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1.
PLoS Pathog ; 17(6): e1009636, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34166464

RESUMEN

Many viruses target signal transducers and activators of transcription (STAT) 1 and 2 to antagonise antiviral interferon signalling, but targeting of signalling by other STATs/cytokines, including STAT3/interleukin 6 that regulate processes important to Ebola virus (EBOV) haemorrhagic fever, is poorly defined. We report that EBOV potently inhibits STAT3 responses to interleukin-6 family cytokines, and that this is mediated by the interferon-antagonist VP24. Mechanistic analysis indicates that VP24 effects a unique strategy combining distinct karyopherin-dependent and karyopherin-independent mechanisms to antagonise STAT3-STAT1 heterodimers and STAT3 homodimers, respectively. This appears to reflect distinct mechanisms of nuclear trafficking of the STAT3 complexes, revealed for the first time by our analysis of VP24 function. These findings are consistent with major roles for global inhibition of STAT3 signalling in EBOV infection, and provide new insights into the molecular mechanisms of STAT3 nuclear trafficking, significant to pathogen-host interactions, cell physiology and pathologies such as cancer.


Asunto(s)
Fiebre Hemorrágica Ebola/metabolismo , Fiebre Hemorrágica Ebola/virología , Factor de Transcripción STAT3/antagonistas & inhibidores , Transducción de Señal/fisiología , Proteínas Virales/metabolismo , Animales , Chlorocebus aethiops , Ebolavirus , Células HEK293 , Humanos , Células Vero
2.
J Gen Virol ; 103(8)2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35972225

RESUMEN

Bats have been implicated as the reservoir hosts of filoviruses in Africa, with serological evidence of filoviruses in various bat species identified in other countries. Here, serum samples from 190 bats, comprising 12 different species, collected in Australia were evaluated for filovirus antibodies. An in-house indirect microsphere assay to detect antibodies that cross-react with Ebola virus (Zaire ebolavirus; EBOV) nucleoprotein (NP) followed by an immunofluorescence assay (IFA) were used to confirm immunoreactivity to EBOV and Reston virus (Reston ebolavirus; RESTV). We found 27 of 102 Yinpterochiroptera and 19 of 88 Yangochiroptera samples were positive to EBOV NP in the microsphere assay. Further testing of these NP positive samples by IFA revealed nine bat sera that showed binding to ebolavirus-infected cells. This is the first report of filovirus-reactive antibodies detected in Australian bat species and suggests that novel filoviruses may be circulating in Australian bats.


Asunto(s)
Quirópteros , Ebolavirus , Fiebre Hemorrágica Ebola , Animales , Anticuerpos Antivirales , Australia , Fiebre Hemorrágica Ebola/veterinaria , Nucleoproteínas
3.
PLoS Pathog ; 16(3): e1008412, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32226041

RESUMEN

Bats are the natural reservoir host for a number of zoonotic viruses, including Hendra virus (HeV) which causes severe clinical disease in humans and other susceptible hosts. Our understanding of the ability of bats to avoid clinical disease following infection with viruses such as HeV has come predominantly from in vitro studies focusing on innate immunity. Information on the early host response to infection in vivo is lacking and there is no comparative data on responses in bats compared with animals that succumb to disease. In this study, we examined the sites of HeV replication and the immune response of infected Australian black flying foxes and ferrets at 12, 36 and 60 hours post exposure (hpe). Viral antigen was detected at 60 hpe in bats and was confined to the lungs whereas in ferrets there was evidence of widespread viral RNA and antigen by 60 hpe. The mRNA expression of IFNs revealed antagonism of type I and III IFNs and a significant increase in the chemokine, CXCL10, in bat lung and spleen following infection. In ferrets, there was an increase in the transcription of IFN in the spleen following infection. Liquid chromatography tandem mass spectrometry (LC-MS/MS) on lung tissue from bats and ferrets was performed at 0 and 60 hpe to obtain a global overview of viral and host protein expression. Gene Ontology (GO) enrichment analysis of immune pathways revealed that six pathways, including a number involved in cell mediated immunity were more likely to be upregulated in bat lung compared to ferrets. GO analysis also revealed enrichment of the type I IFN signaling pathway in bats and ferrets. This study contributes important comparative data on differences in the dissemination of HeV and the first to provide comparative data on the activation of immune pathways in bats and ferrets in vivo following infection.


Asunto(s)
Antígenos Virales/inmunología , Virus Hendra/inmunología , Infecciones por Henipavirus/inmunología , Inmunidad Celular , Inmunidad Innata , Pulmón/inmunología , Modelos Inmunológicos , Animales , Antígenos Virales/genética , Quimiocina CXCL10/genética , Quimiocina CXCL10/inmunología , Quirópteros , Hurones , Virus Hendra/genética , Infecciones por Henipavirus/genética , Infecciones por Henipavirus/patología , Interferones/genética , Interferones/inmunología , Pulmón/patología , Pulmón/virología , Especificidad de la Especie
4.
Emerg Infect Dis ; 25(1): 166-170, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30561301

RESUMEN

Despite molecular and serologic evidence of Nipah virus in bats from various locations, attempts to isolate live virus have been largely unsuccessful. We report isolation and full-genome characterization of 10 Nipah virus isolates from Pteropus medius bats sampled in Bangladesh during 2013 and 2014.


Asunto(s)
Quirópteros/virología , Reservorios de Enfermedades/virología , Genoma Viral/genética , Infecciones por Henipavirus/veterinaria , Virus Nipah/genética , Animales , Bangladesh , Geografía , Infecciones por Henipavirus/virología , Humanos , Virus Nipah/aislamiento & purificación , Filogenia , Zoonosis
5.
J Virol ; 91(23)2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28931675

RESUMEN

Ebolavirus and Marburgvirus comprise two genera of negative-sense single-stranded RNA viruses that cause severe hemorrhagic fevers in humans. Despite considerable research efforts, the molecular events following Ebola virus (EBOV) infection are poorly understood. With the view of identifying host factors that underpin EBOV pathogenesis, we compared the transcriptomes of EBOV-infected human, pig, and bat kidney cells using a transcriptome sequencing (RNA-seq) approach. Despite a significant difference in viral transcription/replication between the cell lines, all cells responded to EBOV infection through a robust induction of extracellular growth factors. Furthermore, a significant upregulation of activator protein 1 (AP1) transcription factor complex members FOS and JUN was observed in permissive cell lines. Functional studies focusing on human cells showed that EBOV infection induces protein expression, phosphorylation, and nuclear accumulation of JUN and, to a lesser degree, FOS. Using a luciferase-based reporter, we show that EBOV infection induces AP1 transactivation activity within human cells at 48 and 72 h postinfection. Finally, we show that JUN knockdown decreases the expression of EBOV-induced host gene expression. Taken together, our study highlights the role of AP1 in promoting the host gene expression profile that defines EBOV pathogenesis.IMPORTANCE Many questions remain about the molecular events that underpin filovirus pathophysiology. The rational design of new intervention strategies, such as postexposure therapeutics, will be significantly enhanced through an in-depth understanding of these molecular events. We believe that new insights into the molecular pathogenesis of EBOV may be possible by examining the transcriptomic response of taxonomically diverse cell lines (derived from human, pig, and bat). We first identified the responsive pathways using an RNA-seq-based transcriptomics approach. Further functional and computational analysis focusing on human cells highlighted an important role for the AP1 transcription factor in mediating the transcriptional response to EBOV infection. Our study sheds new light on how host transcription factors respond to and promote the transcriptional landscape that follows viral infection.


Asunto(s)
Perfilación de la Expresión Génica , Fiebre Hemorrágica Ebola/virología , Interacciones Huésped-Patógeno , Factor de Transcripción AP-1/metabolismo , Animales , Línea Celular , Quirópteros , Ebolavirus/patogenicidad , Genes fos , Genes jun , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Riñón/citología , Riñón/virología , Fosforilación , Porcinos , Factor de Transcripción AP-1/genética , Proteínas Virales , Replicación Viral
6.
Virol J ; 15(1): 75, 2018 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-29685158

RESUMEN

BACKGROUND: The 2014/2015 Ebolavirus outbreak resulted in more than 28,000 cases and 11,323 reported deaths, as of March 2016. Domestic transmission of the Guinea strain associated with the outbreak occurred mainly in six African countries, and international transmission was reported in four countries. Outbreak management was limited by the inability to rapidly diagnose infected cases. A further fifteen countries in Africa are predicted to be at risk of Ebolavirus outbreaks in the future as a consequence of climate change and urbanization. Early detection of cases and reduction of transmission rates is critical to prevent and manage future severe outbreaks. We designed a rapid assay for detection of Ebolavirus using recombinase polymerase amplification, a rapid isothermal amplification technology that can be combined with portable lateral flow detection technology. The developed rapid assay operates in 30 min and was comparable with real-time TaqMan™ PCR. METHODS: Designed, screened, selected and optimized oligonucleotides using the NP coding region from Ebola Zaire virus (Guinea strain). We determined the analytical sensitivity of our Ebola rapid molecular test by testing selected primers and probe with tenfold serial dilutions (1.34 × 1010- 1.34 × 101 copies/µL) of cloned NP gene from Mayinga strain of Zaire ebolavirus in pCAGGS vector, and serially diluted cultured Ebolavirus as established by real-time TaqMan™ PCR that was performed using ABI7500 in Fast Mode. We tested extracted and reverse transcribed RNA from cultured Zaire ebolavirus strains - Mayinga, Gueckedou C05, Gueckedou C07, Makona, Kissidougou and Kiwit. We determined the analytical specificity of our assay with related viruses: Marburg, Ebola Reston and Ebola Sudan. We further tested for Dengue virus 1-4, Plasmodium falciparum and West Nile Virus (Kunjin strain). RESULTS: The assay had a detection limit of 134 copies per µL of plasmid containing the NP gene of Ebolavirus Mayinga, and cultured Ebolavirus and was highly specific for the Zaire ebolavirus species, including the Guinea strain responsible for the 2014/2015 outbreak. The assay did not detect related viruses like Marburg, Reston, or Sudan viruses, and other pathogens likely to be isolated from clinical samples. CONCLUSIONS: Our assay could be suitable for implementation in district and primary health laboratories, as only a heating block and centrifuge is required for operation. The technique could provide a pathway for rapid screening of patients and animals for improved management of outbreaks.


Asunto(s)
Ebolavirus/genética , Fiebre Hemorrágica Ebola/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico , Recombinasas , Línea Celular , Fiebre Hemorrágica Ebola/virología , Humanos , Proteínas de la Nucleocápside/genética , ARN Viral/análisis , ARN Viral/genética , Transcripción Reversa , Sensibilidad y Especificidad
7.
J Gen Virol ; 96(Pt 1): 24-29, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25228492

RESUMEN

Bats have been found to harbour a number of new emerging viruses with zoonotic potential, and there has been a great deal of interest in identifying novel bat pathogens to determine the risk to human and animal health. Many groups have identified novel viruses in bats by detection of viral nucleic acid; however, virus isolation is still a challenge, and there are few reports of viral isolates from bats. In recent years, our group has developed optimized procedures for virus isolation from bat urine, including the use of primary bat cells. In previous reports, we have described the isolation of Hendra virus, Menangle virus and Cedar virus in Queensland, Australia. Here, we report the isolation of four additional novel bat paramyxoviruses from urine collected from beneath pteropid bat (flying fox) colonies in Queensland and New South Wales during 2009-2011.


Asunto(s)
Quirópteros/virología , Paramyxovirinae/genética , Paramyxovirinae/aislamiento & purificación , Orina/virología , Animales , Australia , Infecciones por Paramyxoviridae/virología , Zoonosis/virología
8.
J Virol ; 87(3): 1348-58, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23152534

RESUMEN

Bats carry a variety of paramyxoviruses that impact human and domestic animal health when spillover occurs. Recent studies have shown a great diversity of paramyxoviruses in an urban-roosting population of straw-colored fruit bats in Ghana. Here, we investigate this further through virus isolation and describe two novel rubulaviruses: Achimota virus 1 (AchPV1) and Achimota virus 2 (AchPV2). The viruses form a phylogenetic cluster with each other and other bat-derived rubulaviruses, such as Tuhoko viruses, Menangle virus, and Tioman virus. We developed AchPV1- and AchPV2-specific serological assays and found evidence of infection with both viruses in Eidolon helvum across sub-Saharan Africa and on islands in the Gulf of Guinea. Longitudinal sampling of E. helvum indicates virus persistence within fruit bat populations and suggests spread of AchPVs via horizontal transmission. We also detected possible serological evidence of human infection with AchPV2 in Ghana and Tanzania. It is likely that clinically significant zoonotic spillover of chiropteran paramyxoviruses could be missed throughout much of Africa where health surveillance and diagnostics are poor and comorbidities, such as infection with HIV or Plasmodium sp., are common.


Asunto(s)
Quirópteros/virología , Infecciones por Rubulavirus/veterinaria , Infecciones por Rubulavirus/virología , Rubulavirus/clasificación , Rubulavirus/aislamiento & purificación , Zoonosis/epidemiología , Adolescente , Adulto , África/epidemiología , Animales , Anticuerpos Antivirales/sangre , Niño , Preescolar , Análisis por Conglomerados , Femenino , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Rubulavirus/genética , Rubulavirus/patogenicidad , Infecciones por Rubulavirus/epidemiología , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos
9.
PLoS Pathog ; 8(8): e1002836, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22879820

RESUMEN

The genus Henipavirus in the family Paramyxoviridae contains two viruses, Hendra virus (HeV) and Nipah virus (NiV) for which pteropid bats act as the main natural reservoir. Each virus also causes serious and commonly lethal infection of people as well as various species of domestic animals, however little is known about the associated mechanisms of pathogenesis. Here, we report the isolation and characterization of a new paramyxovirus from pteropid bats, Cedar virus (CedPV), which shares significant features with the known henipaviruses. The genome size (18,162 nt) and organization of CedPV is very similar to that of HeV and NiV; its nucleocapsid protein displays antigenic cross-reactivity with henipaviruses; and it uses the same receptor molecule (ephrin-B2) for entry during infection. Preliminary challenge studies with CedPV in ferrets and guinea pigs, both susceptible to infection and disease with known henipaviruses, confirmed virus replication and production of neutralizing antibodies although clinical disease was not observed. In this context, it is interesting to note that the major genetic difference between CedPV and HeV or NiV lies within the coding strategy of the P gene, which is known to play an important role in evading the host innate immune system. Unlike HeV, NiV, and almost all known paramyxoviruses, the CedPV P gene lacks both RNA editing and also the coding capacity for the highly conserved V protein. Preliminary study indicated that CedPV infection of human cells induces a more robust IFN-ß response than HeV.


Asunto(s)
Quirópteros/virología , Genoma Viral/inmunología , Infecciones por Henipavirus , Henipavirus , Evasión Inmune , Inmunidad Innata , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Australia , Quirópteros/inmunología , Hurones , Cobayas , Henipavirus/genética , Henipavirus/inmunología , Henipavirus/aislamiento & purificación , Infecciones por Henipavirus/sangre , Infecciones por Henipavirus/genética , Infecciones por Henipavirus/inmunología , Infecciones por Henipavirus/virología , Humanos
10.
Front Immunol ; 15: 1384417, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726013

RESUMEN

Nipah virus (NiV) poses a significant threat to human and livestock populations across South and Southeast Asia. Vaccines are required to reduce the risk and impact of spillover infection events. Pigs can act as an intermediate amplifying host for NiV and, separately, provide a preclinical model for evaluating human vaccine candidate immunogenicity. The aim of this study was therefore to evaluate the immunogenicity of an mRNA vectored NiV vaccine candidate in pigs. Pigs were immunized twice with 100 µg nucleoside-modified mRNA vaccine encoding soluble G glycoprotein from the Malaysia strain of NiV, formulated in lipid nanoparticles. Potent antigen-binding and virus neutralizing antibodies were detected in serum following the booster immunization. Antibody responses effectively neutralized both the Malaysia and Bangladesh strains of NiV but showed limited neutralization of the related (about 80% amino acid sequence identity for G) Hendra virus. Antibodies were also capable of neutralizing NiV glycoprotein mediated cell-cell fusion. NiV G-specific T cell cytokine responses were also measurable following the booster immunization with evidence for induction of both CD4 and CD8 T cell responses. These data support the further evaluation of mRNA vectored NiV G as a vaccine for both pigs and humans.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Infecciones por Henipavirus , Virus Nipah , Vacunas Virales , Animales , Virus Nipah/inmunología , Virus Nipah/genética , Porcinos , Infecciones por Henipavirus/prevención & control , Infecciones por Henipavirus/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/virología , ARN Mensajero/genética , ARN Mensajero/inmunología , Inmunogenicidad Vacunal , Inmunización Secundaria , Citocinas/inmunología , Vacunas Sintéticas/inmunología , Liposomas , Nanopartículas
11.
J Virol ; 86(15): 8014-30, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22623774

RESUMEN

Herpesviruses or herpesviral sequences have been identified in various bat species. Here, we report the isolation, cell tropism, and complete genome sequence of a novel betaherpesvirus from the bat Miniopterus schreibersii (MsHV). In primary cell culture, MsHV causes cytopathic effects (CPE) and reaches peak virus production 2 weeks after infection. MsHV was found to infect and replicate less efficiently in a feline kidney cell, CRFK, and failed to replicate in 13 other cell lines tested. Sequencing of the MsHV genome using the 454 system, with a 224-fold coverage, revealed a genome size of 222,870 bp. The genome was extensively analyzed in comparison to those of related viruses. Of the 190 predicted open reading frames (ORFs), 40 were identified as herpesvirus core genes. Among 93 proteins with identifiable homologues in tree shrew herpesvirus (THV), human cytomegalovirus (HCMV), or rat cytomegalovirus (RCMV), most had highest sequence identities with THV counterparts. However, the MsHV genome organization is colinear with that of RCMV rather than that of THV. The following unique features were discovered in the MsHV genome. One predicted protein, B125, is similar to human herpesvirus 6 (HHV-6) U94, a homologue of the parvovirus Rep protein. For the unique ORFs, 7 are predicted to encode major histocompatibility complex (MHC)-related proteins, 2 to encode MHC class I homologues, and 3 to encode MHC class II homologues; 4 encode the homologues of C-type lectin- or natural killer cell lectin-like receptors;, and the products of a unique gene family, the b149 family, of 16 members, have no significant sequence identity with known proteins but exhibit immunoglobulin-like beta-sandwich domains revealed by three-dimensional (3D) structural prediction. To our knowledge, MsHV is the first virus genome known to encode MHC class II homologues.


Asunto(s)
Genoma Viral , Herpesviridae/genética , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Lectinas Tipo C/genética , Sistemas de Lectura Abierta/genética , Proteínas Virales/genética , Animales , Gatos , Línea Celular , Quirópteros , Herpesviridae/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Ratas , Homología de Secuencia de Aminoácido , Proteínas Virales/metabolismo
12.
Virol J ; 10: 95, 2013 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-23521919

RESUMEN

BACKGROUND: Hendra virus (HeV) is an Australian bat-borne zoonotic paramyxovirus that repeatedly spills-over to horses causing fatal disease. Human cases have all been associated with close contact with infected horses. METHODS: A full-length antigenome clone of HeV was assembled, a reporter gene (GFP or luciferase) inserted between the P and M genes and transfected to 293T cells to generate infectious reporter gene-encoding recombinant viruses. These viruses were then assessed in vitro for expression of the reporter genes. The GFP expressing recombinant HeV was used to challenge ferrets to assess the virulence and tissue distribution by monitoring GFP expression in infected cells. RESULTS: Three recombinant HeV constructs were successfully cloned and rescued; a wild-type virus, a GFP-expressing virus and a firefly luciferase-expressing virus. In vitro characterisation demonstrated expression of the reporter genes, with levels proportional to the initial inoculum levels. Challenge of ferrets with the GFP virus demonstrated maintenance of the fatal phenotype with disease progressing to death consistent with that observed previously with the parental wild-type isolate of HeV. GFP expression could be observed in infected tissues collected from animals at euthanasia. CONCLUSIONS: Here, we report on the first successful rescue of recombinant HeV, including wild-type virus and viruses expressing two different reporter genes encoded as an additional gene cassette inserted between the P and M genes. We further demonstrate that the GFP virus retained the ability to cause fatal disease in a well-characterized ferret model of henipavirus infection despite the genome being an extra 1290 nucleotides in length.


Asunto(s)
Genes Reporteros , Virus Hendra/genética , Virus Hendra/patogenicidad , Infecciones por Henipavirus/virología , Animales , Línea Celular , Modelos Animales de Enfermedad , Hurones , Proteínas Fluorescentes Verdes/genética , Humanos , Luciferasas/genética , Masculino , Coloración y Etiquetado/métodos , Análisis de Supervivencia , Virulencia
13.
J Immunol ; 186(5): 3138-47, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21278349

RESUMEN

Bats are known to harbor a number of emerging and re-emerging zoonotic viruses, many of which are highly pathogenic in other mammals but result in no clinical symptoms in bats. The ability of bats to coexist with viruses may be the result of rapid control of viral replication early in the immune response. IFNs provide the first line of defense against viral infection in vertebrates. Type III IFNs (IFN-λs) are a recently identified IFN family that share similar antiviral activities with type I IFNs. To our knowledge, we demonstrate the first functional analysis of type III IFNs from any species of bat, with the investigation of two IFN-λ genes from the pteropid bat, Pteropus alecto. Our results demonstrate that bat type III IFN has similar antiviral activity to type I and III IFNs from other mammals. In addition, the two bat type III IFNs are differentially induced relative to each other and to type I IFNs after treatment or transfection with synthetic dsRNA. Infection with the bat paramyxovirus, Tioman virus, resulted in no upregulation of type I IFN production in bat splenocytes but was capable of inducing a type III IFN response in three of the four bats tested. To our knowledge, this is the first report to describe the simultaneous suppression of type I IFN and induction of type III IFN after virus infection. These results may have important implications for the role of type III IFNs in the ability of bats to coexist with viruses.


Asunto(s)
Quirópteros/inmunología , Quirópteros/virología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata , Interleucinas/biosíntesis , Interleucinas/genética , Animales , Antivirales/metabolismo , Antivirales/farmacología , Línea Celular , Línea Celular Transformada , Quirópteros/genética , Chlorocebus aethiops , Humanos , Interferón Tipo I/biosíntesis , Interferón Tipo I/metabolismo , Interferón Tipo I/fisiología , Interleucinas/fisiología , Ratones , Modelos Animales , Datos de Secuencia Molecular , Orthoreovirus de los Mamíferos/inmunología , Orthoreovirus de los Mamíferos/metabolismo , Infecciones por Paramyxoviridae/inmunología , Infecciones por Paramyxoviridae/metabolismo , Infecciones por Reoviridae/inmunología , Infecciones por Reoviridae/metabolismo , Células Vero
14.
Front Pharmacol ; 13: 813087, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35359837

RESUMEN

Coronavirus disease 2019 (COVID-19) caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an acute respiratory disease with systemic complications. Therapeutic strategies for COVID-19, including repurposing (partially) developed drugs are urgently needed, regardless of the increasingly successful vaccination outcomes. We characterized two-dimensional (2D) and three-dimensional models (3D) to establish a physiologically relevant airway epithelial model with potential for investigating SARS-CoV-2 therapeutics. Human airway basal epithelial cells maintained in submerged 2D culture were used at low passage to retain the capacity to differentiate into ciliated, club, and goblet cells in both air-liquid interface culture (ALI) and airway organoid cultures, which were then analyzed for cell phenotype makers. Airway biopsies from non-asthmatic and asthmatic donors enabled comparative evaluation of the level and distribution of immunoreactive angiotensin-converting enzyme 2 (ACE2). ACE2 and transmembrane serine proteinase 2 (TMPRSS2) mRNA were expressed in ALI and airway organoids at levels similar to those of native (i.e., non-cultured) human bronchial epithelial cells, whereas furin expression was more faithfully represented in ALI. ACE2 was mainly localized to ciliated and basal epithelial cells in human airway biopsies, ALI, and airway organoids. Cystic fibrosis appeared to have no influence on ACE2 gene expression. Neither asthma nor smoking status had consistent marked influence on the expression or distribution of ACE2 in airway biopsies. SARS-CoV-2 infection of ALI cultures did not increase the levels of selected cytokines. Organotypic, and particularly ALI airway cultures are useful and practical tools for investigation of SARS-CoV-2 infection and evaluating the clinical potential of therapeutics for COVID-19.

15.
Transbound Emerg Dis ; 69(5): e2366-e2377, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35491954

RESUMEN

Due to their geographical isolation and small populations, insular bats may not be able to maintain acute immunizing viruses that rely on a large population for viral maintenance. Instead, endemic transmission may rely on viruses establishing persistent infections within hosts or inducing only short-lived neutralizing immunity. Therefore, studies on insular populations are valuable for developing broader understanding of viral maintenance in bats. The Christmas Island flying-fox (CIFF; Pteropus natalis) is endemic on Christmas Island, a remote Australian territory, and is an ideal model species to understand viral maintenance in small, geographically isolated bat populations. Serum or plasma (n = 190), oral swabs (n = 199), faeces (n = 31), urine (n = 32) and urine swabs (n = 25) were collected from 228 CIFFs. Samples were tested using multiplex serological and molecular assays, and attempts at virus isolation to determine the presence of paramyxoviruses, betacoronaviruses and Australian bat lyssavirus. Analysis of serological data provides evidence that the species is maintaining a pararubulavirus and a betacoronavirus. There was little serological evidence supporting the presence of active circulation of the other viruses assessed in the present study. No viral nucleic acid was detected and no viruses were isolated. Age-seropositivity results support the hypothesis that geographically isolated bat populations can maintain some paramyxoviruses and coronaviruses. Further studies are required to elucidate infection dynamics and characterize viruses in the CIFF. Lastly, apparent absence of some pathogens could have implications for the conservation of the CIFF if a novel disease were introduced into the population through human carriage or an invasive species. Adopting increased biosecurity protocols for ships porting on Christmas Island and for researchers and bat carers working with flying-foxes are recommended to decrease the risk of pathogen introduction and contribute to the health and conservation of the species.


Asunto(s)
Quirópteros , Lyssavirus , Ácidos Nucleicos , Animales , Australia/epidemiología , Betacoronavirus , Humanos
16.
Sci Rep ; 12(1): 5680, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35383204

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the infectious disease COVID-19, which has rapidly become an international pandemic with significant impact on healthcare systems and the global economy. To assist antiviral therapy and vaccine development efforts, we performed a natural history/time course study of SARS-CoV-2 infection in ferrets to characterise and assess the suitability of this animal model. Ten ferrets of each sex were challenged intranasally with 4.64 × 104 TCID50 of SARS-CoV-2 isolate Australia/VIC01/2020 and monitored for clinical disease signs, viral shedding, and tissues collected post-mortem for histopathological and virological assessment at set intervals. We found that SARS-CoV-2 replicated in the upper respiratory tract of ferrets with consistent viral shedding in nasal wash samples and oral swab samples up until day 9. Infectious SARS-CoV-2 was recovered from nasal washes, oral swabs, nasal turbinates, pharynx, and olfactory bulb samples within 3-7 days post-challenge; however, only viral RNA was detected by qRT-PCR in samples collected from the trachea, lung, and parts of the gastrointestinal tract. Viral antigen was seen exclusively in nasal epithelium and associated sloughed cells and draining lymph nodes upon immunohistochemical staining. Due to the absence of clinical signs after viral challenge, our ferret model is appropriate for studying asymptomatic SARS-CoV-2 infections and most suitable for use in vaccine efficacy studies.


Asunto(s)
COVID-19 , Hurones , Animales , Mucosa Nasal , SARS-CoV-2 , Carga Viral
17.
Transbound Emerg Dis ; 69(2): 297-307, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33400387

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an emerging virus that has caused significant human morbidity and mortality since its detection in late 2019. With the rapid emergence has come an unprecedented programme of vaccine development with at least 300 candidates under development. Ferrets have proven to be an appropriate animal model for testing safety and efficacy of SARS-CoV-2 vaccines due to quantifiable virus shedding in nasal washes and oral swabs. Here, we outline our efforts early in the SARS-CoV-2 outbreak to propagate and characterize an Australian isolate of the virus in vitro and in an ex vivo model of human airway epithelium, as well as to demonstrate the susceptibility of domestic ferrets (Mustela putorius furo) to SARS-CoV-2 infection following intranasal challenge.


Asunto(s)
COVID-19 , Hurones , Animales , Australia , COVID-19/veterinaria , Vacunas contra la COVID-19 , Humanos , SARS-CoV-2
18.
NPJ Vaccines ; 6(1): 67, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33972565

RESUMEN

Vaccines against SARS-CoV-2 are likely to be critical in the management of the ongoing pandemic. A number of candidates are in Phase III human clinical trials, including ChAdOx1 nCoV-19 (AZD1222), a replication-deficient chimpanzee adenovirus-vectored vaccine candidate. In preclinical trials, the efficacy of ChAdOx1 nCoV-19 against SARS-CoV-2 challenge was evaluated in a ferret model of infection. Groups of ferrets received either prime-only or prime-boost administration of ChAdOx1 nCoV-19 via the intramuscular or intranasal route. All ChAdOx1 nCoV-19 administration combinations resulted in significant reductions in viral loads in nasal-wash and oral swab samples. No vaccine-associated adverse events were observed associated with the ChAdOx1 nCoV-19 candidate, with the data from this study suggesting it could be an effective and safe vaccine against COVID-19. Our study also indicates the potential for intranasal administration as a way to further improve the efficacy of this leading vaccine candidate.

19.
Emerg Infect Dis ; 16(11): 1767-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21029540

RESUMEN

Bat-to-horse transmission of Hendra virus has occurred at least 14 times. Although clinical signs in horses have differed, genome sequencing has demonstrated little variation among the isolates. Our sequencing of 5 isolates from recent Hendra virus outbreaks in horses found no correlation between sequences and time or geographic location of outbreaks.


Asunto(s)
Quirópteros , Genoma Viral , Virus Hendra/genética , Infecciones por Henipavirus/veterinaria , Enfermedades de los Caballos/virología , Animales , Australia/epidemiología , Brotes de Enfermedades/veterinaria , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/virología , Enfermedades de los Caballos/epidemiología , Caballos , Filogenia
20.
Viruses ; 12(11)2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33143230

RESUMEN

Bats are an important source of viral zoonoses, including paramyxoviruses. The paramyxoviral Pararubulavirus genus contains viruses mostly derived from bats that are common, diverse, distributed throughout the Old World, and known to be zoonotic. Here, we describe a new member of the genus Achimota pararubulavirus 3 (AchPV3) and its isolation from the urine of African straw-coloured fruit bats on primary bat kidneys cells. We sequenced and analysed the genome of AchPV3 relative to other Paramyxoviridae, revealing it to be similar to known pararubulaviruses. Phylogenetic analysis of AchPV3 revealed the failure of molecular detection in the urine sample from which AchPV3 was derived and an attachment protein most closely related with AchPV2-a pararubulavirus known to cause cross-species transmission. Together these findings add to the picture of pararubulaviruses, their sources, and variable zoonotic potential, which is key to our understanding of host restriction and spillover of bat-derived paramyxoviruses. AchPV3 represents a novel candidate zoonosis and an important tool for further study.


Asunto(s)
Quirópteros/virología , Infecciones por Paramyxoviridae/veterinaria , Paramyxovirinae/clasificación , Filogenia , Animales , Células Cultivadas , Chlorocebus aethiops , Genoma Viral , Riñón/citología , Riñón/virología , Infecciones por Paramyxoviridae/orina , Paramyxovirinae/aislamiento & purificación , ARN Viral , Células Vero , Secuenciación Completa del Genoma , Zoonosis/virología
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