus uncoating during virus entry. mBio 2024:e0168423. [PMID: 38874413 DOI: 10.1128/mbio.01684-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 03/21/2024] [Indexed: 06/15/2024] Open
Abstract
Lymphocytic choriomeningitis virus (LCMV) is an enveloped and segmented negative-sense RNA virus classified within the Arenaviridae family of the Bunyavirales order. LCMV is associated with fatal disease in immunocompromised populations and, as the prototypical arenavirus member, acts as a model for the many highly pathogenic members of the Arenaviridae family, such as Junín, Lassa, and Lujo viruses, all of which are associated with devastating hemorrhagic fevers. To enter cells, the LCMV envelope fuses with late endosomal membranes, for which two established requirements are low pH and interaction between the LCMV glycoprotein (GP) spike and secondary receptor CD164. LCMV subsequently uncoats, where the RNA genome-associated nucleoprotein (NP) separates from the Z protein matrix layer, releasing the viral genome into the cytosol. To further examine LCMV endosome escape, we performed an siRNA screen which identified host cell potassium ion (K+) channels as important for LCMV infection, with pharmacological inhibition confirming K+ channel involvement during the LCMV entry phase completely abrogating productive infection. To better understand the K+-mediated block in infection, we tracked incoming virions along their entry pathway under physiological conditions, where uncoating was signified by separation of NP and Z proteins. In contrast, K+ channel blockade prevented uncoating, trapping virions within Rab7 and CD164-positive endosomes, identifying K+ as a third LCMV entry requirement. K+ did not increase GP-CD164 binding or alter GP-CD164-dependent fusion. Thus, we propose that K+ mediates uncoating by modulating NP-Z interactions within the virion interior. These results suggest K+ channels represent a potential anti-arenaviral target.IMPORTANCEArenaviruses can cause fatal human disease for which approved preventative or therapeutic options are not available. Here, using the prototypical LCMV, we identified K+ channels as critical for arenavirus infection, playing a vital role during the entry phase of the infection cycle. We showed that blocking K+ channel function resulted in entrapment of LCMV particles within late endosomal compartments, thus preventing productive replication. Our data suggest K+ is required for LCMV uncoating and genome release by modulating interactions between the viral nucleoprotein and the matrix protein layer inside the virus particle.
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Affiliation(s)
- Amelia B Shaw
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Hiu Nam Tse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Owen Byford
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Grace Plahe
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Alex Moon-Walker
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, California, USA
- Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, Missouri, USA
- Program in Virology, Harvard Medical School, Boston, Massachusetts, USA
| | - Samantha E Hover
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Erica Ollmann Saphire
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, California, USA
| | - Sean P J Whelan
- Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jamel Mankouri
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Juan Fontana
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - John N Barr
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
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2
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Cline C, Zeng X, Bell TM, Shaia C, Facemire P, Williams J, Davis N, Babka A, Picado E, Fitzpatrick C, Golden JW. Temporal changes in pathology and viral RNA distribution in guinea pigs following separate infection with two New World Arenaviruses. PLoS Negl Trop Dis 2023; 17:e0011620. [PMID: 37682988 PMCID: PMC10511090 DOI: 10.1371/journal.pntd.0011620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 09/20/2023] [Accepted: 08/22/2023] [Indexed: 09/10/2023] Open
Abstract
Numerous arenaviruses have been identified throughout the Americas and a subset of these viruses cause viral hemorrhagic fever in humans. This study compared the pathology and viral RNA distribution in Hartley guinea pigs challenged with two human-disease causing New World arenaviruses, Junin virus (JUNV) or Guanarito virus (GTOV). Histopathologic analysis and RNA in situ hybridization revealed similar pathology and viral RNA distribution for both groups of animals challenged with either JUNV or GTOV on days 3, 7, 10 and 12 post exposure (PE). Gross lesions were first observed on day 7 and primarily involved the lungs and liver. The most severe histologic lesions occurred in the lymph nodes, spleen, and thymus and included lymphoid depletion and necrosis which increased in severity over time. Extensive necrosis was also observed in the bone marrow on day 12. Minimal to mild inflammation with and without necrosis was observed in the choroid plexus of the brain, choroid of the eye, intestinal tract, lung and adrenal gland. Significant liver lesions were rare, consisting predominantly of hepatocyte vacuolation. Viral RNA labeling was identified in nearly all organs examined, was often extensive in certain organs and generally increased over time starting on day 7. Our data demonstrate the guinea pig may serve as a useful model to study New World arenavirus infection in humans and for the evaluation and development of medical countermeasures.
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Affiliation(s)
- Curtis Cline
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Xiankun Zeng
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Todd M. Bell
- Foundational Sciences Directorate, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Carl Shaia
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Paul Facemire
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Janice Williams
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Neil Davis
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - April Babka
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Edwin Picado
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Colin Fitzpatrick
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Joseph W. Golden
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
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3
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Grant DS, Samuels RJ, Garry RF, Schieffelin JS. Lassa Fever Natural History and Clinical Management. Curr Top Microbiol Immunol 2023. [PMID: 37106159 DOI: 10.1007/82_2023_263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Lassa fever is caused by Lassa virus (LASV), an Old World Mammarenavirus that is carried by Mastomys natalensis and other rodents. It is endemic in Sierra Leone, Nigeria, and other countries in West Africa. The clinical presentation of LASV infection is heterogenous varying from an inapparent or mild illness to a fatal hemorrhagic fever. Exposure to LASV is usually through contact with rodent excreta. After an incubation period of 1-3 weeks, initial symptoms such as fever, headache, and fatigue develop that may progress to sore throat, retrosternal chest pain, conjunctival injection, vomiting, diarrhea, and abdominal pain. Severe illness, including hypotension, shock, and multiorgan failure, develops in a minority of patients. Patient demographics and case fatality rates are distinctly different in Sierra Leone and Nigeria. Laboratory diagnosis relies on the detection of LASV antigens or genomic RNA. LASV-specific immunoglobulin G and M assays can also contribute to clinical management. The mainstay of treatment for Lassa fever is supportive care. The nucleoside analog ribavirin is commonly used to treat acute Lassa fever but is considered useful only if treatment is begun early in the disease course. Drugs in development, including a monoclonal antibody cocktail, have the potential to impact the management of Lassa fever.
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Affiliation(s)
- Donald S Grant
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health, Kenema, Sierra Leone
- College of Medicine and Allied Health Sciences (COMAHS), University of Sierra Leone, Freetown, Sierra Leone
| | - Robert J Samuels
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health, Kenema, Sierra Leone
| | - Robert F Garry
- School of Medicine, Department of Microbiology and Immunology, Tulane University, New Orleans, LA, 70112, USA
- Zalgen Labs, Frederick, MD, 21703, USA
- Global Virus Network (GVN), Baltimore, MD, 21201, USA
| | - John S Schieffelin
- School of Medicine, Department of Pediatrics, Tulane University, New Orleans, LA, 70112, USA.
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Karnam S, Huang Y, Nguyen N, Yeh S. Ophthalmic consequences of viral hemorrhagic fevers: Insights from the clinic and laboratory. FRONTIERS IN TROPICAL DISEASES 2023. [DOI: 10.3389/fitd.2023.1107786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Viral hemorrhagic fevers (VHFs) are a diverse group of RNA virus-mediated systemic diseases with significant morbidity and mortality and represent a significant public health concern. Given the high systemic morbidity and mortality in a number of these entities, delays in diagnosis can lead to downstream public health consequences. Many viral hemorrhagic fevers have ophthalmic manifestations and ophthalmologists thus play a key role in disease recognition and the management of ocular complications associated with specific hemorrhagic fevers. This review summarizes the key ophthalmic consequences of viral hemorrhagic fevers, viral disease pathogenesis, disease findings, and areas of unmet research need.
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de Oliveira ALR, Cunha MS, Bisordi I, de Souza RP, Timenetsky MDCST. Serological evidence of arenavirus circulation in wild rodents from central-west, southeast, and south regions of Brazil, 2002-2006. Braz J Microbiol 2023; 54:279-284. [PMID: 36441413 PMCID: PMC9943984 DOI: 10.1007/s42770-022-00858-3] [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: 03/24/2022] [Accepted: 10/24/2022] [Indexed: 11/30/2022] Open
Abstract
Viral hemorrhagic fevers caused by arenaviruses are severe zoonotic diseases. In reservoirs, the presence of antibodies may indicate viral circulation in a population of a specific region, and these data can be used as an indicator for further investigations by molecular techniques. The present study aimed to detect the presence of arenavirus antibodies in wild rodents captured from 1998 to 2008 during epidemiological surveillance activities. A retrospective analysis of 2243 wild rodent blood samples using a broad cross-reactive in-house developed enzyme-linked immunosorbent assay (ELISA) revealed a 0.44% (10/2243) positive rate in wild rodents, which included Necromys lasiurus (6/1012), Calomys callosus (2/94), and Akodon sp. (2/273) species. These rodents were captured between 2002 to 2006 in Campo Alegre de Goiás/GO, Bodoquena/MS, Nuporanga/SP, and Mogi das Cruzes/SP. Our findings suggest the sylvatic circulation of arenavirus among wild rodents in the southeast region of Brazil. However, future virological and molecular studies are necessary to confirm the viral presence in these regions.
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Affiliation(s)
- Ana Lúcia Rodrigues de Oliveira
- Núcleo de Doenças de Transmissão Vetorial Do Centro de Virologia do Instituto Adolfo Lutz, SP, São Paulo, Brazil.
- Programa de Pós-Graduação Em Ciências, Mestrado Em Pesquisa Laboratoriais Em Saúde Pública da Coordenadoria de Controle de Doenças da Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brazil.
| | - Mariana Sequetin Cunha
- Núcleo de Doenças de Transmissão Vetorial Do Centro de Virologia do Instituto Adolfo Lutz, SP, São Paulo, Brazil.
| | - Ivani Bisordi
- Núcleo de Doenças de Transmissão Vetorial Do Centro de Virologia do Instituto Adolfo Lutz, SP, São Paulo, Brazil
| | - Renato Pereira de Souza
- Núcleo de Doenças de Transmissão Vetorial Do Centro de Virologia do Instituto Adolfo Lutz, SP, São Paulo, Brazil
| | - Maria do Carmo Sampaio Tavares Timenetsky
- Programa de Pós-Graduação Em Ciências, Mestrado Em Pesquisa Laboratoriais Em Saúde Pública da Coordenadoria de Controle de Doenças da Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brazil
- Centro de Virologia Do, Instituto Adolfo Lutz, São Paulo, SP, Brazil
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Molecular Engineering of a Mammarenavirus with Unbreachable Attenuation. J Virol 2023; 97:e0138522. [PMID: 36533953 PMCID: PMC9888291 DOI: 10.1128/jvi.01385-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Several mammarenaviruses cause severe hemorrhagic fever (HF) disease in humans and pose important public health problems in their regions of endemicity. There are no United States (US) Food and Drug Administration (FDA)-approved mammarenavirus vaccines, and current anti-mammarenavirus therapy is limited to an off-label use of ribavirin that has limited efficacy. Mammarenaviruses are enveloped viruses with a bi-segmented negative-strand RNA genome. Each genome segment contains two open reading frames (ORF) separated by a noncoding intergenic region (IGR). The large (L) segment encodes the RNA dependent RNA polymerase, L protein, and the Z matrix protein, whereas the small (S) segment encodes the surface glycoprotein precursor (GPC) and nucleoprotein (NP). In the present study, we document the generation of a recombinant form of the prototypic mammarenavirus lymphocytic choriomeningitis virus (LCMV) expressing a codon deoptimized (CD) GPC and containing the IGR of the S segment in both the S and L segments (rLCMV/IGR-CD). We show that rLCMV/IGR-CD is fully attenuated in C57BL/6 (B6) mice but able to provide complete protection upon a single administration against a lethal challenge with LCMV. Importantly, rLCMV/IGR-CD exhibited an unbreachable attenuation for its safe implementation as a live-attenuated vaccine (LAV). IMPORTANCE Several mammarenaviruses cause severe disease in humans and pose important public health problems in their regions of endemicity. Currently, no FDA-licensed mammarenavirus vaccines are available, and anti-mammarenaviral therapy is limited to an off-label use of ribavirin whose efficacy is controversial. Here, we describe the generation of recombinant version of the prototypic mammarenavirus lymphocytic choriomeningitis virus (rLCMV) combining the features of a codon deoptimized (CD) GPC and the noncoding intergenic region (IGR) of the S segment in both S and L genome segments, called rLCMV/IGR-CD. We present evidence that rLCMV/IGR-CD has excellent safety and protective efficacy features as live-attenuated vaccine (LAV). Importantly, rLCMV/IGR-CD prevents, in coinfected mice, the generation of LCMV reassortants with increased virulence. Our findings document a well-defined molecular strategy for the generation of mammarenavirus LAV candidates able to trigger long-term protective immunity, upon a single immunization, while exhibiting unique enhanced safety features, including unbreachable attenuation.
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7
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Batiha GES, Moubarak M, Shaheen HM, Zakariya AM, Usman IM, Rauf A, Adhikari A, Dey A, Alexiou A, Hetta HF, Al-Gareeb AI, Al-Kuraishy HM. Favipiravir in SARS-CoV-2 Infection: Is it Worth it? Comb Chem High Throughput Screen 2022; 25:2413-2428. [PMID: 35430987 DOI: 10.2174/1386207325666220414111840] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 12/27/2021] [Accepted: 01/13/2022] [Indexed: 01/27/2023]
Abstract
Favipiravir is a potential antiviral drug undergoing clinical trials to manage various viral infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Favipiravir possesses antiviral properties against RNA viruses, including SARS-CoV-2. Unfortunately, these viruses do not have authorized antiviral drugs for the management of diseases resulting from their infection, hence the dire need to accentuate the discovery of antiviral drugs that are efficacious and have a broad spectrum. Favipiravir acts primarily by blocking inward and outward movements of the virus from cells. Favipiravir is a prodrug undergoing intracellular phosphorylation and ribosylation to form an active form, favipiravir-RTP, which binds viral RNA-dependent RNA polymerase (RdRp). Considering the novel mechanism of favipiravir action, especially in managing viral infections, it is vital to pay more attention to the promised favipiravir hold in the management of SARS-CoV-2, its efficacy, and dosage regimen, and interactions with other drugs. In conclusion, favipiravir possesses antiviral properties against RNA viruses, including COVID- 19. Favipiravir is effective against SARS-CoV-2 infection through inhibition of RdRp. Pre-clinical and large-scalp prospective studies are recommended for efficacy and long-term safety of favipiravir in COVID-19.
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Affiliation(s)
- Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, AlBeheira, Egypt
| | - Mohamed Moubarak
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, AlBeheira, Egypt
| | - Hazem M Shaheen
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, AlBeheira, Egypt
| | - Ali M Zakariya
- Department of Biological Sciences, Sule Lamido University Kafin, Hausa, Nigeria
| | - Ibe M Usman
- Faculty of Biomedical Sciences, Kampala International University Western Campus, Bushenyi, Uganda
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Swabi, Anbar, KP, Pakistan
| | - Achyut Adhikari
- Central Department of Chemistry, Tribhuvan University, Kritipur, Nepal
| | - Abhijit Dey
- Department. of Life Sciences, Presidency University, Kolkata, India
| | - Athanasios Alexiou
- Department of Science and Engineering, Novel Global Community Educational Foundation, Australia and AFNP Med, Austria
| | - Helal F Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt
| | - Ali I Al-Gareeb
- Department of Clinical Pharmacology, Medicine and Therapeutic, Medical Faculty, College of Medicine, Al-Mustansiriyah University, P.O. Box 14132, Baghdad, Iraq
| | - Hayder M Al-Kuraishy
- Department of Clinical Pharmacology, Medicine and Therapeutic, Medical Faculty, College of Medicine, Al-Mustansiriyah University, P.O. Box 14132, Baghdad, Iraq
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Villalaín J. Interaction of Lassa virus fusion and membrane proximal peptides with late endosomal membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184031. [PMID: 35964711 DOI: 10.1016/j.bbamem.2022.184031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/15/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
Mammarenaviruses include many significant worldwide-widespread human pathogens, among them Lassa virus (LASV), having a dramatic morbidity and mortality rate. They are a potential high-risk menace to the worldwide public health since there are no treatments and there is a high possibility of animal-to-human and human-to-human viral transmission. These viruses enter into the cells by endocytosis fusing its membrane envelope with the late endosomal membrane thanks to the glycoprotein GP2, a membrane fusion protein of class I. This protein contains different domains, among them the N-terminal fusion peptide (NFP), the internal fusion loop (IFL), the membrane proximal external region (MPER) and the transmembrane domain (TMD). All these domains are implicated in the membrane fusion process. In this work, we have used an all-atom molecular dynamics study to know the binding of these protein domains with a complex membrane mimicking the late endosome one. We show that the NFP/IFL domain is capable of spontaneously inserting into the membrane without a significant change of secondary structure, the MPER domain locates at the bilayer interface with an orientation parallel to the membrane surface and tends to interact with other MPER domains, and the TMD domain tilts inside the bilayer. Moreover, they predominantly interact with negatively charged phospholipids. Overall, these membrane-interacting domains would characterise a target that would make possible to find effective antiviral molecules against LASV in particular and Mammarenaviruses in general.
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Affiliation(s)
- José Villalaín
- Institute of Research, Development, and Innovation in Healthcare Biotechnology (IDiBE), Universitas "Miguel Hernández", E-03202 Elche-Alicante, Spain.
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Silva-Ramos CR, Montoya-Ruíz C, Faccini-Martínez ÁA, Rodas JD. An updated review and current challenges of Guanarito virus infection, Venezuelan hemorrhagic fever. Arch Virol 2022; 167:1727-1738. [PMID: 35579715 PMCID: PMC9110938 DOI: 10.1007/s00705-022-05453-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 03/08/2022] [Indexed: 11/30/2022]
Abstract
Guanarito virus (GTOV) is a member of the family Arenaviridae and has been designated a category A bioterrorism agent by the US Centers for Disease Control and Prevention. It is endemic to Venezuela's western region, and it is the etiological agent of "Venezuelan hemorrhagic fever" (VHF). Similar to other arenaviral hemorrhagic fevers, VHF is characterized by fever, mild hemorrhagic signs, nonspecific symptoms, thrombocytopenia, and leukopenia. Patients with severe disease usually develop signs of internal bleeding. Due to the absence of reference laboratories that can handle GTOV in endemic areas, diagnosis is primarily clinical and epidemiological. No antiviral therapies are available; thus, treatment includes only supportive analgesia and fluids. GTOV is transmitted by contact with the excreta of its rodent reservoir, Zygodontomys brevicauda. The main reasons for the emergence of the disease may be the increase in the human population, migration, and changes in land use patterns in rural areas. Social and environmental changes could make VHF an important cause of underdiagnosed acute febrile illnesses in regions near the endemic areas. Although there is evidence that GTOV circulates among rodents in different Venezuelan states, VHF cases have only been reported in the states of Portuguesa and Barinas. However, due to the increased frequency of invasions by humans into wildlife habitats, it is probable that VHF could become a public health problem in the nearby regions of Colombia and Brazil. The current Venezuelan political crisis is causing an increase in the migration of people and livestock, representing a risk for the redistribution and re-emergence of infectious diseases.
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Affiliation(s)
- Carlos Ramiro Silva-Ramos
- Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Carolina Montoya-Ruíz
- Facultad de Ciencias, Universidad Nacional de Colombia, Carrera 65, #59a, 110, Medellín, Antioquia, Colombia.
| | - Álvaro A Faccini-Martínez
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA.,Comité de Medicina Tropical, Zoonosis y Medicina del Viajero, Asociación Colombiana de Infectología, Bogotá, Colombia
| | - Juan David Rodas
- Grupo de Investigación en Ciencias Veterinarias Centauro, Universidad de Antioquia, Medellín, Colombia
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Lassa virus glycoprotein complex review: insights into its unique fusion machinery. Biosci Rep 2022; 42:230708. [PMID: 35088070 PMCID: PMC8844875 DOI: 10.1042/bsr20211930] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Lassa virus (LASV), an arenavirus endemic to West Africa, causes Lassa fever—a lethal hemorrhagic fever. Entry of LASV into the host cell is mediated by the glycoprotein complex (GPC), which is the only protein located on the viral surface and comprises three subunits: glycoprotein 1 (GP1), glycoprotein 2 (GP2), and a stable signal peptide (SSP). The LASV GPC is a class one viral fusion protein, akin to those found in viruses such as human immunodeficiency virus (HIV), influenza, Ebola virus (EBOV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). These viruses are enveloped and utilize membrane fusion to deliver their genetic material to the host cell. Like other class one fusion proteins, LASV-mediated membrane fusion occurs through an orchestrated sequence of conformational changes in its GPC. The receptor-binding subunit, GP1, first engages with a host cell receptor then undergoes a unique receptor switch upon delivery to the late endosome. The acidic pH and change in receptor result in the dissociation of GP1, exposing the fusion subunit, GP2, such that fusion can occur. These events ultimately lead to the formation of a fusion pore so that the LASV genetic material is released into the host cell. Interestingly, the mature GPC retains its SSP as a third subunit—a feature that is unique to arenaviruses. Additionally, the fusion domain contains two separate fusion peptides, instead of a standard singular fusion peptide. Here, we give a comprehensive review of the LASV GPC components and their unusual features.
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Malhotra H, Kumar A. Codon usage signatures in Sabia and Chapare for host adaptation. Bioinformation 2021; 17:891-898. [PMID: 35574503 PMCID: PMC9070627 DOI: 10.6026/97320630017891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/16/2021] [Accepted: 10/16/2021] [Indexed: 11/23/2022] Open
Abstract
Sabia and Chapare viruses in the Arenavirus family cause viral hemorrhagic fever among humans with a fatality rate of 30% with no treatment models. Therefore, it is of interest to document the codon usage, amino acid patterns and associated factors influencing the observed variations in Sabia and Chapare viruses for host adaptation. Multivariate statistical analysis revealed compositional constraint and host selection pressure influencing the viral codon usage patterns. These data suggests the codon usage signatures in Sabia and Chapare viruses for host adaptation in the human host implying its role in the rapid progression of the infection. Dinucleotides UpG and CpA were noted to be over-represented among the Sabia, Chapare viruses and human genomes. Strong restraint from the usage of CpG dinucleotides among viruses is linked with the molecular mimicry of the human immune system. Thus, the data reported from this study help in understanding the mechanism of viral adaptation inside the host genome for further consideration in drug discovery.
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Affiliation(s)
- Himani Malhotra
- Department of Biotechnology, School of Bioengineering and Biosciences, Lovely Professional University, Jalandhar Delhi G.T. Road, Phagwara, Punjab, INDIA -144411
| | - Arvind Kumar
- Department of Biochemistry, School of Bioengineering and Biosciences, Lovely Professional University, Jalandhar Delhi G.T. Road, Phagwara, Punjab, INDIA -144411
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12
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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. J Virol 2021; 95:e0186820. [PMID: 34132574 PMCID: PMC8354235 DOI: 10.1128/jvi.01868-20] [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: 12/24/2022] Open
Abstract
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 for 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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Kim YJ, Venturini V, de la Torre JC. Progress in Anti-Mammarenavirus Drug Development. Viruses 2021; 13:v13071187. [PMID: 34206216 PMCID: PMC8310104 DOI: 10.3390/v13071187] [Citation(s) in RCA: 3] [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: 05/25/2021] [Revised: 06/12/2021] [Accepted: 06/19/2021] [Indexed: 12/24/2022] Open
Abstract
Mammarenaviruses are prevalent pathogens distributed worldwide, and several strains cause severe cases of human infections with high morbidity and significant mortality. Currently, there is no FDA-approved antiviral drugs and vaccines against mammarenavirus and the potential treatment option is limited to an off-label use of ribavirin that shows only partial protective effect and associates with side effects. For the past few decades, extensive research has reported potential anti-mammarenaviral drugs and their mechanisms of action in host as well as vaccine candidates. This review describes current knowledge about mammarenavirus virology, progress of antiviral drug development, and technical strategies of drug screening.
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Affiliation(s)
- Yu-Jin Kim
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (V.V.)
| | - Victor Venturini
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (V.V.)
- Department of Biotechnology, Faculty of Experimental Sciences, Francisco de Vitoria University (UFV), Carretera Pozuelo-Majadahonda, Km 1,800, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Juan C. de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (V.V.)
- Correspondence:
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14
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Azim KF, Lasker T, Akter R, Hia MM, Bhuiyan OF, Hasan M, Hossain MN. Combination of highly antigenic nucleoproteins to inaugurate a cross-reactive next generation vaccine candidate against Arenaviridae family. Heliyon 2021; 7:e07022. [PMID: 34041391 PMCID: PMC8144012 DOI: 10.1016/j.heliyon.2021.e07022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 02/09/2021] [Accepted: 05/05/2021] [Indexed: 12/28/2022] Open
Abstract
Arenaviral infections often result lethal hemorrhagic fevers, affecting primarily in African and South American regions. To date, there is no FDA-approved licensed vaccine against arenaviruses and treatments have been limited to supportive therapy. Hence, the study was employed to design a highly immunogenic cross-reactive vaccine against Arenaviridae family using reverse vaccinology approach. The whole proteome of Lassa virus (LASV), Lymphocytic Choriomeningitis virus (LCMV), Lujo virus and Guanarito virus were retrieved and assessed to determine the most antigenic viral proteins. Both T-cell and B-cell epitopes were predicted and screened based on transmembrane topology, antigenicity, allergenicity, toxicity and molecular docking analysis. The final constructs were designed using different adjuvants, top epitopes, PADRE sequence and respective linkers and were assessed for the efficacy, safety, stability and molecular cloning purposes. The proposed epitopes were highly conserved (84%–100%) and showed greater cumulative population coverage. Moreover, T cell epitope GWPYIGSRS was conserved in Junin virus (Argentine mammarenavirus) and Sabia virus (Brazilian mammarenavirus), while B cell epitope NLLYKICLSG was conserved in Machupo virus (Bolivian mammarenavirus) and Sabia virus, indicating the possibility of final vaccine construct to confer a broad range immunity in the host. Docking analysis of the refined vaccine with different MHC molecules and human immune receptors were biologically significant. The vaccine-receptor (V1-TLR3) complex showed minimal deformability at molecular level and was compatible for cloning into pET28a(+) vector of E. coli strain K12. The study could be helpful in developing vaccine to combat arenaviral infections in the future. However, further in vitro and in vivo trials using model animals are highly recommended for the experimental validation of our findings.
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Affiliation(s)
- Kazi Faizul Azim
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh.,Department of Microbial Biotechnology, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Tahera Lasker
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Rahima Akter
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Mantasha Mahmud Hia
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Omar Faruk Bhuiyan
- Department of Genetic Engineering and Biotechnology, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh
| | - Mahmudul Hasan
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh.,Department of Pharmaceuticals and Industrial Biotechnology, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Md Nazmul Hossain
- Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh.,Department of Microbial Biotechnology, Sylhet Agricultural University, Sylhet 3100, Bangladesh
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15
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Pathogen Dose in Animal Models of Hemorrhagic Fever Virus Infections and the Potential Impact on Studies of the Immune Response. Pathogens 2021; 10:pathogens10030275. [PMID: 33804381 PMCID: PMC7999429 DOI: 10.3390/pathogens10030275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/22/2021] [Accepted: 02/25/2021] [Indexed: 12/24/2022] Open
Abstract
Viral hemorrhagic fever viruses come from a wide range of virus families and are a significant cause of morbidity and mortality worldwide each year. Animal models of infection with a number of these viruses have contributed to our knowledge of their pathogenesis and have been crucial for the development of therapeutics and vaccines that have been approved for human use. Most of these models use artificially high doses of virus, ensuring lethality in pre-clinical drug development studies. However, this can have a significant effect on the immune response generated. Here I discuss how the dose of antigen or pathogen is a critical determinant of immune responses and suggest that the current study of viruses in animal models should take this into account when developing and studying animal models of disease. This can have implications for determination of immune correlates of protection against disease as well as informing relevant vaccination and therapeutic strategies.
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16
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Frank MG, Beitscher A, Webb CM, Raabe V. South American Hemorrhagic Fevers: A summary for clinicians. Int J Infect Dis 2021; 105:505-515. [PMID: 33610781 DOI: 10.1016/j.ijid.2021.02.046] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES This article is one of a series on acute, severe diseases of humans caused by emerging viruses for which there are no or limited licensed medical countermeasures. We approached this summary on South American Hemorrhagic Fevers (SAHF) from a clinical perspective that focuses on pathogenesis, clinical features, and diagnostics with an emphasis on therapies and vaccines that have demonstrated potential for use in an emergency situation through their evaluation in nonhuman primates (NHPs) and/or in humans. METHODS A standardized literature review was conducted on the clinical, pathological, vaccine, and treatment factors for SAHF as a group and for each individual virus/disease. RESULTS We identified 2 treatments and 1 vaccine platform that have demonstrated potential benefit for treating or preventing infection in humans and 4 other potential treatments currently under investigation. CONCLUSION We provide succinct summaries of these countermeasures to give the busy clinician a head start in reviewing the literature if faced with a patient with South American Hemorrhagic Fever. We also provide links to other authoritative sources of information.
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Affiliation(s)
- Maria G Frank
- Denver Health and Hospital Authority, Denver, CO, United States.
| | - Adam Beitscher
- Denver Health and Hospital Authority, Denver, CO, United States.
| | - Camille M Webb
- University of Texas Medical Branch, Galveston, TX, United States.
| | - Vanessa Raabe
- New York University Grossman School of Medicine, New York, NY, United States.
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17
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Huang Q, Liu X, Brisse M, Ly H, Liang Y. Effect of Strain Variations on Lassa Virus Z Protein-Mediated Human RIG-I Inhibition. Viruses 2020; 12:E907. [PMID: 32824946 PMCID: PMC7551410 DOI: 10.3390/v12090907] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/12/2020] [Accepted: 08/16/2020] [Indexed: 11/21/2022] Open
Abstract
Mammarenaviruses include several known human pathogens, such as the prototypic lymphocytic choriomeningitis virus (LCMV) that can cause neurological diseases and Lassa virus (LASV) that causes endemic hemorrhagic fever infection. LASV-infected patients show diverse clinical manifestations ranging from asymptomatic infection to hemorrhage, multi-organ failures and death, the mechanisms of which have not been well characterized. We have previously shown that the matrix protein Z of pathogenic arenaviruses, including LASV and LCMV, can strongly inhibit the ability of the innate immune protein RIG-I to suppress type I interferon (IFN-I) expression, which serves as a mechanism of viral immune evasion and virulence. Here, we show that Z proteins of diverse LASV isolates derived from rodents and humans have a high degree of sequence variations at their N- and C-terminal regions and produce variable degrees of inhibition of human RIG-I (hRIG-I) function in an established IFN-β promoter-driven luciferase (LUC) reporter assay. Additionally, we show that Z proteins of four known LCMV strains can also inhibit hRIG-I at variable degrees of efficiency. Collectively, our results confirm that Z proteins of pathogenic LASV and LCMV can inhibit hRIG-I and suggest that strain variations of the Z proteins can influence their efficiency to suppress host innate immunity that might contribute to viral virulence and disease heterogeneity.
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Affiliation(s)
| | | | | | | | - Yuying Liang
- Correspondence: ; Tel.: +1-612-625-3376; Fax: +1-612-625-0204
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18
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Reverse genetics approaches for the development of bunyavirus vaccines. Curr Opin Virol 2020; 44:16-25. [PMID: 32619950 DOI: 10.1016/j.coviro.2020.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022]
Abstract
The Bunyavirales order is the largest group of RNA viruses, which includes important human and animal pathogens, that cause serious diseases. Licensed vaccines are often not available for many of these pathogens. The establishment of bunyavirus reverse genetics systems has facilitated the generation of recombinant infectious viruses, which have been employed as powerful tools for understanding bunyavirus biology and identifying important virulence factors. Technological advances in this area have enabled the development of novel strategies, including codon-deoptimization, viral genome rearrangement and single-cycle replicable viruses, for the generation of live-attenuated vaccine candidates. In this review, we have summarized the current knowledge of the bunyavirus reverse genetics approaches for the generation of live-attenuated vaccine candidates and their evaluation in animal models.
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19
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Asogun DA, Günther S, Akpede GO, Ihekweazu C, Zumla A. Lassa Fever: Epidemiology, Clinical Features, Diagnosis, Management and Prevention. Infect Dis Clin North Am 2020; 33:933-951. [PMID: 31668199 DOI: 10.1016/j.idc.2019.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Lassa fever outbreaks West Africa have caused up to 10,000 deaths annually. Primary infection occurs from contact with Lassa virus-infected rodents and exposure to their excreta, blood, or meat. Incubation takes 2 to 21 days. Symptoms are difficult to distinguish from malaria, typhoid, dengue, yellow fever, and other viral hemorrhagic fevers. Clinical manifestations range from asymptomatic, to mild, to severe fulminant disease. Ribavirin can improve outcomes. Overall mortality is between 1% and 15%. Lassa fever should be considered in the differential diagnosis with travel to West Africa. There is an urgent need for rapid field-friendly diagnostics and preventive vaccine.
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Affiliation(s)
- Danny A Asogun
- Department of Public Health, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria; Department of Public Health, Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, P.M.B 008, Kilometre 87, Benin City-Auchi Road, Irrua, Nigeria.
| | - Stephan Günther
- Bernhard-Nocht Institute for Tropical Medicine, Strab 74, Hamburg 20359, Germany; German Centre for Infection Research (DZIF), Partner Site Hamburg, Hamburg, Germany
| | - George O Akpede
- Department of Paediatrics, Faculty of Clinical Sciences, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria
| | - Chikwe Ihekweazu
- Nigeria Centre for Disease Control, Plot 801, Ebitu Ukiwe Street, Jabi, Abuja, Nigeria
| | - Alimuddin Zumla
- Center for Clinical Microbiology, University College London, Royal Free Campus 2nd Floor, Rowland Hill Street, London NW3 2PF, United Kingdom
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20
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Biological Characterization of Conserved Residues within the Cytoplasmic Tail of the Pichinde Arenaviral Glycoprotein Subunit 2 (GP2). J Virol 2019; 93:JVI.01277-19. [PMID: 31462569 DOI: 10.1128/jvi.01277-19] [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: 08/09/2019] [Accepted: 08/20/2019] [Indexed: 12/13/2022] Open
Abstract
Several mammarenaviruses can cause deadly hemorrhagic fever infections in humans, with limited preventative and therapeutic measures available. Arenavirus cell entry is mediated by the viral glycoprotein (GP) complex, which consists of the stable signal peptide (SSP), the receptor-binding subunit GP1, and the transmembrane subunit GP2. The GP2 cytoplasmic tail (CT) is relatively conserved among arenaviruses and is known to interact with the SSP to regulate GP processing and membrane fusion, but its biological role in the context of an infectious virus has not been fully characterized. Using a Pichinde virus (PICV) GP expression vector and a PICV reverse genetics system, we systematically characterized the functional roles of 12 conserved residues within the GP2 CT in GP processing, trafficking, assembly, and fusion, as well as in viral replication. Except for P478A and K505A R508A, alanine substitutions at conserved residues abolished GP processing and membrane fusion in plasmid-transfected cells. Six invariant H and C residues and W503 are essential for viral replication, as evidenced by the fact that their mutant viruses could not be rescued. Both P480A and R482A mutant viruses were rescued, grew similarly to wild-type (WT) virus, and produced evidently processed GP1 and GP2 subunits in virus-infected cells, despite the fact that the same mutations abolished GP processing and membrane fusion in a plasmid-based protein expression system, illustrating the importance of using an infectious-virus system for analyzing viral glycoprotein function. In summary, our results demonstrate an essential biological role of the GP2 CT in arenavirus replication and suggest it as a potential novel target for developing antivirals and/or attenuated viral vaccine candidates.IMPORTANCE Several arenaviruses, such as Lassa virus (LASV), can cause severe and lethal hemorrhagic fever diseases with high mortality and morbidity, for which no FDA-approved vaccines or therapeutics are available. Viral entry is mediated by the arenavirus GP complex, which consists of the stable signal peptide (SSP), the receptor-binding subunit GP1, and the transmembrane subunit GP2. The cytoplasmic tail (CT) of GP2 is highly conserved among arenaviruses, but its functional role in viral replication is not completely understood. Using a reverse genetics system of a prototypic arenavirus, Pichinde virus (PICV), we show that the GP2 CT contains certain conserved residues that are essential for virus replication, implicating it as a potentially good target for developing antivirals and live-attenuated viral vaccines against deadly arenavirus pathogens.
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21
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Comparison of the Innate Immune Responses to Pathogenic and Nonpathogenic Clade B New World Arenaviruses. J Virol 2019; 93:JVI.00148-19. [PMID: 31270228 DOI: 10.1128/jvi.00148-19] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 06/28/2019] [Indexed: 12/25/2022] Open
Abstract
The New World (NW) arenaviruses are a diverse group of zoonotic viruses, including several causative agents of severe hemorrhagic fevers in humans. All known human-pathogenic NW arenaviruses belong to clade B, where they group into sublineages with phylogenetically closely related nonpathogenic viruses, e.g., the highly pathogenic Junin (JUNV) and Machupo viruses with the nonpathogenic Tacaribe virus (TCRV). Considering the close genetic relationship of nonpathogenic and pathogenic NW arenaviruses, the identification of molecular determinants of virulence is of great importance. The host cell's innate antiviral defense represents a major barrier for zoonotic infection. Here, we performed a side-by-side comparison of the innate immune responses against JUNV and TCRV in human cells. Despite similar levels of viral replication, infection with TCRV consistently induced a stronger type I interferon (IFN-I) response than JUNV infection did. Transcriptome profiling revealed upregulation of a largely overlapping set of interferon-stimulated genes in cells infected with TCRV and JUNV. Both viruses were relatively insensitive to IFN-I treatment of human cells and induced similar levels of apoptosis in the presence or absence of an IFN-I response. However, in comparison to JUNV, TCRV induced stronger activation of the innate sensor double-strand RNA-dependent protein kinase R (PKR), resulting in phosphorylation of eukaryotic translation initiation factor eIF2α. Confocal microscopy studies revealed similar subcellular colocalizations of the JUNV and TCRV viral replication-transcription complexes with PKR. However, deletion of PKR by CRISPR/Cas9 hardly affected JUNV but promoted TCRV multiplication, providing the first evidence for differential innate recognition and control of pathogenic and nonpathogenic NW arenaviruses by PKR.IMPORTANCE New World (NW) arenaviruses are a diverse family of emerging zoonotic viruses that merit significant attention as important public health problems. The close genetic relationship of nonpathogenic NW arenaviruses with their highly pathogenic cousins suggests that few mutations may be sufficient to enhance virulence. The identification of molecular determinants of virulence of NW arenaviruses is therefore of great importance. Here we undertook a side-by-side comparison of the innate immune responses against the highly pathogenic Junin virus (JUNV) and the related nonpathogenic Tacaribe virus (TCRV) in human cells. We consistently found that TCRV induces a stronger type I interferon (IFN-I) response than JUNV. Transcriptome profiling revealed an overlapping pattern of IFN-induced gene expression and similar low sensitivities to IFN-I treatment. However, the double-stranded RNA (dsRNA)-dependent protein kinase R (PKR) contributed to the control of TCRV, but not JUNV, providing the first evidence for differential innate recognition and control of JUNV and TCRV.
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A Single Dose of Modified Vaccinia Ankara Expressing Lassa Virus-like Particles Protects Mice from Lethal Intra-cerebral Virus Challenge. Pathogens 2019; 8:pathogens8030133. [PMID: 31466243 PMCID: PMC6789566 DOI: 10.3390/pathogens8030133] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/23/2019] [Accepted: 08/25/2019] [Indexed: 12/13/2022] Open
Abstract
Lassa fever surpasses Ebola, Marburg, and all other hemorrhagic fevers except Dengue in its public health impact. Caused by Lassa virus (LASV), the disease is a scourge on populations in endemic areas of West Africa, where reported incidence is higher. Here, we report construction, characterization, and preclinical efficacy of a novel recombinant vaccine candidate GEO-LM01. Constructed in the Modified Vaccinia Ankara (MVA) vector, GEO-LM01 expresses the glycoprotein precursor (GPC) and zinc-binding matrix protein (Z) from the prototype Josiah strain lineage IV. When expressed together, GP and Z form Virus-Like Particles (VLPs) in cell culture. Immunogenicity and efficacy of GEO-LM01 was tested in a mouse challenge model. A single intramuscular dose of GEO-LM01 protected 100% of CBA/J mice challenged with a lethal dose of ML29, a Mopeia/Lassa reassortant virus, delivered directly into the brain. In contrast, all control animals died within one week. The vaccine induced low levels of antibodies but Lassa-specific CD4+ and CD8+ T cell responses. This is the first report showing that a single dose of a replication-deficient MVA vector can confer full protection against a lethal challenge with ML29 virus.
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23
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[Arenavirus research and antiviral candidate]. Uirusu 2019; 68:51-62. [PMID: 31105135 DOI: 10.2222/jsv.68.51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Arenavirus is a genetic term for viruses belonging to the family Arenaviridae and is presented from lymphocytic choriomeningitis virus (LCMV), which shows almost no pathogenicity to humans, to Lassa virus, Junin virus, Machupo virus, Chapare virus, Lujo virus, Sabia virus, and Guanarito virus, which shows high pathogenicity to humans. These viruses except for LCMV are risk group 4 pathogens specified by World Health Organization. Based on this designation, it is designated as Class I pathogens in Japan. Although there have been no reports excluding one imported case of the Lassa fever patient, it is not surprising whenever imported cases occur in our country. Considering the disease severity and mortality rate, it is an urgent matter to develop vaccines and therapeutic drugs in endemic areas, and maintenances of these are also important in countries other than endemic areas. However, basic research on highly pathogenic arenavirus infections and development of therapeutic drugs are not easily progressed, because handling in highly safe research facilities is indispensable. In this article, we will outline the current knowledge from the recent basic research on arenavirus to the development situation of antivirals against arenaviruses.
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24
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Brisse ME, Ly H. Hemorrhagic Fever-Causing Arenaviruses: Lethal Pathogens and Potent Immune Suppressors. Front Immunol 2019; 10:372. [PMID: 30918506 PMCID: PMC6424867 DOI: 10.3389/fimmu.2019.00372] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/14/2019] [Indexed: 12/22/2022] Open
Abstract
Hemorrhagic fevers (HF) resulting from pathogenic arenaviral infections have traditionally been neglected as tropical diseases primarily affecting African and South American regions. There are currently no FDA-approved vaccines for arenaviruses, and treatments have been limited to supportive therapy and use of non-specific nucleoside analogs, such as Ribavirin. Outbreaks of arenaviral infections have been limited to certain geographic areas that are endemic but known cases of exportation of arenaviruses from endemic regions and socioeconomic challenges for local control of rodent reservoirs raise serious concerns about the potential for larger outbreaks in the future. This review synthesizes current knowledge about arenaviral evolution, ecology, transmission patterns, life cycle, modulation of host immunity, disease pathogenesis, as well as discusses recent development of preventative and therapeutic pursuits against this group of deadly viral pathogens.
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Affiliation(s)
- Morgan E Brisse
- Biochemistry, Molecular Biology, and Biophysics Graduate Program, University of Minnesota, St. Paul, MN, United States.,Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, United States
| | - Hinh Ly
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, United States
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25
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Loureiro ME, D'Antuono A, López N. Virus⁻Host Interactions Involved in Lassa Virus Entry and Genome Replication. Pathogens 2019; 8:pathogens8010017. [PMID: 30699976 PMCID: PMC6470645 DOI: 10.3390/pathogens8010017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/25/2019] [Accepted: 01/26/2019] [Indexed: 01/08/2023] Open
Abstract
Lassa virus (LASV) is the causative agent of Lassa fever, a human hemorrhagic disease associated with high mortality and morbidity rates, particularly prevalent in West Africa. Over the past few years, a significant amount of novel information has been provided on cellular factors that are determinant elements playing a role in arenavirus multiplication. In this review, we focus on host proteins that intersect with the initial steps of the LASV replication cycle: virus entry and genome replication. A better understanding of relevant virus⁻host interactions essential for sustaining these critical steps may help to identify possible targets for the rational design of novel therapeutic approaches against LASV and other arenaviruses that cause severe human disease.
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Affiliation(s)
- María Eugenia Loureiro
- Centro de Virología Animal (CEVAN), CONICET-SENASA, Av Sir Alexander Fleming 1653, Martínez, Provincia de Buenos Aires B1640CSI, Argentina.
| | - Alejandra D'Antuono
- Centro de Virología Animal (CEVAN), CONICET-SENASA, Av Sir Alexander Fleming 1653, Martínez, Provincia de Buenos Aires B1640CSI, Argentina.
| | - Nora López
- Centro de Virología Animal (CEVAN), CONICET-SENASA, Av Sir Alexander Fleming 1653, Martínez, Provincia de Buenos Aires B1640CSI, Argentina.
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26
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Schaeffer J, Carnec X, Reynard S, Mateo M, Picard C, Pietrosemoli N, Dillies MA, Baize S. Lassa virus activates myeloid dendritic cells but suppresses their ability to stimulate T cells. PLoS Pathog 2018; 14:e1007430. [PMID: 30419076 PMCID: PMC6258464 DOI: 10.1371/journal.ppat.1007430] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 11/26/2018] [Accepted: 10/23/2018] [Indexed: 01/09/2023] Open
Abstract
Lassa virus (LASV) is responsible for a viral hemorrhagic fever in humans and the death of 3,000 to 5,000 people every year. The immune response to LASV is poorly understood, but type I interferon (IFN-I) and T-cell responses appear to be critical for the host. We studied the response of myeloid dendritic cells (mDC) to LASV, as mDCs are involved in both IFN-I production and T-cell activation. We compared the response of primary human mDCs to LASV and Mopeia virus (MOPV), which is similar to LASV, but non-pathogenic. We showed that mDCs produced substantial amounts of IFN-I in response to both LASV and MOPV. However, only MOPV-infected mDCs were able to activate T cells. More surprisingly, coculture with T cells completely inhibited the activation of LASV-infected mDCs. These differences between LASV and MOPV were mostly due to the LASV nucleoprotein, which has major immunosuppressive properties, but the glycoprotein was also involved. Overall, these results suggest that mDCs may be important for the global response to LASV and play a role in the outcome of Lassa fever. Lassa fever is a viral hemorrhagic fever and a major public health issue in West Africa. Lassa virus, the causative agent of Lassa fever, is listed by the World Health Organization as one of the emerging pathogens likely to cause severe outbreaks in the near future. Indeed, there is currently no vaccine and no treatment against Lassa virus. Determinants of Lassa virus high pathogenicity are not completely understood. However, it has been shown that rapid type I interferon response and efficient T cell response were critical to survive Lassa fever. Dendritic cells are at the crossroads of innate and adaptive immunity. Their direct response to viral infection includes type I interferon production. They can also present viral antigens, initiating the T cell responses. We decided to investigate how dendritic cells respond to Lassa virus to evaluate their importance in the global immune response. We showed that primary human myeloid dendritic cells are activated by Lassa virus infection, and produce type I interferon. However, Lassa virus-infected dendritic cells were not able to activate T cells. We also elucidated the roles of viral proteins in the modulation of dendritic cell responses.
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Affiliation(s)
- Justine Schaeffer
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Xavier Carnec
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Stéphanie Reynard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Mathieu Mateo
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Caroline Picard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Natalia Pietrosemoli
- Bioinformatics and Biostatistics Hub, Centre de Bioinformatique Biostatistique et Biologie Intégrative (C3BI, USR 3756, IP CNRS), Institut Pasteur, Paris, France
| | - Marie-Agnès Dillies
- Bioinformatics and Biostatistics Hub, Centre de Bioinformatique Biostatistique et Biologie Intégrative (C3BI, USR 3756, IP CNRS), Institut Pasteur, Paris, France
| | - Sylvain Baize
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur; Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
- * E-mail:
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27
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Tang K, He S, Zhang X, Guo J, Chen Q, Yan F, Banadyga L, Zhu W, Qiu X, Guo Y. Tangeretin, an extract from Citrus peels, blocks cellular entry of arenaviruses that cause viral hemorrhagic fever. Antiviral Res 2018; 160:87-93. [PMID: 30339847 DOI: 10.1016/j.antiviral.2018.10.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/03/2018] [Accepted: 10/09/2018] [Indexed: 11/16/2022]
Abstract
The family Arenaviridae consists of numerous enveloped RNA viruses with ambisense coding strategies. Eight arenaviruses, including Lassa virus, are known to cause severe and fatal viral hemorrhagic fever (VHF) in humans, yet vaccines and treatments for disease caused by arenaviruses are very limited. In this study, we screened a natural product library consisting of 131 compounds and identified tangeretin, a polymethoxylated flavone widely present in citrus fruit peels, as a Lassa virus entry inhibitor that blocks viral fusion. Further analyses demonstrated the efficacy of tangeretin against seven other VHF-causing arenaviruses, suggesting that this compound, which has a history of medical usage, could be used to develop an effective therapeutic to treat infection and disease caused by Lassa virus and related viruses.
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Affiliation(s)
- Ke Tang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Shihua He
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, R3E 3R2, Canada
| | - Xiaoyu Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Jiamei Guo
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Qing Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Feihu Yan
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, R3E 3R2, Canada; Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, R3E 0J9, Canada; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Science, Changchun, 130122, China
| | - Logan Banadyga
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, R3E 3R2, Canada
| | - Wenjun Zhu
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, R3E 3R2, Canada
| | - Xiangguo Qiu
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, R3E 3R2, Canada; Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, R3E 0J9, Canada.
| | - Ying Guo
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China.
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28
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Linero F, Sepúlveda C, Christopoulou I, Hulpiau P, Scolaro L, Saelens X. Neutralization of Junín virus by single domain antibodies targeted against the nucleoprotein. Sci Rep 2018; 8:11451. [PMID: 30061671 PMCID: PMC6065417 DOI: 10.1038/s41598-018-29508-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/11/2018] [Indexed: 01/28/2023] Open
Abstract
The syndrome viral haemorrhagic fever (VHF) designates a broad range of diseases that are caused by different viruses including members of the family Arenaviridae. Prophylaxis for Argentine Haemorrhagic Fever (AHF), caused by the arenavirus Junín (JUNV), has been achieved by the use of a live attenuated vaccine, named Candid#1. The standard treatment of AHF is transfusion of convalescent human plasma. Our aim was to develop an alternative and safer treatment for AHF based on the use of virus-neutralizing single domain antibodies (VHHs). We describe the first reported VHHs directed against an arenavirus. These VHHs could neutralize Candid#1 by altering virion binding/fusion. Surprisingly, the neutralizing VHHs appeared to be specific for the viral nucleoprotein (N) that is not known to be involved in arenavirus entry. Candid#1 VHH-escape viruses had acquired a predicted N-glycosylation site in the surface glycoprotein GP1 that is present in highly pathogenic JUNV strains. Accordingly, the Candid#1-neutralizing VHHs could not neutralize pathogenic JUNV strains, but they could still bind to cells infected with a pathogenic strain or the escape mutant viruses. These results show that the attenuated strains of JUNV can be potently neutralized by nucleoprotein-specific VHHs.
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Affiliation(s)
- Florencia Linero
- VIB Center for Medical Biotechnology, Ghent, B-9052, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, B-9052, Belgium
| | - Claudia Sepúlveda
- Laboratory of Virology, Faculty of Sciences, University of Buenos Aires, C1428EGA, Caba, Argentina
| | - Ioanna Christopoulou
- VIB Center for Medical Biotechnology, Ghent, B-9052, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, B-9052, Belgium
| | - Paco Hulpiau
- Department of Biomedical Molecular Biology, Ghent University, Ghent, B-9052, Belgium.,VIB Center for Inflammation Research, VIB, Ghent, B-9052, Belgium
| | - Luis Scolaro
- Laboratory of Virology, Faculty of Sciences, University of Buenos Aires, C1428EGA, Caba, Argentina
| | - Xavier Saelens
- VIB Center for Medical Biotechnology, Ghent, B-9052, Belgium. .,Department of Biomedical Molecular Biology, Ghent University, Ghent, B-9052, Belgium.
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29
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Han Z, Schwoerer MP, Hicks P, Liang J, Ruthel G, Berry CT, Freedman BD, Sagum CA, Bedford MT, Sidhu SS, Sudol M, Harty RN. Host Protein BAG3 is a Negative Regulator of Lassa VLP Egress. Diseases 2018; 6:diseases6030064. [PMID: 30011814 PMCID: PMC6163595 DOI: 10.3390/diseases6030064] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/10/2018] [Accepted: 07/12/2018] [Indexed: 12/20/2022] Open
Abstract
Lassa fever virus (LFV) belongs to the Arenaviridae family and can cause acute hemorrhagic fever in humans. The LFV Z protein plays a central role in virion assembly and egress, such that independent expression of LFV Z leads to the production of virus-like particles (VLPs) that mimic egress of infectious virus. LFV Z contains both PTAP and PPPY L-domain motifs that are known to recruit host proteins that are important for mediating efficient virus egress and spread. The viral PPPY motif is known to interact with specific host WW-domain bearing proteins. Here we identified host WW-domain bearing protein BCL2 Associated Athanogene 3 (BAG3) as a LFV Z PPPY interactor using our proline-rich reading array of WW-domain containing mammalian proteins. BAG3 is a stress-induced molecular co-chaperone that functions to regulate cellular protein homeostasis and cell survival via Chaperone-Assisted Selective Autophagy (CASA). Similar to our previously published findings for the VP40 proteins of Ebola and Marburg viruses, our results using VLP budding assays, BAG3 knockout cells, and confocal microscopy indicate that BAG3 is a WW-domain interactor that negatively regulates egress of LFV Z VLPs, rather than promoting VLP release. Our results suggest that CASA and specifically BAG3 may represent a novel host defense mechanism, whereby BAG3 may dampen egress of several hemorrhagic fever viruses by interacting and interfering with the budding function of viral PPxY-containing matrix proteins.
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Affiliation(s)
- Ziying Han
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Michael P Schwoerer
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Philip Hicks
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Jingjing Liang
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Gordon Ruthel
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Corbett T Berry
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Bruce D Freedman
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Cari A Sagum
- Department of Epigenetics & Molecular Carcinogenesis, M.D. Anderson Cancer Center, University of Texas, Smithville, TX 78957, USA.
| | - Mark T Bedford
- Department of Epigenetics & Molecular Carcinogenesis, M.D. Anderson Cancer Center, University of Texas, Smithville, TX 78957, USA.
| | - Sachdev S Sidhu
- Department of Molecular Genetics, University of Toronto, Toronto, ON M1C 1A4, Canada.
| | - Marius Sudol
- Department of Physiology, Institute for Molecular and Cell Biology (IMCB, AStar), National University of Singapore, Singapore 119077, Singapore.
| | - Ronald N Harty
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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30
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Fernandes J, Guterres A, de Oliveira RC, Chamberlain J, Lewandowski K, Teixeira BR, Coelho TA, Crisóstomo CF, Bonvicino CR, D'Andrea PS, Hewson R, de Lemos ERS. Xapuri virus, a novel mammarenavirus: natural reassortment and increased diversity between New World viruses. Emerg Microbes Infect 2018; 7:120. [PMID: 29959319 PMCID: PMC6026159 DOI: 10.1038/s41426-018-0119-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/21/2018] [Accepted: 05/27/2018] [Indexed: 12/28/2022]
Abstract
Mammarenavirus RNA was detected in Musser’s bristly mouse (Neacomys musseri) from the Amazon region, and this detection indicated that rodents were infected with a novel mammarenavirus, with the proposed name Xapuri virus (XAPV), which is phylogenetically related to New World Clade B and Clade C viruses. XAPV may represent the first natural reassortment of the Arenaviridae family and a new unrecognized clade within the Tacaribe serocomplex group.
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Affiliation(s)
- Jorlan Fernandes
- Laboratory of Hantaviruses and Rickettsiosis, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil.
| | - Alexandro Guterres
- Laboratory of Hantaviruses and Rickettsiosis, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - Renata Carvalho de Oliveira
- Laboratory of Hantaviruses and Rickettsiosis, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - John Chamberlain
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, SP4 0JG, UK
| | - Kuiama Lewandowski
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, SP4 0JG, UK
| | - Bernardo Rodrigues Teixeira
- Laboratory of Biology and Parasitology of Wild Mammals Reservoirs, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - Thayssa Alves Coelho
- Laboratory of Hantaviruses and Rickettsiosis, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - Charle Ferreira Crisóstomo
- Laboratory of Biology and Parasitology of Wild Mammals Reservoirs, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil.,Federal Institute of Acre, Rio Branco - AC, 69900-640, Brazil.,Postgraduate Program in Biodiversity and Health, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - Cibele Rodrigues Bonvicino
- Laboratory of Biology and Parasitology of Wild Mammals Reservoirs, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil.,Nacional Cancer Institute, Rio de Janeio - RJ, 20230-130, Brazil
| | - Paulo Sérgio D'Andrea
- Laboratory of Biology and Parasitology of Wild Mammals Reservoirs, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil.,Postgraduate Program in Biodiversity and Health, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil
| | - Roger Hewson
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, SP4 0JG, UK
| | - Elba Regina Sampaio de Lemos
- Laboratory of Hantaviruses and Rickettsiosis, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro - RJ, 21040-360, Brazil.
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31
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Antibodies to the Glycoprotein GP2 Subunit Cross-React between Old and New World Arenaviruses. mSphere 2018; 3:3/3/e00189-18. [PMID: 29720525 PMCID: PMC5932378 DOI: 10.1128/msphere.00189-18] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 04/11/2018] [Indexed: 12/15/2022] Open
Abstract
Arenaviruses pose a major public health threat and cause numerous infections in humans each year. Although most viruses belonging to this family do not cause disease in humans, some arenaviruses, such as Lassa virus and Machupo virus, are the etiological agents of lethal hemorrhagic fevers. The absence of a currently licensed vaccine and the highly pathogenic nature of these viruses both make the necessity of developing viable vaccines and therapeutics all the more urgent. Arenaviruses have a single glycoprotein on the surface of virions, the glycoprotein complex (GPC), and this protein can be used as a target for vaccine development. Here, we describe immunization strategies to generate monoclonal antibodies (MAbs) that cross-react between the glycoprotein complexes of both Old World and New World arenaviruses. Several monoclonal antibodies isolated from immunized mice were highly cross-reactive, binding a range of Old World arenavirus glycoproteins, including that of Lassa virus. One such monoclonal antibody, KL-AV-2A1, bound to GPCs of both New World and Old World viruses, including Lassa and Machupo viruses. These cross-reactive antibodies bound to epitopes present on the glycoprotein 2 subunit of the glycoprotein complex, which is relatively conserved among arenaviruses. Monoclonal antibodies binding to these epitopes, however, did not inhibit viral entry as they failed to neutralize a replication-competent vesicular stomatitis virus pseudotyped with the Lassa virus glycoprotein complex in vitro In addition, no protection from virus challenge was observed in in vivo mouse models. Even so, these monoclonal antibodies might still prove to be useful in the development of clinical and diagnostic assays.IMPORTANCE Several viruses in the Arenaviridae family infect humans and cause severe hemorrhagic fevers which lead to high case fatality rates. Due to their pathogenicity and geographic tropisms, these viruses remain very understudied. As a result, an effective vaccine or therapy is urgently needed. Here, we describe efforts to produce cross-reactive monoclonal antibodies that bind to both New and Old World arenaviruses. All of our MAbs seem to be nonneutralizing and nonprotective and target subunit 2 of the glycoprotein. Due to the lack of reagents such as recombinant glycoproteins and antibodies for rapid detection assays, our MAbs could be beneficial as analytic and diagnostic tools.
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32
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Zaza AD, Herbreteau CH, Peyrefitte CN, Emonet SF. Mammarenaviruses deleted from their Z gene are replicative and produce an infectious progeny in BHK-21 cells. Virology 2018; 518:34-44. [PMID: 29453057 DOI: 10.1016/j.virol.2018.01.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/16/2018] [Accepted: 01/18/2018] [Indexed: 11/19/2022]
Abstract
Mammarenaviruses bud out of infected cells via the recruitment of the endosomal sorting complex required for transport through late domain motifs localized into their Z protein. Here, we demonstrated that mammarenaviruses lacking this protein can be rescued and are replicative, despite a 3-log reduction in virion production, in BHK-21 cells, but not in five other cell lines. Mutations of putative late domain motifs identified into the viral nucleoprotein resulted in the almost complete abolition of infectious virion production by Z-deleted mammarenaviruses. This result strongly suggested that the nucleoprotein may compensate for the deletion of Z. These observations were primarily obtained using the Lymphocytic choriomeningitis virus, and further confirmed using the Old World Lassa and New World Machupo viruses, responsible of human hemorrhagic fevers. Z-deleted viruses should prove very useful tools to investigate the biology of Mammarenaviruses.
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Affiliation(s)
- Amélie D Zaza
- Fab'entech, 24 rue Jean Baldassini, 69007 Lyon, France; Unité de virologie, Département de Biologie des Agents Transmissibles, Institut de Recherche Biomédicale des Armées, 1 place général Valérie André, BP 73 91 223 Brétigny-sur-Orge cedex, France.
| | | | - Christophe N Peyrefitte
- Unité de virologie, Département de Biologie des Agents Transmissibles, Institut de Recherche Biomédicale des Armées, 1 place général Valérie André, BP 73 91 223 Brétigny-sur-Orge cedex, France.
| | - Sébastien F Emonet
- Unité de virologie, Département de Biologie des Agents Transmissibles, Institut de Recherche Biomédicale des Armées, 1 place général Valérie André, BP 73 91 223 Brétigny-sur-Orge cedex, France.
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33
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Wingerath J, Ostroumov D, Woller N, Manns MP, Pinschewer DD, Orlinger K, Berka U, Kühnel F, Wirth TC. Recombinant LCMV Vectors Induce Protective Immunity following Homologous and Heterologous Vaccinations. Mol Ther 2017; 25:2533-2545. [PMID: 28803862 DOI: 10.1016/j.ymthe.2017.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 07/11/2017] [Accepted: 07/16/2017] [Indexed: 01/15/2023] Open
Abstract
Successful vaccination against cancer and infectious diseases relies on the induction of adaptive immune responses that induce high-titer antibodies or potent cytoxic T cell responses. In contrast to humoral vaccines, the amplification of cellular immune responses is often hampered by anti-vector immunity that either pre-exists or develops after repeated homologous vaccination. Replication-defective lymphocytic choriomeningitis virus (LCMV) vectors represent a novel generation of vaccination vectors that induce potent immune responses while escaping recognition by neutralizing antibodies. Here, we characterize the CD8 T cell immune response induced by replication-defective recombinant LCMV (rLCMV) vectors with regard to expansion kinetics, trafficking, phenotype, and function and we perform head-to-head comparisons of the novel rLCMV vectors with established vectors derived from adenovirus, vaccinia virus, or Listeria monocytogenes. Our results demonstrate that replication-deficient rLCMV vectors are safe and ideally suited for both homologous and heterologous vaccination regimens to achieve optimal amplification of CD8 T cell immune responses in vivo.
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Affiliation(s)
- Jessica Wingerath
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Dmitrij Ostroumov
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Norman Woller
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Michael P Manns
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Daniel D Pinschewer
- Division of Experimental Virology, Department of Biomedicine, University of Basel, 4051 Basel, Switzerland
| | - Klaus Orlinger
- Hookipa Biotech AG, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
| | - Ursula Berka
- Hookipa Biotech AG, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
| | - Florian Kühnel
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Thomas C Wirth
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany.
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34
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Abstract
Hemorrhagic fevers caused by viruses were identified in the late 1950s in South America. These viruses have existed in their hosts, the New World rodents, for millions of years. Their emergence as infectious agents in humans coincided with changes in the environment and farming practices that caused explosions in their host rodent populations. Zoonosis into humans likely occurs because the pathogenic New World arenaviruses use human transferrin receptor 1 to enter cells. The mortality rate after infection with these viruses is high, but the mechanism by which disease is induced is still not clear. Possibilities include direct effects of cellular infection or the induction of high levels of cytokines by infected sentinel cells of the immune system, leading to endothelia and thrombocyte dysfunction and neurological disease. Here we provide a review of the ecology and molecular and cellular biology of New World arenaviruses, as well as a discussion of the current animal models of infection. The development of animal models, coupled with an improved understanding of the infection pathway and host response, should lead to the discovery of new drugs for treating infections.
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Affiliation(s)
- Nicolás Sarute
- Department of Microbiology and Immunology, University of Illinois College of Medicine at Chicago, Chicago, Illinois 60612; ,
| | - Susan R Ross
- Department of Microbiology and Immunology, University of Illinois College of Medicine at Chicago, Chicago, Illinois 60612; ,
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35
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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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36
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Ly H. Virulence profile: Hinh Ly. Virulence 2016; 7:895-897. [PMID: 27414073 PMCID: PMC5160389 DOI: 10.1080/21505594.2016.1212584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Characterization of the Glycoprotein Stable Signal Peptide in Mediating Pichinde Virus Replication and Virulence. J Virol 2016; 90:10390-10397. [PMID: 27630230 DOI: 10.1128/jvi.01154-16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/02/2016] [Indexed: 11/20/2022] Open
Abstract
Arenaviruses can cause lethal hemorrhagic fevers in humans with few preventative and therapeutic measures. The arenaviral glycoprotein stable signal peptide (SSP) is unique among signal peptides in that it is an integral component of the mature glycoprotein complex (GPC) and plays important roles not only in GPC expression and processing but also in the membrane fusion process during viral entry. Using the Pichinde virus (PICV) reverse genetics system, we analyzed the effects of alanine substitutions at many conserved residues within the SSP on viral replication in cell culture and in a guinea pig infection model. Our data showed that the K33A, F49A, and C57A mutations abolished GPC-mediated cell entry and therefore could not allow for the generation of viable recombinant viruses, demonstrating that these residues are essential for the PICV life cycle. The G2A mutation caused a marked reduction of cell entry at the membrane fusion step, and while this mutant virus was viable, it was significantly attenuated in vitro and in vivo The N20A mutation also reduced membrane fusion activity and viral virulence in guinea pigs, but it did not significantly affect cell entry or viral growth in cell culture. Two other mutations (N37A and R55A) did not affect membrane fusion or viral growth in vitro but significantly reduced viral virulence in vivo Taken together, our data suggest that the GPC SSP plays an essential role in mediating viral entry and also contributes to viral virulence in vivo IMPORTANCE: Several arenaviruses, such as Lassa fever virus, can cause severe and lethal hemorrhagic fever diseases with high mortality and morbidity, and no FDA-approved vaccines or therapies are currently available. Viral entry into cells is mediated by arenavirus GPC that consists of an SSP, the receptor-binding GP1, and transmembrane GP2 protein subunits. Using a reverse genetics system of a prototypic arenavirus, Pichinde virus (PICV), we have shown for the first time in the context of virus infections of cell culture and of guinea pigs that the SSP plays an essential role in mediating the membrane fusion step as well as in other yet-to-be-determined processes during viral infection. Our study provides important insights into the biological roles of GPC SSP and implicates it as a good target for the development of antivirals against deadly human arenavirus pathogens.
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Hilpert C, Sitte S, Matthies A, Voehringer D. Dendritic Cells Are Dispensable for T Cell Priming and Control of Acute Lymphocytic Choriomeningitis Virus Infection. THE JOURNAL OF IMMUNOLOGY 2016; 197:2780-6. [PMID: 27549169 DOI: 10.4049/jimmunol.1502582] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 07/22/2016] [Indexed: 11/19/2022]
Abstract
Dendritic cells (DCs) are considered to be the major APCs with potent activity for priming of naive CD4 and CD8 T cells. However, T cell priming can also be achieved by other APCs including macrophages, B cells, or even nonhematopoietic cell types. Systemic low-dose infection of mice with lymphocytic choriomeningitis virus (LCMV) results in massive expansion of virus-specific CD4 and CD8 T cells. To determine the role of DCs as APCs and source of type I IFNs in this infection model, we used ΔDC mice in which DCs are constitutively ablated because of expression of the diphtheria toxin α subunit within developing DCs. ΔDC mice showed lower serum concentrations of IFN-β and IL-12p40, but normal IFN-α levels during the first days postinfection. No differences were found for proliferation of transferred TCR-transgenic cells during the early phase of infection, suggesting that T cell priming occurred with the same efficiency in wild-type and ΔDC mice. Expansion and cytokine expression of endogenous LCMV-specific T cells was comparable between wild-type and ΔDC mice during primary infection and upon rechallenge of memory mice. In both strains of infected mice the viral load was reduced below the limit of detection with the same kinetic. Further, germinal center formation and LCMV-specific Ab responses were not impaired in ΔDC mice. This indicates that DCs are dispensable as APCs for protective immunity against LCMV infection.
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Affiliation(s)
- Cornelia Hilpert
- Department of Infection Biology, University Hospital Erlangen and Friedrich Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Selina Sitte
- Department of Infection Biology, University Hospital Erlangen and Friedrich Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Alexander Matthies
- Department of Infection Biology, University Hospital Erlangen and Friedrich Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - David Voehringer
- Department of Infection Biology, University Hospital Erlangen and Friedrich Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
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Native functionality and therapeutic targeting of arenaviral glycoproteins. Curr Opin Virol 2016; 18:70-5. [PMID: 27104809 DOI: 10.1016/j.coviro.2016.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 03/08/2016] [Accepted: 04/01/2016] [Indexed: 12/31/2022]
Abstract
Surface glycoproteins direct cellular targeting, attachment, and membrane fusion of arenaviruses and are the primary target for neutralizing antibodies. Despite significant conservation of the glycoprotein architecture across the arenavirus family, there is considerable variation in the molecular recognition mechanisms used during host cell entry. We review recent progress in dissecting these infection events and describe how arenaviral glycoproteins can be targeted by small-molecule antivirals, the natural immune response, and immunoglobulin-based therapeutics. Arenaviral glycoprotein-mediated assembly and infection pathways present numerous opportunities and challenges for therapeutic intervention.
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Meyer B, Ly H. Immunosuppressive arenaviral exoribonuclease. Oncotarget 2015; 6:32315-6. [PMID: 26468986 PMCID: PMC4741695 DOI: 10.18632/oncotarget.6110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 10/13/2015] [Indexed: 11/29/2022] Open
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