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Naveed A, Eertink LG, Wang D, Li F. Lessons Learned from West Nile Virus Infection:Vaccinations in Equines and Their Implications for One Health Approaches. Viruses 2024; 16:781. [PMID: 38793662 PMCID: PMC11125849 DOI: 10.3390/v16050781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024] Open
Abstract
Humans and equines are two dead-end hosts of the mosquito-borne West Nile virus (WNV) with similar susceptibility and pathogenesis. Since the introduction of WNV vaccines into equine populations of the United States of America (USA) in late 2002, there have been only sporadic cases of WNV infection in equines. These cases are generally attributed to unvaccinated and under-vaccinated equines. In contrast, due to the lack of a human WNV vaccine, WNV cases in humans have remained steadily high. An average of 115 deaths have been reported per year in the USA since the first reported case in 1999. Therefore, the characterization of protective immune responses to WNV and the identification of immune correlates of protection in vaccinated equines will provide new fundamental information about the successful development and evaluation of WNV vaccines in humans. This review discusses the comparative epidemiology, transmission, susceptibility to infection and disease, clinical manifestation and pathogenesis, and immune responses of WNV in humans and equines. Furthermore, prophylactic and therapeutic strategies that are currently available and under development are described. In addition, the successful vaccination of equines against WNV and the potential lessons for human vaccine development are discussed.
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Affiliation(s)
| | | | | | - Feng Li
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546, USA; (A.N.); (L.G.E.); (D.W.)
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Rivas J, Dubois A, Blanquer A, Gérardy M, Ziegler U, Groschup MH, Grobet L, Garigliany MM. Tendon-Derived Mesenchymal Stem Cells (TDSCs) as an In Vitro Model for Virological Studies in Wild Birds. Viruses 2023; 15:1455. [PMID: 37515142 PMCID: PMC10383174 DOI: 10.3390/v15071455] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
The use of wild animals in research is complicated due to the capture and housing conditions, as well as to legal aspects, making it difficult to develop in vivo and in vitro models for the study of pathologies that affect these species. Here we validate an in vitro model of tendon-derived mesenchymal cells (TDSC) from Eurasian blackbird (Turdus merula) cadaveric samples. Through the expression of surface markers and the ability to differentiate into multiple lineages, the nature of the cells was confirmed. We then evaluated Mesenchymal Stem Cells (MSCs) as an infection model for the Usutu Flavivirus. To this aim, blackbird TDSCs were compared to Vero E6 cells, commonly used in Flavivirus studies. Both cells showed permissiveness to USUV infection as confirmed by immunocytochemistry. Moreover, TDSCs exhibited replication kinetics similar to, although slightly lower than, Vero E6, confirming these cells as a pertinent study model for the study of the pathogenesis of USUV. In this work, we isolated and characterized tendon-derived mesenchymal stem cells, which represent an interesting and convenient in vitro model for the study of wildlife species in laboratories.
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Affiliation(s)
- José Rivas
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Pathology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (J.R.); (A.B.); (M.G.)
| | - Axel Dubois
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Embryology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (A.D.); (L.G.)
| | - Aude Blanquer
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Pathology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (J.R.); (A.B.); (M.G.)
| | - Mazarine Gérardy
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Pathology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (J.R.); (A.B.); (M.G.)
| | - Ute Ziegler
- Institute for Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (U.Z.); (M.H.G.)
| | - Martin H. Groschup
- Institute for Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (U.Z.); (M.H.G.)
| | - Luc Grobet
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Embryology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (A.D.); (L.G.)
| | - Mutien-Marie Garigliany
- Fundamental and Applied Research for Animals & Health (FARAH), Laboratory of Pathology, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; (J.R.); (A.B.); (M.G.)
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Talmi-Frank D, Byas AD, Murrieta R, Weger-Lucarelli J, Rückert C, Gallichotte EN, Yoshimoto JA, Allen C, Bosco-Lauth AM, Graham B, Felix TA, Brault AC, Ebel GD. Intracellular Diversity of WNV within Circulating Avian Peripheral Blood Mononuclear Cells Reveals Host-Dependent Patterns of Polyinfection. Pathogens 2023; 12:767. [PMID: 37375457 DOI: 10.3390/pathogens12060767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
Arthropod-borne virus (arbovirus) populations exist as mutant swarms that are maintained between arthropods and vertebrates. West Nile virus (WNV) population dynamics are host-dependent. In American crows, purifying selection is weak and population diversity is high compared to American robins, which have 100- to 1000-fold lower viremia. WNV passed in robins leads to fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows for higher genetic diversity within individual avian peripheral blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed host-specific differences in genetic diversity and fitness. Specifically, we infected cells and birds with a molecularly barcoded WNV and sequenced viral RNA from single cells to quantify the number of WNV barcodes in each. Our results demonstrate that the richness of WNV populations within crows far exceeds that in robins. Similarly, rare WNV variants were maintained by crows more frequently than by robins. Our results suggest that increased viremia in crows relative to robins leads to the maintenance of defective genomes and less prevalent variants, presumably through complementation. Our findings further suggest that weaker purifying selection in highly susceptible crows is attributable to this higher viremia, polyinfections and complementation.
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Affiliation(s)
- Dalit Talmi-Frank
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Alex D Byas
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Reyes Murrieta
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - James Weger-Lucarelli
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Claudia Rückert
- Department of Biochemistry and Molecular Biology, College of Agriculture, Biotechnology & Natural Resources, University of Nevada, Reno, NV 89557, USA
| | - Emily N Gallichotte
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Janna A Yoshimoto
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Chris Allen
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Angela M Bosco-Lauth
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Barbara Graham
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Todd A Felix
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Lakewood, CO 80228, USA
| | - Aaron C Brault
- Division of Vector-Borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | - Gregory D Ebel
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
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Frank DT, Byas AD, Murrieta R, Weger-Lucarelli J, Rückert C, Gallichotte E, Yoshimoto JA, Allen C, Bosco-Lauth AM, Graham B, Felix TA, Brault A, Ebel GD. Intracellular diversity of WNV within circulating avian peripheral blood mononuclear cells reveals host-dependent patterns of polyinfection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.27.525959. [PMID: 36747638 PMCID: PMC9900929 DOI: 10.1101/2023.01.27.525959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Error-prone replication of RNA viruses generates the genetic diversity required for adaptation within rapidly changing environments. Thus, arthropod-borne virus (arbovirus) populations exist in nature as mutant swarms that are maintained between arthropods and vertebrates. Previous studies have demonstrated that West Nile virus (WNV) population dynamics are host dependent: In American crows, which experience extremely high viremia, purifying selection is weak and population diversity is high compared to American robins, which have 100 to 1000-fold lower viremia. WNV passed in robins experiences fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows higher genetic diversity within individual avian peripheral-blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed host-specific differences in genetic diversity and fitness. Specifically, we infected cells and birds with a novel, barcoded version of WNV and sequenced viral RNA from single cells to quantify the number of WNV barcodes that each contained. Our results demonstrate that the richness of WNV populations within crows far exceeds that in robins. Similarly, rare WNV variants were maintained by crows more frequently than by robins. Our results suggest that increased viremia in crows relative to robins leads to maintenance of defective genomes and less prevalent variants, presumably through complementation. Our findings further suggest that weaker purifying selection in highly susceptible crows is attributable to this higher viremia, polyinfections and complementation. These studies further document the role of particular, ecologically relevant hosts in shaping virus population structure. Author Summary WNV mutational diversity in vertebrates is species-dependent. In crows, low frequency variants are common, and viral populations are more diverse. In robins, fewer mutations become permanent fixtures of the overall viral population. We infected crows, robins and a chicken cell line with a genetically marked (barcoded) WNV. Higher levels of virus led to multiple unique WNV genomes infecting individual cells, even when a genotype was present at low levels in the input viral stock. Our findings suggest that higher levels of circulating virus in natural hosts allow less fit viruses to survive in RNA virus populations through complementation by more fit viruses. This is significant as it allows less represented and less fit viruses to be maintained at low levels until they potentially emerge when virus environments change. Overall our data reveal new insights on the relationships between host susceptibility to high viremia and virus evolution.
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Affiliation(s)
- Dalit Talmi Frank
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Alex D. Byas
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Reyes Murrieta
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - James Weger-Lucarelli
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Claudia Rückert
- Department of Biochemistry and Molecular Biology, College of Agriculture, Biotechnology & Natural Resources, University of Nevada, Reno, Nevada, USA
| | - Emily Gallichotte
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Janna A. Yoshimoto
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Chris Allen
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Angela M. Bosco-Lauth
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Barbara Graham
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Todd A. Felix
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Golden, CO, USA
| | - Aaron Brault
- Division of Vector-borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention Fort Collins, Colorado, USA
| | - Gregory D. Ebel
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
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Tembusu Virus entering the central nervous system caused nonsuppurative encephalitis without disrupting the blood-brain barrier. J Virol 2021; 95:JVI.02191-20. [PMID: 33472933 PMCID: PMC8092698 DOI: 10.1128/jvi.02191-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Tembusu Virus (TMUV) is an emerging and re-emerging zoonotic pathogen that adversely affects poultry industry in recent years. TMUV disease is characterized by nonsuppurative encephalitis in ducklings. The duckling infection model was established to study the mechanism of TMUV crossing the blood-brain barrier (BBB) into the central nervous system (CNS). Here, we showed that no obvious clinical symptoms and enhancement of BBB permeability occurred at the early stage of infection (3∼5 dpi). While simultaneously virus particles were observed by transmission electron microscopy in the brain, inducing the accumulation of inflammatory cytokines. Neurological symptoms and disruption of BBB appeared at the intermediate stage of infection (7∼9 dpi). It was confirmed that TMUV could survive and propagate in brain microvascular endothelial cells (BMECs), but did not affect the permeability of BBB in vivo and in vitro at an early date. In conclusion, TMUV enters the CNS then causes encephalitis, and finally destruct the BBB, which may be due to the direct effect of TMUV on BMECs and the subsequent response of "inflammatory storm".IMPORTANCE The TMUV disease has caused huge losses to the poultry industry in Asia, which is potentially harmful to public health. Neurological symptoms and their sequelae are the main characters of this disease. However, the mechanism of how this virus enters the brain and causes encephalitis is unclear. In this study, we confirmed that the virus entered the CNS and then massively destroyed BBB and the BBB damage was closely associated with the subsequent outbreak of inflammation. TMUV may enter the CNS through the transcellular and "Trojan horse" pathways. These findings can fill the knowledge gap in the pathogenesis of TMUV-infected poultry and be benefit for the treatment of TMUV disease. What's more, TMUV is a representative to study the infection of avian flavivirus. Therefore, our studies have significances both for understanding of the full scope of mechanisms of TMUV and other flavivirus infection, and conceivably, for therapeutics.
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Therapeutic role of inflammasome inhibitors in neurodegenerative disorders. Brain Behav Immun 2021; 91:771-783. [PMID: 33157255 DOI: 10.1016/j.bbi.2020.11.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 10/30/2020] [Accepted: 11/01/2020] [Indexed: 12/16/2022] Open
Abstract
Neuroinflammation, characterized by the activation of glial cells, is a hallmark in several neurological and neurodegenerative disorders. Inadequate inflammation cannot eliminate the infection of pathogens, while excessive or hyper-reactive inflammation can cause chronic or systemic inflammatory diseases affecting the central nervous system (CNS). In response to a brain injury or pathogen invasion, the pathogen recognition receptors (PRRs) expressed on glial cells are activated via binding to cellular damage-associated molecular patterns (DAMPs) or pathogen-associated molecular patterns (PAMPs). This subsequently leads to the activation of NOD (nucleotide-binding oligomerization domain)-like receptor proteins (NLRs). In neurodegenerative diseases such as HIV-1-associated neurocognitive disorders (HAND), Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS), chronic inflammation is a critical contributing factor for disease manifestation including pathogenesis. Emerging evidence points to the involvement of "inflammasomes", especially the nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing (NLRP) complex in the development of these diseases. The activated NLRP3 results in the proteolytic activation of caspase-1 that facilitates the cleavage of pro-IL-1β and the secretion of IL-1β and IL-18 proinflammatory cytokines. Accordingly, these and other seminal findings have led to the development of NLRP-targeting small-molecule therapeutics as possible treatment options for neurodegenerative disorders. In this review, we will discuss the new advances and evidence-based literature concerning the role of inflammasomes in neurodegenerative diseases, its role in the neurological repercussions of CNS chronic infection, and the examples of preclinical or clinically tested NLRP inhibitors as potential strategies for the treatment of chronic neurological diseases.
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McDonald EM, Anderson J, Wilusz J, Ebel GD, Brault AC. Zika Virus Replication in Myeloid Cells during Acute Infection Is Vital to Viral Dissemination and Pathogenesis in a Mouse Model. J Virol 2020; 94:e00838-20. [PMID: 32847848 PMCID: PMC7565634 DOI: 10.1128/jvi.00838-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 08/02/2020] [Indexed: 12/22/2022] Open
Abstract
Zika virus (ZIKV) can establish infection in immune privileged sites such as the testes, eye, and placenta. Whether ZIKV infection of white blood cells is required for dissemination of the virus to immune privileged sites has not been definitively shown. To assess whether initial ZIKV replication in myeloid cell populations is critical for dissemination during acute infection, recombinant ZIKVs were generated that could not replicate in these specific cells. ZIKV was cell restricted by insertion of a complementary sequence to a myeloid-specific microRNA in the 3' untranslated region. Following inoculation of a highly sensitive immunodeficient mouse model, crucial immune parameters, such as quantification of leukocyte cell subsets, cytokine and chemokine secretion, and viremia, were assessed. Decreased neutrophil numbers in the spleen were observed during acute infection with myeloid-restricted ZIKV that precluded the generation of viremia and viral dissemination to peripheral organs. Mice inoculated with a nontarget microRNA control ZIKV demonstrated increased expression of key cytokines and chemokines critical for neutrophil and monocyte recruitment and increased neutrophil influx in the spleen. In addition, ZIKV-infected Ly6Chi monocytes were identified in vivo in the spleen. Mice inoculated with myeloid-restricted ZIKV had a decrease in Ly6Chi ZIKV RNA-positive monocytes and a lack of inflammatory cytokine production compared to mice inoculated with control ZIKV.IMPORTANCE Myeloid cells, including monocytes, play a crucial role in immune responses to pathogens. Monocytes have also been implicated as "Trojan horses" during viral infections, carrying infectious virus particles to immune privileged sites and/or to sites protected by physical blood-tissue barriers, such as the blood-testis barrier and the blood-brain barrier. In this study, we found that myeloid cells are crucial to Zika virus (ZIKV) pathogenesis. By engineering ZIKV clones to encode myeloid-specific microRNA target sequences, viral replication was inhibited in myeloid cells by harnessing the RNA interference pathway. Severely immunodeficient mice inoculated with myeloid-restricted ZIKV did not demonstrate clinical signs of disease and survived infection. Furthermore, viral dissemination to peripheral organs was not observed in these mice. Lastly, we identified Ly6Cmid/hi murine monocytes as the major myeloid cell population that disseminates ZIKV.
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Affiliation(s)
- Erin M McDonald
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, USA
| | - John Anderson
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Jeff Wilusz
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Gregory D Ebel
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Aaron C Brault
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, USA
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West Nile Virus: An Update on Pathobiology, Epidemiology, Diagnostics, Control and "One Health" Implications. Pathogens 2020; 9:pathogens9070589. [PMID: 32707644 PMCID: PMC7400489 DOI: 10.3390/pathogens9070589] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/16/2020] [Accepted: 07/16/2020] [Indexed: 02/06/2023] Open
Abstract
West Nile virus (WNV) is an important zoonotic flavivirus responsible for mild fever to severe, lethal neuroinvasive disease in humans, horses, birds, and other wildlife species. Since its discovery, WNV has caused multiple human and animal disease outbreaks in all continents, except Antarctica. Infections are associated with economic losses, mainly due to the cost of treatment of infected patients, control programmes, and loss of animals and animal products. The pathogenesis of WNV has been extensively investigated in natural hosts as well as in several animal models, including rodents, lagomorphs, birds, and reptiles. However, most of the proposed pathogenesis hypotheses remain contentious, and much remains to be elucidated. At the same time, the unavailability of specific antiviral treatment or effective and safe vaccines contribute to the perpetuation of the disease and regular occurrence of outbreaks in both endemic and non-endemic areas. Moreover, globalisation and climate change are also important drivers of the emergence and re-emergence of the virus and disease. Here, we give an update of the pathobiology, epidemiology, diagnostics, control, and “One Health” implications of WNV infection and disease.
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Peng BH, Wang T. West Nile Virus Induced Cell Death in the Central Nervous System. Pathogens 2019; 8:pathogens8040215. [PMID: 31683807 PMCID: PMC6963722 DOI: 10.3390/pathogens8040215] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/30/2019] [Accepted: 10/30/2019] [Indexed: 12/21/2022] Open
Abstract
West Nile virus (WNV), a mosquito-borne, single-stranded flavivirus, has caused annual outbreaks of viral encephalitis in the United States since 1999. The virus induces acute infection with a clinical spectrum ranging from a mild flu-like febrile symptom to more severe neuroinvasive conditions, including meningitis, encephalitis, acute flaccid paralysis, and death. Some WNV convalescent patients also developed long-term neurological sequelae. Neither the treatment of WNV infection nor an approved vaccine is currently available for humans. Neuronal death in the central nervous system (CNS) is a hallmark of WNV-induced meningitis and encephalitis. However, the underlying mechanisms of WNV-induced neuronal damage are not well understood. In this review, we discuss current findings from studies of WNV infection in vitro in the CNS resident cells and the in vivo animal models, and provide insights into WNV-induced neuropathogenesis.
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Affiliation(s)
- Bi-Hung Peng
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Tian Wang
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Carlin AF, Wen J, Vizcarra EA, McCauley M, Chaillon A, Akrami K, Kim C, Ngono AE, Lara-Marquez ML, Smith DM, Glass CK, Schooley RT, Benner C, Shresta S. A longitudinal systems immunologic investigation of acute Zika virus infection in an individual infected while traveling to Caracas, Venezuela. PLoS Negl Trop Dis 2018; 12:e0007053. [PMID: 30596671 PMCID: PMC6329527 DOI: 10.1371/journal.pntd.0007053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 01/11/2019] [Accepted: 12/05/2018] [Indexed: 12/29/2022] Open
Abstract
Zika virus (ZIKV) is an emerging mosquito-borne flavivirus linked to devastating neurologic diseases. Immune responses to flaviviruses may be pathogenic or protective. Our understanding of human immune responses to ZIKV in vivo remains limited. Therefore, we performed a longitudinal molecular and phenotypic characterization of innate and adaptive immune responses during an acute ZIKV infection. We found that innate immune transcriptional and genomic responses were both cell type- and time-dependent. While interferon stimulated gene induction was common to all innate immune cells, the upregulation of important inflammatory cytokine genes was primarily limited to monocyte subsets. Additionally, genomic analysis revealed substantial chromatin remodeling at sites containing cell-type specific transcription factor binding motifs that may explain the observed changes in gene expression. In this dengue virus-experienced individual, adaptive immune responses were rapidly mobilized with T cell transcriptional activity and ZIKV neutralizing antibody responses peaking 6 days after the onset of symptoms. Collectively this study characterizes the development and resolution of an in vivo human immune response to acute ZIKV infection in an individual with pre-existing flavivirus immunity. Zika virus (ZIKV) is an emerging flaviviral infection that causes significant clinical disease. It is estimated that approximately one half of the world’s population is at risk for ZIKV infection. There are only a limited number of studies describing the human immune response to ZIKV infection. Carlin et al. combined conventional and genomic approaches to longitudinally analyze the innate and adaptive immune responses to acute ZIKV infection and its resolution in a person who was infected while traveling in Venezuela during the 2016 ZIKV epidemic year. Genome-wide sequencing in individual cell types revealed that although many populations respond to interferon stimulation, only specific cell populations within peripheral blood mononuclear cells upregulate important inflammatory cytokine gene expression. Additionally, analysis of open chromatin using ATAC-seq suggests that chromatin remodeling at sites containing cell-type specific transcription factor binding motifs may help us understand changes in gene expression. Consistent with previous reports, this individual with prior exposure to dengue virus (DENV), rapidly developed neutralizing anti-ZIKV responses that were cross-reactive with multiple DENV serotypes. Collectively this study combines traditional and genomic approaches to characterize the cell-type specific development of an in vivo human immune response to acute ZIKV infection.
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Affiliation(s)
- Aaron F. Carlin
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- * E-mail: (AFC); (SS)
| | - Jinsheng Wen
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
| | - Edward A. Vizcarra
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
| | - Melanie McCauley
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
| | - Antoine Chaillon
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- Veterans Affairs San Diego Healthcare System, San Diego, California, United States of America
| | - Kevan Akrami
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Cheryl Kim
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
| | - Annie Elong Ngono
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
| | - Maria Luz Lara-Marquez
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Davey M. Smith
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- Veterans Affairs San Diego Healthcare System, San Diego, California, United States of America
| | - Christopher K. Glass
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Robert T. Schooley
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Christopher Benner
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Sujan Shresta
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, United States of America
- Division of Inflammation Biology, La Jolla Institute for Immunology, La Jolla, California, United States of America
- * E-mail: (AFC); (SS)
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11
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Kosch R, Delarocque J, Claus P, Becker SC, Jung K. Gene expression profiles in neurological tissues during West Nile virus infection: a critical meta-analysis. BMC Genomics 2018; 19:530. [PMID: 30001706 PMCID: PMC6044103 DOI: 10.1186/s12864-018-4914-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/02/2018] [Indexed: 02/05/2023] Open
Abstract
Background Infections with the West Nile virus (WNV) can attack neurological tissues in the host and alter gene expression levels therein. Several individual studies have analyzed these changes in the transcriptome based on measurements with DNA microarrays. Individual microarray studies produce a high-dimensional data structure with the number of studied genes exceeding the available sample size by far. Therefore, the level of scientific evidence of these studies is rather low and results can remain uncertain. Furthermore, the individual studies concentrate on different types of tissues or different time points after infection. A general statement regarding the transcriptional changes through WNV infection in neurological tissues is therefore hard to make. We screened public databases for transcriptome expression studies related to WNV infections and used different analysis pipelines to perform meta-analyses of these data with the goal of obtaining more stable results and increasing the level of evidence. Results We generated new lists of genes differentially expressed between WNV infected neurological tissues and control samples. A comparison with these genes to findings of a meta-analysis of immunological tissues is performed to figure out tissue-specific differences. While 5.879 genes were identified exclusively in the neurological tissues, 15 genes were found exclusively in the immunological tissues, and 44 genes were commonly detected in both tissues. Most findings of the original studies could be confirmed by the meta-analysis with a higher statistical power, but some genes and GO terms related to WNV were newly detected, too. In addition, we identified gene ontology terms related to certain infection processes, which are significantly enriched among the differentially expressed genes. In the neurological tissues, 17 gene ontology terms were found significantly different, and 2 terms in the immunological tissues. Conclusions A critical discussion of our findings shows benefits but also limitations of the meta-analytic approach. In summary, the produced gene lists, identified gene ontology terms and network reconstructions appear to be more reliable than the results from the individual studies. Our meta-analysis provides a basis for further research on the transcriptional mechanisms by WNV infections in neurological tissues. Electronic supplementary material The online version of this article (10.1186/s12864-018-4914-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Robin Kosch
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17p, Hanover, 30559, Germany
| | - Julien Delarocque
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17p, Hanover, 30559, Germany
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Carl-Neuberg-Str. 1, Hanover, 30625, Germany
| | - Stefanie C Becker
- Institute for Parasitology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, Hanover, 30559, Germany.,Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, Hanover, 30559, Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17p, Hanover, 30559, Germany. .,Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, Hanover, 30559, Germany.
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12
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Abstract
Despite being discovered approximately 70 years ago, Zika virus (ZIKV) has received little attention, until the occurrence of alarming epidemics in the Pacific Islands and Latin America between 2013 and 2016. These series of outbreaks resulted in crippling neurological complications in adults, and congenital deformities in new-borns. The dire outcomes marked ZIKV as a re-emerging pathogen of public health concern. Over a period of two years, extensive studies have been conducted to understand different aspects of ZIKV from pathogen biology to infection, including the immune response during virus-host interplay in established animal models, as well as potential therapeutics against ZIKV infection. The vast diversity of novel findings has added value to ZIKV research, and a strategic consolidation is crucial to encompass the latest advances and developments, as well as missing pieces of the puzzle. This review thus aims to provide a concise yet extensive update on current ZIKV studies.
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Affiliation(s)
- Cheryl Yi-Pin Lee
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Lisa F P Ng
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Institute of Infection and Global Health, University of Liverpool, UK.
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13
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Michlmayr D, Andrade P, Gonzalez K, Balmaseda A, Harris E. CD14 +CD16 + monocytes are the main target of Zika virus infection in peripheral blood mononuclear cells in a paediatric study in Nicaragua. Nat Microbiol 2017; 2:1462-1470. [PMID: 28970482 PMCID: PMC5997390 DOI: 10.1038/s41564-017-0035-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 09/01/2017] [Indexed: 01/13/2023]
Abstract
The recent Zika pandemic in the Americas is linked to congenital birth defects and Guillain-Barré syndrome. White blood cells (WBCs) play an important role in host immune responses early in arboviral infection. Infected WBCs can also function as 'Trojan horses' and carry viruses into immune-sheltered spaces, including the placenta, testes and brain. Therefore, defining which WBCs are permissive to Zika virus (ZIKV) is critical. Here, we analyse ZIKV infectivity of peripheral blood mononuclear cells (PBMCs) in vitro and from Nicaraguan Zika patients and show CD14+CD16+ monocytes are the main target of infection, with ZIKV replication detected in some dendritic cells. The frequency of CD14+ monocytes was significantly decreased, while the CD14+CD16+ monocyte population was significantly expanded during ZIKV infection compared to uninfected controls. Viral RNA was detected in PBMCs from all patients, but in serum from only a subset, suggesting PBMCs may be a reservoir for ZIKV. In Zika patients, the frequency of infected cells was lower but the percentage of infected CD14+CD16+ monocytes was significantly higher compared to dengue cases. The gene expression profile in monocytes isolated from ZIKV- and dengue virus-infected patients was comparable, except for significant differences in interferon-γ, CXCL12, XCL1, interleukin-6 and interleukin-10 levels. Thus, our study provides a detailed picture of the innate immune profile of ZIKV infection and highlights the important role of monocytes, and CD14+CD16+ monocytes in particular.
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Affiliation(s)
- Daniela Michlmayr
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, 94720-3370, CA, USA
| | - Paulina Andrade
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, 94720-3370, CA, USA
- Universidad de San Francisco de Quito, Quito, 170157, Ecuador
| | - Karla Gonzalez
- Sustainable Sciences Institute, Managua, 14007, Nicaragua
- Laboratorio Nacional de Virología, Centro Nacional de Diagnóstico y Referencia, Ministry of Health, Managua, 16064, Nicaragua
| | - Angel Balmaseda
- Sustainable Sciences Institute, Managua, 14007, Nicaragua
- Laboratorio Nacional de Virología, Centro Nacional de Diagnóstico y Referencia, Ministry of Health, Managua, 16064, Nicaragua
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, 94720-3370, CA, USA.
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14
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Chemokine Receptor Ccr7 Restricts Fatal West Nile Virus Encephalitis. J Virol 2017; 91:JVI.02409-16. [PMID: 28356527 DOI: 10.1128/jvi.02409-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/07/2017] [Indexed: 12/26/2022] Open
Abstract
West Nile virus (WNV) is a mosquito-transmitted flavivirus that can cause debilitating encephalitis. To delineate the mechanisms behind this pathology, we studied Ccr7-deficient mice, which afforded us the capacity to study infection in mice with disrupted peripheral cellular trafficking events. The loss of Ccr7 resulted in an immediate pan-leukocytosis that remained elevated throughout the infection. This leukocytosis resulted in a significant enhancement of leukocyte accumulation within the central nervous system (CNS). Despite an excess of virus-specific T cells in the CNS, Ccr7-deficient mice had significantly higher CNS viral loads and mortality rates than wild-type animals. Mechanistically, the elevated trafficking of infected myeloid cells into the brain in Ccr7-deficient mice resulted in increased levels of WNV in the CNS, thereby effectively contributing to neuroinflammation and lowering viral clearance. Combined, our experiments suggest that during WNV infection, Ccr7 is a gatekeeper for nonspecific viral transference to the brain.IMPORTANCE In this study, we show that Ccr7 is required for the sufficient migration of dendritic cells and T cells into the draining lymph node immediately following infection and for the restriction of leukocyte migration into the brain. Further, the severe loss of dendritic cells in the draining lymph node had no impact on viral replication in this organ, suggesting that WNV may migrate from the skin into the lymph node through another mechanism. Most importantly, we found that the loss of Ccr7 results in a significant leukocytosis, leading to hypercellularity within the CNS, where monocytes/macrophages contribute to CNS viremia, neuroinflammation, and increased mortality. Together, our data point to Ccr7 as a critical host defense restriction factor limiting neuroinflammation during acute viral infection.
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15
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Uddin MJ, Suen WW, Bosco-Lauth A, Hartwig AE, Hall RA, Bowen RA, Bielefeldt-Ohmann H. Kinetics of the West Nile virus induced transcripts of selected cytokines and Toll-like receptors in equine peripheral blood mononuclear cells. Vet Res 2016; 47:61. [PMID: 27267361 PMCID: PMC4895877 DOI: 10.1186/s13567-016-0347-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 05/17/2016] [Indexed: 12/21/2022] Open
Abstract
West Nile virus (WNV) is one of the most common causes of epidemic viral encephalitis in horses worldwide. Peripheral blood mononuclear cells (PBMCs) are amongst the first to encounter the virus following a mosquito bite. This study aimed to elucidate the transcription kinetics of cytokine, Toll-like receptor (TLRs) and TLRs-associated genes following WNV challenge of equine PBMCs. PBMCs were challenged with an Australian strain of WNV (WNVNSW2011) and transcriptomes were quantified at 2, 6, 12 and 24 h post-infection (pi) using qRT-PCR. Type I and II interferons (IFNα, β and γ) mRNA transcription increased following WNV exposure, as did the transcripts for IL1α, IL1β, IL6, IL8, and IL22, but with slightly varying kinetics. TLR1, 3, 5, 7-9 transcripts were also upregulated in equine PBMCsin response to WNV challenge, as were those for MyD88, NF-κB, TRAF3, STAT1 and 2, IRF3 and 7, ISG15, as well as SOCS1 and 3 compared to the control cells. Expression of selected genes in the draining lymph node, spleen and brain (medulla oblongata) of experimentally infected horses was also assessed and transcription of most of these genes was also upregulated here. Although qRT-PCR detected higher viral RNA at 24 h pi compared to 6 h pi, the virus did not replicate productively in equine PBMCs. The up-regulation of gene-transcription for selected cytokines, IFNs, TLRs and TLRs-associated molecules suggests their involvement in virus recognition and control of WNV infection in the horse.
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Affiliation(s)
- Muhammad Jasim Uddin
- School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia
| | - Willy W Suen
- School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia
| | - Angela Bosco-Lauth
- Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, USA
| | - Airn-Elizabeth Hartwig
- Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, USA
| | - Roy A Hall
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, St Lucia, QLD, Australia
| | - Richard A Bowen
- Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, USA
| | - Helle Bielefeldt-Ohmann
- School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia. .,School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia. .,Australian Infectious Diseases Research Centre, The University of Queensland, St Lucia, QLD, Australia.
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16
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Miner JJ, Diamond MS. Mechanisms of restriction of viral neuroinvasion at the blood-brain barrier. Curr Opin Immunol 2016; 38:18-23. [PMID: 26590675 PMCID: PMC4715944 DOI: 10.1016/j.coi.2015.10.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 10/26/2015] [Indexed: 02/07/2023]
Abstract
The blood-brain barrier (BBB) consists of highly specialized cells including brain microvascular endothelial cells, astrocytes, microglia, pericytes, and neurons, which act in concert to restrict the entry of pathogens, immune cells, and soluble molecules into the central nervous system (CNS). If pathogens manage to cross the BBB and establish infection within the CNS, the BBB can open in a regulated manner to allow leukocyte transmigration into the CNS so that microbes, infected cells, and debris can be cleared. This review highlights how different inflammatory cytokines or signaling pathways disrupt or enhance BBB integrity in a way that regulates entry of neurotropic viruses into the CNS.
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Affiliation(s)
- Jonathan J Miner
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA; Department of Pathology & Immunology, Washington University School of Medicine, St Louis, MO 63110, USA; Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO 63110, USA; Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, MO 63110, USA.
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17
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Uddin MJ, Suen WW, Prow NA, Hall RA, Bielefeldt-Ohmann H. West Nile Virus Challenge Alters the Transcription Profiles of Innate Immune Genes in Rabbit Peripheral Blood Mononuclear Cells. Front Vet Sci 2015; 2:76. [PMID: 26697438 PMCID: PMC4677099 DOI: 10.3389/fvets.2015.00076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/30/2015] [Indexed: 11/13/2022] Open
Abstract
The peripheral innate immune response to West Nile virus (WNV) is crucial for control of virus spread to the central nervous system. Therefore, transcriptomes encoding the innate immune response proteins against WNV were investigated in peripheral blood mononuclear cells (PBMCs) of New Zealand White rabbits, a recently established novel rabbit model for WNV pathogenesis studies. PBMCs were challenged with an Australian WNV strain, WNVNSW2011, in vitro, and mRNA expression of selected immune response genes were quantified at 2-, 6-, 12-, and 24-h post-infection (pi) using qRT-PCR. Compared to mock-inoculated PBMCs, WNV-stimulated PBMCs expressed high levels of interferon (IFN) alpha (IFNA), gamma (IFNG), IL6, IL12, IL22, CXCL10, and pentraxin 3 (PTX3) mRNA. Likewise, TLR1, 2, 3, 4, 6, and 10 mRNA became up-regulated with the highest expression seen for TLR3, 4, and 6. TLRs-signaling downstream genes (MyD88, STAT1, TRAF3, IRF7, and IRF9) subsequently became up-regulated. The high expression of IFNs, TLR3, TLR4, TRAF3, STAT1, IRF7, and IRF9 are in accordance with antiviral activities, while expression of TNFA, HO1, iNOS, caspase 3, and caspase 9 transcripts suggests the involvement of oxidative stress and apoptosis in WNV-stimulated rabbit PBMCs, respectively. The level of WNVNSW2011 RNA increased at 24-h pi in PBMCs challenged with virus in vitro compared to input virus. The expression dynamics of selected genes were validated in PBMCs from rabbits experimentally infected with WNV in vivo. Higher expression of IFNA, IFN beta (IFNB), IFNG, TNFA, IL6, IL22, PTX3, TLR3 and TLR4, IRF7, IRF9, STST1, TRAF3, caspase 3, and caspase 9 were seen in PBMCs from WNV-infected rabbits on day 3 post-intradermal virus inoculation compared to PBMCs from uninfected control rabbits. This study highlights the array of cytokines and TLRs involved in the host innate immune response to WNV in the rabbit leukocytes and suggests that these cells may be a useful in vitro model for WNV infection study.
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Affiliation(s)
- Muhammad J Uddin
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia
| | - Willy W Suen
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia
| | - Natalie A Prow
- QIMR Berghofer Medical Research Institute , Brisbane, QLD , Australia
| | - Roy A Hall
- Australian Infectious Diseases Research Centre, University of Queensland , St Lucia, QLD , Australia ; School of Chemistry and Molecular Biosciences, University of Queensland , St Lucia, QLD , Australia
| | - Helle Bielefeldt-Ohmann
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia ; Australian Infectious Diseases Research Centre, University of Queensland , St Lucia, QLD , Australia ; School of Chemistry and Molecular Biosciences, University of Queensland , St Lucia, QLD , Australia
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18
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Bardina SV, Michlmayr D, Hoffman KW, Obara CJ, Sum J, Charo IF, Lu W, Pletnev AG, Lim JK. Differential Roles of Chemokines CCL2 and CCL7 in Monocytosis and Leukocyte Migration during West Nile Virus Infection. THE JOURNAL OF IMMUNOLOGY 2015; 195:4306-18. [PMID: 26401006 DOI: 10.4049/jimmunol.1500352] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 08/18/2015] [Indexed: 12/24/2022]
Abstract
West Nile virus (WNV) is a re-emerging pathogen and the leading cause of epidemic encephalitis in the United States. Inflammatory monocytes are a critical component of the cellular infiltrate found in the CNS during WNV encephalitis, although the molecular cues involved in their migration are not fully understood. In mice, we previously showed that WNV infection induces a CCR2-dependent monocytosis that precedes monocyte migration into the CNS. Currently, the relative contribution of the CCR2 ligands, chemokines CCL2 and CCL7, in directing monocyte mobilization and leukocyte migration into the CNS is unclear. In this study, we demonstrate that, although both CCL2 and CCL7 are required for efficient monocytosis and monocyte accumulation in the CNS, only CCL7 deficiency resulted in increased viral burden in the brain and enhanced mortality. The enhanced susceptibility in the absence of CCL7 was associated with the delayed migration of neutrophils and CD8(+) T cells into the CNS compared with WT or Ccl2(-/-) mice. To determine whether CCL7 reconstitution could therapeutically alter the survival outcome of WNV infection, we administered exogenous CCL7 i.v. to WNV-infected Ccl7(-/-) mice and observed a significant increase in monocytes and neutrophils, but not CD8(+) T cells, within the CNS, as well as an enhancement in survival compared with Ccl7(-/-) mice treated with a linear CCL7 control peptide. Our experiments suggest that CCL7 is an important protective signal involved in leukocyte trafficking during WNV infection, and it may have therapeutic potential for the treatment of acute viral infections of the CNS.
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Affiliation(s)
- Susana V Bardina
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Daniela Michlmayr
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Kevin W Hoffman
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Christopher J Obara
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Janet Sum
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Israel F Charo
- Cardiovascular Research Institute, Department of Medicine, University of California San Francisco, San Francisco, CA 94549
| | - Wuyuan Lu
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201; Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201; and
| | - Alexander G Pletnev
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Jean K Lim
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029;
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19
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Dietrich EA, Bowen RA, Brault AC. An ex vivo avian leukocyte culture model for West Nile virus infection. J Virol Methods 2015; 218:19-22. [PMID: 25783683 PMCID: PMC4583197 DOI: 10.1016/j.jviromet.2015.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 02/20/2015] [Accepted: 03/06/2015] [Indexed: 12/22/2022]
Abstract
West Nile virus (WNV) replicates in a wide variety of avian species, which act as amplification hosts. In particular, WNV generates high titers and elicits severe pathology in American crows (AMCRs; Corvus brachyrhynchos), a species that has been used as a sentinel for WNV transmission. Although the specific cellular targets of WNV replication in AMCRs are not well defined, preliminary evidence suggests that leukocytes may be an important target of early replication. Therefore, development of a protocol for ex vivo culture of AMCR leukocytes as a model for assessing differential avian host susceptibility is described herein. WNV growth in these cultures mirrored in vivo viremia profiles. These data indicate that ex vivo leukocyte cultures can be used for preliminary pathological assessment of novel WNV strains and potentially of other flaviviruses that use avian reservoir hosts.
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Affiliation(s)
- Elizabeth A Dietrich
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521, United States
| | - Richard A Bowen
- Department of Biomedical Sciences, Colorado State University, 1683 Campus Delivery, Fort Collins, CO 80523-1683, United States
| | - Aaron C Brault
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521, United States.
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20
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Demeestere D, Libert C, Vandenbroucke RE. Clinical implications of leukocyte infiltration at the choroid plexus in (neuro)inflammatory disorders. Drug Discov Today 2015; 20:928-41. [PMID: 25979470 DOI: 10.1016/j.drudis.2015.05.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 04/30/2015] [Accepted: 05/05/2015] [Indexed: 12/29/2022]
Abstract
The choroid plexus (CP) is a highly vascularized organ located in the brain ventricles and contains a single epithelial cell layer forming the blood-cerebrospinal fluid barrier (BCSFB). This barrier is crucial for immune surveillance in health and is an underestimated gate for entry of immune cells during numerous inflammatory disorders. Several of these disorders are accompanied by disturbance of the BCSFB and increased leukocyte infiltration, which affects neuroinflammation. Understanding the mechanism of immune cell entry at the CP might lead to identification of new therapeutic targets. Here, we focus on current knowledge of leukocyte infiltration at the CP in inflammatory conditions and its therapeutic implications.
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Affiliation(s)
- Delphine Demeestere
- Inflammation Research Center, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Claude Libert
- Inflammation Research Center, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Roosmarijn E Vandenbroucke
- Inflammation Research Center, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
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21
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Suen WW, Prow NA, Hall RA, Bielefeldt-Ohmann H. Mechanism of West Nile virus neuroinvasion: a critical appraisal. Viruses 2014; 6:2796-825. [PMID: 25046180 PMCID: PMC4113794 DOI: 10.3390/v6072796] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/09/2014] [Accepted: 07/10/2014] [Indexed: 12/11/2022] Open
Abstract
West Nile virus (WNV) is an important emerging neurotropic virus, responsible for increasingly severe encephalitis outbreaks in humans and horses worldwide. However, the mechanism by which the virus gains entry to the brain (neuroinvasion) remains poorly understood. Hypotheses of hematogenous and transneural entry have been proposed for WNV neuroinvasion, which revolve mainly around the concepts of blood-brain barrier (BBB) disruption and retrograde axonal transport, respectively. However, an over‑representation of in vitro studies without adequate in vivo validation continues to obscure our understanding of the mechanism(s). Furthermore, WNV infection in the current rodent models does not generate a similar viremia and character of CNS infection, as seen in the common target hosts, humans and horses. These differences ultimately question the applicability of rodent models for pathogenesis investigations. Finally, the role of several barriers against CNS insults, such as the blood-cerebrospinal fluid (CSF), the CSF-brain and the blood-spinal cord barriers, remain largely unexplored, highlighting the infancy of this field. In this review, a systematic and critical appraisal of the current evidence relevant to the possible mechanism(s) of WNV neuroinvasion is conducted.
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Affiliation(s)
- Willy W Suen
- School of Veterinary Science, University of Queensland, Gatton, QLD, 4343, Australia.
| | - Natalie A Prow
- Australian Infectious Diseases Research Centre, University of Queensland, St. Lucia, QLD, 4072, Australia.
| | - Roy A Hall
- Australian Infectious Diseases Research Centre, University of Queensland, St. Lucia, QLD, 4072, Australia.
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22
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Detournay O, Morrison DA, Wagner B, Zarnegar B, Wattrang E. Genomic analysis and mRNA expression of equine type I interferon genes. J Interferon Cytokine Res 2013; 33:746-59. [PMID: 23772953 DOI: 10.1089/jir.2012.0130] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
This study aimed at identifying all of the type I interferon (IFN) genes of the horse and at monitoring their expression in equine cells on in vitro induction. We identified 32 putative type I IFN loci on horse chromosome 23 and an unplaced genomic scaffold. A phylogentic analysis characterized these into 8 different type I IFN classes, that is, putative functional genes for 6 IFN-α, 4 IFN-β, 8 IFN-ω (plus 4 pseudogenes), 3 IFN-δ (plus 1 pseudogene), 1 IFN-κ and 1 IFN-ε, plus 1 IFN-ν pseudogene, and 3 loci belonging to what has previously been called IFN-αω. Our analyses indicate that the IFN-αω genes are quite distinct from both IFN-α and IFN-ω, and we refer to this type I IFN as IFN-μ. Results from cell cultures showed that leukocytes readily expressed IFN-α, IFN-β, IFN-δ, IFN-μ, and IFN-ω mRNA on induction with, for example, live virus; while fibroblasts only expressed IFN-β mRNA on stimulation. IFN-κ or IFN-ε expression was not consistently induced in these cell cultures. Thus, the equine type I IFN family comprised 8 classes, 7 of which had putative functional genes, and mRNA expression of 5 was induced in vitro. Moreover, a relatively low number of IFN-α subtypes was found in the horse compared with other eutherian mammals.
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Affiliation(s)
- Olivier Detournay
- 1 Department of Virology, Immunobiology and Parasitology, National Veterinary Institute , Uppsala, Sweden
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23
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Gamino V, Höfle U. Pathology and tissue tropism of natural West Nile virus infection in birds: a review. Vet Res 2013; 44:39. [PMID: 23731695 PMCID: PMC3686667 DOI: 10.1186/1297-9716-44-39] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Accepted: 04/24/2013] [Indexed: 01/26/2023] Open
Abstract
West Nile virus (WNV) is a globally distributed arthropod-borne flavivirus capable of infecting a wide variety of vertebrates, with birds as its natural reservoir. Although it had been considered a pathogen of little importance for birds, from the 1990's, and especially after its introduction in the North American continent in 1999, thousands of birds have succumbed to West Nile infection. This review summarizes the pathogenesis and pathology of WNV infection in birds highlighting differences in lesion and antigen distribution and severity among bird orders and families. Despite significant species differences in susceptibility to infection, WNV associated lesions and viral antigen are present in the majority of organs of infected birds. The non-progressive, acute or more prolonged course of the disease accounts for part of the differences in lesion and viral antigen distribution and lesion severity. Most likely a combination of host variables and environmental factors in addition to the intrinsic virulence and pathogenicity of the infecting WNV strain influence the pathogenesis of the infection.
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Affiliation(s)
- Virginia Gamino
- SaBio Instituto de Investigación en Recursos Cinegéticos IREC, (CSIC-UCLM-JCCM) Ronda de Toledo s/n, Ciudad Real 13005, Spain
| | - Ursula Höfle
- SaBio Instituto de Investigación en Recursos Cinegéticos IREC, (CSIC-UCLM-JCCM) Ronda de Toledo s/n, Ciudad Real 13005, Spain
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24
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Immune responses to West Nile virus infection in the central nervous system. Viruses 2012; 4:3812-30. [PMID: 23247502 PMCID: PMC3528292 DOI: 10.3390/v4123812] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 12/07/2012] [Accepted: 12/10/2012] [Indexed: 12/16/2022] Open
Abstract
West Nile virus (WNV) continues to cause outbreaks of severe neuroinvasive disease in humans and other vertebrate animals in the United States, Europe, and other regions of the world. This review discusses our understanding of the interactions between virus and host that occur in the central nervous system (CNS), the outcome of which can be protection, viral pathogenesis, or immunopathogenesis. We will focus on defining the current state of knowledge of WNV entry, tropism, and host immune response in the CNS, all of which affect the balance between injury and successful clearance.
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25
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De Filette M, Ulbert S, Diamond M, Sanders NN. Recent progress in West Nile virus diagnosis and vaccination. Vet Res 2012; 43:16. [PMID: 22380523 PMCID: PMC3311072 DOI: 10.1186/1297-9716-43-16] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 03/01/2012] [Indexed: 01/22/2023] Open
Abstract
West Nile virus (WNV) is a positive-stranded RNA virus belonging to the Flaviviridae family, a large family with 3 main genera (flavivirus, hepacivirus and pestivirus). Among these viruses, there are several globally relevant human pathogens including the mosquito-borne dengue virus (DENV), yellow fever virus (YFV), Japanese encephalitis virus (JEV) and West Nile virus (WNV), as well as tick-borne viruses such as tick-borne encephalitis virus (TBEV). Since the mid-1990s, outbreaks of WN fever and encephalitis have occurred throughout the world and WNV is now endemic in Africa, Asia, Australia, the Middle East, Europe and the Unites States. This review describes the molecular virology, epidemiology, pathogenesis, and highlights recent progress regarding diagnosis and vaccination against WNV infections.
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Affiliation(s)
- Marina De Filette
- Laboratory of Gene Therapy, Faculty of Veterinary Sciences, Ghent University, Heidestraat 19, 9820 Merelbeke, Belgium.
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26
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Arjona A, Wang P, Montgomery RR, Fikrig E. Innate immune control of West Nile virus infection. Cell Microbiol 2011; 13:1648-58. [PMID: 21790942 DOI: 10.1111/j.1462-5822.2011.01649.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
West Nile virus (WNV), from the Flaviviridae family, is a re-emerging zoonotic pathogen of medical importance. In humans, WNV infection may cause life-threatening meningoencephalitis or long-term neurologic sequelae. WNV is transmitted by Culex spp. mosquitoes and both the arthropod vector and the mammalian host are equipped with antiviral innate immune mechanisms sharing a common phylogeny. As far as the current evidence is able to demonstrate, mosquitoes primarily rely on RNA interference, Toll, Imd and JAK-STAT signalling pathways for limiting viral infection, while mammals are provided with these and other more complex antiviral mechanisms involving antiviral effectors, inflammatory mediators, and cellular responses triggered by highly specialized pathogen detection mechanisms that often resemble their invertebrate ancestry. This mini-review summarizes our current understanding of how the innate immune systems of the vector and the mammalian host react to WNV infection and shape its pathogenesis.
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Affiliation(s)
- Alvaro Arjona
- Section of Infectious Diseases, Yale School of Medicine, New Haven, CT, USA
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27
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Lim SM, Koraka P, Osterhaus AD, Martina BE. West Nile virus: immunity and pathogenesis. Viruses 2011; 3:811-28. [PMID: 21994755 PMCID: PMC3185772 DOI: 10.3390/v3060811] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Revised: 05/26/2011] [Accepted: 05/27/2011] [Indexed: 11/17/2022] Open
Abstract
West Nile virus (WNV) is a neurotropic, arthropod-borne flavivirus that is maintained in an enzootic cycle between mosquitoes and birds, but can also infect and cause disease in horses and humans. WNV is endemic in parts of Africa, Europe, the Middle East, and Asia, and since 1999 has spread to North America, Mexico, South America, and the Caribbean. WNV infects the central nervous system (CNS) and can cause severe disease in a small minority of infected humans, mostly immunocompromised or the elderly. This review discusses some of the mechanisms by which the immune system can limit dissemination of WNV infection and elaborates on the mechanisms involved in pathogenesis. Reasons for susceptibility to WNV-associated neuroinvasive disease in less than 1% of cases remain unexplained, but one favored hypothesis is that the involvement of the CNS is associated with a weak immune response allowing robust WNV replication in the periphery and spread of the virus to the CNS.
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Affiliation(s)
- Stephanie M. Lim
- Department of Virology, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands; E-Mails: (S.M.L.); (P.K.); (A.D.M.E.O.)
| | - Penelope Koraka
- Department of Virology, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands; E-Mails: (S.M.L.); (P.K.); (A.D.M.E.O.)
| | - Albert D.M.E. Osterhaus
- Department of Virology, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands; E-Mails: (S.M.L.); (P.K.); (A.D.M.E.O.)
| | - Byron E.E. Martina
- Department of Virology, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands; E-Mails: (S.M.L.); (P.K.); (A.D.M.E.O.)
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28
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Neutralization escape variant of West Nile virus associated with altered peripheral pathogenicity and differential cytokine profile. Virus Res 2011; 158:130-9. [DOI: 10.1016/j.virusres.2011.03.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/28/2011] [Accepted: 03/28/2011] [Indexed: 11/19/2022]
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29
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Kimura T, Sasaki M, Okumura M, Kim E, Sawa H. Flavivirus encephalitis: pathological aspects of mouse and other animal models. Vet Pathol 2010; 47:806-18. [PMID: 20551474 DOI: 10.1177/0300985810372507] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Encephalitic flaviviruses are important arthropod-borne pathogens of humans and other animals. In particular, the recent emergence of the West Nile virus (WNV) and Japanese encephalitis virus (JEV) in new geographic areas has caused a considerable public health alert and international concern. Among the experimental in vivo models of WNV and JEV infection, mice and other laboratory rodents are the most thoroughly studied and well-characterized systems, having provided data that are important for understanding the infectious process in humans. Macaca monkeys have also been used as a model for WNV and JEV infection, mainly for the evaluation of vaccine efficacy, although a limited number of published studies have addressed pathomorphology. These animal models demonstrate the development of encephalitis with many similarities to the human disease; however, the histological events that occur during infection, especially in peripheral tissues, have not been fully characterized.
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Affiliation(s)
- T Kimura
- Department of Molecular Pathobiology, Hokkaido University Research Center for Zoonosis Control, West 10 North 20, Kita-ku, Sapporo 001-0020 Japan.
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30
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Xiang J, McLinden JH, Rydze RA, Chang Q, Kaufman TM, Klinzman D, Stapleton JT. Viruses within the Flaviviridae decrease CD4 expression and inhibit HIV replication in human CD4+ cells. THE JOURNAL OF IMMUNOLOGY 2010; 183:7860-9. [PMID: 19923460 DOI: 10.4049/jimmunol.0902276] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Viral infections alter host cell homeostasis and this may lead to immune evasion and/or interfere with the replication of other microbes in coinfected hosts. Two flaviviruses are associated with a reduction in HIV replication or improved survival in HIV-infected people (dengue virus (DV) and GB virus type C (GBV-C)). GBV-C infection and expression of the GBV-C nonstructural protein 5A (NS5A) and the DV NS5 protein in CD4(+) T cells inhibit HIV replication in vitro. To determine whether the inhibitory effect on HIV replication is conserved among other flaviviruses and to characterize mechanism(s) of HIV inhibition, the NS5 proteins of GBV-C, DV, hepatitis C virus, West Nile virus, and yellow fever virus (YFV; vaccine strain 17D) were expressed in CD4(+) T cells. All NS5 proteins inhibited HIV replication. This correlated with decreased steady-state CD4 mRNA levels and reduced cell surface CD4 protein expression. Infection of CD4(+) T cells and macrophages with YFV (17D vaccine strain) also inhibited HIV replication and decreased CD4 gene expression. In contrast, mumps virus was not inhibited by the expression of flavivirus NS5 protein or by YFV infection, and mumps infection did not alter CD4 mRNA or protein levels. In summary, CD4 gene expression is decreased by all human flavivirus NS5 proteins studied. CD4 regulation by flaviviruses may interfere with innate and adaptive immunity and contribute to in vitro HIV replication inhibition. Characterization of the mechanisms by which flaviviruses regulate CD4 expression may lead to novel therapeutic strategies for HIV and immunological diseases.
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Affiliation(s)
- Jinhua Xiang
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center and University of Iowa, Iowa City, IA 52242, USA
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31
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Effector functions of camelid heavy-chain antibodies in immunity to West Nile virus. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 17:239-46. [PMID: 19955323 DOI: 10.1128/cvi.00421-09] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Three classes of IgG have been described for camelids. IgG1 has a conventional four-chain structure, while IgG2 and IgG3 do not incorporate light chains. The structures and antigen-binding affinities of the so-called heavy-chain classes have been studied in detail; however, their regulation and effector functions are largely undefined. The aim of this study was to examine the participation of conventional and heavy-chain IgG antibodies in the camelid immune defense directed against West Nile virus (WNV). We found that natural infection or vaccination with killed WNV induced IgG1 and IgG3. Vaccination also induced IgG1 and IgG3; IgG2 was produced during the anamnestic response to vaccination. When purified IgGs were tested in plaque-reduction neutralization titer (PRNT) tests, IgG3 demonstrated PRNT activities comparable to those of conventional IgG1. In contrast, IgG2 demonstrated only suboptimal activity at the highest concentrations tested. Flow cytometric analysis revealed that macrophages bound IgG1, IgG2, and IgG3. Furthermore, subneutralizing concentrations of all three isotypes enhanced WNV infection of cultured macrophages. Our results document distinctions in regulation and function between camelid heavy-chain isotypes. The reduced size and distinct structure of IgG3 did not negatively impact its capacity to neutralize virus. In contrast, IgG2 appeared to be less efficient in neutralization. This information advances our understanding of these unusual antibodies in ways that can be applied in the development of effective vaccines for camelids.
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32
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Garcia-Tapia D, Hassett DE, Mitchell WJ, Johnson GC, Kleiboeker SB. West Nile virus encephalitis: sequential histopathological and immunological events in a murine model of infection. J Neurovirol 2007; 13:130-8. [PMID: 17505981 DOI: 10.1080/13550280601187185] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
West Nile virus (WNV) has emerged as an important cause of encephalitis in humans and horses in North America. Although there is significant knowledge about the pathogenesis of disease caused by this flavivirus and about the immunity against it, no reports exist describing the sequence of pathological changes and their correlation to the immune response in the brain following infection with WNV. In this report the authors describe the major histopathological changes, as well as changes in cytokine and chemokine expression, in brains from WNV-infected C57Bl/6 mice. During the course of infection skin, spleen and kidney were all sites of WNV replication before virus reached the brain. In brain, increased expression of the chemokines monocyte chemoattractant protein (MCP)-5 (CCL12), interferon gamma inducible protein 10 (IP-10; CXCL10), and monokine induced by gamma interferon (MIG; CXCL9) preceded the expression of interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha), which have previously been considered to be key early cytokines in the pathogenesis and immune response of WNV encephalitis. These results suggest that the chemokines MCP-5, IP-10, and MIG are important triggers of inflammation in brain due to their early up-regulation following WNV infection.
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Affiliation(s)
- David Garcia-Tapia
- Department of Veterinary Pathobiology Department, University of Missouri-Columbia, Columbia, Missouri 65211, USA.
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33
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Samuel MA, Diamond MS. Pathogenesis of West Nile Virus infection: a balance between virulence, innate and adaptive immunity, and viral evasion. J Virol 2006; 80:9349-60. [PMID: 16973541 PMCID: PMC1617273 DOI: 10.1128/jvi.01122-06] [Citation(s) in RCA: 235] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Melanie A Samuel
- Division of Infectious Diseases, Department of Molecular Microbiology, Washington University School of Medicine, Campus Box 8051, 660 S. Euclid Ave., St. Louis, MO 63110, USA
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34
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Shrestha B, Wang T, Samuel MA, Whitby K, Craft J, Fikrig E, Diamond MS. Gamma interferon plays a crucial early antiviral role in protection against West Nile virus infection. J Virol 2006; 80:5338-48. [PMID: 16699014 PMCID: PMC1472130 DOI: 10.1128/jvi.00274-06] [Citation(s) in RCA: 157] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 03/08/2006] [Indexed: 12/17/2022] Open
Abstract
West Nile virus (WNV) causes a severe central nervous system (CNS) infection in humans, primarily in the elderly and immunocompromised. Prior studies have established an essential protective role of several innate immune response elements, including alpha/beta interferon (IFN-alpha/beta), immunoglobulin M, gammadelta T cells, and complement against WNV infection. In this study, we demonstrate that a lack of IFN-gamma production or signaling results in increased vulnerability to lethal WNV infection by a subcutaneous route in mice, with a rise in mortality from 30% (wild-type mice) to 90% (IFN-gamma(-/-) or IFN-gammaR(-/-) mice) and a decrease in the average survival time. This survival pattern in IFN-gamma(-/-) and IFN-gammaR(-/-) mice correlated with higher viremia and greater viral replication in lymphoid tissues. The increase in peripheral infection led to early CNS seeding since infectious WNV was detected several days earlier in the brains and spinal cords of IFN-gamma(-/-) or IFN-gammaR(-/-) mice. Bone marrow reconstitution experiments showed that gammadelta T cells require IFN-gamma to limit dissemination by WNV. Moreover, treatment of primary dendritic cells with IFN-gamma reduced WNV production by 130-fold. Collectively, our experiments suggest that the dominant protective role of IFN-gamma against WNV is antiviral in nature, occurs in peripheral lymphoid tissues, and prevents viral dissemination to the CNS.
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Affiliation(s)
- Bimmi Shrestha
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave., Box 8051, St. Louis, MO 63110, USA
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