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Moalem Y, Katz R, Subramaniam AG, Malis Y, Yaffe Y, Borenstein-Auerbach N, Tadmor K, Raved R, Maoz BM, Yoo JS, Lustig Y, Luxenburg C, Perlson E, Einav S, Sklan EH. Numb-associated kinases regulate sandfly-borne Toscana virus entry. Emerg Microbes Infect 2024:2382237. [PMID: 39017647 DOI: 10.1080/22221751.2024.2382237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
Sandfly-borne Toscana virus (TOSV) is an enveloped tri-segmented negative single-strand RNA Phlebovirus. It is an emerging virus predominantly endemic in southwestern Europe and Northern Africa. Although TOSV infection is typically asymptomatic or results in mild febrile disease, it is neurovirulent and ranks among the three most common causes of summer meningitis in certain regions. Despite this clinical significance, our understanding of the molecular aspects and host factors regulating phlebovirus infection is limited.This study characterized the early steps of TOSV infection. Our findings reveal that two members of the Numb-associated kinases family of Ser/Thr kinases, namely adaptor-associated kinase 1 (AAK1) and cyclin G-associated kinase (GAK), play a role in regulating the early stages of TOSV entry. FDA-approved inhibitors targeting these kinases demonstrated significant inhibition of TOSV infection. This study suggests that AAK1 and GAK represent druggable targets for inhibiting TOSV infection and, potentially, related Phleboviruses.
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Affiliation(s)
- Yarden Moalem
- Department of Clinical Microbiology and Immunology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Rodolfo Katz
- Department of Clinical Microbiology and Immunology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Anand G Subramaniam
- Department of Physiology and Pharmacology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Yehonathan Malis
- Department of Pathology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Yakey Yaffe
- The Drimmer-Fischler Family Stem Cell Core Laboratory for Regenerative Medicine, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Nofit Borenstein-Auerbach
- Department of Cell and Developmental Biology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Keshet Tadmor
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Roey Raved
- School of Neurobiology, Biochemistry and Biophysics, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ben M Maoz
- The Drimmer-Fischler Family Stem Cell Core Laboratory for Regenerative Medicine, Tel Aviv University, Tel Aviv, 6997801, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ji Seung Yoo
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Yaniv Lustig
- Central Virology Laboratory, Ministry of Health, Chaim Sheba Medical Center, Tel Hashomer, 52621, Israel
- School of Public Health, School of Medicine, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Chen Luxenburg
- Department of Cell and Developmental Biology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Eran Perlson
- Department of Physiology and Pharmacology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Shirit Einav
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, United States of America
- Department of Microbiology and Immunology, Stanford University, Stanford, California, United States of America
- Chan Zuckerberg Biohub, San Francisco, California, United States of America
| | - Ella H Sklan
- Department of Clinical Microbiology and Immunology, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
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Hacioglu S, Ozkul A. Do birds play a role in the transmission of Toscana virus? Initial isolation results from birds in northernmost Türkiye. Zoonoses Public Health 2024; 71:225-235. [PMID: 38041213 DOI: 10.1111/zph.13100] [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: 03/25/2023] [Revised: 11/22/2023] [Accepted: 11/23/2023] [Indexed: 12/03/2023]
Abstract
AIMS Recent research has prioritized emerging and re-emerging diseases that affect human and animal health, particularly to describe how these diseases enter countries and determine their transmission cycles. Given that migratory birds play a significant role in spreading infections, the present study analysed their migration paths and specimens to investigate Orthoflavivirus, Orthonairovirus, Alphavirus and Phlebovirus in birds in Samsun province, Türkiye. METHODS AND RESULTS For these viruses, 312 samples from 56 birds were analysed using RT-PCR and qRT-PCR. Toscana virus (TOSV) was identified in 14 birds (four mallards, five partridges, four quails and one pigeon), representing 25% of the birds sampled. Genotype B was reported in all 14 birds. After inoculating the positive tissues in cell cultures, TOSV was isolated from the organs of pigeons, mallards and partridges. CONCLUSIONS This is the first time TOSV has been isolated in cell culture from birds and indicates that they may play a role in spreading TOSV in Türkiye. The results also suggest that TOSV might be carried between countries by migratory birds.
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Affiliation(s)
- Sabri Hacioglu
- Virological Diagnostic Laboratory, Veterinary Control Central Research Institute, Ankara, Turkey
| | - Aykut Ozkul
- Department of Virology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
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3
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Hartman AL, Myler PJ. Bunyavirales: Scientific Gaps and Prototype Pathogens for a Large and Diverse Group of Zoonotic Viruses. J Infect Dis 2023; 228:S376-S389. [PMID: 37849397 PMCID: PMC10582323 DOI: 10.1093/infdis/jiac338] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023] Open
Abstract
Research directed at select prototype pathogens is part of the approach put forth by the National Institute of Allergy and Infectious Disease (NIAID) to prepare for future pandemics caused by emerging viruses. We were tasked with identifying suitable prototypes for four virus families of the Bunyavirales order (Phenuiviridae, Peribunyaviridae, Nairoviridae, and Hantaviridae). This is a challenge due to the breadth and diversity of these viral groups. While there are many differences among the Bunyavirales, they generally have complex ecological life cycles, segmented genomes, and cause a range of human clinical outcomes from mild to severe and even death. Here, we delineate potential prototype species that encompass the breadth of clinical outcomes of a given family, have existing reverse genetics tools or animal disease models, and can be amenable to a platform approach to vaccine testing. Suggested prototype pathogens outlined here can serve as a starting point for further discussions.
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Affiliation(s)
- Amy L Hartman
- Center for Vaccine Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Infectious Diseases and Microbiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, USA
| | - Peter J Myler
- Department of Pediatrics and the Department of Biomedical Informatics and Medical Education, University of Washington, Seattle, Washington, USA
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
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4
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Benbetka C, Hachid A, Benallal KE, Khardine FA, Ayhan N, Bouredjoul N, Boulehbal WM, Bellila D, Khaldi A, Charrel R. Epidemiology, Isolation, and Genetic Characterization of Toscana Virus in Algerian Patients Displaying Neurological Infection, 2016-2018. IJID REGIONS 2023; 7:193-198. [PMID: 37123383 PMCID: PMC10131063 DOI: 10.1016/j.ijregi.2023.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 05/02/2023]
Abstract
Purpose The current study reports the results of the diagnosis of neuro-invasive Toscana virus (TOSV) infection in Algeria between 2016 and 2018 and describes the first isolation of TOSV strain from human samples in North Africa. Materiel and methods Cerebrospinal fluid (CSF) and sera samples were obtained from 720 hospitalized patients displaying neurological infection symptoms of unknown etiology, of which 604 were screened for TOSV. The diagnosis was performed by serological and/or RT-PCR tests. In addition, TOSV was isolated in vivo and in vitro from CSF and genetically characterized. Results 23 cases of TOSV neurological infections were detected. Cases were located in 11 Wilayas (administrative provinces), mainly in northern Algeria. In addition, we report the isolation of TOSV strain belonging to lineage A from human samples with its complete coding sequence. Conclusion Even though the number of infections is probably underestimated, TOSV is endemic in Algeria, with several cases of neuro-invasive diseases in humans recorded each year. Therefore, the diagnosis of TOSV should be included in the differential diagnosis of neurological diseases, especially aseptic meningitis, during the period of activity of the phlebotomine vector. Further studies are required to measure precisely the nationwide prevalence of TOSV in Algeria.
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Affiliation(s)
- Chahrazed Benbetka
- Laboratory of Arboviruses and Emerging Viruses, Institut Pasteur of Algeria, 16000, Algiers, Algeria
- Department of Immunology, Béni-Messous Teaching Hospital, University of Algiers, 16000, Algiers, Algeria
- Faculty of Pharmacy, University of Algiers 1, 16000, Algiers, Algeria
- Co-first authors.
| | - Aissam Hachid
- Laboratory of Arboviruses and Emerging Viruses, Institut Pasteur of Algeria, 16000, Algiers, Algeria
- Faculty of Pharmacy, University of Algiers 1, 16000, Algiers, Algeria
- Co-first authors.
| | - Kamal Eddine Benallal
- Laboratory of Parasitic Eco-epidemiology and Population Genetics, Institut Pasteur of Algeria, 16000, Algiers, Algeria
| | - Fayez Ahmed Khardine
- Laboratory of Arboviruses and Emerging Viruses, Institut Pasteur of Algeria, 16000, Algiers, Algeria
| | - Nazli Ayhan
- Unité des Virus Emergents, UVE: Aix Marseille Université, IRD 190, Inserm 1207, AP-HM Hôpitaux Universitaires de Marseille, 13005, Marseille, France
| | - Nesrine Bouredjoul
- Laboratory of Arboviruses and Emerging Viruses, Institut Pasteur of Algeria, 16000, Algiers, Algeria
| | | | - Djamila Bellila
- Faculty of Natural Sciences, University of Algiers 1, 16000, Algiers, Algeria
| | - Aldjia Khaldi
- Laboratory of Arboviruses and Emerging Viruses, Institut Pasteur of Algeria, 16000, Algiers, Algeria
- Faculty of Pharmacy, University of Algiers 1, 16000, Algiers, Algeria
| | - Rémi Charrel
- Unité des Virus Emergents, UVE: Aix Marseille Université, IRD 190, Inserm 1207, AP-HM Hôpitaux Universitaires de Marseille, 13005, Marseille, France
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Ayhan N, Alten B, Ivovic V, Cvetkovikj A, Stefanovska J, Martinkovic F, Piorkowski G, Moureau G, Gould EA, Pettersson JHO, de Lamballerie X, Charrel RN. Field surveys in Croatia and North Macedonia reveal two novel phleboviruses circulating in sandflies. J Gen Virol 2021; 102. [PMID: 34797756 DOI: 10.1099/jgv.0.001674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sandfly-borne phleboviruses are distributed widely throughout the Mediterranean Basin, presenting a threat to public health in areas where they circulate. However, the true diversity and distribution of pathogenic and apathogenic sandfly-borne phleboviruses remains a key issue to be studied. In the Balkans, most published data rely on serology-based studies although virus isolation has occasionally been reported. Here, we report the discovery of two novel sandfly-borne phleboviruses, provisionally named Zaba virus (ZABAV) and Bregalaka virus (BREV), which were isolated in Croatia and North Macedonia, respectively. This constitutes the first isolation of phleboviruses in both countries. Genetic analysis based on complete coding sequences indicated that ZABAV and BREV are distinct from each other and belong to the genus Phlebovirus, family Phenuiviridae. Phylogenetic and amino acid modelling of viral polymerase shows that ZABAV and BREV are new members of the Salehabad phlebovirus species and the Adana phlebovirus species, respectively. Moreover, sequence-based vector identification suggests that ZABAV is mainly transmitted by Phlebotomus neglectus and BREV is mainly transmitted by Phlebotomus perfiliewi. BREV neutralizing antibodies were detected in 3.3% of human sera with rates up to 16.7% in certain districts, demonstrating that BREV frequently infects humans in North Macedonia. In vitro viral growth kinetics experiments demonstrated viral replication of both viruses in mammalian and mosquito cells. In vivo experimental studies in mice suggest that ZABAV and BREV exhibit characteristics making them possible human pathogens.
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Affiliation(s)
- Nazli Ayhan
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
| | - Bulent Alten
- Faculty of Science, Department of Biology, Ecology Division, VERG Labs, Hacettepe University, Beytepe, Ankara, Turkey
| | - Vladimir Ivovic
- Faculty of Mathematics, Natural Sciences and Information Technologies (FAMNIT), University of Primorska, Koper, Slovenia
| | - Aleksandar Cvetkovikj
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Ss. Cyril and Methodius University in Skopje, Lazar Pop-Trajkov 5-7, 1000 Skopje, Republic of North Macedonia
| | - Jovana Stefanovska
- Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Ss. Cyril and Methodius University in Skopje, Lazar Pop-Trajkov 5-7, 1000 Skopje, Republic of North Macedonia
| | - Franjo Martinkovic
- Faculty of Veterinary Medicine, Department of Parasitology and Parasitic Diseases with Clinics, University of Zagreb, Zagreb, Croatia
| | - Geraldine Piorkowski
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
| | - Gregory Moureau
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
| | - Ernest A Gould
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
| | - John H-O Pettersson
- Department of Medical Biochemistry and Microbiology (IMBIM), Zoonosis Science Center, Uppsala University, Uppsala, Sweden.,Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences and Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Xavier de Lamballerie
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
| | - Remi N Charrel
- Unite des Virus Emergents (Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Mediterranee Infection), Marseille, France
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Gori Savellini G, Bini L, Gagliardi A, Anichini G, Gandolfo C, Prathyumnan S, Cusi MG. Ubiquitin and Not Only Unfolded Domains Drives Toscana Virus Non-Structural NSs Protein Degradation. Viruses 2020; 12:E1153. [PMID: 33053780 PMCID: PMC7601456 DOI: 10.3390/v12101153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 01/09/2023] Open
Abstract
The non-structural protein NSs of the Phenuiviridae family members appears to have a role in the host immunity escape. The stability of Toscana virus (TOSV) NSs protein was tested by a cycloheximide (CHX) chase approach on cells transfected with NSs deleted versions fused to a reporter gene. The presence of intrinsically disordered regions (IDRs) both at the C- and N-terminus appeared to affect the protein stability. Indeed, the NSsΔC and NSsΔN proteins were more stable than the wild-type NSs counterpart. Since TOSV NSs exerts its inhibitory function by triggering RIG-I for proteasomal degradation, the interaction of the ubiquitin system and TOSV NSs was further examined. Chase experiments with CHX and the proteasome inhibitor MG-132 demonstrated the involvement of the ubiquitin-proteasome system in controlling NSs protein amount expressed in the cells. The analysis of TOSV NSs by mass spectrometry allowed the direct identification of K104, K109, K154, K180, K244, K294, and K298 residues targeted for ubiquitination. Analysis of NSs K-mutants confirmed the presence and the important role of lysine residues located in the central and the C-terminal parts of the protein in controlling the NSs cellular level. Therefore, we directly demonstrated a new cellular pathway involved in controlling TOSV NSs fate and activity, and this opens the way to new investigations among more pathogenic viruses of the Phenuiviridae family.
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Affiliation(s)
- Gianni Gori Savellini
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Luca Bini
- Department of Life Sciences, University of Siena, 53100 Siena, Italy;
| | - Assunta Gagliardi
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Laboratory of Synthetic and Structural Vaccinology, 38122 Trento, Italy;
| | - Gabriele Anichini
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Claudia Gandolfo
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
- S. Maria delle Scotte Hospital, V.le Bracci, 1, 53100 Siena, Italy
| | - Shibily Prathyumnan
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
| | - Maria Grazia Cusi
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (G.A.); (C.G.); (S.P.); (M.G.C.)
- S. Maria delle Scotte Hospital, V.le Bracci, 1, 53100 Siena, Italy
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Experimental Infection of Dogs with Toscana Virus and Sandfly Fever Sicilian Virus to Determine Their Potential as Possible Vertebrate Hosts. Microorganisms 2020; 8:microorganisms8040596. [PMID: 32326097 PMCID: PMC7232252 DOI: 10.3390/microorganisms8040596] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 02/06/2023] Open
Abstract
The sandfly-borne Toscana phlebovirus (TOSV), a close relative of the sandfly fever Sicilian phlebovirus (SFSV), is one of the most common causes of acute meningitis or meningoencephalitis in humans in the Mediterranean Basin. However, most of human phlebovirus infections in endemic areas either are asymptomatic or cause mild influenza-like illness. To date, a vertebrate reservoir for sandfly-borne phleboviruses has not been identified. Dogs are a prime target for blood-feeding phlebotomines and are the primary reservoir of human sandfly-borne Leishmania infantum. However, there are no definitive studies to assess whether dogs play a significant role as a reservoir host for human phlebovirus survival in the environment. Here, we have evaluated the susceptibility of domestic dogs to infection by TOSV and SFSV following the direct inoculation of the infectious virus. After experimental infection, the presence of viral RNA was investigated in plasma, urine, saliva, conjunctiva, faeces, semen, and bone marrow samples from 0 to 91 days postinoculation (dpi), as well as in plasma, saliva, and tears samples at 760 dpi. None of the challenged dogs developed clinical signs of infection with either TOSV or SFSV. SFSV RNA was never detected. TOSV RNA was not in any of the specimen types, except for plasma samples that showed low viral loads, although irregularly. None of the dogs developed detectable neutralizing antibodies after a single challenge dose of either TOSV or SFSV. However, a second challenge dose of virus given 56 days later elicited neutralizing antibodies, implying that the first inoculation of virus primed the animals for an anamnestic response following the second challenge. These results demonstrated that healthy domestic dogs are not highly susceptible to infection by TOSV or SFSV and do not develop significant viremia or excrete virus following infection. Consequently, dogs are unlikely natural reservoir hosts of infection and do not appear to play a significant role in phlebovirus transmission cycles.
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Makranz C, Qutteineh H, Bin H, Lustig Y, Gomori JM, Honig A, Bayya AER, Moses AE, Ben-Hur T, Averbuch D, Eichel R, Nir-Paz R. Sandfly virus seroconversion associated with neurologic presentation. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2015; 3:e184. [PMID: 26767189 PMCID: PMC4701137 DOI: 10.1212/nxi.0000000000000184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 10/20/2015] [Indexed: 12/05/2022]
Abstract
Objective: To describe the clinical presentation and unique neurologic manifestations of sandfly viruses (SFVs) in the Jerusalem area. Methods: We identified all patients with acute seroconversion to SFV at the Hadassah-Hebrew University Medical Centers during the years 2008–2013 and retrospectively collected and analyzed the clinical and imaging data. Results: Nine patients (ranging from 1.5 to 85 years old) were identified. Presentation included acute neurologic disease, mostly with fever, change in consciousness and behavior, seizures, headache, meningitis, limb paresis, or myelitis. Eight patients had clinical signs of meningitis, meningoencephalitis, or encephalitis alone. Four patients had myelitis. MRI identified pathologic symmetrical changes in the basal ganglia, thalami, and other deep structures in 5 patients, and additional myelitis of the spine was noted on imaging in 3 patients. Seven patients had long-term follow-up: 4 completely recovered and 3 had remaining neurologic sequelae, among them 1 with permanent severe brain damage. Conclusion: Neurologic involvement associated with acute SFV infections is considered to be benign. However, in this series, all 9 patients presented with significant neurologic pathology associated with a unique finding of myelitis and symmetrical basal ganglia, thalami, or white matter involvement. Thus, acute SFV infection should be included in the differential diagnosis in febrile onset of neurologic manifestations and neuroradiologic changes.
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Affiliation(s)
- Chen Makranz
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Hiba Qutteineh
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Hanna Bin
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Yaniv Lustig
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - John Moshe Gomori
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Asaf Honig
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Abed El-Raouf Bayya
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Allon E Moses
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Tamir Ben-Hur
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Diana Averbuch
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Roni Eichel
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
| | - Ran Nir-Paz
- Departments of Neurology (C.M., A.H., T.B.-H., R.E.), Pediatrics (H.Q., D.A.), Radiology (J.M.G.), Medicine (A.E.-R.B.), and Clinical Microbiology and Infectious Diseases (A.E.M., R.N.-P.), Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Israel Central Virology Lab (H.B., Y.L.), Ministry of Health, Tel Hashomer, Israel
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Toscana virus infects dendritic and endothelial cells opening the way for the central nervous system. J Neurovirol 2015; 22:307-15. [PMID: 26510872 DOI: 10.1007/s13365-015-0395-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 10/06/2015] [Accepted: 10/12/2015] [Indexed: 02/06/2023]
Abstract
Toscana virus (TOSV) is a Phlebovirus responsible for human neurological infections in endemic Mediterranean areas. The main viral target is the central nervous system, with viremia as a way of dissemination throughout the host. This study was aimed at understanding the spread of TOSV in the host by identifying the cell population infected by the virus and the vehicle to the organs. In vivo studies provided evidence that endothelial cells are infected by TOSV, indicating their potential role in the diffusion of the virus following viremic spread. These results were further confirmed in vitro. Human peripheral mononuclear blood cells were infected with TOSV; only monocyte-derived dendritic cells were identified as susceptible to TOSV infection. Productive viral replication was then observed in human monocyte-derived dendritic cells (moDCs) and in human endothelial cells by recovery of the virus from a cell supernatant. Interleukin-6 was produced by both cell types upon TOSV infection, mostly by endothelial cells, while moDCs particularly expressed TNF-α, which is known to induce a long-lasting decrease in endothelial cell barrier function. These cells could therefore be implicated in the spread of the virus in the host and in the infection of tissues that are affected by the disease, such as the central nervous system. The identification of in vitro and in vivo TOSV cell targets is an important tool for understanding the pathogenesis of the infection, providing new insight into virus-cell interaction for improved knowledge and control of this viral disease.
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10
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Dincer E, Gargari S, Ozkul A, Ergunay K. Potential animal reservoirs of Toscana virus and coinfections with Leishmania infantum in Turkey. Am J Trop Med Hyg 2015; 92:690-7. [PMID: 25711610 DOI: 10.4269/ajtmh.14-0322] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 01/16/2015] [Indexed: 01/09/2023] Open
Abstract
Toscana virus (TOSV), a sandfly-borne phlebovirus, is an important agent of human meningoencephalitis in the Mediterranean region, for which vertebrates acting as reservoirs have not yet been determined. This study investigates TOSV and Leishmania infections in dogs, cats, sheep, and goats from Adana and Mersin provinces in southeastern Turkey. TOSV neutralizing antibodies were demonstrated in 40.4% of the dog and 4% of the goat samples. TOSV RNA was detected in 9.9% of the 252 samples that mainly comprise dogs (96%). Thus, canine species can be suggested as the candidate reservoirs of TOSV. Partial sequences revealed the activity of TOSV genotypes A and B. In two dogs presenting with symptoms of canine leishmaniasis, infections of TOSV genotype B and Leishmania infantum have been documented, describing the first report of coinfections with these agents.
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Affiliation(s)
- Ender Dincer
- Mersin University Advanced Technology Education, Research and Application Center, Mersin, Turkey; Ankara University Faculty of Veterinary Medicine, Department of Virology, Ankara, Turkey; Hacettepe University Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, Turkey
| | - Sepandar Gargari
- Mersin University Advanced Technology Education, Research and Application Center, Mersin, Turkey; Ankara University Faculty of Veterinary Medicine, Department of Virology, Ankara, Turkey; Hacettepe University Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, Turkey
| | - Aykut Ozkul
- Mersin University Advanced Technology Education, Research and Application Center, Mersin, Turkey; Ankara University Faculty of Veterinary Medicine, Department of Virology, Ankara, Turkey; Hacettepe University Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, Turkey
| | - Koray Ergunay
- Mersin University Advanced Technology Education, Research and Application Center, Mersin, Turkey; Ankara University Faculty of Veterinary Medicine, Department of Virology, Ankara, Turkey; Hacettepe University Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara, Turkey
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11
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Alkan C, Bichaud L, de Lamballerie X, Alten B, Gould EA, Charrel RN. Sandfly-borne phleboviruses of Eurasia and Africa: Epidemiology, genetic diversity, geographic range, control measures. Antiviral Res 2013; 100:54-74. [DOI: 10.1016/j.antiviral.2013.07.005] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/03/2013] [Accepted: 07/09/2013] [Indexed: 12/12/2022]
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12
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Toscana virus NSs protein promotes degradation of double-stranded RNA-dependent protein kinase. J Virol 2013; 87:3710-8. [PMID: 23325696 DOI: 10.1128/jvi.02506-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toscana virus (TOSV), which is transmitted by Phlebotomus spp. sandflies, is a major etiologic agent of aseptic meningitis and encephalitis in the Mediterranean. Like other members of the genus Phlebovirus of the family Bunyaviridae, TOSV encodes a nonstructural protein (NSs) in its small RNA segment. Although the NSs of Rift Valley fever virus (RVFV) has been identified as an important virulence factor, which suppresses host general transcription, inhibits transcription from the beta interferon promoter, and promotes the proteasomal degradation of double-stranded RNA-dependent protein kinase (PKR), little is known about the functions of NSs proteins encoded by less-pathogenic members of this genus. In this study we report that TOSV is able to downregulate PKR with similar efficiency as RVFV, while infection with the other phleboviruses-i.e., Punta Toro virus, sandfly fever Sicilian virus, or Frijoles virus-has no effect on cellular PKR levels. In contrast to RVFV, however, cellular transcription remains unaffected during TOSV infection. TOSV NSs protein promotes the proteasome-dependent downregulation of PKR and is able to interact with kinase-inactive PKR in infected cells.
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13
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Charrel RN, Bichaud L, de Lamballerie X. Emergence of Toscana virus in the mediterranean area. World J Virol 2012; 1:135-41. [PMID: 24175218 PMCID: PMC3782275 DOI: 10.5501/wjv.v1.i5.135] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Revised: 09/18/2012] [Accepted: 10/10/2012] [Indexed: 02/05/2023] Open
Abstract
Toscana virus (TOSV) is an arthropod-borne virus, identified in 1971, from Phlebotomus perniciosus and Phlebotomus perfiliewi in central Italy. TOSV belongs to the Phlebovirus genus within the Bunyaviridae family. As other bunyaviruses, the genome of TOSV consists of 3 segments (S for small, M for Medium, and L for Large) respectively encoding non structural and capsid proteins, envelope structural proteins, and the viral RNA-dependant RNA-polymerase. It is transmitted by sand flies. Therefore its distribution is dictated by that of the arthropod vectors, and virus circulation peaks during summertime when sandfly populations are active. Here, we reviewed the epidemiology of TOSV in the old world. First evidence of its pathogenicity for humans, specifically its propensity to cause central nervous system (CNS) infections such as meningitis and encephalitis, was reported in central Italy. After 2000, it was recognized that TOSV had a much larger geographic distribution than initially believed, and was present in most of the Western European countries located on the northern border of the Mediterranean Sea (Portugal, Spain, France, Greece, Croatia) as well as eastern countries such as Cyprus and Turkey. In the countries where TOSV is present, it is among the three most prevalent viruses in meningitis during the warm seasons, together with enteroviruses and herpesviruses. Up to now, epidemiological data concerning Northern Africa and other countries located south of the Mediterranean are scarce. TOSV must be considered an emerging pathogen. Despite the important role played by TOSV in CNS infections, it remains a neglected agent and is rarely considered by physicians in diagnostic algorithms of CNS infections and febrile illness during the warm season, probably because of the lack of information.
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Affiliation(s)
- Remi N Charrel
- Remi N Charrel, Laurence Bichaud, Xavier de Lamballerie, Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, UMR_D 190 "Emergence des Pathologies Virales", 13005 Marseille, France
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14
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Pathogenesis of emerging severe fever with thrombocytopenia syndrome virus in C57/BL6 mouse model. Proc Natl Acad Sci U S A 2012; 109:10053-8. [PMID: 22665769 DOI: 10.1073/pnas.1120246109] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The discovery of an emerging viral disease, severe fever with thrombocytopenia syndrome (SFTS), caused by SFTS virus (SFTSV), has prompted the need to understand pathogenesis of SFTSV. We are unique in establishing an infectious model of SFTS in C57/BL6 mice, resulting in hallmark symptoms of thrombocytopenia and leukocytopenia. Viral RNA and histopathological changes were identified in the spleen, liver, and kidney. However, viral replication was only found in the spleen, which suggested the spleen to be the principle target organ of SFTSV. Moreover, the number of macrophages and platelets were largely increased in the spleen, and SFTSV colocalized with platelets in cytoplasm of macrophages in the red pulp of the spleen. In vitro cellular assays further revealed that SFTSV adhered to mouse platelets and facilitated the phagocytosis of platelets by mouse primary macrophages, which in combination with in vivo findings, suggests that SFTSV-induced thrombocytopenia is caused by clearance of circulating virus-bound platelets by splenic macrophages. Thus, this study has elucidated the pathogenic mechanisms of thrombocytopenia in a mouse model resembling human SFTS disease.
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15
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Histological description of the lymphadenopathy related to Toscana virus infection. Report of a case. Pathol Res Pract 2011; 207:197-201. [DOI: 10.1016/j.prp.2010.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 04/13/2010] [Accepted: 07/23/2010] [Indexed: 11/18/2022]
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16
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Serata D, Rapinesi C, Del Casale A, Simonetti A, Mazzarini L, Ambrosi E, Kotzalidis GD, Fensore C, Girardi P, Tatarelli R. Personality Changes After Toscana Virus (TOSV) Encephalitis in a 49-Year-Old Man: A Case Report. Int J Neurosci 2010; 121:165-9. [DOI: 10.3109/00207454.2010.537412] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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17
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Li G, Ren J, Xu F, Ferguson MR. Non-structural and nucleocapsid proteins of Punta Toro virus induce apoptosis of hepatocytes through both intrinsic and extrinsic pathways. Microbiol Immunol 2010; 54:20-30. [PMID: 20055939 DOI: 10.1111/j.1348-0421.2009.00178.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Punta Toro virus (PTV; family Bunyaviridae, genus Phlebovirus) causes severe hepatic damage through brisk apoptosis of hepatocytes. In the present study, two viral proteins encoded by the S segment of the viral genome, non-structural (NSs) and nucleocapsid protein (N), were examined for their roles in apoptosis. Expression of NSs in HepG2 cells led to apoptosis in 45% of transfected cells, and with N, 28%, on average. These levels represent a four- to an eightfold increase over cells transfected with the mutated protein vectors. Caspase-3, -8 and -9 activities were increased by N protein when compared with the control NC (P < 0.05), and by NSsA and NSsB, as compared to control NSsC (P < 0.01). Treatment of the transfected cells with caspase-8 or -9 inhibitors markedly decreased apoptosis. Neutralization of TNF-alpha or Fas ligand had no effect on apoptosis. These results indicate that both NSs and N are responsible for causing hepatocyte apoptosis by triggering the extrinsic caspase-8 and intrinsic caspase-9 pathways.
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Affiliation(s)
- Guangyu Li
- Department of Internal Medicine and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas 77550-0609, USA.
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18
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Xu F, Liang X, Tesh RB, Xiao SY. Characterization of cell-death pathways in Punta Toro virus-induced hepatocyte injury. J Gen Virol 2008; 89:2175-2181. [PMID: 18753227 DOI: 10.1099/vir.0.2008/001644-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Punta Toro virus (PTV; genus Phlebovirus, family Bunyaviridae) causes apoptosis of hepatocytes in vivo in experimentally infected hamsters and in vitro in cultured HepG2 cells. Screening for expression of apoptosis-related genes has shown alterations in the genes for tumour necrosis factor-alpha (TNF-alpha) and the TNF receptor family. This study examined the roles of the TNF receptor-related extrinsic pathway and the Bcl-2 family-associated mitochondrial pathway in PTV-induced cell death. The effects of caspase inhibitors (caspIs) and TNF on cellular viability, virus replication, and morphological and biochemical changes in apoptosis were examined in HepG2 cells at different time points after infection with PTV (Adames strain). The results showed that caspIs dampened the virus-induced reduction in cellular viability, partially suppressed and delayed viral titres and antigen expression, and partially decreased the expression of apoptotic genes, caspase activities and DNA fragmentation. TNF treatment further decreased cellular viability after PTV infection and increased the level of apoptosis, whilst caspIs partially inhibited these effects. These findings indicate that TNF, caspase-8 and caspase-9 contribute to PTV-induced hepatocytic apoptosis and that additional mediators are probably also involved in this process. These mediators from different pathways correlated with one another and may be interlinked.
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Affiliation(s)
- Fangling Xu
- Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Xiaodong Liang
- Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Robert B Tesh
- Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Shu-Yuan Xiao
- Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
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19
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Immunization with Toscana virus N-Gc proteins protects mice against virus challenge. Virology 2008; 375:521-8. [PMID: 18355889 DOI: 10.1016/j.virol.2008.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 12/21/2007] [Accepted: 02/08/2008] [Indexed: 11/22/2022]
Abstract
Toscana virus (TOSV) is an emerging virus, circulating in the Mediterranean area, that is responsible for aseptic meningitis, meningoencephalitis, and encephalitis. The development of a vaccine that could provide complete protection from TOSV infection is needed. In this study we investigated the capacity of TOSV structural proteins, nucleocapsid protein N and the two Gc and Gn glycoproteins, produced as recombinant proteins, in an animal model. In particular, we investigated their role in inducing specific and protective immune responses against virus infection. Mice were immunized intraperitoneally using TOSV antigens singly or in combination. The results show that only the N-Gc combination was able to protect 100% of animals from a lethal challenge with a neurovirulent strain of TOSV. This potential vaccine induces high serum antibody titres with neutralizing activity and it is safe for animals. Moreover, immunization induces a virus specific cell-mediated immune response, in particular a CD8+ T cell response associated with a marked expression of interferon gamma. These results indicate that the N+Gc viral antigen combination could be useful for future development of a vaccine controlling the spread of this emerging virus that could pose a new threat for humans.
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20
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Perrone LA, Narayanan K, Worthy M, Peters CJ. The S segment of Punta Toro virus (Bunyaviridae, Phlebovirus) is a major determinant of lethality in the Syrian hamster and codes for a type I interferon antagonist. J Virol 2007; 81:884-92. [PMID: 17050607 PMCID: PMC1797479 DOI: 10.1128/jvi.01074-06] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Accepted: 10/05/2006] [Indexed: 01/20/2023] Open
Abstract
Two strains of Punta Toro virus (PTV), isolated from febrile humans in Panama, cause a differential pathogenesis in Syrian hamsters, which could be a useful model for understanding the virulence characteristics and differential outcomes in other phleboviral infections such as Rift Valley fever virus. Genetic reassortants produced between the lethal Adames (A/A/A) and nonlethal Balliet (B/B/B) strains were used in this study to investigate viral genetic determinants for pathogenesis and lethality in the hamster model. The S segment was revealed to be a critical genome segment, determining lethality with log(10) 50% lethal doses for each PTV genotype as follows (L/M/S convention): A/A/A, <0.7; B/A/A, <0.7; A/B/A, 1.5; B/B/A, 2.2; B/A/B, 4.7; A/B/B, >4.7; A/A/B, >4.7; B/B/B, >4.7. In addition, the Adames strain inhibits the induction of alpha/beta interferon (IFN-alpha/beta) in vivo and in vitro and inhibits the activation of the IFN-beta promoter. Expression of the PTV Adames NSs protein, encoded by the S RNA segment, inhibited the virus-mediated induction of an IFN-beta promoter-driven reporter gene, suggesting that PTV NSs functions as a type I IFN antagonist. Taken together, these data indicate a mechanism of pathogenesis in which the suppression of the type I IFN response early during PTV infection leads to early and uncontrolled viral replication and, ultimately, hamster death. This study contributes to our understanding of Phlebovirus pathogenesis and identifies potential targets for immune modulation to increase host survival.
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Affiliation(s)
- Lucy A Perrone
- Department of Pathology, Centers for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas 77550-0609, USA
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Charrel RN, Gallian P, Navarro-Mari JM, Nicoletti L, Papa A, Sánchez-Seco MP, Tenorio A, de Lamballerie X. Emergence of Toscana virus in Europe. Emerg Infect Dis 2006; 11:1657-63. [PMID: 16318715 PMCID: PMC3367371 DOI: 10.3201/eid1111.050869] [Citation(s) in RCA: 197] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
In southern Europe, Toscana virus is one of the three leading causes of aseptic meningitis. Toscana virus (TOSV) is an arthropodborne virus first identified in 1971 from the sandfly Phlebotomus perniciosus in central Italy. Many case reports in travelers and clinical research and epidemiologic studies conducted around the Mediterranean region have shown that TOSV has a tropism for the central nervous system (CNS) and is a major cause of meningitis and encephalitis in countries in which it circulates. In central Italy, TOSV is the most frequent cause of meningitis from May to October, far exceeding enteroviruses. In other northern Mediterranean countries, TOSV is among the 3 most prevalent viruses associated with meningitis during the warm seasons. Therefore, TOSV must be considered an emerging pathogen. Here, we review the epidemiology of TOSV in Europe and determine questions that should be addressed in future studies. Despite increasing evidence of its major role in medicine as an emerging cause of CNS infections, TOSV remains an unstudied pathogen, and few physicians are aware of its potential to cause CNS infections.
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Affiliation(s)
- Rémi N Charrel
- Unité des Virus Emergents, Faculté de Médecine, Université de la Méditerranée, 27 boulevard Jean Moulin, 13005 Marseille, France.
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Ding X, Xu F, Chen H, Tesh RB, Xiao SY. Apoptosis of hepatocytes caused by Punta Toro virus (Bunyaviridae: Phlebovirus) and its implication for Phlebovirus pathogenesis. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 167:1043-9. [PMID: 16192639 PMCID: PMC1603669 DOI: 10.1016/s0002-9440(10)61193-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Experimental infection of hamsters with Punta Toro virus (PTV) produces a disease with clinical and pathological similarities to the severe human hemorrhagic fever caused by Rift Valley fever virus (RVFV), thus providing an animal model for RVFV pathogenesis. In this model, hepatocytic apoptosis is the main pathological component of liver injuries that are responsible for severe hemorrhagic manifestations. To further elucidate whether viral replication in hepatocytes directly causes apoptosis, we studied the morphological and biochemical changes of apoptosis in HepG2 cells at different time points after PTV infection. Cellular viability began to decrease 12 hours after infection compared with controls. Caspases 3/7 were activated significantly at 48 and 72 hours after infection, and phosphatidylserine translocation and DNA fragmentation were also detected at 48 and 72 hours. Cell cycle analysis by flow cytometry showed that infected HepG2 cells were arrested at G(0)/G(1) phase. Furthermore, virus titer increased with apoptosis progression, suggesting that viral replication is necessary for the apoptotic process. These results indicate that PTV infection alone, without a secondary inflammatory cellular reaction, induces hepatocytic apoptosis and suggest that future therapeutics for RVFV hemorrhagic disease might target inhibition of cellular apoptotic pathways during the acute infection.
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Affiliation(s)
- Xiaohua Ding
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0588, USA
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