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Chew BLA, Ngoh ANQ, Phoo WW, Chan KWK, Ser Z, Tulsian NK, Lim SS, Weng MJG, Watanabe S, Choy MM, Low J, Ooi EE, Ruedl C, Sobota RM, Vasudevan SG, Luo D. Secreted dengue virus NS1 from infection is predominantly dimeric and in complex with high-density lipoprotein. eLife 2024; 12:RP90762. [PMID: 38787378 PMCID: PMC11126310 DOI: 10.7554/elife.90762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024] Open
Abstract
Severe dengue infections are characterized by endothelial dysfunction shown to be associated with the secreted nonstructural protein 1 (sNS1), making it an attractive vaccine antigen and biotherapeutic target. To uncover the biologically relevant structure of sNS1, we obtained infection-derived sNS1 (isNS1) from dengue virus (DENV)-infected Vero cells through immunoaffinity purification instead of recombinant sNS1 (rsNS1) overexpressed in insect or mammalian cell lines. We found that isNS1 appeared as an approximately 250 kDa complex of NS1 and ApoA1 and further determined the cryoEM structures of isNS1 and its complex with a monoclonal antibody/Fab. Indeed, we found that the major species of isNS1 is a complex of the NS1 dimer partially embedded in a high-density lipoprotein (HDL) particle. Crosslinking mass spectrometry studies confirmed that the isNS1 interacts with the major HDL component ApoA1 through interactions that map to the NS1 wing and hydrophobic domains. Furthermore, our studies demonstrated that the sNS1 in sera from DENV-infected mice and a human patient form a similar complex as isNS1. Our results report the molecular architecture of a biological form of sNS1, which may have implications for the molecular pathogenesis of dengue.
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Affiliation(s)
- Bing Liang Alvin Chew
- Lee Kong Chian School of Medicine, Nanyang Technological UniversitySingaporeSingapore
- NTU Institute of Structural Biology, Nanyang Technological UniversitySingaporeSingapore
| | - AN Qi Ngoh
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
| | - Wint Wint Phoo
- Functional Proteomics Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology and ResearchSingaporeSingapore
| | - Kitti Wing Ki Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
| | - Zheng Ser
- Functional Proteomics Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology and ResearchSingaporeSingapore
| | - Nikhil K Tulsian
- Department of Biological Sciences, National University of SingaporeSingaporeSingapore
- Singapore Centre for Life Sciences, Department of Biochemistry, National University of SingaporeSingaporeSingapore
| | - Shiao See Lim
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
| | - Mei Jie Grace Weng
- Lee Kong Chian School of Medicine, Nanyang Technological UniversitySingaporeSingapore
- NTU Institute of Structural Biology, Nanyang Technological UniversitySingaporeSingapore
| | - Satoru Watanabe
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
| | - Milly M Choy
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
| | - Jenny Low
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
- Department of Infectious Diseases, Singapore General HospitalSingaporeSingapore
| | - Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
- Yong Loo Lin School of Medicine, National University of SingaporeSingaporeSingapore
- Saw Swee Hock School of Public Health, National University of SingaporeSingaporeSingapore
| | - Christiane Ruedl
- School of Biological Sciences, Nanyang Technological UniversitySingaporeSingapore
| | - Radoslaw M Sobota
- Functional Proteomics Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology and ResearchSingaporeSingapore
| | - Subhash G Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical SchoolSingaporeSingapore
- Department of Microbiology and Immunology, National University of SingaporeSingaporeSingapore
- Institute for Glycomics (G26), Griffith University Gold Coast CampusSouthportAustralia
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological UniversitySingaporeSingapore
- NTU Institute of Structural Biology, Nanyang Technological UniversitySingaporeSingapore
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Morales SV, Coelho GM, Ricciardi-Jorge T, Dorl GG, Zanluca C, Duarte Dos Santos CN. Development of a quantitative NS1 antigen enzyme-linked immunosorbent assay (ELISA) for Zika virus detection using a novel virus-specific mAb. Sci Rep 2024; 14:2544. [PMID: 38291109 PMCID: PMC10827715 DOI: 10.1038/s41598-024-52123-2] [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: 09/29/2023] [Accepted: 01/14/2024] [Indexed: 02/01/2024] Open
Abstract
Viruses from the Flaviviridae family, such as Dengue virus (DENV), Yellow fever virus (YFV), and Zika virus (ZIKV) are notorious global public health problems. ZIKV emergence in Polynesia and the Americas from 2013 to 2016 raised concerns as new distinguishing features set it apart from previous outbreaks, including its association with neurological complications and heightened disease severity. Virus detection is impaired as cross-reactivity to other closely related orthoflaviviruses is common among commercially available diagnostic kits. While non-structural protein 1 (NS1) has been used as an early marker of DENV and West Nile virus (WNV) infection, little is known about NS1 expression during ZIKV infection. In the present work, we developed a NS1 capture ELISA using a novel ZIKV-specific monoclonal antibody to study NS1 expression dynamics in vitro in mosquito and human cell lines. While detectable in culture supernatants, higher concentrations of NS1 were predominantly cell-associated. To our knowledge, this is the first report of NS1 detection in human cells despite viral clearance over time. Tests with human samples need to be conducted to validate the applicability of NS1 detection for diagnosis, but overall, the tools developed in this work are promising for specific detection of acute ZIKV infection.
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Affiliation(s)
| | - Gabriela Mattoso Coelho
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ, Curitiba, Paraná, Brazil
| | | | - Gisiane Gruber Dorl
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ, Curitiba, Paraná, Brazil
| | - Camila Zanluca
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ, Curitiba, Paraná, Brazil
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Perera DR, Ranadeva ND, Sirisena K, Wijesinghe KJ. Roles of NS1 Protein in Flavivirus Pathogenesis. ACS Infect Dis 2024; 10:20-56. [PMID: 38110348 DOI: 10.1021/acsinfecdis.3c00566] [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] [Indexed: 12/20/2023]
Abstract
Flaviviruses such as dengue, Zika, and West Nile viruses are highly concerning pathogens that pose significant risks to public health. The NS1 protein is conserved among flaviviruses and is synthesized as a part of the flavivirus polyprotein. It plays a critical role in viral replication, disease progression, and immune evasion. Post-translational modifications influence NS1's stability, secretion, antigenicity, and interactions with host factors. NS1 protein forms extensive interactions with host cellular proteins allowing it to affect vital processes such as RNA processing, gene expression regulation, and cellular homeostasis, which in turn influence viral replication, disease pathogenesis, and immune responses. NS1 acts as an immune evasion factor by delaying complement-dependent lysis of infected cells and contributes to disease pathogenesis by inducing endothelial cell damage and vascular leakage and triggering autoimmune responses. Anti-NS1 antibodies have been shown to cross-react with host endothelial cells and platelets, causing autoimmune destruction that is hypothesized to contribute to disease pathogenesis. However, in contrast, immunization of animal models with the NS1 protein confers protection against lethal challenges from flaviviruses such as dengue and Zika viruses. Understanding the multifaceted roles of NS1 in flavivirus pathogenesis is crucial for effective disease management and control. Therefore, further research into NS1 biology, including its host protein interactions and additional roles in disease pathology, is imperative for the development of strategies and therapeutics to combat flavivirus infections successfully. This Review provides an in-depth exploration of the current available knowledge on the multifaceted roles of the NS1 protein in the pathogenesis of flaviviruses.
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Affiliation(s)
- Dayangi R Perera
- Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka 00300
| | - Nadeeka D Ranadeva
- Department of Biomedical Science, Faculty of Health Sciences, KIU Campus Sri Lanka 10120
| | - Kavish Sirisena
- Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka 00300
- Section of Genetics, Institute for Research and Development in Health and Social Care, Sri Lanka 10120
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Alcalá AC, Ludert JE. The dengue virus NS1 protein; new roles in pathogenesis due to similarities with and affinity for the high-density lipoprotein (HDL)? PLoS Pathog 2023; 19:e1011587. [PMID: 37616216 PMCID: PMC10449462 DOI: 10.1371/journal.ppat.1011587] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/26/2023] Open
Affiliation(s)
- Ana C. Alcalá
- MU Center for Influenza and Emerging Infectious Diseases, University of Missouri, Columbia, MO, United States of America
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, United States of America
- Bond Life Science Center, University of Missouri, Columbia, MO, United States of America
| | - Juan E. Ludert
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV), Mexico City, Mexico
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Pustijanac E, Buršić M, Talapko J, Škrlec I, Meštrović T, Lišnjić D. Tick-Borne Encephalitis Virus: A Comprehensive Review of Transmission, Pathogenesis, Epidemiology, Clinical Manifestations, Diagnosis, and Prevention. Microorganisms 2023; 11:1634. [PMID: 37512806 PMCID: PMC10383662 DOI: 10.3390/microorganisms11071634] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/30/2023] Open
Abstract
Tick-borne encephalitis virus (TBEV), a member of the Flaviviridae family, can cause serious infection of the central nervous system in humans, resulting in potential neurological complications and fatal outcomes. TBEV is primarily transmitted to humans through infected tick bites, and the viral agent circulates between ticks and animals, such as deer and small mammals. The occurrence of the infection aligns with the seasonal activity of ticks. As no specific antiviral therapy exists for TBEV infection, treatment approaches primarily focus on symptomatic relief and support. Active immunization is highly effective, especially for individuals in endemic areas. The burden of TBEV infections is increasing, posing a growing health concern. Reported incidence rates rose from 0.4 to 0.9 cases per 100,000 people between 2015 and 2020. The Baltic and Central European countries have the highest incidence, but TBE is endemic across a wide geographic area. Various factors, including social and environmental aspects, improved medical awareness, and advanced diagnostics, have contributed to the observed increase. Diagnosing TBEV infection can be challenging due to the non-specific nature of the initial symptoms and potential co-infections. Accurate diagnosis is crucial for appropriate management, prevention of complications, and effective control measures. In this comprehensive review, we summarize the molecular structure of TBEV, its transmission and circulation in natural environments, the pathogenesis of TBEV infection, the epidemiology and global distribution of the virus, associated risk factors, clinical manifestations, and diagnostic approaches. By improving understanding of these aspects, we aim to enhance knowledge and promote strategies for timely and accurate diagnosis, appropriate management, and the implementation of effective control measures against TBEV infections.
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Affiliation(s)
- Emina Pustijanac
- Faculty of Natural Sciences, Juraj Dobrila University of Pula, 52100 Pula, Croatia
| | - Moira Buršić
- Faculty of Natural Sciences, Juraj Dobrila University of Pula, 52100 Pula, Croatia
| | - Jasminka Talapko
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
| | - Ivana Škrlec
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
| | - Tomislav Meštrović
- University Centre Varaždin, University North, 42000 Varaždin, Croatia
- Institute for Health Metrics and Evaluation and the Department of Health Metrics Sciences, University of Washington, Seattle, WA 98195, USA
| | - Dubravka Lišnjić
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
- Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Josipa Huttlera 4, 31000 Osijek, Croatia
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Marano JM, Weger-Lucarelli J. Replication in the presence of dengue convalescent serum impacts Zika virus neutralization sensitivity and fitness. Front Cell Infect Microbiol 2023; 13:1130749. [PMID: 36968111 PMCID: PMC10034770 DOI: 10.3389/fcimb.2023.1130749] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 02/13/2023] [Indexed: 03/11/2023] Open
Abstract
IntroductionFlaviviruses like dengue virus (DENV) and Zika virus (ZIKV) are mosquito-borne viruses that cause febrile, hemorrhagic, and neurological diseases in humans, resulting in 400 million infections annually. Due to their co-circulation in many parts of the world, flaviviruses must replicate in the presence of pre-existing adaptive immune responses targeted at serologically closely related pathogens, which can provide protection or enhance disease. However, the impact of pre-existing cross-reactive immunity as a driver of flavivirus evolution, and subsequently the implications on the emergence of immune escape variants, is poorly understood. Therefore, we investigated how replication in the presence of convalescent dengue serum drives ZIKV evolution.MethodsWe used an in vitro directed evolution system, passaging ZIKV in the presence of serum from humans previously infected with DENV (anti-DENV) or serum from DENV-naïve patients (control serum). Following five passages in the presence of serum, we performed next-generation sequencing to identify mutations that arose during passaging. We studied two non-synonymous mutations found in the anti-DENV passaged population (E-V355I and NS1-T139A) by generating individual ZIKV mutants and assessing fitness in mammalian cells and live mosquitoes, as well as their sensitivity to antibody neutralization.Results and discussionBoth viruses had increased fitness in Vero cells with and without the addition of anti-DENV serum and in human lung epithelial and monocyte cells. In Aedes aegypti mosquitoes—using blood meals with and without anti-DENV serum—the mutant viruses had significantly reduced fitness compared to wild-type ZIKV. These results align with the trade-off hypothesis of constrained mosquito-borne virus evolution. Notably, only the NS1-T139A mutation escaped neutralization, while E-V335I demonstrated enhanced neutralization sensitivity to neutralization by anti-DENV serum, indicating that neutralization escape is not necessary for viruses passaged under cross-reactive immune pressures. Future studies are needed to assess cross-reactive immune selection in humans and relevant animal models or with different flaviviruses.
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Affiliation(s)
- Jeffrey M. Marano
- Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Roanoke, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States
| | - James Weger-Lucarelli
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States
- *Correspondence: James Weger-Lucarelli,
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Munasinghe E, Athapaththu M, Abeyewickreme W. Immuno-dominant dengue NS1 peptides as antigens for production of monoclonal antibodies. Front Mol Biosci 2022; 9:935456. [PMID: 36339720 PMCID: PMC9635855 DOI: 10.3389/fmolb.2022.935456] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 10/04/2022] [Indexed: 08/23/2023] Open
Abstract
Synthetic peptides have recently become common as antigens for antibody production. Peptides are short chains of amino acids that can be used to elicit an immune response. The immunogenicity of the peptide antigens varies depending on the length, charge, solubility, and amino acids contained in the peptide sequence. Dengue NS1 protein is an important target antigen in the early detection of dengue infection. In this study, peptides corresponding to a highly conserved region from the dengue NS1 region were designed and synthesized. Balb/C mice were immunized against each peptide and spleen cells extracted from the immunized mice were fused with NS0 murine myeloma cells. Hybridoma clones obtained from the fusions were tested against peptides using ELISA. Out of 1,830 growing clones, 28 clones produced antibodies reacting with dengue NS1 peptides. A purified monoclonal antibody reacting with all four peptides was tested for reactivity with dengue NS1 native protein using dengue-confirmed serum and urine samples. The monoclonal antibody shows significant reactivity with both serum and urine. The findings of the current research can be used to detect dengue infection using urine, which ultimately results in the prevention of dengue epidemics through painless diagnosis, following treatment, and patient management to safeguard human and economic wellness.
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Affiliation(s)
| | | | - Wimaladharma Abeyewickreme
- Department of Para Clinical Sciences, Faculty of Medicine, General Sir John Kotelawala Defence University, Ratmalana, Sri Lanka
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8
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Flavivirus NS1 Triggers Tissue-Specific Disassembly of Intercellular Junctions Leading to Barrier Dysfunction and Vascular Leak in a GSK-3β-Dependent Manner. Pathogens 2022; 11:pathogens11060615. [PMID: 35745469 PMCID: PMC9228372 DOI: 10.3390/pathogens11060615] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/13/2022] [Accepted: 05/19/2022] [Indexed: 02/05/2023] Open
Abstract
The flavivirus nonstructural protein 1 (NS1) is secreted from infected cells and contributes to endothelial barrier dysfunction and vascular leak in a tissue-dependent manner. This phenomenon occurs in part via disruption of the endothelial glycocalyx layer (EGL) lining the endothelium. Additionally, we and others have shown that soluble DENV NS1 induces disassembly of intercellular junctions (IJCs), a group of cellular proteins critical for maintaining endothelial homeostasis and regulating vascular permeability; however, the specific mechanisms by which NS1 mediates IJC disruption remain unclear. Here, we investigated the relative contribution of five flavivirus NS1 proteins, from dengue (DENV), Zika (ZIKV), West Nile (WNV), Japanese encephalitis (JEV), and yellow fever (YFV) viruses, to the expression and localization of the intercellular junction proteins β-catenin and VE-cadherin in endothelial cells from human umbilical vein and brain tissues. We found that flavivirus NS1 induced the mislocalization of β-catenin and VE-cadherin in a tissue-dependent manner, reflecting flavivirus disease tropism. Mechanistically, we observed that NS1 treatment of cells triggered internalization of VE-cadherin, likely via clathrin-mediated endocytosis, and phosphorylation of β-catenin, part of a canonical IJC remodeling pathway during breakdown of endothelial barriers that activates glycogen synthase kinase-3β (GSK-3β). Supporting this model, we found that a chemical inhibitor of GSK-3β reduced both NS1-induced permeability of human umbilical vein and brain microvascular endothelial cell monolayers in vitro and vascular leakage in a mouse dorsal intradermal model. These findings provide insight into the molecular mechanisms regulating NS1-mediated endothelial dysfunction and identify GSK-3β as a potential therapeutic target for treatment of vascular leakage during severe dengue disease.
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Shoushtari M, Mafakher L, Rahmati S, Salehi-Vaziri M, Arashkia A, Roohvand F, Teimoori-Toolabi L, Azadmanesh K. Designing vaccine candidates against dengue virus by in silico studies on structural and nonstructural domains. Mol Cell Probes 2022; 63:101818. [DOI: 10.1016/j.mcp.2022.101818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/06/2022] [Accepted: 04/18/2022] [Indexed: 11/16/2022]
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Abstract
The dengue virus NS1 is a multifunctional protein that forms part of replication complexes. NS1 is also secreted, as a hexamer, to the extracellular milieu. Circulating NS1 has been associated with dengue pathogenesis by several mechanisms. Cell binding and internalization of soluble NS1 result in endothelial hyperpermeability and in the downregulation of the innate immune response. In this work, we report that the HDL scavenger receptor B1 (SRB1) in human hepatic cells and a scavenger receptor B1-like in mosquito C6/36 cells act as cell surface binding receptors for dengue virus NS1. The presence of the SRB1 on the plasma membrane of C6/36 cells, as well as in Huh7 cells, was demonstrated by confocal microscopy. The internalization of NS1 can be efficiently blocked by anti-SRB1 antibodies, and previous incubation of the cells with HDL significantly reduces NS1 internalization. Significant reduction in NS1 internalization was observed in C6/36 cells transfected with siRNAs specific for SRB1. In addition, the transient expression of SRB1 in Vero cells, which lacks the receptor, allows NS1 internalization in these cells. Direct interaction between soluble NS1 and the SRB1 in Huh7 and C6/36 cells was demonstrated in situ by proximity ligation assays and in vitro by surface plasmon resonance. Finally, results are presented indicating that the SRB1 also acts as a cell receptor for Zika virus NS1. These results demonstrate that dengue virus NS1, a bona fide lipoprotein, usurps the HDL receptor for cell entry and offers explanations for the altered serum lipoprotein homeostasis observed in dengue patients. IMPORTANCE Dengue is the most common viral disease transmitted to humans by mosquitoes. The dengue virus NS1 is a multifunctional glycoprotein necessary for viral replication. NS1 is also secreted as a hexameric lipoprotein and circulates in high concentrations in the sera of patients. Circulating NS1 has been associated with dengue pathogenesis by several mechanisms, including favoring of virus replication in hepatocytes and dendritic cells and disruption of the endothelial glycocalyx leading to hyperpermeability. Those last actions require NS1 internalization. Here, we identify the scavenger cell receptor B1, as the cell-binding receptor for dengue and Zika virus NS1, in cultured liver and in mosquito cells. The results indicate that flavivirus NS1, a bona fide lipoprotein, usurps the human HDL receptor and may offer explanations for the alterations in serum lipoprotein homeostasis observed in dengue patients.
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Wang WH, Urbina AN, Lin CY, Yang ZS, Assavalapsakul W, Thitithanyanont A, Lu PL, Chen YH, Wang SF. Targets and strategies for vaccine development against dengue viruses. Biomed Pharmacother 2021; 144:112304. [PMID: 34634560 DOI: 10.1016/j.biopha.2021.112304] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 10/04/2021] [Accepted: 10/05/2021] [Indexed: 10/20/2022] Open
Abstract
Dengue virus (DENV) is a global health threat causing about half of the worldwide population to be at risk of infection, especially the people living in tropical and subtropical area. Although the dengue disease caused by dengue virus (DENV) is asymptomatic and self-limiting in most people with first infection, increased severe dengue symptoms may be observed in people with heterotypic secondary DENV infection. Since there is a lack of specific antiviral medication, the development of dengue vaccines is critical in the prevention and control this disease. Several targets and strategies in the development of dengue vaccine have been demonstrated. Currently, Dengvaxia, a live-attenuated chimeric yellow-fever/tetravalent dengue vaccine (CYD-TDV) developed by Sanofi Pasteur, has been licensed and approved for clinical use in some countries. However, this vaccine has demonstrated low efficacy in children and dengue-naïve individuals and also increases the risk of severe dengue in young vaccinated recipients. Accordingly, many novel strategies for the dengue vaccine are under investigation and development. Here, we conducted a systemic literature review according to PRISMA guidelines to give a concise overview of various aspects of the vaccine development process against DENVs, mainly targeting five potential strategies including live attenuated vaccine, inactivated virus vaccine, recombinant subunit vaccine, viral-vector vaccine, and DNA vaccine. This study offers the comprehensive view of updated information and current progression of immunogen selection as well as strategies of vaccine development against DENVs.
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Affiliation(s)
- Wen-Hung Wang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical, University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Aspiro Nayim Urbina
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Chih-Yen Lin
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Zih-Syuan Yang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wanchai Assavalapsakul
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Arunee Thitithanyanont
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Po-Liang Lu
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical, University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yen-Hsu Chen
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical, University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Sheng-Fan Wang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
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Wessel AW, Dowd KA, Biering SB, Zhang P, Edeling MA, Nelson CA, Funk KE, DeMaso CR, Klein RS, Smith JL, Cao TM, Kuhn RJ, Fremont DH, Harris E, Pierson TC, Diamond MS. Levels of Circulating NS1 Impact West Nile Virus Spread to the Brain. J Virol 2021; 95:e0084421. [PMID: 34346770 PMCID: PMC8475509 DOI: 10.1128/jvi.00844-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 07/28/2021] [Indexed: 12/15/2022] Open
Abstract
Dengue virus (DENV) and West Nile virus (WNV) are arthropod-transmitted flaviviruses that cause systemic vascular leakage and encephalitis syndromes, respectively, in humans. However, the viral factors contributing to these specific clinical disorders are not completely understood. Flavivirus nonstructural protein 1 (NS1) is required for replication, expressed on the cell surface, and secreted as a soluble glycoprotein, reaching high levels in the blood of infected individuals. Extracellular DENV NS1 and WNV NS1 interact with host proteins and cells, have immune evasion functions, and promote endothelial dysfunction in a tissue-specific manner. To characterize how differences in DENV NS1 and WNV NS1 might function in pathogenesis, we generated WNV NS1 variants with substitutions corresponding to residues found in DENV NS1. We discovered that the substitution NS1-P101K led to reduced WNV infectivity in the brain and attenuated lethality in infected mice, although the virus replicated efficiently in cell culture and peripheral organs and bound at wild-type levels to brain endothelial cells and complement components. The P101K substitution resulted in reduced NS1 antigenemia in mice, and this was associated with reduced WNV spread to the brain. Because exogenous administration of NS1 protein rescued WNV brain infectivity in mice, we conclude that circulating WNV NS1 facilitates viral dissemination into the central nervous system and impacts disease outcomes. IMPORTANCE Flavivirus NS1 serves as an essential scaffolding molecule during virus replication but also is expressed on the cell surface and is secreted as a soluble glycoprotein that circulates in the blood of infected individuals. Although extracellular forms of NS1 are implicated in immune modulation and in promoting endothelial dysfunction at blood-tissue barriers, it has been challenging to study specific effects of NS1 on pathogenesis without disrupting its key role in virus replication. Here, we assessed WNV NS1 variants that do not affect virus replication and evaluated their effects on pathogenesis in mice. Our characterization of WNV NS1-P101K suggests that the levels of NS1 in the circulation facilitate WNV dissemination to the brain and affect disease outcomes. Our findings facilitate understanding of the role of NS1 during flavivirus infection and support antiviral strategies for targeting circulating forms of NS1.
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Affiliation(s)
- Alex W. Wessel
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kimberly A. Dowd
- Viral Pathogenesis Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Scott B. Biering
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Ping Zhang
- Department of Immunology, Key Laboratory of Tropical Diseases Control, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Melissa A. Edeling
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Christopher A. Nelson
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kristen E. Funk
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Christina R. DeMaso
- Viral Pathogenesis Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Robyn S. Klein
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, USA
- Center for Neuroimmunology and Neuroinfectious Diseases, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Janet L. Smith
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Thu Minh Cao
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA
| | - Richard J. Kuhn
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA
| | - Daved H. Fremont
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Theodore C. Pierson
- Viral Pathogenesis Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Michael S. Diamond
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
- The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St. Louis, Missouri, USA
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13
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Chen Z, He S, Xu R, Han Q, Xia X, Song Y, Zhang J. Nanobead-Based Screening Method for Antibody Pairing of Dengue Virus Nonstructural Protein-1. J Biomed Nanotechnol 2021; 17:1788-1797. [PMID: 34688323 DOI: 10.1166/jbn.2021.3148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Dengue fever is a classic mosquito viral disease. Dengue virus non-structural protein-1 as a membrane-associated homologous dimer anchored to the surface of infected cells and also secreted into the blood. The nonstructural protein-1 levels are related to disease severity, and the presence of nonstructural protein-1 secreted from cells to the serum of people infected with the dengue virus is an early marker of infection. Paired antibodies are key in the establishment of rapid detection technology. In this study, the prepared recombinant nonstructural protein-1 protein of dengue virus serotype 3 was purified by the prokaryotic expression, and prepared monoclonal antibodies by cell fusion. A method for paired antibody screening was established based on the N-hydroxy succinimide-nanobeads and the prepared monoclonal antibodies. A simple and rapid point-of-care system integrating the paired antibodies and lateral flow assay was established to verify the screened antibody pairs. The results confirmed that the antibody pair screening method based on N-hydroxy succinimide-nanobeads is feasible.
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Affiliation(s)
- Zhixin Chen
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Shuzhen He
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Ruixian Xu
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Qinqin Han
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Xueshan Xia
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Yuzhu Song
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jinyang Zhang
- Research Center of Molecular Medicine of Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
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14
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Dechtawewat T, Roytrakul S, Yingchutrakul Y, Charoenlappanit S, Siridechadilok B, Limjindaporn T, Mangkang A, Prommool T, Puttikhunt C, Songprakhon P, Kongmanas K, Kaewjew N, Avirutnan P, Yenchitsomanus PT, Malasit P, Noisakran S. Potential Phosphorylation of Viral Nonstructural Protein 1 in Dengue Virus Infection. Viruses 2021; 13:v13071393. [PMID: 34372598 PMCID: PMC8310366 DOI: 10.3390/v13071393] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/12/2021] [Accepted: 07/14/2021] [Indexed: 12/27/2022] Open
Abstract
Dengue virus (DENV) infection causes a spectrum of dengue diseases that have unclear underlying mechanisms. Nonstructural protein 1 (NS1) is a multifunctional protein of DENV that is involved in DENV infection and dengue pathogenesis. This study investigated the potential post-translational modification of DENV NS1 by phosphorylation following DENV infection. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), 24 potential phosphorylation sites were identified in both cell-associated and extracellular NS1 proteins from three different cell lines infected with DENV. Cell-free kinase assays also demonstrated kinase activity in purified preparations of DENV NS1 proteins. Further studies were conducted to determine the roles of specific phosphorylation sites on NS1 proteins by site-directed mutagenesis with alanine substitution. The T27A and Y32A mutations had a deleterious effect on DENV infectivity. The T29A, T230A, and S233A mutations significantly decreased the production of infectious DENV but did not affect relative levels of intracellular DENV NS1 expression or NS1 secretion. Only the T230A mutation led to a significant reduction of detectable DENV NS1 dimers in virus-infected cells; however, none of the mutations interfered with DENV NS1 oligomeric formation. These findings highlight the importance of DENV NS1 phosphorylation that may pave the way for future target-specific antiviral drug design.
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Affiliation(s)
- Thanyaporn Dechtawewat
- Division of Molecular Medicine, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (T.D.); (P.S.); (P.-t.Y.)
| | - Sittiruk Roytrakul
- Functional Proteomics Technology Laboratory, Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand; (S.R.); (Y.Y.); (S.C.)
| | - Yodying Yingchutrakul
- Functional Proteomics Technology Laboratory, Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand; (S.R.); (Y.Y.); (S.C.)
| | - Sawanya Charoenlappanit
- Functional Proteomics Technology Laboratory, Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand; (S.R.); (Y.Y.); (S.C.)
| | - Bunpote Siridechadilok
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
| | - Thawornchai Limjindaporn
- Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand;
| | - Arunothai Mangkang
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
| | - Tanapan Prommool
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Chunya Puttikhunt
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Pucharee Songprakhon
- Division of Molecular Medicine, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (T.D.); (P.S.); (P.-t.Y.)
| | - Kessiri Kongmanas
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Nuttapong Kaewjew
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Panisadee Avirutnan
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Pa-thai Yenchitsomanus
- Division of Molecular Medicine, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (T.D.); (P.S.); (P.-t.Y.)
| | - Prida Malasit
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Sansanee Noisakran
- Molecular Biology of Dengue and Flaviviruses Research Team, Medical Molecular Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand; (B.S.); (A.M.); (T.P.); (C.P.); (P.M.)
- Division of Dengue Hemorrhagic Fever Research, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (K.K.); (N.K.); (P.A.)
- Siriraj Center of Research Excellence in Dengue and Emerging Pathogens, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Correspondence: or ; Tel.: +66-2-419-6666
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15
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Dengue and the Lectin Pathway of the Complement System. Viruses 2021; 13:v13071219. [PMID: 34202570 PMCID: PMC8310334 DOI: 10.3390/v13071219] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/17/2021] [Accepted: 06/19/2021] [Indexed: 12/15/2022] Open
Abstract
Dengue is a mosquito-borne viral disease causing significant health and economic burdens globally. The dengue virus (DENV) comprises four serotypes (DENV1-4). Usually, the primary infection is asymptomatic or causes mild dengue fever (DF), while secondary infections with a different serotype increase the risk of severe dengue disease (dengue hemorrhagic fever, DHF). Complement system activation induces inflammation and tissue injury, contributing to disease pathogenesis. However, in asymptomatic or primary infections, protective immunity largely results from the complement system’s lectin pathway (LP), which is activated through foreign glycan recognition. Differences in N-glycans displayed on the DENV envelope membrane influence the lectin pattern recognition receptor (PRR) binding efficiency. The important PRR, mannan binding lectin (MBL), mediates DENV neutralization through (1) a complement activation-independent mechanism via direct MBL glycan recognition, thereby inhibiting DENV attachment to host target cells, or (2) a complement activation-dependent mechanism following the attachment of complement opsonins C3b and C4b to virion surfaces. The serum concentrations of lectin PRRs and their polymorphisms influence these LP activities. Conversely, to escape the LP attack and enhance the infectivity, DENV utilizes the secreted form of nonstructural protein 1 (sNS1) to counteract the MBL effects, thereby increasing viral survival and dissemination.
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16
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Moradi F, Lotfi K, Armin M, Clark CCT, Askari G, Rouhani MH. The association between serum homocysteine and depression: A systematic review and meta-analysis of observational studies. Eur J Clin Invest 2021; 51:e13486. [PMID: 33423269 DOI: 10.1111/eci.13486] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Hyperhomocysteinaemia is known to interfere with neurological functions; however, there is a controversy regarding the relationship between homocysteine and depression. MATERIALS AND METHODS Science Direct, MEDLINE and ISI Web of Science were searched to find relevant articles, published up to August 2020. Studies were included if they compared homocysteine levels in healthy subjects with subjects with depression. Also, articles that reported the association between hyperhomocysteinaemia and risk of depression were included. Odds ratios of depression and means of homocysteine were used to ascertain the overall effect size. RESULTS Homocysteine level was higher in subjects with depression in comparison with healthy controls (weight mean difference = 2.53 µmol/L, 95% confidence interval: 1.77, 3.30), and the depression diagnostic tool was a source of heterogeneity. Homocysteine level was significantly higher in subjects with depression in studies that used Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV), Geriatric Depression Scale (GDS), Zung Self-Rating Depression Scale (ZDRS) and Beck Depression Index II (BDI-II) as depression diagnostic tools. Also, participants with hyperhomocysteinaemia had a higher chance of depression (Pooled risk = 1.34, 95% confidence interval: 1.19, 1.52), where the depression diagnostic tool was a source of heterogeneity. In contrast to ZDRS and Patient Health Questionnaire (PHQ) subgroups, hyperhomocysteinaemia yielded a significantly higher risk of depression in DSM-IV, GDS and 'other' subgroups. CONCLUSION Homocysteinemia level is higher in individuals with depression. However, the depression diagnostic tool used is instrumental in influencing their association, and thus, future studies should focus on the tools for depression assessment.
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Affiliation(s)
- Fatemeh Moradi
- Student Research Committee, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Keyhan Lotfi
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Armin
- Food Security Research Center, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Cain C T Clark
- Centre for Intelligent Healthcare, Coventry University, Coventry, UK
| | - Gholamreza Askari
- Food Security Research Center, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Hossein Rouhani
- Food Security Research Center, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
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17
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Iani FCDM, Caetano ACB, Cocovich JCW, Amâncio FF, Pereira MA, Adelino TÉR, Caldas S, Silva MVF, Pereira GDC, Duarte MM. Dengue diagnostics: serious inaccuracies are likely to occur if pre-analytical conditions are not strictly followed. Mem Inst Oswaldo Cruz 2021; 115:e200287. [PMID: 33533869 PMCID: PMC7849175 DOI: 10.1590/0074-02760200287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 11/30/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND The heat-labile nature of Dengue virus (DENV) in serum samples must be considered when applying routine diagnostic tests to avoid issues that could impact the accuracy of test results with direct implications for case management and disease reporting. OBJECTIVES To check if pre-analytical variables, such as storage time and temperature, have an impact on the accuracy of the main routine diagnostic tests for dengue. METHODS Virus isolation, reverse transcription real-time polymerase chain reaction (RT-PCR) and NS1 enzyme-linked immunosorbent assay (ELISA) were evaluated using 84 samples submitted to different pre-analytical conditions. FINDINGS Sensitivity and negative predictive value were directly affected by sample storage conditions. RT-PCR and virus isolation showed greater dependence on well-conserved samples for an accurate diagnosis. Interestingly, even storage at -30ºC for a relatively short time (15 days) was not adequate for accurate results using virus isolation and RT-PCR tests. On the other hand, NS1 ELISA showed no significant reduction in positivity for aliquots tested under the same conditions as in the previous tests. MAIN CONCLUSIONS Our results support the stability of the NS1 marker in ELISA diagnosis and indicate that the accuracy of routine tests such as virus isolation and RT-PCR is significantly affected by inadequate transport and storage conditions of serum samples.
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Affiliation(s)
- Felipe Campos de Melo Iani
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
| | | | | | - Frederico Figueiredo Amâncio
- Universidade Federal de Minas Gerais, Faculdade de Medicina, Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Belo Horizonte, MG, Brasil
| | - Maira Alves Pereira
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
| | - Talita Émile Ribeiro Adelino
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
| | - Sérgio Caldas
- Fundação Ezequiel Dias, Diretoria de Pesquisa e Desenvolvimento, Serviço de Biotecnologia e Saúde, Belo Horizonte, MG, Brasil
| | - Marcos Vinícius Ferreira Silva
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
| | - Glauco de Carvalho Pereira
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
| | - Myrian Morato Duarte
- Fundação Ezequiel Dias, Diretoria do Instituto Octávio Magalhães, Serviço de Virologia e Riquetsioses, Belo Horizonte, MG, Brasil
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18
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del Valle-Mendoza J, Aguilar-Luis M, Carrillo-Ng H, Kym S, Silva-Caso W, Verne E, del Valle L, Bazán-Mayra J, Zavaleta-Gavidia V, Cornejo-Pacherres D, Tarazona-Castro Y, Aquino-Ortega R, Cornejo-Tapia A. Detection of dengue virus serotype 3 in Cajamarca, Peru: Molecular diagnosis and clinical characteristics. ASIAN PAC J TROP MED 2021. [DOI: 10.4103/1995-7645.326257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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19
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Peptides targeting dengue viral nonstructural protein 1 inhibit dengue virus production. Sci Rep 2020; 10:12933. [PMID: 32737386 PMCID: PMC7395749 DOI: 10.1038/s41598-020-69515-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022] Open
Abstract
Viruses manipulate the life cycle in host cells via the use of viral properties and host machineries. Development of antiviral peptides against dengue virus (DENV) infection has previously been concentrated on blocking the actions of viral structural proteins and enzymes in virus entry and viral RNA processing in host cells. In this study, we proposed DENV NS1, which is a multifunctional non-structural protein indispensable for virus production, as a new target for inhibition of DENV infection by specific peptides. We performed biopanning assays using a phage-displayed peptide library and identified 11 different sequences of 12-mer peptides binding to DENV NS1. In silico analyses of peptide-protein interactions revealed 4 peptides most likely to bind to DENV NS1 at specific positions and their association was analysed by surface plasmon resonance. Treatment of Huh7 cells with these 4 peptides conjugated with N-terminal fluorescent tag and C-terminal cell penetrating tag at varying time-of-addition post-DENV infection could inhibit the production of DENV-2 in a time- and dose-dependent manner. The inhibitory effects of the peptides were also observed in other virus serotypes (DENV-1 and DENV-4), but not in DENV-3. These findings indicate the potential application of peptides targeting DENV NS1 as antiviral agents against DENV infection.
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20
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Puerta-Guardo H, Glasner DR, Espinosa DA, Biering SB, Patana M, Ratnasiri K, Wang C, Beatty PR, Harris E. Flavivirus NS1 Triggers Tissue-Specific Vascular Endothelial Dysfunction Reflecting Disease Tropism. Cell Rep 2020; 26:1598-1613.e8. [PMID: 30726741 PMCID: PMC6934102 DOI: 10.1016/j.celrep.2019.01.036] [Citation(s) in RCA: 170] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/27/2018] [Accepted: 01/09/2019] [Indexed: 01/22/2023] Open
Abstract
Flaviviruses cause systemic or neurotropic-encephalitic pathology in humans. The flavivirus nonstructural protein 1 (NS1) is a secreted glycoprotein involved in viral replication, immune evasion, and vascular leakage during dengue virus infection. However, the contribution of secreted NS1 from related flaviviruses to viral pathogenesis remains unknown. Here, we demonstrate that NS1 from dengue, Zika, West Nile, Japanese encephalitis, and yellow fever viruses selectively binds to and alters permeability of human endothelial cells from lung, dermis, umbilical vein, brain, and liver in vitro and causes tissue-specific vascular leakage in mice, reflecting the pathophysiology of each flavivirus. Mechanistically, each flavivirus NS1 leads to differential disruption of endothelial glycocalyx components, resulting in endothelial hyperpermeability. Our findings reveal the capacity of a secreted viral protein to modulate endothelial barrier function in a tissue-specific manner both in vitro and in vivo, potentially influencing virus dissemination and pathogenesis and providing targets for antiviral therapies and vaccine development. Puerta-Guardo et al. discover that five flavivirus NS1 proteins trigger hyperpermeability and vascular dysfunction in human endothelial cells and mice in a manner reflecting disease tropism. This tissue-specific tropism is partially determined by the capacity of NS1 to bind endothelial cells and is characterized by disruption of endothelial glycocalyx components.
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Affiliation(s)
- Henry Puerta-Guardo
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Dustin R Glasner
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Diego A Espinosa
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Scott B Biering
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Mark Patana
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Kalani Ratnasiri
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Chunling Wang
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - P Robert Beatty
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA.
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21
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Barbachano-Guerrero A, Endy TP, King CA. Dengue virus non-structural protein 1 activates the p38 MAPK pathway to decrease barrier integrity in primary human endothelial cells. J Gen Virol 2020; 101:484-496. [PMID: 32141809 DOI: 10.1099/jgv.0.001401] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Dengue virus (DENV) causes an estimated 390 million infections worldwide annually, with severe forms of disease marked by vascular leakage. Endothelial cells (EC) are directly responsible for vascular homeostasis and are highly responsive to circulating mediators but are not commonly infected. DENV encodes seven non-structural (NS) proteins; with only one of those, NS1, secreted from infected cells and accumulating in the blood of patients. NS1 has been implicated in the pathogenesis of vascular permeability, but the mechanism is not completely understood. Here we used primary endothelial cells and an array of in vitro approaches to study the effect of NS1 in disease-relevant human ECs. Confocal microscopy demonstrated rapid NS1 internalization by ECs into endosomes with accumulation over time. Transcriptomic and pathway analysis showed significant changes in functions associated with EC homeostasis and vascular permeability. Functional significance of this activation was assessed by trans-endothelial electrical resistance and showed that NS1 induced rapid and transient loss in EC barrier function within 3 h post-treatment. To understand the molecular mechanism by which NS1 induced EC activation, we evaluated the stress-sensing p38 MAPK pathway known to be directly involved in EC permeability and inflammation. WB analysis of NS1-stimulated ECs showed clear activation of p38 MAPK and downstream effectors MAPKAPK-2 and HSP27 with chemical inhibition of the p38 MAP kinase pathway restoring barrier function. Our results suggest that DENV NS1 may be involved in the pathogenesis of severe dengue by activating the p38 MAPK in ECs, promoting increased permeability that characterizes severe disease.
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Affiliation(s)
| | - Timothy P Endy
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse NY, USA
| | - Christine A King
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse NY, USA
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22
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Furnon W, Fender P, Confort MP, Desloire S, Nangola S, Kitidee K, Leroux C, Ratinier M, Arnaud F, Lecollinet S, Boulanger P, Hong SS. Remodeling of the Actin Network Associated with the Non-Structural Protein 1 (NS1) of West Nile Virus and Formation of NS1-Containing Tunneling Nanotubes. Viruses 2019; 11:v11100901. [PMID: 31569658 PMCID: PMC6832617 DOI: 10.3390/v11100901] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/24/2019] [Accepted: 09/24/2019] [Indexed: 12/14/2022] Open
Abstract
The cellular response to the recombinant NS1 protein of West Nile virus (NS1WNV) was studied using three different cell types: Vero E6 simian epithelial cells, SH-SY5Y human neuroblastoma cells, and U-87MG human astrocytoma cells. Cells were exposed to two different forms of NS1WNV: (i) the exogenous secreted form, sNS1WNV, added to the extracellular milieu; and (ii) the endogenous NS1WNV, the intracellular form expressed in plasmid-transfected cells. The cell attachment and uptake of sNS1WNV varied with the cell type and were only detectable in Vero E6 and SH-SY5Y cells. Addition of sNS1WNV to the cell culture medium resulted in significant remodeling of the actin filament network in Vero E6 cells. This effect was not observed in SH-SY5Y and U-87MG cells, implying that the cellular uptake of sNS1WNV and actin network remodeling were dependent on cell type. In the three cell types, NS1WNV-expressing cells formed filamentous projections reminiscent of tunneling nanotubes (TNTs). These TNT-like projections were found to contain actin and NS1WNV proteins. Interestingly, similar actin-rich, TNT-like filaments containing NS1WNV and the viral envelope glycoprotein EWNV were also observed in WNV-infected Vero E6 cells.
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Affiliation(s)
- Wilhelm Furnon
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
| | - Pascal Fender
- Institut de Biologie Structurale, CNRS UMR 5075, 38042 Grenoble, France.
| | - Marie-Pierre Confort
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
| | - Sophie Desloire
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
| | - Sawitree Nangola
- Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao 56000, Thailand.
| | - Kuntida Kitidee
- Center for Research & Innovation, Faculty of Medical Technology, Mahidol University, Nakhon Pathom 73170, Thailand.
| | - Caroline Leroux
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
| | - Maxime Ratinier
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
- EPHE, PSL Research University, INRA, Université de Lyon, University Claude Bernard Lyon 1, UMR754, IVPC, Cedex 07, 69366 Lyon, France.
| | - Frédérick Arnaud
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
- EPHE, PSL Research University, INRA, Université de Lyon, University Claude Bernard Lyon 1, UMR754, IVPC, Cedex 07, 69366 Lyon, France.
| | - Sylvie Lecollinet
- UMR-1161 Virology, ANSES, INRA, Ecole Nationale Vétérinaire d'Alfort, ANSES Animal Health Laboratory, EURL on Equine Diseases, 94704 Maisons-Alfort, France.
| | - Pierre Boulanger
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
| | - Saw-See Hong
- Université de Lyon, University Claude Bernard Lyon 1, INRA, EPHE, IVPC, UMR754, Viral Infections & Comparative Pathology, Cedex 07, 69366 Lyon, France.
- Institut National de la Santé et de la Recherche Médicale, 101, rue de Tolbiac, Cedex 13, 75654 Paris, France.
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Hijacking the Host Immune Cells by Dengue Virus: Molecular Interplay of Receptors and Dengue Virus Envelope. Microorganisms 2019; 7:microorganisms7090323. [PMID: 31489877 PMCID: PMC6780243 DOI: 10.3390/microorganisms7090323] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 02/06/2023] Open
Abstract
Dengue virus (DENV) is one of the lethal pathogens in the hot climatic regions of the world and has been extensively studied to decipher its mechanism of pathogenesis and the missing links of its life cycle. With respect to the entry of DENV, multiple receptors have been recognized in different cells of the human body. However, scientists still argue whether these identified receptors are the exclusive entry mediators for the virus. Adding to the complexity, DENV has been reported to be infecting multiple organ types in its human host. Also, more than one receptor in a particular cell has been discerned to take part in mediating the ingress of DENV. In this review, we aim to discuss the different cells of the human immune system that support DENV infection and their corresponding receptors that DENV deploy to gain access to the cells.
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Abstract
This is a selective review of recent publications on dengue clinical features, epidemiology, pathogenesis, and vaccine development placed in a context of observations made over the past half century. Four dengue viruses (DENVs) are transmitted by urban cycle mosquitoes causing diseases whose nature and severity are influenced by interacting factors such as virus, age, immune status of the host, and human genetic variability. A phenomenon that controls the kinetics of DENV infection, antibody-dependent enhancement, best explains the correlation of the vascular permeability syndrome with second heterotypic DENV infections and infection in the presence of passively acquired antibodies. Based on growing evidence in vivo and in vitro, the tissue-damaging DENV non-structural protein 1 (NS1) is responsible for most of the pathophysiological features of severe dengue. This review considers the contribution of hemophagocytic histiocytosis syndrome to cases of severe dengue, the role of movement of humans in dengue epidemiology, and modeling and planning control programs and describes a country-wide survey for dengue infections in Bangladesh and efforts to learn what controls the clinical outcome of dengue infections. Progress and problems with three tetravalent live-attenuated vaccines are reviewed. Several research mysteries remain: why is the risk of severe disease during second heterotypic DENV infection so low, why is the onset of vascular permeability correlated with defervescence, and what are the crucial components of protective immunity?
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Affiliation(s)
- Scott Halstead
- Emeritus Professor, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
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25
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Wang C, Puerta-Guardo H, Biering SB, Glasner DR, Tran EB, Patana M, Gomberg TA, Malvar C, Lo NTN, Espinosa DA, Harris E. Endocytosis of flavivirus NS1 is required for NS1-mediated endothelial hyperpermeability and is abolished by a single N-glycosylation site mutation. PLoS Pathog 2019; 15:e1007938. [PMID: 31356638 PMCID: PMC6687192 DOI: 10.1371/journal.ppat.1007938] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 08/08/2019] [Accepted: 06/22/2019] [Indexed: 12/22/2022] Open
Abstract
Arthropod-borne flaviviruses cause life-threatening diseases associated with endothelial hyperpermeability and vascular leak. We recently found that vascular leak can be triggered by dengue virus (DENV) non-structural protein 1 (NS1) via the disruption of the endothelial glycocalyx-like layer (EGL). However, the molecular determinants of NS1 required to trigger EGL disruption and the cellular pathway(s) involved remain unknown. Here we report that mutation of a single glycosylated residue of NS1 (N207Q) abolishes the ability of NS1 to trigger EGL disruption and induce endothelial hyperpermeability. Intriguingly, while this mutant bound to the surface of endothelial cells comparably to wild-type NS1, it was no longer internalized, suggesting that NS1 binding and internalization are distinct steps. Using endocytic pathway inhibitors and gene-specific siRNAs, we determined that NS1 was endocytosed into endothelial cells in a dynamin- and clathrin-dependent manner, which was required to trigger endothelial dysfunction in vitro and vascular leak in vivo. Finally, we found that the N207 glycosylation site is highly conserved among flaviviruses and is also essential for West Nile and Zika virus NS1 to trigger endothelial hyperpermeability via clathrin-mediated endocytosis. These data provide critical mechanistic insight into flavivirus NS1-induced pathogenesis, presenting novel therapeutic and vaccine targets for flaviviral diseases. Vascular leak is a hallmark of severe dengue disease. Recently, our group revealed a critical role for NS1 in induction of endothelial hyperpermeability and vascular leakage in an endothelial cell-intrinsic manner. However, the upstream pathway triggered by NS1, as well as the molecular determinants of NS1 required for this phenomenon, remain obscure. Gaining insight into this endothelial cell-intrinsic pathway is critical for understanding dengue pathogenesis, developing novel antiviral therapies, and developing NS1-based vaccine approaches that pose a minimal risk of antibody-dependent enhancement. Our current study expands our knowledge of this novel pathway not only by identifying the requirement of internalization of secreted NS1 via clathrin-mediated endocytosis, but also by pinpointing the NS1 molecular determinant (N207) required to trigger vascular leak. Further, our work identifies N207 as a residue conserved among multiple flaviviruses (Zika virus and West Nile virus, in addition to DENV), which is critical for NS1-mediated vascular leak in biologically relevant human endothelial cells modeling interstitial compartments in the lung or the blood-brain barrier. Thus, our study identifies endocytosis and a single amino acid (N207) of the NS1 viral toxin as critical for pan-flavivirus pathogenesis, representing a novel target for anti-flaviviral therapy and vaccine development.
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Affiliation(s)
- Chunling Wang
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Henry Puerta-Guardo
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Scott B. Biering
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Dustin R. Glasner
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Edwina B. Tran
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Mark Patana
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Trent A. Gomberg
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Carmel Malvar
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Nicholas T. N. Lo
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Diego A. Espinosa
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
- * E-mail:
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26
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Sharma N, Mishra KP, Chanda S, Bhardwaj V, Tanwar H, Ganju L, Kumar B, Singh SB. Evaluation of anti-dengue activity of Carica papaya aqueous leaf extract and its role in platelet augmentation. Arch Virol 2019; 164:1095-1110. [PMID: 30790105 DOI: 10.1007/s00705-019-04179-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 01/17/2019] [Indexed: 12/16/2022]
Abstract
Dengue disease is characterized by a marked decrease in platelet count, which is life threatening. In the present study, we investigated the antiviral activity of an aqueous extract of Carica papaya leaves (PLE) against dengue virus (DENV) and its effect on platelet augmentation. The anti-dengue activity of PLE in DENV-infected THP-1 cells was examined by immunoblotting and flow cytometry. The effect of PLE on erythrocyte damage was investigated using hemolytic and anti-hemolytic assays. Virus-infected THP-1 cells were assayed for IFN-α secretion. The effect of PLE on platelet augmentation in rats with cyclophosphamide-induced thrombocytopenia was also investigated. The platelet count of blood from the retro-orbital plexus of rats was determined on the 1st, 4th, 7th, 11th and 14th day of study. On the 14th day, the rats were sacrificed for histopathological examination of the liver, kidney and spleen. Plasma of thrombocytopenic rats was tested for thrombopoietin (TPO) and IL-6 secretion. The data suggest that PLE significantly decreases the expression of the envelope and NS1 proteins in DENV-infected THP-1 cells. A marked decrease in intracellular viral load upon PLE treatment confirmed its antiviral activity. This also resulted in a significant decrease in erythrocyte damage and hydrogen-peroxide-induced lipid peroxidation. A significant increase in the number of platelets was found in thrombocytopenic rats treated with PLE, along with an increase in IL-6 and TPO levels. These findings suggest that PLE can potentially be used as an antiviral agent, as it helps in platelet augmentation and exhibits antiviral activity against DENV.
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Affiliation(s)
- Navita Sharma
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Kamla Prasad Mishra
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India. .,O/o Director General (Life Sciences), Defence Research and Development Organization, New Delhi, 110011, India.
| | - Sudipta Chanda
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Varun Bhardwaj
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Himanshi Tanwar
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Lilly Ganju
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Bhuvnesh Kumar
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
| | - Shashi Bala Singh
- Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Lucknow Road, Timarpur, New Delhi, Delhi, 110054, India
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Incorporation of NS1 and prM/M are important to confer effective protection of adenovirus-vectored Zika virus vaccine carrying E protein. NPJ Vaccines 2018; 3:29. [PMID: 30062066 PMCID: PMC6057874 DOI: 10.1038/s41541-018-0072-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 05/30/2018] [Accepted: 06/04/2018] [Indexed: 01/07/2023] Open
Abstract
Current design of Zika virus (ZIKV) vaccine mainly considered envelope (E) as the major target antigen. Non-structural protein NS1 was seldom considered. Herein, we generated three adenovirus-vectored vaccines carrying E (Ad2-E), or premembrane/membrane (prM/M) with E (Ad2-prME), or NS1 in addition to prM/M with E (Ad2-prME-NS1). Ad2-prME induced higher neutralizing antibody response to ZIKV than Ad2-E, suggesting prM/M is important for the folding of immunogenic E. Most intriguingly, Ad2-prME-NS1 elicited the best viral inhibition when the immune sera were added to ZIKV-infected cells. In ZIKV-challenged neonatal mice born to maternally immunized dams, Ad2-prME-NS1 conferred the best protection in preventing weight loss, neurological disorders, and viral replication. Ad2-prME also conferred significant protection but was less effective than Ad2-prME-NS1, whereas Ad2-E only alleviated neurological symptoms but did not inhibit viral replication. Our study suggested that NS1 should be considered in the design of ZIKV vaccine in addition to prM/M and E.
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28
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Dwivedi VD, Tripathi IP, Tripathi RC, Bharadwaj S, Mishra SK. Genomics, proteomics and evolution of dengue virus. Brief Funct Genomics 2018; 16:217-227. [PMID: 28073742 DOI: 10.1093/bfgp/elw040] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The genome of a pathogenic organism possesses a specific order of nucleotides that contains not only information about the synthesis and expression of proteomes, which are required for its growth and survival, but also about its evolution. Inhibition of any particular protein, which is required for the survival of that pathogenic organism, can be used as a potential therapeutic target for the development of effective drugs to treat its infections. In this review, the genomics, proteomics and evolution of dengue virus have been discussed, which will be helpful in better understanding of its origin, growth, survival and evolution, and may contribute toward development of new efficient anti-dengue drugs.
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Ricciardi-Jorge T, Bordignon J, Koishi A, Zanluca C, Mosimann AL, Duarte Dos Santos CN. Development of a quantitative NS1-capture enzyme-linked immunosorbent assay for early detection of yellow fever virus infection. Sci Rep 2017; 7:16229. [PMID: 29176643 PMCID: PMC5701136 DOI: 10.1038/s41598-017-16231-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 11/09/2017] [Indexed: 11/09/2022] Open
Abstract
Yellow fever is an arboviral disease that causes thousands of deaths every year in Africa and the Americas. However, few commercial diagnostic kits are available. Non-structural protein 1 (NS1) is an early marker of several flavivirus infections and is widely used to diagnose dengue virus (DENV) infection. Nonetheless, little is known about the dynamics of Yellow fever virus (YFV) NS1 expression and secretion, to encourage its use in diagnosis. To tackle this issue, we developed a quantitative NS1-capture ELISA specific for YFV using a monoclonal antibody and recombinant NS1 protein. This test was used to quantify NS1 in mosquito and human cell line cultures infected with vaccine and wild YFV strains. Our results showed that NS1 was detectable in the culture supernatants of both cell lines; however, a higher concentration was maintained as cell-associated rather than secreted into the extracellular milieu. A panel of 73 human samples was used to demonstrate the suitability of YFV NS1 as a diagnostic tool, resulting in 80% sensitivity, 100% specificity, a 100% positive predictive value and a 95.5% negative predictive value compared with RT-PCR. Overall, the developed NS1-capture ELISA showed potential as a promising assay for the detection of early YF infection.
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Affiliation(s)
- Taissa Ricciardi-Jorge
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba, Paraná, Brazil
| | - Juliano Bordignon
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba, Paraná, Brazil
| | - Andrea Koishi
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba, Paraná, Brazil
| | - Camila Zanluca
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba, Paraná, Brazil
| | - Ana Luiza Mosimann
- Laboratório de Virologia Molecular, Instituto Carlos Chagas, FIOCRUZ-PR, Curitiba, Paraná, Brazil
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Tarasuk M, Songprakhon P, Chimma P, Sratongno P, Na-Bangchang K, Yenchitsomanus PT. Alpha-mangostin inhibits both dengue virus production and cytokine/chemokine expression. Virus Res 2017; 240:180-189. [PMID: 28864423 DOI: 10.1016/j.virusres.2017.08.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/10/2017] [Accepted: 08/23/2017] [Indexed: 12/21/2022]
Abstract
Since severe dengue virus (DENV) infection in humans associates with both high viral load and massive cytokine production - referred to as "cytokine storm", an ideal drug for treatment of DENV infection should efficiently inhibit both virus production and cytokine expression. In searching for such an ideal drug, we discovered that α-mangostin (α-MG), a major bioactive compound purified from the pericarp of the mangosteen fruit (Garcinia mangostana Linn), which has been used in traditional medicine for several conditions including trauma, diarrhea, wound infection, pain, fever, and convulsion, inhibits both DENV production in cultured hepatocellular carcinoma HepG2 and Huh-7 cells, and cytokine/chemokine expression in HepG2 cells. α-MG could also efficiently inhibit all four serotypes of DENV. Treatment of DENV-infected cells with α-MG (20μM) significantly reduced the infection rates of four DENV serotypes by 47-55%. α-MG completely inhibited production of DENV-1 and DENV-3, and markedly reduced production of DENV-2 and DENV-4 by 100 folds. Furthermore, it could markedly reduce cytokine (IL-6 and TNF-α) and chemokine (RANTES, MIP-1β, and IP-10) transcription. These actions of α-MG are more potent than those of antiviral agent (ribavirin) and anti-inflammatory drug (dexamethasone). Thus, α-MG is potential to be further developed as therapeutic agent for DENV infection.
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Affiliation(s)
- Mayuri Tarasuk
- Graduate Program in Bioclinical Sciences, Chulabhorn International College of Medicine, Thammasat University, Pathumthani, 12121, Thailand
| | - Pucharee Songprakhon
- Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Pattamawan Chimma
- Research Division, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Center for Emerging and Neglected Infectious Disease, Mahidol University, Bangkok 73170, Thailand
| | - Panudda Sratongno
- Research Division, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Center for Emerging and Neglected Infectious Disease, Mahidol University, Bangkok 73170, Thailand
| | - Kesara Na-Bangchang
- Graduate Program in Bioclinical Sciences, Chulabhorn International College of Medicine, Thammasat University, Pathumthani, 12121, Thailand
| | - Pa-Thai Yenchitsomanus
- Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
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31
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Alcalá AC, Hernández-Bravo R, Medina F, Coll DS, Zambrano JL, del Angel RM, Ludert JE. The dengue virus non-structural protein 1 (NS1) is secreted from infected mosquito cells via a non-classical caveolin-1-dependent pathway. J Gen Virol 2017; 98:2088-2099. [DOI: 10.1099/jgv.0.000881] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Affiliation(s)
- Ana C. Alcalá
- Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), CDMX, Mexico
| | - Raiza Hernández-Bravo
- Exploration and Production Research Office, Mexican Petroleum Institute (IMP), Mexico City, Mexico
| | - Fernando Medina
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), CDMX, Mexico
| | - David S. Coll
- Center of Chemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Jose L. Zambrano
- Center of Microbiology and Cell Biology, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Rosa M. del Angel
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), CDMX, Mexico
| | - Juan E. Ludert
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), CDMX, Mexico
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32
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Routhu NK, Byrareddy SN. Host-Virus Interaction of ZIKA Virus in Modulating Disease Pathogenesis. J Neuroimmune Pharmacol 2017; 12:219-232. [PMID: 28349242 DOI: 10.1007/s11481-017-9736-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 03/03/2017] [Indexed: 01/08/2023]
Abstract
The Zika virus (ZIKV) is a newly emerging pathogen that has resulted in a worldwide epidemic. It primarily spreads either through infected Aedes aegypti or Aedes albopictus mosquitos leading to severe neurological disorders such as microcephaly and Guillain-Barré syndrome in susceptible individuals. The mode of ZIKV entry into specific cell types such as: epidermal keratinocytes, fibroblasts, immature dendritic cells (iDCs), and stem-cell-derived human neural progenitors has been determined through its major surface envelope glycoprotein. It has been known that oligosaccharides that are covalently linked to viral envelope proteins are crucial in defining host-virus interactions. However, the role of sugars/glycans in exploiting host-immune mechanisms and aiding receptor-mediated virus entry is not well defined. Therefore, this review focuses on host-pathogen interactions to better understand ZIKV pathogenesis.
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Affiliation(s)
- Nanda Kishore Routhu
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Siddappa N Byrareddy
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA. .,Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
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33
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Non-Canonical Roles of Dengue Virus Non-Structural Proteins. Viruses 2017; 9:v9030042. [PMID: 28335410 PMCID: PMC5371797 DOI: 10.3390/v9030042] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/06/2017] [Accepted: 03/08/2017] [Indexed: 12/15/2022] Open
Abstract
The Flaviviridae family comprises a number of human pathogens, which, although sharing structural and functional features, cause diseases with very different outcomes. This can be explained by the plurality of functions exerted by the few proteins coded by viral genomes, with some of these functions shared among members of a same family, but others being unique for each virus species. These non-canonical functions probably have evolved independently and may serve as the base to the development of specific therapies for each of those diseases. Here it is discussed what is currently known about the non-canonical roles of dengue virus (DENV) non-structural proteins (NSPs), which may account for some of the effects specifically observed in DENV infection, but not in other members of the Flaviviridae family. This review explores how DENV NSPs contributes to the physiopathology of dengue, evasion from host immunity, metabolic changes, and redistribution of cellular components during infection.
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34
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A Mutation Identified in Neonatal Microcephaly Destabilizes Zika Virus NS1 Assembly in Vitro. Sci Rep 2017; 7:42580. [PMID: 28198446 PMCID: PMC5309781 DOI: 10.1038/srep42580] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/12/2017] [Indexed: 12/11/2022] Open
Abstract
An unprecedented epidemic of Zika virus (ZIKV) infection had spread to South and Central America. ZIKV infection was recently confirmed by CDC (the Centers for Disease Control and Prevention) to cause neonatal microcephaly, which posed a significant public health emergency of international concern. No specific vaccines or drugs are currently available to fight ZIKV infection. ZIKV nonstructural protein 1 (NS1) plays an essential role in viral replication and immune evasion. We determined the crystal structure of ZIKV NS1172–352, which forms a head-to-head, symmetric dimer with a unique 14-stranded β-ladder conserved among flaviviruses. The assembly of the β-ladder dimer is concentration dependent. Strikingly, one pathogenic mutation T233A (NCBI accession no. KU527068), found in the brain tissue of infected fetus with neonatal microcephaly, is located at the dimer interface. Thr233, a unique residue found in ZIKV but not in other flaviviruses, organizes a central hydrogen bonding network at NS1 dimer interface. Mutation of Thr233 to Ala disrupts this elaborated interaction network, and destabilizes the NS1 dimeric assembly in vitro. In addition, our structural comparison of epitopes for protective antibody 22NS1, targeting West Nile Virus NS1, could potentially be valuable in understanding its anti-virus specificities and in the development of antibodies against ZIKV.
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Thiemmeca S, Tamdet C, Punyadee N, Prommool T, Songjaeng A, Noisakran S, Puttikhunt C, Atkinson JP, Diamond MS, Ponlawat A, Avirutnan P. Secreted NS1 Protects Dengue Virus from Mannose-Binding Lectin-Mediated Neutralization. THE JOURNAL OF IMMUNOLOGY 2016; 197:4053-4065. [PMID: 27798151 DOI: 10.4049/jimmunol.1600323] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 09/16/2016] [Indexed: 12/16/2022]
Abstract
Flavivirus nonstructural protein 1 (NS1) is a unique secreted nonstructural glycoprotein. Although it is absent from the flavivirus virion, intracellular and extracellular forms of NS1 have essential roles in viral replication and the pathogenesis of infection. The fate of NS1 in insect cells has been more controversial, with some reports suggesting it is exclusively cell associated. In this study, we confirm NS1 secretion from cells of insect origin and characterize its physical, biochemical, and functional properties in the context of dengue virus (DENV) infection. Unlike mammalian cell-derived NS1, which displays both high mannose and complex type N-linked glycans, soluble NS1 secreted from DENV-infected insect cells contains only high mannose glycans. Insect cell-derived secreted NS1 also has different physical properties, including smaller and more heterogeneous sizes and the formation of less stable NS1 hexamers. Both mammalian and insect cell-derived NS1 bind to complement proteins C1s, C4, and C4-binding protein, as well as to a novel partner, mannose-binding lectin. Binding of NS1 to MBL protects DENV against mannose-binding lectin-mediated neutralization by the lectin pathway of complement activation. As we detected secreted NS1 and DENV together in the saliva of infected Aedes aegypti mosquitoes, these findings suggest a mechanism of viral immune evasion at the very earliest phase of infection.
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Affiliation(s)
- Somchai Thiemmeca
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.,Graduate Program, Department of Immunology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Chamaiporn Tamdet
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Nuntaya Punyadee
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Tanapan Prommool
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand
| | - Adisak Songjaeng
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Sansanee Noisakran
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.,Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand
| | - Chunya Puttikhunt
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.,Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand
| | - John P Atkinson
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110.,Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110.,Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110.,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110; and
| | - Alongkot Ponlawat
- Department of Entomology, Armed Forces Research Institute of Medical Sciences, Bangkok 10400, Thailand
| | - Panisadee Avirutnan
- Division of Dengue Hemorrhagic Fever Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; .,Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 12120, Thailand
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Alayli F, Scholle F. Dengue virus NS1 enhances viral replication and pro-inflammatory cytokine production in human dendritic cells. Virology 2016; 496:227-236. [PMID: 27348054 DOI: 10.1016/j.virol.2016.06.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 06/06/2016] [Accepted: 06/10/2016] [Indexed: 12/31/2022]
Abstract
Dengue virus (DV) has become the most prevalent arthropod borne virus due to globalization and climate change. It targets dendritic cells during infection and leads to production of pro-inflammatory cytokines and chemokines. Several DV non-structural proteins (NS) modulate activation of human dendritic cells. We investigated the effect of DV NS1 on human monocyte-derived dendritic cells (mo-DCs) during dengue infection. NS1 is secreted into the serum of infected individuals where it interacts with various immune mediators and cell types. We purified secreted DV1 NS1 from supernatants of 293T cells that over-express the protein. Upon incubation with mo-DCs, we observed NS1 uptake and enhancement of early DV1 replication. As a consequence, mo-DCs that were pre-exposed to NS1 produced more pro-inflammatory cytokines in response to subsequent DV infection compared to DCs exposed to heat-inactivated NS1 (HNS1). Therefore the presence of exogenous NS1 is able to modulate dengue infection in mo-DCs.
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Affiliation(s)
- Farah Alayli
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Frank Scholle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA.
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Beatty PR, Puerta-Guardo H, Killingbeck SS, Glasner DR, Hopkins K, Harris E. Dengue virus NS1 triggers endothelial permeability and vascular leak that is prevented by NS1 vaccination. Sci Transl Med 2016; 7:304ra141. [PMID: 26355030 DOI: 10.1126/scitranslmed.aaa3787] [Citation(s) in RCA: 351] [Impact Index Per Article: 43.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The four dengue virus serotypes (DENV1 to DENV4) are mosquito-borne flaviviruses that cause up to ~100 million cases of dengue annually worldwide. Severe disease is thought to result from immunopathogenic processes involving serotype cross-reactive antibodies and T cells that together induce vasoactive cytokines, causing vascular leakage that leads to shock. However, no viral proteins have been directly implicated in triggering endothelial permeability, which results in vascular leakage. DENV nonstructural protein 1 (NS1) is secreted and circulates in patients' blood during acute infection; high levels of NS1 are associated with severe disease. We show that inoculation of mice with DENV NS1 alone induces both vascular leakage and production of key inflammatory cytokines. Furthermore, simultaneous administration of NS1 with a sublethal dose of DENV2 results in a lethal vascular leak syndrome. We also demonstrate that NS1 from DENV1, DENV2, DENV3, and DENV4 triggers endothelial barrier dysfunction, causing increased permeability of human endothelial cell monolayers in vitro. These pathogenic effects of physiologically relevant amounts of NS1 in vivo and in vitro were blocked by NS1-immune polyclonal mouse serum or monoclonal antibodies to NS1, and immunization of mice with NS1 from DENV1 to DENV4 protected against lethal DENV2 challenge. These findings add an important and previously overlooked component to the causes of dengue vascular leak, identify a new potential target for dengue therapeutics, and support inclusion of NS1 in dengue vaccines.
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Affiliation(s)
- P Robert Beatty
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA
| | - Henry Puerta-Guardo
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA
| | - Sarah S Killingbeck
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA
| | - Dustin R Glasner
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA
| | - Kaycie Hopkins
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA.
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Djossou F, Vesin G, Walter G, Epelboin L, Mosnier E, Bidaud B, Abboud P, Okandze A, Mattheus S, Elenga N, Demar M, Malvy D, Nacher M. Incidence and predictive factors of transaminase elevation in patients consulting for dengue fever in Cayenne Hospital, French Guiana. Trans R Soc Trop Med Hyg 2016; 110:134-40. [DOI: 10.1093/trstmh/trv117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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39
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Halstead SB. Comment on “Dengue virus NS1 protein activates cells via Toll-like receptor 4 and disrupts endothelial cell monolayer integrity” and “Dengue virus NS1 triggers endothelial permeability and vascular leak that is prevented by NS1 vaccination”. Sci Transl Med 2015; 7:318le4. [DOI: 10.1126/scitranslmed.aad4863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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40
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Scaturro P, Cortese M, Chatel-Chaix L, Fischl W, Bartenschlager R. Dengue Virus Non-structural Protein 1 Modulates Infectious Particle Production via Interaction with the Structural Proteins. PLoS Pathog 2015; 11:e1005277. [PMID: 26562291 PMCID: PMC4643051 DOI: 10.1371/journal.ppat.1005277] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 10/22/2015] [Indexed: 12/15/2022] Open
Abstract
Non-structural protein 1 (NS1) is one of the most enigmatic proteins of the Dengue virus (DENV), playing distinct functions in immune evasion, pathogenesis and viral replication. The recently reported crystal structure of DENV NS1 revealed its peculiar three-dimensional fold; however, detailed information on NS1 function at different steps of the viral replication cycle is still missing. By using the recently reported crystal structure, as well as amino acid sequence conservation, as a guide for a comprehensive site-directed mutagenesis study, we discovered that in addition to being essential for RNA replication, DENV NS1 is also critically required for the production of infectious virus particles. Taking advantage of a trans-complementation approach based on fully functional epitope-tagged NS1 variants, we identified previously unreported interactions between NS1 and the structural proteins Envelope (E) and precursor Membrane (prM). Interestingly, coimmunoprecipitation revealed an additional association with capsid, arguing that NS1 interacts via the structural glycoproteins with DENV particles. Results obtained with mutations residing either in the NS1 Wing domain or in the β-ladder domain suggest that NS1 might have two distinct functions in the assembly of DENV particles. By using a trans-complementation approach with a C-terminally KDEL-tagged ER-resident NS1, we demonstrate that the secretion of NS1 is dispensable for both RNA replication and infectious particle production. In conclusion, our results provide an extensive genetic map of NS1 determinants essential for viral RNA replication and identify a novel role of NS1 in virion production that is mediated via interaction with the structural proteins. These studies extend the list of NS1 functions and argue for a central role in coordinating replication and assembly/release of infectious DENV particles. Dengue virus (DENV) is a major arthropod-borne human pathogen, infecting more than 400 million individuals annually worldwide; however, neither a therapeutic drug nor a prophylactic vaccine is currently available. Amongst the DENV proteins, non-structural protein 1 (NS1) is one of the most enigmatic, being required for RNA replication, but also secreted from infected cells to counteract antiviral immune response, thus contributing to pathogenesis. Despite its essential role at early stages of the viral replication cycle, the molecular determinants governing NS1 functions are unknown. Here, we used a combination of genetic, high-resolution imaging and biochemical approaches and found that NS1 additionally plays an important role for the production of infectious virus particles. By using a novel trans-complementation system with fully functional epitope-tagged NS1, we show that NS1 interacts with the structural proteins residing in the envelope of the virus particle. An NS1 variant retained in the endoplasmic reticulum still supported efficient DENV particle production, demonstrating that secretion of NS1 is dispensable for virion production. This study expands the list of functions exerted by NS1 for the DENV replication cycle. Given this multi-functional nature, NS1 appears to be an attractive target for antiviral therapy.
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Affiliation(s)
- Pietro Scaturro
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
- * E-mail: (PS); (RB)
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Laurent Chatel-Chaix
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Wolfgang Fischl
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
- * E-mail: (PS); (RB)
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Deshmukh JM, Avachat S, Fating A. DENGUE WITH ATYPICAL MANIFESTATIONS AND WHO CLASSIFICATION. ACTA ACUST UNITED AC 2015. [DOI: 10.18410/jebmh/2015/820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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De La Cruz Hernández SI, Reyes-del Valle J, Villegas-del Angel E, Ludert JE, del Angel RM. Dengue laboratory diagnosis: still some room for improvement. Future Virol 2015. [DOI: 10.2217/fvl.15.59] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dengue is the most important and widely distributed arthropod-borne viral disease affecting humans. The number of dengue virus infections has steadily grown and more than 100 countries survey dengue incidence every year. Due to the lack of an approved antiviral treatment or licensed preventative vaccine, accurate and opportune diagnosis is commended for efficient dengue epidemiological surveillance, to propose control measures in order to curtail outbreaks timely and treat patients satisfactorily. In this review, the basis, application and indications for different diagnostic tests are described, and their advantages and limitations considered. At the end of this piece, we speculate what the future may hold for the diagnosis of dengue infections.
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Affiliation(s)
- Sergio Isaac De La Cruz Hernández
- Department of Virology, Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE), Mexico
- Departament of Infectomics & Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), D.F., Mexico
| | | | | | - Juan E Ludert
- Departament of Infectomics & Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), D.F., Mexico
| | - Rosa M del Angel
- Departament of Infectomics & Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), D.F., Mexico
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Dalrymple NA, Mackow ER. Virus interactions with endothelial cell receptors: implications for viral pathogenesis. Curr Opin Virol 2014; 7:134-40. [PMID: 25063986 PMCID: PMC4206553 DOI: 10.1016/j.coviro.2014.06.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 06/10/2014] [Accepted: 06/27/2014] [Indexed: 01/14/2023]
Abstract
The endothelial lining of the vasculature performs a vital role in maintaining fluid barrier functions despite balancing nutrient and fluid content of tissues, repairing localized damage, coordinating responses of a plethora of factors, immune cells and platelets through a multitude of endothelial cell surface receptors. Viruses that nonlytically cause lethal hemorrhagic or edematous diseases engage receptors on vascular and lymphatic endothelial cells, altering normal cellular responses that control capillary leakage and fluid clearance functions with lethal consequences. Recent studies indicate that receptors directing dengue virus and hantavirus infection of the endothelium contribute to the dysregulation of normal endothelial cell signaling responses that control capillary permeability and immune responses that contribute to pathogenesis. Here we present recent studies of virally altered endothelial functions that provide new insight into targeting barrier functions of the endothelium as a potential therapeutic approach.
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Crook KR, Miller-Kittrell M, Morrison CR, Scholle F. Modulation of innate immune signaling by the secreted form of the West Nile virus NS1 glycoprotein. Virology 2014; 458-459:172-82. [PMID: 24928049 DOI: 10.1016/j.virol.2014.04.036] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 03/17/2014] [Accepted: 04/22/2014] [Indexed: 12/28/2022]
Abstract
West Nile virus (WNV) employs several different strategies to escape the innate immune response. We have previously demonstrated that the WNV NS1 protein interferes with signal transduction from Toll-like receptor 3 (TLR3). NS1 is a glycoprotein that can be found intracellularly or associated with the plasma membrane. In addition, NS1 is secreted to high levels during flavivirus infections. We investigated whether the secreted form of NS1 inhibits innate immune signaling pathways in uninfected cells. Secreted NS1 (sNS1) was purified from supernatants of cells engineered to express the protein. Purified sNS1 associated with and repressed TLR3-induced cytokine production by HeLa cells, and inhibited signaling from TLR3 and other TLRs in bone marrow-derived macrophages and dendritic cells. Footpad administration of sNS1 showed the protein associated predominantly with macrophages and dendritic cells in the draining lymph node. Additionally, sNS1 significantly reduced TLR3 signaling and WNV replicon particle-mediated cytokine transcription in popliteal lymph nodes.
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Affiliation(s)
- Kristen R Crook
- Department of Biological Sciences, North Carolina State University, Raleigh, NC CB7614, USA
| | - Mindy Miller-Kittrell
- Department of Biological Sciences, North Carolina State University, Raleigh, NC CB7614, USA
| | - Clayton R Morrison
- Department of Biological Sciences, North Carolina State University, Raleigh, NC CB7614, USA
| | - Frank Scholle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC CB7614, USA.
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Morrison CR, Scholle F. Abrogation of TLR3 inhibition by discrete amino acid changes in the C-terminal half of the West Nile virus NS1 protein. Virology 2014; 456-457:96-107. [PMID: 24889229 DOI: 10.1016/j.virol.2014.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/10/2014] [Accepted: 03/16/2014] [Indexed: 01/14/2023]
Abstract
West Nile virus (WNV) is a mosquito-transmitted pathogen, which causes significant disease in humans. The innate immune system is a first-line defense against invading microorganism and many flaviviruses, including WNV, have evolved multifunctional proteins, which actively suppress its activation and antiviral actions. The WNV non-structural protein 1 (NS1) inhibits signal transduction originating from Toll-like receptor 3 (TLR3) and also critically contributes to virus genome replication. In this study we developed a novel FACS-based screen to attempt to separate these two functions. The individual amino acid changes P320S and M333V in NS1 restored TLR3 signaling in virus-infected HeLa cells. However, virus replication was also attenuated, suggesting that the two functions are not easily separated and may be contained within overlapping domains. The residues we identified are completely conserved among several mosquito- and tick-borne flaviviruses, indicating that they are of biological importance to the virus.
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Affiliation(s)
- Clayton R Morrison
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Frank Scholle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA.
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Abstract
The Flavivirus nonstructural protein 1 (NS1) is a conserved, membrane-associated and secreted glycoprotein with replication and immune evasion functions. Secreted NS1 is a hexameric, barrel-shaped lipoprotein that can bind back to the plasma membrane of cells. Antibodies targeting cell surface-associated NS1 can be protective in vivo in a manner dependent on Fc effector functions. We describe here the crystal structure of a C-terminal fragment (residues 172-352) of West Nile (WNV) and Dengue virus NS1 proteins at 1.85 and 2.7 Å resolution, respectively. NS1(172-352) assembles as a unique rod-shaped dimer composed of a 16-stranded β-platform flanked on one face by protruding connecting loops. We also determined the 3.0 Å resolution structure of WNV NS1(172-352) with the protective 22NS1 antibody Fab, which engages the loop-face of the rod. The head-to-head NS1(172-352) dimer we observe in crystal lattices is supported by multiangle light and small-angle X-ray scattering studies. We used the available cryo-electron microscopy reconstruction to develop a pseudoatomic model of the NS1 hexamer. The model was constructed with the NS1(172-352) dimeric rod aligned with the long axis of the barrel, and with the loop-face oriented away from the core. Difference densities suggest that the N-terminal region of NS1 forms globular lobes that mediate lateral contacts between dimers in the hexamer. Our model also suggests that the N-terminal lobe forms the surface of the central cavity where lipid binding may occur.
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Poungpair O, Bangphoomi K, Chaowalit P, Sawasdee N, Saokaew N, Choowongkomon K, Chaicumpa W, Yenchitsomanus PT. Generation of human single-chain variable fragment antibodies specific to dengue virus non-structural protein 1 that interfere with the virus infectious cycle. MAbs 2014; 6:474-82. [PMID: 24492300 DOI: 10.4161/mabs.27874] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Severe forms of dengue virus (DENV) infection frequently cause high case fatality rate. Currently, there is no effective vaccine against the infection. Clinical cases are given only palliative treatment as specific anti-DENV immunotherapy is not available and it is urgently required. In this study, human single-chain variable fragment (HuScFv) antibodies that bound specifically to the conserved non-structural protein-1 (NS1) of DENV and interfered with the virus replication cycle were produced by using phage display technology. Recombinant NS1 (rNS1) of DENV serotype 2 (DENV2) was used as antigen in phage bio-panning to select phage clones that displayed HuScFv from antibody phage display library. HuScFv from two phagemid transformed E. coli clones, i.e., clones 11 and 13, bound to the rNS1 as well as native NS1 in both secreted and intracellular forms. Culture fluids of the HuScFv11/HuScFv13 exposed DENV2 infected cells had significant reduction of the infectious viral particles, implying that the antibody fragments affected the virus morphogenesis or release. HuScFv epitope mapping by phage mimotope searching revealed that HuScFv11 bound to amino acids 1-14 of NS1, while the HuScFv13 bound to conformational epitope at the C-terminal portion of the NS1. Although the functions of the epitopes and the molecular mechanism of the HuScFv11 and HuScFv13 require further investigations, these small antibodies have high potential for development as anti-DENV biomolecules.
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Affiliation(s)
- Ornnuthchar Poungpair
- Division of Molecular Medicine; Department of Research and Development; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
| | - Kunan Bangphoomi
- Department of Biochemistry; Faculty of Sciences; Kasetsart University; Bangkok, Thailand
| | - Prapaipit Chaowalit
- Division of Molecular Medicine; Department of Research and Development; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
| | - Nunghathai Sawasdee
- Division of Molecular Medicine; Department of Research and Development; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
| | - Nichapatr Saokaew
- Immunology Graduate Program; Department of Immunology; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
| | | | - Wanpen Chaicumpa
- Laboratory for Research and Technology Development; Department of Parasitology; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
| | - Pa-thai Yenchitsomanus
- Division of Molecular Medicine; Department of Research and Development; Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok, Thailand
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Youn S, Ambrose RL, Mackenzie JM, Diamond MS. Non-structural protein-1 is required for West Nile virus replication complex formation and viral RNA synthesis. Virol J 2013; 10:339. [PMID: 24245822 PMCID: PMC3842638 DOI: 10.1186/1743-422x-10-339] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 11/14/2013] [Indexed: 11/18/2022] Open
Abstract
Background Flavivirus NS1 is a non-structural glycoprotein that is expressed on the cell surface and secreted into the extracellular space, where it acts as an antagonist of complement pathway activation. Despite its transit through the secretory pathway and intracellular localization in the lumen of the endoplasmic reticulum and Golgi vesicles, NS1 is as an essential gene for flavivirus replication. How NS1 modulates infection remains uncertain given that the viral RNA replication complex localizes to the cytosolic face of the endoplasmic reticulum. Methods and Results Using a trans-complementation assay, we show that viruses deleted for NS1 (∆-NS1) can be rescued by transgenic expression of NS1 from West Nile virus (WNV) or heterologous flaviviruses in the absence of adaptive mutations. In viral lifecycle experiments, we demonstrate that WNV NS1 was not required for virus attachment or input strand translation of the infectious viral RNA, but was necessary for negative and positive strand RNA synthesis and formation of the endoplasmic reticulum-associated replication complex. Conclusions WNV RNA lacking intact NS1 genes was efficiently translated but failed to form canonical replication complexes at early times after infection, which resulted in an inability to replicate viral RNA. These results expand on prior studies with yellow fever and Kunjin viruses to show that flavivirus NS1 has an essential co-factor role in regulating replication complex formation and viral RNA synthesis.
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Affiliation(s)
| | | | | | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.
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