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Rémi N. Charrel - One of the best experts on this subject based on the ideXlab platform.
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seroprevalence of toscana virus and sandfly fever sicilian virus in european bat colonies measured using a neutralization test
Viruses, 2021Co-Authors: Nazli Ayhan, Rémi N. Charrel, Marc Lopezroig, Abir Monastiri, Jordi SerracoboAbstract:Toscana Phlebovirus (TOSV) and Sicilian Phlebovirus (SFSV) are endemic in the Mediterranean area where they are transmitted to humans by infected sandflies. Vertebrates of several species have been postulated to act as reservoirs of these viruses, but convincing evidence is still awaited. Among them, bats have been suggested, however documented evidence is lacking. Here we tested a total of 329 bats belonging to eight species collected from twelve localities in southern Spain for the presence of neutralizing antibodies specific to TOSV and SFSV. Positive sera were detected in Schreiber's long-fingered bat (Miniopterus schreibersii), mouse-eared Myotis (Myotis myotis), European free-tailed bat (Tadarida teniotis), and common serotine (Eptesicus serotinus) with the latter showing the highest prevalence rates for SFSV (22.6%) and TOSV (10%). There was no difference between females and males. Results suggest that bats are not likely to play a major role in the natural cycle of these two sandfly-borne Phleboviruses. However, large breeding colonies of bats can be used as sentinels for surveillance of the presence of such viruses in a given locality. In addition, capture-recapture studies should be initiated in order to understand better the dynamics of TOSV and SFSV in bat populations.
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Detection of Leishmania infantum and a Novel Phlebovirus (Balkan Virus) from Sand Flies in Albania.
Vector borne and zoonotic diseases (Larchmont N.Y.), 2016Co-Authors: Nazli Ayhan, Yusuf Ozbel, Rémi N. Charrel, Enkelejda Velo, Xavier De Lamballerie, Majlinda Kota, Perparim Kadriaj, Silvia BinoAbstract:Abstract Objective: To organize entomological campaigns to trap sand flies in selected regions of Albania and to test them for the presence of existing or new Phleboviruses and for leishmania DNA. Methods: Sand flies were collected in 14 locations from May to October 2014 using three different types of traps. Pools with a maximum of 30 individuals were prepared according to gender, trapping site, and trapping date; they were tested for the presence of (1) Phlebovirus RNA with three different PCR systems (2) and Leishmania DNA using two different real-time PCR assays. Results: A total of 972 sand flies (568 females, 404 males) were aliquoted to 55 pools. Three pools (in two different regions) were positive for Leishmania infantum. Two pools (Kruje region) were positive for Phlebovirus RNA and a 575-nucleotide (nt) colinearized sequence of a novel virus most closely related to but clearly distinct from Tehran virus (16% and 3% divergence at nt and amino acid levels). Next generation sequencing analysis indi...
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complete coding sequences of six toscana virus strains isolated from human patients in france
Genome Announcements, 2016Co-Authors: Amal Baklouti, Bruno Coutard, Nicolas Papageorgiou, Geraldine Piorkowski, Xavier De Lamballerie, Isabelle Leparcgoffart, Rémi N. CharrelAbstract:ABSTRACT Toscana virus (TOSV) is an arthropod-borne Phlebovirus belonging to the Sandfly fever Naples virus species (genus Phlebovirus, family Bunyaviridae). Here, we report the complete coding sequences of six TOSV strains isolated from human patients having acquired the infection in southeastern France during a 12-year period.
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complete coding sequences of three toscana virus strains isolated from sandflies in france
Genome Announcements, 2016Co-Authors: Amal Baklouti, Bruno Coutard, Nicolas Papageorgiou, Geraldine Piorkowski, Xavier De Lamballerie, Isabelle Leparc Goffard, Rémi N. CharrelAbstract:ABSTRACT Toscana virus (TOSV) is an arthropod-borne virus belonging to the sandfly fever Naples virus species within the genus Phlebovirus. We report here the complete coding sequences of three TOSV strains belonging to lineage B and isolated from sandflies trapped in the Southeast of France between 2009 and 2013.
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Comparative Production Analysis of Three Phlebovirus Nucleoproteins under Denaturing or Non-Denaturing Conditions for Crystallographic Studies
PLoS neglected tropical diseases, 2011Co-Authors: Violaine Lantez, Bruno Canard, Rémi N. Charrel, Karen Dalle, Cécile Baronti, Bruno CoutardAbstract:Nucleoproteins (NPs) encapsidate the Phlebovirus genomic (-)RNA. Upon recombinant expression, NPs tend to form heterogeneous oligomers impeding characterization of the encapsidation process through crystallographic studies. To overcome this problem, we set up a standard protocol in which production under both non-denaturing and denaturing/refolding conditions can be investigated and compared. The protocol was applied for three Phlebovirus NPs, allowing an optimized production strategy for each of them. Remarkably, the Rift Valley fever virus NP was purified as a trimer under native conditions and yielded protein crystals whereas the refolded version could be purified as a dimer. Yields of trimeric Toscana virus NP were higher from denaturing than from native condition and lead to crystals. The production of Sandfly Fever Sicilian virus NP failed in both protocols. The comparative protocols described here should help in rationally choosing between denaturing or non-denaturing conditions, which would finally result in the most appropriate and relevant oligomerized protein species. The structure of the Rift Valley fever virus NP has been recently published using a refolded monomeric protein and we believe that the process we devised will contribute to shed light in the genome encapsidation process, a key stage in the viral life cycle.
Michele Bouloy - One of the best experts on this subject based on the ideXlab platform.
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Rift Valley fever virus.
Current Molecular Medicine, 2005Co-Authors: Ramon Flick, Michele BouloyAbstract:Rift Valley fever is considered to be one of the most important viral zoonoses in Africa. In 2000, the Rift valley fever virus spread to the Arabian Peninsula and caused two simultaneous outbreaks in Yemen and Saudi Arabia. It is transmitted to ruminants and to humans by mosquitoes. The viral agent is an arbovirus, which belongs to the Phlebovirus genus in the Bunyaviridae family. This family of viruses comprises more than 300 members grouped into five genera: Orthobunyavirus, Phlebovirus, Hantavirus, Nairovirus, and Tospovirus. Several members of the Bunyaviridae family are responsible for fatal hemorrhagic fevers: Rift Valley fever virus (Phlebovirus), Crimean-Congo hemorrhagic fever virus (Nairovirus), Hantaan, Sin Nombre and related viruses (Hantavirus), and recently Garissa, now identified as Ngari virus (Orthobunyavirus). Here are reviewed recent advances in Rift Valley fever virus, its epidemiology, molecular biology and focus on recent data on the interactions between viral and cellular proteins, which help to understand the molecular mechanisms utilized by the virus to circumvent the host cellular response.
Nicolas Fasel - One of the best experts on this subject based on the ideXlab platform.
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amazonian Phlebovirus bunyaviridae potentiates the infection of leishmania leishmania amazonensis role of the pkr ifn1 il 10 axis
PLOS Neglected Tropical Diseases, 2019Co-Authors: Carolina Torturella Rath, Laila C Schnellrath, Clarissa R Damaso, Luciana Barros De Arruda, Pedro Fernando Da Costa Vasconcelos, Claudia M C Gomes, Marcia Dalastra Laurenti, Teresa Cristina Calegari Silva, Aislan De Carvalho Vivarini, Nicolas FaselAbstract:Leishmania parasites are transmitted to vertebrate hosts by phlebotomine sandflies and, in humans, may cause tegumentary or visceral leishmaniasis. The role of PKR (dsRNA activated kinase) and Toll-like receptor 3 (TLR3) activation in the control of Leishmania infection highlights the importance of the engagement of RNA sensors, which are usually involved in the antiviral cell response, in the fate of parasitism by Leishmania. We tested the hypothesis that Phlebovirus, a subgroup of the Bunyaviridae, transmitted by sandflies, would interfere with Leishmania infection. We tested two Phlebovirus isolates, Icoaraci and Pacui, from the rodents Nectomys sp. and Oryzomys sp., respectively, both natural sylvatic reservoir of Leishmania (Leishmania) amazonensis from the Amazon region. Phlebovirus coinfection with L. (L.) amazonensis in murine macrophages led to increased intracellular growth of L. (L.) amazonensis. Further studies with Icoaraci coinfection revealed the requirement of the PKR/IFN1 axis on the exacerbation of the parasite infection. L. (L.) amazonensis and Phlebovirus coinfection potentiated PKR activation and synergistically induced the expression of IFNβ and IL-10. Importantly, in vivo coinfection of C57BL/6 mice corroborated the in vitro data. The exacerbation effect of RNA virus on parasite infection may be specific because coinfection with dengue virus (DENV2) exerted the opposite effect on parasite load. Altogether, our data suggest that coinfections with specific RNA viruses shared by vectors or reservoirs of Leishmania may enhance and sustain the activation of host cellular RNA sensors, resulting in aggravation of the parasite infection. The present work highlights new perspectives for the investigation of antiviral pathways as important modulators of protozoan infections.
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Amazonian Phlebovirus (Bunyaviridae) potentiates the infection of Leishmania (Leishmania) amazonensis: Role of the PKR/IFN1/IL-10 axis.
PLoS neglected tropical diseases, 2019Co-Authors: Carolina Torturella Rath, Laila C Schnellrath, Clarissa R Damaso, Luciana Barros De Arruda, Pedro Fernando Da Costa Vasconcelos, Claudia M C Gomes, Marcia Dalastra Laurenti, Teresa Cristina Calegari Silva, Aislan De Carvalho Vivarini, Nicolas FaselAbstract:Leishmania parasites are transmitted to vertebrate hosts by phlebotomine sandflies and, in humans, may cause tegumentary or visceral leishmaniasis. The role of PKR (dsRNA activated kinase) and Toll-like receptor 3 (TLR3) activation in the control of Leishmania infection highlights the importance of the engagement of RNA sensors, which are usually involved in the antiviral cell response, in the fate of parasitism by Leishmania. We tested the hypothesis that Phlebovirus, a subgroup of the Bunyaviridae, transmitted by sandflies, would interfere with Leishmania infection. We tested two Phlebovirus isolates, Icoaraci and Pacui, from the rodents Nectomys sp. and Oryzomys sp., respectively, both natural sylvatic reservoir of Leishmania (Leishmania) amazonensis from the Amazon region. Phlebovirus coinfection with L. (L.) amazonensis in murine macrophages led to increased intracellular growth of L. (L.) amazonensis. Further studies with Icoaraci coinfection revealed the requirement of the PKR/IFN1 axis on the exacerbation of the parasite infection. L. (L.) amazonensis and Phlebovirus coinfection potentiated PKR activation and synergistically induced the expression of IFNβ and IL-10. Importantly, in vivo coinfection of C57BL/6 mice corroborated the in vitro data. The exacerbation effect of RNA virus on parasite infection may be specific because coinfection with dengue virus (DENV2) exerted the opposite effect on parasite load. Altogether, our data suggest that coinfections with specific RNA viruses shared by vectors or reservoirs of Leishmania may enhance and sustain the activation of host cellular RNA sensors, resulting in aggravation of the parasite infection. The present work highlights new perspectives for the investigation of antiviral pathways as important modulators of protozoan infections.
Gustavo Palacios - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the Salehabad virus species complex of the genus Phlebovirus (Bunyaviridae)
Journal of General Virology, 2013Co-Authors: Gustavo Palacios, Hilda Guzman, Nazir Savji, Amelia P. A. Travassos Da Rosa, Aaloki Desai, María Paz Sánchez-seco, W. Ian LipkinAbstract:Genomic and antigenic characterization of the Salehabad virus, a species of the genus Phlebovirus, and four other unclassified Phleboviruses (Arbia, Adria, Arumowot and Odrenisrou) demonstrate a serological and genetic relation to one another and are distinct from the eight other recognized species within the genus Phlebovirus. We propose to incorporate these four unclassified viruses as part of the Salehabad species complex within the genus. The known geographical distribution for the members of this species group includes southern Europe, Central Asia and Africa.
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Aguacate virus, a new antigenic complex of the genus Phlebovirus (family Bunyaviridae)
Journal of General Virology, 2011Co-Authors: Gustavo Palacios, Hilda Guzman, Nazir Savji, Amelia P. A. Travassos Da Rosa, Stephen K. Hutchison, Wilson Sze, Ivan Wick, W. Ian LipkinAbstract:Genomic and antigenic characterization of Aguacate virus, a tentative species of the genus Phlebovirus, and three other unclassified viruses, Armero virus, Durania virus and Ixcanal virus, demonstrate a close relationship to one another. They are distinct from the other nine recognized species within the genus Phlebovirus. We propose to designate them as a new (tenth) serogroup or species (Aguacate virus) within the genus. The four viruses were all isolated from phlebotomine sandflies (Lutzomyia sp.) collected in Central and South America. Aguacate virus appears to be a natural reassortant and serves as one more example of the high frequency of reassortment in this genus.
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Granada Virus: a Natural Phlebovirus Reassortant of the Sandfly Fever Naples Serocomplex with Low Seroprevalence in Humans
The American journal of tropical medicine and hygiene, 2010Co-Authors: Ximena Collao, Gustavo Palacios, Fernando De Ory, Sara Sanbonmatsu, Mercedes Pérez-ruiz, Ricardo Molina, Stephen K. Hutchison, Ian W. Lipkin, Antonio TenorioAbstract:A new member of the Phlebovirus genus, tentatively named Granada virus, was detected in sandflies collected in Spain. By showing the presence of specific neutralizing antibodies in human serum collected in Granada, we show that Granada virus infects humans. The analysis of the complete genome of Granada virus revealed that this agent is likely to be a natural reassortant of the recently described Massilia virus (donor of the long and short segments) with a yet unidentified Phlebovirus (donor of the medium segment).
Carolina Torturella Rath - One of the best experts on this subject based on the ideXlab platform.
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production quantification and infection of amazonian Phlebovirus bunyaviridae
Bio-protocol, 2021Co-Authors: Carolina Torturella Rath, Aislan De Carvalho Vivarini, Renata M Pereira, Ulisses Gazos LopesAbstract:Phlebotomine vectors, sand flies of the order Diptera, are known to transmit Leishmania parasites as well as RNA viruses (arboviruses) to humans. The arbovirus, Icoaraci Phlebovirus (BeAN 24262 - ICOV), used in this study was isolated from Nectomys rodents, a mammalian species that is the same natural sylvatic reservoir of Leishmania (Leishmania) amazonensis. This Leishmania species is distributed in primary and secondary forests in Brazil and other countries in America and causes localized and diffuse anergic skin lesions. In our recent studies, we observed an aggravation of the protozoan infection by ICOV through the modulation of cytokine expression, such as IL-10 and IFN-β, enhancing the parasite load and possibly the pathogenesis. Efficient viral production and quantitation had to be developed and standardized to ensure that immuno-molecular assays provide consistent and reproducible viral infection results. The standardization of these procedures becomes a particularly useful tool in research, with several applications in understanding the interaction between the host cell and Phlebovirus, as well as co-infections, allowing the study of intracellular signaling pathways. Here, we detail a protocol that allows the production and quantitation of the Icoaraci Phlebovirus using BHK-21 cells (baby hamster kidney cells) and subsequent infection of peritoneal macrophages from C57BL/6 mice.
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amazonian Phlebovirus bunyaviridae potentiates the infection of leishmania leishmania amazonensis role of the pkr ifn1 il 10 axis
PLOS Neglected Tropical Diseases, 2019Co-Authors: Carolina Torturella Rath, Laila C Schnellrath, Clarissa R Damaso, Luciana Barros De Arruda, Pedro Fernando Da Costa Vasconcelos, Claudia M C Gomes, Marcia Dalastra Laurenti, Teresa Cristina Calegari Silva, Aislan De Carvalho Vivarini, Nicolas FaselAbstract:Leishmania parasites are transmitted to vertebrate hosts by phlebotomine sandflies and, in humans, may cause tegumentary or visceral leishmaniasis. The role of PKR (dsRNA activated kinase) and Toll-like receptor 3 (TLR3) activation in the control of Leishmania infection highlights the importance of the engagement of RNA sensors, which are usually involved in the antiviral cell response, in the fate of parasitism by Leishmania. We tested the hypothesis that Phlebovirus, a subgroup of the Bunyaviridae, transmitted by sandflies, would interfere with Leishmania infection. We tested two Phlebovirus isolates, Icoaraci and Pacui, from the rodents Nectomys sp. and Oryzomys sp., respectively, both natural sylvatic reservoir of Leishmania (Leishmania) amazonensis from the Amazon region. Phlebovirus coinfection with L. (L.) amazonensis in murine macrophages led to increased intracellular growth of L. (L.) amazonensis. Further studies with Icoaraci coinfection revealed the requirement of the PKR/IFN1 axis on the exacerbation of the parasite infection. L. (L.) amazonensis and Phlebovirus coinfection potentiated PKR activation and synergistically induced the expression of IFNβ and IL-10. Importantly, in vivo coinfection of C57BL/6 mice corroborated the in vitro data. The exacerbation effect of RNA virus on parasite infection may be specific because coinfection with dengue virus (DENV2) exerted the opposite effect on parasite load. Altogether, our data suggest that coinfections with specific RNA viruses shared by vectors or reservoirs of Leishmania may enhance and sustain the activation of host cellular RNA sensors, resulting in aggravation of the parasite infection. The present work highlights new perspectives for the investigation of antiviral pathways as important modulators of protozoan infections.
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Amazonian Phlebovirus (Bunyaviridae) potentiates the infection of Leishmania (Leishmania) amazonensis: Role of the PKR/IFN1/IL-10 axis.
PLoS neglected tropical diseases, 2019Co-Authors: Carolina Torturella Rath, Laila C Schnellrath, Clarissa R Damaso, Luciana Barros De Arruda, Pedro Fernando Da Costa Vasconcelos, Claudia M C Gomes, Marcia Dalastra Laurenti, Teresa Cristina Calegari Silva, Aislan De Carvalho Vivarini, Nicolas FaselAbstract:Leishmania parasites are transmitted to vertebrate hosts by phlebotomine sandflies and, in humans, may cause tegumentary or visceral leishmaniasis. The role of PKR (dsRNA activated kinase) and Toll-like receptor 3 (TLR3) activation in the control of Leishmania infection highlights the importance of the engagement of RNA sensors, which are usually involved in the antiviral cell response, in the fate of parasitism by Leishmania. We tested the hypothesis that Phlebovirus, a subgroup of the Bunyaviridae, transmitted by sandflies, would interfere with Leishmania infection. We tested two Phlebovirus isolates, Icoaraci and Pacui, from the rodents Nectomys sp. and Oryzomys sp., respectively, both natural sylvatic reservoir of Leishmania (Leishmania) amazonensis from the Amazon region. Phlebovirus coinfection with L. (L.) amazonensis in murine macrophages led to increased intracellular growth of L. (L.) amazonensis. Further studies with Icoaraci coinfection revealed the requirement of the PKR/IFN1 axis on the exacerbation of the parasite infection. L. (L.) amazonensis and Phlebovirus coinfection potentiated PKR activation and synergistically induced the expression of IFNβ and IL-10. Importantly, in vivo coinfection of C57BL/6 mice corroborated the in vitro data. The exacerbation effect of RNA virus on parasite infection may be specific because coinfection with dengue virus (DENV2) exerted the opposite effect on parasite load. Altogether, our data suggest that coinfections with specific RNA viruses shared by vectors or reservoirs of Leishmania may enhance and sustain the activation of host cellular RNA sensors, resulting in aggravation of the parasite infection. The present work highlights new perspectives for the investigation of antiviral pathways as important modulators of protozoan infections.
