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1.
Transbound Emerg Dis ; 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34890118

RESUMO

Rift Valley fever virus (RVFV) is a mosquito-borne pathogen with significant human and veterinary health consequences that periodically emerges in epizootics. RVFV causes fetal loss and death in ruminants and in humans can lead to liver and renal disease, delayed-onset encephalitis, retinitis, and in some cases severe hemorrhagic fever. A live attenuated vaccine candidate (DDVax), was developed by the deletion of the virulence factors NSs and NSm from a clinical isolate, ZH501, and has proven safe and immunogenic in rodents, pregnant sheep and non-human primates. Deletion of NSm also severely restricted mosquito midgut infection and inhibited vector-borne transmission. To demonstrate environmental safety, this study investigated the replication, dissemination and transmission efficiency of DDVax in mosquitoes following oral exposure compared to RVFV strains MP-12 and ZH501. Infection and dissemination profiles were also measured in mosquitoes 7 days after they fed on goats inoculated with DDvax or MP-12. We hypothesized that DDVax would infect mosquitoes at significantly lower rates than other RVFV strains and, due to lack of NSm, be transmission incompetent. Exposure of Ae. aegypti and Cx. tarsalis to 8 log10 plaque forming units (PFU)/mL DDVax by artificial bloodmeal resulted in significantly reduced DDVax infection rates in mosquito bodies compared to controls. Plaque assays indicated negligible transmission of infectious DDVax in Cx. tarsalis saliva (1/140 sampled) and none in Ae aegypti saliva (0/120). Serum from goats inoculated with DDVax or MP-12 did not harbor detectable infectious virus by plaque assay at 1, 2, or 3 days-post-inoculation. Infectious virus was, however, recovered from Aedes and Culex bodies that fed on goats vaccinated with MP-12 (13.8% and 4.6%, respectively), but strikingly, DDvax positive mosquito bodies were greatly reduced (4%, and 0%, respectively). Furthermore, DDVax did not disseminate to legs/wings in any of the goat-fed mosquitoes. Collectively, these results are consistent with a beneficial environmental safety profile. This article is protected by copyright. All rights reserved.

2.
Microbiol Resour Announc ; 10(26): e0132120, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34197198

RESUMO

Eight isolates of Streptococcus equi subsp. zooepidemicus were isolated from mares with clinical cases of endometritis. S. equi subsp. zooepidemicus strains were chosen for sequencing based on differing levels of biofilm production in vitro. Using Illumina short-read sequencing in conjunction with MinION sequencing, we report the genomes of eight isolates.

3.
J Gen Virol ; 102(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34227935

RESUMO

Members of the family Bornaviridae produce enveloped virions containing a linear negative-sense non-segmented RNA genome of about 9 kb. Bornaviruses are found in mammals, birds, reptiles and fish. The most-studied viruses with public health and veterinary impact are Borna disease virus 1 and variegated squirrel bornavirus 1, both of which cause fatal encephalitis in humans. Several orthobornaviruses cause neurological and intestinal disorders in birds, mostly parrots. Endogenous bornavirus-like sequences occur in the genomes of various animals. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Bornaviridae, which is available at ictv.global/report/bornaviridae.


Assuntos
Vírus da Doença de Borna/classificação , Bornaviridae/classificação , Animais , Doença de Borna/virologia , Vírus da Doença de Borna/genética , Vírus da Doença de Borna/fisiologia , Vírus da Doença de Borna/ultraestrutura , Bornaviridae/genética , Bornaviridae/fisiologia , Bornaviridae/ultraestrutura , Genoma Viral , Especificidade de Hospedeiro , Humanos , Vírion/ultraestrutura , Replicação Viral
4.
Vaccines (Basel) ; 9(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916180

RESUMO

The COVID-19 pandemic has generated intense interest in the rapid development and evaluation of vaccine candidates for this disease and other emerging diseases. Several novel methods for preparing vaccine candidates are currently undergoing clinical evaluation in response to the urgent need to prevent the spread of COVID-19. In many cases, these methods rely on new approaches for vaccine production and immune stimulation. We report on the use of a novel method (SolaVAX) for production of an inactivated vaccine candidate and the testing of that candidate in a hamster animal model for its ability to prevent infection upon challenge with SARS-CoV-2 virus. The studies employed in this work included an evaluation of the levels of neutralizing antibody produced post-vaccination, levels of specific antibody sub-types to RBD and spike protein that were generated, evaluation of viral shedding post-challenge, flow cytometric and single cell sequencing data on cellular fractions and histopathological evaluation of tissues post-challenge. The results from this preliminary evaluation provide insight into the immunological responses occurring as a result of vaccination with the proposed vaccine candidate and the impact that adjuvant formulations, specifically developed to promote Th1 type immune responses, have on vaccine efficacy and protection against infection following challenge with live SARS-CoV-2. This data may have utility in the development of effective vaccine candidates broadly. Furthermore, the results of this preliminary evaluation suggest that preparation of a whole virion vaccine for COVID-19 using this specific photochemical method may have potential utility in the preparation of one such vaccine candidate.

5.
PLoS Pathog ; 17(3): e1009315, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33647063

RESUMO

Bunyaviruses (Negarnaviricota: Bunyavirales) are a large and diverse group of viruses that include important human, veterinary, and plant pathogens. The rapid characterization of known and new emerging pathogens depends on the availability of comprehensive reference sequence databases that can be used to match unknowns, infer evolutionary relationships and pathogenic potential, and make response decisions in an evidence-based manner. In this study, we determined the coding-complete genome sequences of 99 bunyaviruses in the Centers for Disease Control and Prevention's Arbovirus Reference Collection, focusing on orthonairoviruses (family Nairoviridae), orthobunyaviruses (Peribunyaviridae), and phleboviruses (Phenuiviridae) that either completely or partially lacked genome sequences. These viruses had been collected over 66 years from 27 countries from vertebrates and arthropods representing 37 genera. Many of the viruses had been characterized serologically and through experimental infection of animals but were isolated in the pre-sequencing era. We took advantage of our unusually large sample size to systematically evaluate genomic characteristics of these viruses, including reassortment, and co-infection. We corroborated our findings using several independent molecular and virologic approaches, including Sanger sequencing of 197 genome segments, and plaque isolation of viruses from putative co-infected virus stocks. This study contributes to the described genetic diversity of bunyaviruses and will enhance the capacity to characterize emerging human pathogenic bunyaviruses.


Assuntos
Genoma Viral/genética , Nairovirus/genética , Orthobunyavirus/genética , Vírus de RNA/genética , Animais , Arbovírus/genética , Artrópodes/genética , Sequência de Bases , Humanos , Filogenia
6.
Viruses ; 12(11)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33228135

RESUMO

Serpentoviruses are an emerging group of nidoviruses known to cause respiratory disease in snakes and have been associated with disease in other non-avian reptile species (lizards and turtles). This study describes multiple episodes of respiratory disease-associated mortalities in a collection of juvenile veiled chameleons (Chamaeleo calyptratus). Histopathologic lesions included rhinitis and interstitial pneumonia with epithelial proliferation and abundant mucus. Metagenomic sequencing detected coinfection with two novel serpentoviruses and a novel orthoreovirus. Veiled chameleon serpentoviruses are most closely related to serpentoviruses identified in snakes, lizards, and turtles (approximately 40-50% nucleotide and amino acid identity of ORF1b). Veiled chameleon orthoreovirus is most closely related to reptilian orthoreoviruses identified in snakes (approximately 80-90% nucleotide and amino acid identity of the RNA-dependent RNA polymerase). A high prevalence of serpentovirus infection (>80%) was found in clinically healthy subadult and adult veiled chameleons, suggesting the potential for chronic subclinical carriers. Juvenile veiled chameleons typically exhibited a more rapid progression compared to subadults and adults, indicating a possible age association with morbidity and mortality. This is the first description of a serpentovirus infection in any chameleon species. A causal relationship between serpentovirus infection and respiratory disease in chameleons is suspected. The significance of orthoreovirus coinfection remains unknown.


Assuntos
Coinfecção/veterinária , Lagartos/virologia , Doenças Pulmonares Intersticiais/veterinária , Nidovirales/patogenicidade , Orthoreovirus/patogenicidade , Infecções por Reoviridae/veterinária , Animais , Animais de Zoológico/virologia , Coinfecção/virologia , Surtos de Doenças/veterinária , Feminino , Doenças Pulmonares Intersticiais/virologia , Masculino , Metagenômica , Nidovirales/genética , Orthoreovirus/genética , Prevalência
7.
Viruses ; 12(9)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32961886

RESUMO

Bluetongue virus (BTV) is an arbovirus that has been associated with dramatic epizootics in both wild and domestic ruminants in recent decades. As a segmented, double-stranded RNA virus, BTV can evolve via several mechanisms due to its genomic structure. However, the effect of BTV's alternating-host transmission cycle on the virus's genetic diversification remains poorly understood. Whole genome sequencing approaches offer a platform for investigating the effect of host-alternation across all ten segments of BTV's genome. To understand the role of alternating hosts in BTV's genetic diversification, a field isolate was passaged under three different conditions: (i) serial passages in Culicoides sonorensis cells, (ii) serial passages in bovine pulmonary artery endothelial cells, or (iii) alternating passages between insect and bovine cells. Aliquots of virus were sequenced, and single nucleotide variants were identified. Measures of viral population genetics were used to quantify the genetic diversification that occurred. Two consensus variants in segments 5 and 10 occurred in virus from all three conditions. While variants arose across all passages, measures of genetic diversity remained largely similar across cell culture conditions. Despite passage in a relaxed in vitro system, we found that this BTV isolate exhibited genetic stability across passages and conditions. Our findings underscore the valuable role that whole genome sequencing may play in improving understanding of viral evolution and highlight the genetic stability of BTV.


Assuntos
Vírus Bluetongue/genética , Bluetongue/transmissão , Bluetongue/virologia , Animais , Vírus Bluetongue/fisiologia , Bovinos , Ceratopogonidae/virologia , Células Endoteliais/virologia , Variação Genética , Peptídeo Hidrolases , Inoculações Seriadas , Proteínas Virais/genética , Replicação Viral
8.
J Virol ; 94(20)2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32759315

RESUMO

Partitiviruses are segmented, multipartite double-stranded RNA (dsRNA) viruses that until recently were only known to infect fungi, plants, and protozoans. Metagenomic surveys have revealed that partitivirus-like sequences are also commonly associated with arthropods. One arthropod-associated partitivirus, galbut virus, is common in wild populations of Drosophila melanogaster To begin to understand the processes that underlie this virus's high global prevalence, we established colonies of wild-caught infected flies. Infection remained at stably high levels over 3 years, with between 63 and 100% of individual flies infected. Galbut virus infects fly cells and replicates in tissues throughout infected adults, including reproductive tissues and the gut epithelium. We detected no evidence of horizontal transmission via ingestion, but vertical transmission from either infected females or infected males was ∼100% efficient. Vertical transmission of a related partitivirus, verdadero virus, that we discovered in a laboratory colony of Aedes aegypti mosquitoes was similarly efficient. This suggests that efficient biparental vertical transmission may be a feature of at least a subset of insect-infecting partitiviruses. To study the impact of galbut virus infection free from the confounding effect of other viruses, we generated an inbred line of flies with galbut virus as the only detectable virus infection. We were able to transmit infection experimentally via microinjection of homogenate from these galbut-only flies. This sets the stage for experiments to understand the biological impact and possible utility of partitiviruses infecting model organisms and disease vectors.IMPORTANCE Galbut virus is a recently discovered partitivirus that is extraordinarily common in wild populations of the model organism Drosophila melanogaster Like for most viruses discovered through metagenomics, most of the basic biological questions about this virus remain unanswered. We found that galbut virus, along with a closely related partitivirus found in Aedes aegypti mosquitoes, is transmitted from infected females or males to offspring with ∼100% efficiency and can be maintained in laboratory colonies over years. This efficient transmission mechanism likely underlies the successful spread of these viruses through insect populations. We created Drosophila lines that contained galbut virus as the only virus infection and showed that these flies can be used as a source for experimental infections. This provides insight into how arthropod-infecting partitiviruses may be maintained in nature and sets the stage for exploration of their biology and potential utility.


Assuntos
Aedes/virologia , Vírus de RNA de Cadeia Dupla/metabolismo , Animais , Drosophila melanogaster , Feminino , Masculino
9.
Viruses ; 12(6)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32498297

RESUMO

As part of research and wildlife disease surveillance efforts, we performed necropsy examinations of 125 free-ranging (n = 114) and captive (n = 11) prairie dogs in Colorado from 2009 to 2017. From these cases, we identified three cases of thymic lymphoma in free-ranging Gunnison's prairie dogs (Cynomys gunnisoni), and we identified a novel retroviral sequence associated with these tumors. The viral sequence is 7700 nucleotides in length and exhibits a genetic organization that is consistent with the characteristics of a type D betaretrovirus. The proposed name of this virus is Gunnison's prairie dog retrovirus (GPDRV). We screened all 125 prairie dogs for the presence of GPDRV using PCR with envelope-specific primers and DNA extracted from spleen samples. Samples were from Gunnison's prairie dogs (n = 59), black-tailed prairie dogs (Cynomys ludovicianus) (n = 40), and white-tailed prairie dogs (Cynomys leucurus) (n = 26). We identified GPDRV in a total of 7/125 (5.6%) samples including all three of the prairie dogs with thymic lymphoma, as well as spleen from an additional four Gunnison's prairie dogs with no tumors recognized at necropsy. None of the GPDRV-negative Gunnison's prairie dogs had thymic lymphomas. We also identified a related, apparently endogenous retroviral sequence in all prairie dog samples. These results suggest that GPDRV infection may lead to development of thymic lymphoma in Gunnison's prairie dogs.


Assuntos
Linfoma/veterinária , Retroviridae/isolamento & purificação , Doenças dos Roedores/virologia , Timoma/veterinária , Sequência de Aminoácidos , Animais , Animais Selvagens/virologia , Colorado , Feminino , Genoma Viral , Linfoma/patologia , Linfoma/virologia , Filogenia , Retroviridae/química , Retroviridae/classificação , Retroviridae/genética , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/patologia , Sciuridae/classificação , Sciuridae/virologia , Alinhamento de Sequência , Timoma/patologia , Timoma/virologia , Proteínas Virais/química , Proteínas Virais/genética
10.
Int J Mol Sci ; 21(7)2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32268593

RESUMO

LIN28 inhibits let-7 miRNA maturation which prevents cell differentiation and promotes proliferation. We hypothesized that the LIN28-let-7 axis regulates proliferation-associated genes in sheep trophectoderm in vivo. Day 9-hatched sheep blastocysts were incubated with lentiviral particles to deliver shRNA targeting LIN28 specifically to trophectoderm cells. At day 16, conceptus elongation was significantly reduced in LIN28A and LIN28B knockdowns. Let-7 miRNAs were significantly increased and IGF2BP1-3, HMGA1, ARID3B, and c-MYC were decreased in trophectoderm from knockdown conceptuses. Ovine trophoblast (OTR) cells derived from day 16 trophectoderm are a useful tool for in vitro experiments. Surprisingly, LIN28 was significantly reduced and let-7 miRNAs increased after only a few passages of OTR cells, suggesting these passaged cells represent a more differentiated phenotype. To create an OTR cell line more similar to day 16 trophectoderm we overexpressed LIN28A and LIN28B, which significantly decreased let-7 miRNAs and increased IGF2BP1-3, HMGA1, ARID3B, and c-MYC compared to control. This is the first study showing the role of the LIN28-let-7 axis in trophoblast proliferation and conceptus elongation in vivo. These results suggest that reduced LIN28 during early placental development can lead to reduced trophoblast proliferation and sheep conceptus elongation at a critical period for successful establishment of pregnancy.


Assuntos
Ectoderma/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Ligação a RNA/genética , Trofoblastos/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Feminino , Placenta , Gravidez , Proteínas de Ligação a RNA/metabolismo , Ovinos
11.
Front Vet Sci ; 6: 338, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632990

RESUMO

The aim of this study of serpentovirus infection in captive snakes was to assess the susceptibility of different types of snakes to infection and disease, to survey viral genetic diversity, and to evaluate management practices that may limit infection and disease. Antemortem oral swabs were collected from 639 snakes from 12 US collections, including 62 species, 28 genera, and 6 families: Pythonidae (N = 414 snakes; pythons were overrepresented in the sample population), Boidae (79), Colubridae (116), Lamprophiidae (4), Elapidae (12), and Viperidae (14). Infection was more common in pythons (38%; 95% CI: 33.1-42.4%), and in boas (10%; 95% CI: 5.2-18.7%) than in colubrids (0.9%, 95% CI: <0.01-4.7%); infection was not detected in other snake families (lamprophiids 0/4, 95% CI: 0-49%; elapids 0/12, 95% CI: 0-24.2%; and vipers 0/14, 95% CI: 0-21.5%), but more of these snakes need to be tested to confirm these findings. Clinical signs of respiratory disease were common in infected pythons (85 of 144). Respiratory signs were only observed in 1 of 8 infected boas and were absent in the single infected colubrid. Divergent serpentoviruses were detected in pythons, boas, and colubrids, suggesting that different serpentoviruses might vary in their ability to infect snakes of different families. Older snakes were more likely to be infected than younger snakes (p-value < 0.001) but males and females were equally likely to be infected (female prevalence: 23.4%, 95% CI 18.7-28.9%; male prevalence: 23.5%, 95% CI 18-30.1%; p-value = 0.144). Neither age (p-value = 0.32) nor sex (p-value = 0.06) was statistically associated with disease severity. Longitudinal sampling of pythons in a single collection over 28 months revealed serpentovirus infection is persistent, and viral clearance was not observed. In this collection, infection was associated with significantly increased rates of mortality (p-value = 0.001) with death of 75% of infected pythons and no uninfected pythons over this period. Offspring of infected parents were followed: vertical transmission either does not occur or occurs with a much lower efficiency than horizontal transmission. Overall, these findings confirm that serpentoviruses pose a significant threat to the health of captive python populations and can cause infection in boa and colubrid species.

12.
Viruses ; 11(10)2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615058

RESUMO

RNA viruses are a major source of emerging and re-emerging infectious diseases around the world. We developed a method to identify RNA viruses that is based on the fact that RNA viruses produce double-stranded RNA (dsRNA) while replicating. Purifying and sequencing dsRNA from the total RNA isolated from infected tissue allowed us to recover dsRNA virus sequences and replicated sequences from single-stranded RNA (ssRNA) viruses. We refer to this approach as dsRNA-Seq. By assembling dsRNA sequences into contigs we identified full length or partial RNA viral genomes of varying genome types infecting mammalian culture samples, identified a known viral disease agent in laboratory infected mice, and successfully detected naturally occurring RNA viral infections in reptiles. Here, we show that dsRNA-Seq is a preferable method for identifying viruses in organisms that don't have sequenced genomes and/or commercially available rRNA depletion reagents. In addition, a significant advantage of this method is the ability to identify replicated viral sequences of ssRNA viruses, which is useful for distinguishing infectious viral agents from potential noninfectious viral particles or contaminants.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Infecções por Vírus de RNA/virologia , Vírus de RNA/genética , RNA de Cadeia Dupla/isolamento & purificação , Animais , Chlorocebus aethiops , Genoma Viral , Camundongos , Vírus de RNA/isolamento & purificação , RNA Viral/isolamento & purificação , RNA-Seq , Células Vero , Vírion , Replicação Viral
13.
J Gen Virol ; 100(8): 1200-1201, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31192784

RESUMO

Members of the family Arenaviridae produce enveloped virions containing genomes consisting of two or three single-stranded RNA segments totalling about 10.5 kb. Arenaviruses can infect mammals, including humans and other primates, snakes, and fish. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Arenaviridae, which is available at www.ictv.global/report/arenaviridae.


Assuntos
Infecções por Arenaviridae/veterinária , Infecções por Arenaviridae/virologia , Arenaviridae/classificação , Arenaviridae/genética , Animais , Arenaviridae/isolamento & purificação , Arenaviridae/ultraestrutura , Peixes , Genoma Viral , Humanos , Filogenia , RNA Viral/genética , Répteis , Proteínas Virais/genética
14.
J Hered ; 110(3): 261-274, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067326

RESUMO

The outbreak and transmission of disease-causing pathogens are contributing to the unprecedented rate of biodiversity decline. Recent advances in genomics have coalesced into powerful tools to monitor, detect, and reconstruct the role of pathogens impacting wildlife populations. Wildlife researchers are thus uniquely positioned to merge ecological and evolutionary studies with genomic technologies to exploit unprecedented "Big Data" tools in disease research; however, many researchers lack the training and expertise required to use these computationally intensive methodologies. To address this disparity, the inaugural "Genomics of Disease in Wildlife" workshop assembled early to mid-career professionals with expertise across scientific disciplines (e.g., genomics, wildlife biology, veterinary sciences, and conservation management) for training in the application of genomic tools to wildlife disease research. A horizon scanning-like exercise, an activity to identify forthcoming trends and challenges, performed by the workshop participants identified and discussed 5 themes considered to be the most pressing to the application of genomics in wildlife disease research: 1) "Improving communication," 2) "Methodological and analytical advancements," 3) "Translation into practice," 4) "Integrating landscape ecology and genomics," and 5) "Emerging new questions." Wide-ranging solutions from the horizon scan were international in scope, itemized both deficiencies and strengths in wildlife genomic initiatives, promoted the use of genomic technologies to unite wildlife and human disease research, and advocated best practices for optimal use of genomic tools in wildlife disease projects. The results offer a glimpse of the potential revolution in human and wildlife disease research possible through multi-disciplinary collaborations at local, regional, and global scales.


Assuntos
Doenças dos Animais/etiologia , Animais Selvagens , Genômica , Pesquisa , Doenças dos Animais/epidemiologia , Doenças dos Animais/transmissão , Animais , Biodiversidade , Evolução Biológica , Biologia Computacional/métodos , Suscetibilidade a Doenças , Ecologia , Meio Ambiente , Genoma , Genômica/métodos , Interações Hospedeiro-Patógeno/genética , Humanos
15.
Virology ; 528: 181-197, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30616207

RESUMO

Identifying novel viruses or assessing viral variation by NGS requires high sequencing coverage. More than 90% of total RNA is ribosomal (rRNA), making variant calling, virus discovery or transcriptomic profiling difficult. Current methods to increase informative reads suffer from drawbacks, either they cannot be used for some viruses, are optimized for a single species, or introduce bias. We describe a two-part approach combining reverse-transcription to create RNA/DNA hybrids which are then degraded with RNaseH/DNase sequentially that works for three medically relevant mosquito genera; Aedes, Anopheles, and Culex. We demonstrate depletion of rRNA from different samples, including whole mosquitoes and midgut contents from FTA cards. We describe novel insect-specific virus genomes from field collected mosquitoes. The protocol requires only common laboratory reagents and small oligonucleotides specific to rRNA. This approach can be adapted for other organisms, aiding virus diversity analyses, virus discovery and transcriptomics in both laboratory and field samples.


Assuntos
Culicidae/virologia , RNA Ribossômico/genética , Transcrição Reversa , Ribonuclease H/metabolismo , Vírus do Nilo Ocidental/patogenicidade , Aedes/virologia , Animais , Anopheles/virologia , Culex/virologia , Culicidae/genética , Flaviviridae/classificação , Flaviviridae/isolamento & purificação , Perfilação da Expressão Gênica , Genoma Viral , Interações entre Hospedeiro e Microrganismos/genética , Ribonuclease H/genética , Transcriptoma
16.
Syst Biol ; 68(5): 828-839, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597118

RESUMO

The International Committee on Taxonomy of Viruses (ICTV) is tasked with classifying viruses into taxa (phyla to species) and devising taxon names. Virus names and virus name abbreviations are currently not within the ICTV's official remit and are not regulated by an official entity. Many scientists, medical/veterinary professionals, and regulatory agencies do not address evolutionary questions nor are they concerned with the hierarchical organization of the viral world, and therefore, have limited use for ICTV-devised taxa. Instead, these professionals look to the ICTV as an expert point source that provides the most current taxonomic affiliations of viruses of interests to facilitate document writing. These needs are currently unmet as an ICTV-supported, easily searchable database that includes all published virus names and abbreviations linked to their taxa is not available. In addition, in stark contrast to other biological taxonomic frameworks, virus taxonomy currently permits individual species to have several members. Consequently, confusion emerges among those who are not aware of the difference between taxa and viruses, and because certain well-known viruses cannot be located in ICTV publications or be linked to their species. In addition, the number of duplicate names and abbreviations has increased dramatically in the literature. To solve this conundrum, the ICTV could mandate listing all viruses of established species and all reported unclassified viruses in forthcoming online ICTV Reports and create a searchable webpage using this information. The International Union of Microbiology Societies could also consider changing the mandate of the ICTV to include the nomenclature of all viruses in addition to taxon considerations. With such a mandate expansion, official virus names and virus name abbreviations could be catalogued and virus nomenclature could be standardized. As a result, the ICTV would become an even more useful resource for all stakeholders in virology.


Assuntos
Classificação/métodos , Virologia/métodos , Vírus/classificação , Cooperação Internacional , Virologia/normas , Virologia/tendências
17.
Virus Evol ; 4(2): vey034, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30524754

RESUMO

Ebola virus (EBOV) disease is a viral hemorrhagic fever with a high case-fatality rate in humans. This disease is caused by four members of the filoviral genus Ebolavirus, including EBOV. The natural hosts reservoirs of ebolaviruses remain to be identified. Glycoprotein 2 of reptarenaviruses, known to infect only boa constrictors and pythons, is similar in sequence and structure to ebolaviral glycoprotein 2, suggesting that EBOV may be able to infect reptilian cells. Therefore, we serially passaged EBOV and a distantly related filovirus, Marburg virus (MARV), in boa constrictor JK cells and characterized viral infection/replication and mutational frequency by confocal imaging and sequencing. We observed that EBOV efficiently infected and replicated in JK cells, but MARV did not. In contrast to most cell lines, EBOV-infected JK cells did not result in an obvious cytopathic effect. Surprisingly, genomic characterization of serial-passaged EBOV in JK cells revealed that genomic adaptation was not required for infection. Deep sequencing coverage (>10,000×) demonstrated the existence of only a single nonsynonymous variant (EBOV glycoprotein precursor pre-GP T544I) of unknown significance within the viral population that exhibited a shift in frequency of at least 10 per cent over six serial passages. In summary, we present the first reptilian cell line that replicates a filovirus at high titers, and for the first time demonstrate a filovirus genus-specific restriction to MARV in a cell line. Our data suggest the possibility that there may be differences between the natural host spectra of ebolaviruses and marburgviruses.

18.
Viruses ; 10(7)2018 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-30037148

RESUMO

Ixodes scapularis ticks harbor a variety of microorganisms, including eukaryotes, bacteria and viruses. Some of these can be transmitted to and cause disease in humans and other vertebrates. Others are not pathogenic, but may impact the ability of the tick to harbor and transmit pathogens. A growing number of studies have examined the influence of bacteria on tick vector competence but the influence of the tick virome remains less clear, despite a surge in the discovery of tick-associated viruses. In this study, we performed shotgun RNA sequencing on 112 individual adult I. scapularis collected in Wisconsin, USA. We characterized the abundance, prevalence and co-infection rates of viruses, bacteria and eukaryotic microorganisms. We identified pairs of tick-infecting microorganisms whose observed co-infection rates were higher or lower than would be expected, or whose RNA levels were positively correlated in co-infected ticks. Many of these co-occurrence and correlation relationships involved two bunyaviruses, South Bay virus and blacklegged tick phlebovirus-1. These viruses were also the most prevalent microorganisms in the ticks we sampled, and had the highest average RNA levels. Evidence of associations between microbes included a positive correlation between RNA levels of South Bay virus and Borrelia burgdorferi, the Lyme disease agent. These findings contribute to the rationale for experimental studies on the impact of viruses on tick biology and vector competence.


Assuntos
Coinfecção/microbiologia , Coinfecção/virologia , Ixodes/microbiologia , Ixodes/virologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Borrelia burgdorferi/genética , Borrelia burgdorferi/isolamento & purificação , Coinfecção/epidemiologia , Eucariotos/genética , Eucariotos/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Ixodes/genética , Doença de Lyme , Microbiota/genética , Orthobunyavirus/genética , Orthobunyavirus/isolamento & purificação , Phlebovirus/genética , Phlebovirus/isolamento & purificação , Prevalência , Simbiose , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/microbiologia , Infestações por Carrapato/virologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/virologia , Vírus/genética , Vírus/isolamento & purificação , Wisconsin/epidemiologia
19.
Virology ; 521: 175-180, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29957338

RESUMO

Mosquito cell lines have been used extensively in research to isolate and propagate arthropod-borne viruses and understand virus-vector interactions. Despite their utility as an in vitro tool, these cell lines are poorly defined and may harbor insect-specific viruses. Accordingly, we screened four commonly-used mosquito cell lines, C6/36 and U4.4 cells from Aedes albopictus, Aag2 cells from Aedes aegypti, and Hsu cells from Culex quinquefasciatus, for the presence of adventitious (i.e. exogenous) viruses. All four cell lines stained positive for double-stranded RNA, indicative of RNA virus replication. We subsequently identified viruses infecting Aag2, U4.4 and Hsu cell lines using untargeted next-generation sequencing, but not C6/36 cells. PCR confirmation revealed that these sequences stem from active viral replication and/or integration into the cellular genome. Our results show that these commonly-used mosquito cell lines are persistently-infected with several viruses. This finding may be critical to interpreting data generated in these systems.


Assuntos
Vírus de RNA/crescimento & desenvolvimento , Vírus de RNA/isolamento & purificação , Replicação Viral , Aedes , Animais , Linhagem Celular , Culex , Sequenciamento de Nucleotídeos em Larga Escala , Reação em Cadeia da Polimerase , Vírus de RNA/genética , RNA de Cadeia Dupla/análise , RNA de Cadeia Dupla/genética , Análise de Sequência de RNA , Coloração e Rotulagem
20.
PLoS Negl Trop Dis ; 12(3): e0006348, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29561834

RESUMO

BACKGROUND: Novel surveillance strategies are needed to detect the rapid and continuous emergence of infectious disease agents. Ideally, new sampling strategies should be simple to implement, technologically uncomplicated, and applicable to areas where emergence events are known to occur. To this end, xenosurveillance is a technique that makes use of blood collected by hematophagous arthropods to monitor and identify vertebrate pathogens. Mosquitoes are largely ubiquitous animals that often exist in sizable populations. As well, many domestic or peridomestic species of mosquitoes will preferentially take blood-meals from humans, making them a unique and largely untapped reservoir to collect human blood. METHODOLOGY/PRINCIPAL FINDINGS: We sought to take advantage of this phenomenon by systematically collecting blood-fed mosquitoes during a field trail in Northern Liberia to determine whether pathogen sequences from blood engorged mosquitoes accurately mirror those obtained directly from humans. Specifically, blood was collected from humans via finger-stick and by aspirating bloodfed mosquitoes from the inside of houses. Shotgun metagenomic sequencing of RNA and DNA derived from these specimens was performed to detect pathogen sequences. Samples obtained from xenosurveillance and from finger-stick blood collection produced a similar number and quality of reads aligning to two human viruses, GB virus C and hepatitis B virus. CONCLUSIONS/SIGNIFICANCE: This study represents the first systematic comparison between xenosurveillance and more traditional sampling methodologies, while also demonstrating the viability of xenosurveillance as a tool to sample human blood for circulating pathogens.


Assuntos
Culicidae/virologia , Monitoramento Epidemiológico , Viroses/epidemiologia , Vírus/isolamento & purificação , Animais , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite B/epidemiologia , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/patogenicidade , Hepatite C/epidemiologia , Hepatite C/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Libéria/epidemiologia , Metagenômica , Mosquitos Vetores/virologia , Amostragem , Viroses/virologia , Vírus/genética , Vírus/patogenicidade
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