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1.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38836701

RESUMO

Biomedical data are generated and collected from various sources, including medical imaging, laboratory tests and genome sequencing. Sharing these data for research can help address unmet health needs, contribute to scientific breakthroughs, accelerate the development of more effective treatments and inform public health policy. Due to the potential sensitivity of such data, however, privacy concerns have led to policies that restrict data sharing. In addition, sharing sensitive data requires a secure and robust infrastructure with appropriate storage solutions. Here, we examine and compare the centralized and federated data sharing models through the prism of five large-scale and real-world use cases of strategic significance within the European data sharing landscape: the French Health Data Hub, the BBMRI-ERIC Colorectal Cancer Cohort, the federated European Genome-phenome Archive, the Observational Medical Outcomes Partnership/OHDSI network and the EBRAINS Medical Informatics Platform. Our analysis indicates that centralized models facilitate data linkage, harmonization and interoperability, while federated models facilitate scaling up and legal compliance, as the data typically reside on the data generator's premises, allowing for better control of how data are shared. This comparative study thus offers guidance on the selection of the most appropriate sharing strategy for sensitive datasets and provides key insights for informed decision-making in data sharing efforts.


Assuntos
Disciplinas das Ciências Biológicas , Disseminação de Informação , Humanos , Informática Médica/métodos
2.
Emerg Infect Dis ; 29(1): 20-25, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36573519

RESUMO

Seoul orthohantavirus (SEOV) is not considered a major public health threat on the continent of Africa. However, Africa is exposed to rodentborne SEOV introduction events through maritime traffic after exponential growth of trade with the rest of the world. Serologic studies have already detected hantavirus antibodies in human populations, and recent investigations have confirmed circulation of hantavirus, including SEOV, in rat populations. Thus, SEOV is a possible emerging zoonotic risk in Africa. Moreover, the range of SEOV could rapidly expand, and transmission to humans could increase because of host switching from the usual brown rat (Rattus norvegicus) species, which is currently invading Africa, to the more widely installed black rat (R. rattus) species. Because of rapid economic development, environmental and climatic changes, and increased international trade, strengthened surveillance is urgently needed to prevent SEOV dissemination among humans in Africa.


Assuntos
Infecções por Hantavirus , Febre Hemorrágica com Síndrome Renal , Orthohantavírus , Vírus Seoul , Animais , Ratos , Humanos , Comércio , Seul , Internacionalidade , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/veterinária
3.
PLoS One ; 16(5): e0251263, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34010292

RESUMO

Rift Valley fever virus (RVFV), an arbovirus belonging to the Phlebovirus genus of the Phenuiviridae family, causes the zoonotic and mosquito-borne RVF. The virus, which primarily affects livestock (ruminants and camels) and humans, is at the origin of recent major outbreaks across the African continent (Mauritania, Libya, Sudan), and in the South-Western Indian Ocean (SWIO) islands (Mayotte). In order to be better prepared for upcoming outbreaks, to predict its introduction in RVFV unscathed countries, and to run efficient surveillance programmes, the priority is harmonising and improving the diagnostic capacity of endemic countries and/or countries considered to be at risk of RVF. A serological inter-laboratory proficiency test (PT) was implemented to assess the capacity of veterinary laboratories to detect antibodies against RVFV. A total of 18 laboratories in 13 countries in the Middle East, North Africa, South Africa, and the Indian Ocean participated in the initiative. Two commercial kits and two in-house serological assays for the detection of RVFV specific IgG antibodies were tested. Sixteen of the 18 participating laboratories (88.9%) used commercial kits, the analytical performance of test sensitivity and specificity based on the seroneutralisation test considered as the reference was 100%. The results obtained by the laboratories which used the in-house assay were correct in only one of the two criteria (either sensitivity or specificity). In conclusion, most of the laboratories performed well in detecting RVFV specific IgG antibodies and can therefore be considered to be prepared. Three laboratories in three countries need to improve their detection capacities. Our study demonstrates the importance of conducting regular proficiency tests to evaluate the level of preparedness of countries and of building a network of competent laboratories in terms of laboratory diagnosis to better face future emerging diseases in emergency conditions.


Assuntos
Febre do Vale de Rift/diagnóstico , África/epidemiologia , Animais , Anticorpos Antivirais/sangue , Doenças Endêmicas/veterinária , Ensaio de Imunoadsorção Enzimática/normas , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Imunoglobulina G/sangue , Oceano Índico/epidemiologia , Laboratórios/normas , Oriente Médio/epidemiologia , Garantia da Qualidade dos Cuidados de Saúde , Reprodutibilidade dos Testes , Febre do Vale de Rift/epidemiologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Fatores de Risco , Testes Sorológicos/normas , Testes Sorológicos/estatística & dados numéricos , Testes Sorológicos/veterinária
4.
Viruses ; 12(6)2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32516914

RESUMO

Infections due to arboviruses (arthropod-borne viruses) have dramatically increased worldwide during the last few years. In humans, symptoms associated with acute infection of most arboviruses are often described as "dengue-like syndrome", including fever, rash, conjunctivitis, arthralgia, and muscular symptoms such as myalgia, myositis, or rhabdomyolysis. In some cases, muscular symptoms may persist over months, especially following flavivirus and alphavirus infections. However, in humans the cellular targets of infection in muscle have been rarely identified. Animal models provide insights to elucidate pathological mechanisms through studying viral tropism, viral-induced inflammation, or potential viral persistence in the muscle compartment. The tropism of arboviruses for muscle cells as well as the viral-induced cytopathic effect and cellular alterations can be confirmed in vitro using cellular models. This review describes the link between muscle alterations and arbovirus infection, and the underlying mechanisms.


Assuntos
Infecções por Arbovirus/virologia , Arbovírus/fisiologia , Doenças Musculares/virologia , Animais , Infecções por Arbovirus/patologia , Arbovírus/genética , Efeito Citopatogênico Viral , Humanos , Músculos/virologia , Doenças Musculares/patologia
6.
PLoS Negl Trop Dis ; 13(9): e0007700, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31509527

RESUMO

BACKGROUND: Rift Valley fever (RVF) is one of the main vector borne zoonotic diseases that affects a wide range of ruminants and human beings in Africa and the Arabian Peninsula. A rapid and specific test for RVF diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. METHODOLOGY/PRINCIPAL FINDINGS: A first-line lateral flow immunochromatographic strip test (LFT) was developed for the detection of the nucleoprotein (N) of the RVF virus (RVFV). Its diagnostic performance characteristics were evaluated using reference stocks isolates recovered from different hosts and in geographic regions mimicking clinical specimens and from known RVF negative serum samples. A high level of diagnostic accuracy (DSe (35/35), DSp (167/169)) was observed, including the absence of cross-reactivity with viruses belonging to different genera. CONCLUSION/SIGNIFICANCE: The fact no specialized reagents and laboratory equipment are needed, make this assay a valuable, first-line diagnostic tool in resource-poor diagnostic territories for on-site RVFV detection, however the staff require training.


Assuntos
Imunoensaio/métodos , Febre do Vale de Rift/diagnóstico , Vírus da Febre do Vale do Rift/isolamento & purificação , Animais , Artiodáctilos/virologia , Culicidae/virologia , Nucleoproteínas/análise , Febre do Vale de Rift/sangue , Febre do Vale de Rift/virologia , Sensibilidade e Especificidade
7.
Sci Rep ; 9(1): 12404, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455867

RESUMO

Hantaviruses are zoonotic agents transmitted from small mammals, mainly rodents, to humans, where they provoke diseases such as Hemorrhagic fever with Renal Syndrome (HFRS) and its mild form, Nephropathia Epidemica (NE), or Hantavirus Cardio-Pulmonary Syndrome (HCPS). Hantaviruses are spread worldwide and monitoring animal reservoirs is of primary importance to control the zoonotic risk. Here, we describe the development of a pan-viral resequencing microarray (PathogenID v3.0) able to explore the genetic diversity of rodent-borne hantaviruses endemic in Europe. Among about 800 sequences tiled on the microarray, 52 correspond to a tight molecular sieve of hantavirus probes covering a large genetic landscape. RNAs from infected animal tissues or from laboratory strains have been reverse transcribed, amplified, then hybridized to the microarray. A classical BLASTN analysis applied to the sequence delivered through the microarray allows to identify the hantavirus species up to the exact geographical variant present in the tested samples. Geographical variants of the most common European hantaviruses from France, Germany, Slovenia and Finland, such as Puumala virus, Dobrava virus and Tula virus, were genetically discriminated. Furthermore, we precisely characterized geographical variants still unknown when the chip was conceived, such as Seoul virus isolates, recently emerged in France and the United Kingdom.


Assuntos
Variação Genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Orthohantavírus/genética , Europa (Continente) , Orthohantavírus/classificação , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/patologia , Humanos , Filogenia , Filogeografia , Virus Puumala/classificação , Virus Puumala/genética , RNA Viral/genética , RNA Viral/metabolismo
8.
Viruses ; 11(8)2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390747

RESUMO

Genetic variants of Thailand orthohantavirus (THAIV) have been recently reported from rodents in South-East Asia and in islands from the South-West part of the Indian Ocean. In order to detect THAIV and its variants, we developed a sensitive and specific real-time RT-PCR targeting the S segment. Our assay was developed in two different RT-PCR systems that gave similar results in terms of sensitivity. Moreover, our results demonstrated a specificity of 100%.


Assuntos
Infecções por Hantavirus/diagnóstico , Orthohantavírus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Virologia/métodos , Animais , Orthohantavírus/genética , Infecções por Hantavirus/virologia , RNA Viral/genética , Ratos , Sensibilidade e Especificidade , Proteínas Virais/genética
9.
Virol J ; 15(1): 83, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743115

RESUMO

BACKGROUND: Hantavirus infection is a zoonotic disease that is associated with hemorrhagic fever with renal syndrome and cardiopulmonary syndrome in human. Anjozorobe virus, a representative virus of Thailand orthohantavirus (THAIV), was recently discovered from rodents in Anjozorobe-Angavo forest in Madagascar. To assess the circulation of hantavirus at the national level, we carried out a survey of small terrestrial mammals from representative regions of the island and identified environmental factors associated with hantavirus infection. As we were ultimately interested in the potential for human exposure, we focused our research in the peridomestic area. METHODS: Sampling was achieved in twenty districts of Madagascar, with a rural and urban zone in each district. Animals were trapped from a range of habitats and examined for hantavirus RNA by nested RT-PCR. We also investigated the relationship between hantavirus infection probability in rats and possible risk factors by using Generalized Linear Mixed Models. RESULTS: Overall, 1242 specimens from seven species were collected (Rattus rattus, Rattus norvegicus, Mus musculus, Suncus murinus, Setifer setosus, Tenrec ecaudatus, Hemicentetes semispinosus). Overall, 12.4% (111/897) of Rattus rattus and 1.6% (2/125) of Mus musculus were tested positive for THAIV. Rats captured within houses were less likely to be infected than rats captured in other habitats, whilst rats from sites characterized by high precipitation and relatively low seasonality were more likely to be infected than those from other areas. Older animals were more likely to be infected, with infection probability showing a strong increase with weight. CONCLUSIONS: We report widespread distribution of THAIV in the peridomestic rats of Madagascar, with highest prevalence for those living in humid areas. Although the potential risk of infection to human may also be widespread, our results provide a first indication of specific zone with high transmission. Gathered data will be helpful to implement policies for control and prevention of human risk infection.


Assuntos
Animais Selvagens/virologia , Reservatórios de Doenças/virologia , Eulipotyphla/virologia , Infecções por Hantavirus/veterinária , Orthohantavírus/genética , Doenças dos Roedores/epidemiologia , Fatores Etários , Animais , Peso Corporal , Monitoramento Epidemiológico , Feminino , Orthohantavírus/classificação , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/transmissão , Infecções por Hantavirus/virologia , Humanos , Umidade , Madagáscar/epidemiologia , Masculino , Camundongos , Filogenia , Filogeografia , Ratos , Fatores de Risco , Doenças dos Roedores/transmissão , Doenças dos Roedores/virologia
10.
Virology ; 503: 76-82, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28135660

RESUMO

Central African tropical forests are home to several species of non-human primates (NHPs), infected by Simian Immunodeficiency Virus (SIV). It is well-known that HIV-1 epidemic is due to cross-transmission and adaptation of SIV to humans. The main goal of this work was to investigate if a NHP bite is a risk factor for SIV acquisition. A cross-sectional study was performed in rural Cameroon on 246 bitten individuals (mostly by adult NHPs), matched, according to sex, age, and ethnicity (Bantus and Pygmies), with an equal number of not-bitten subjects. Following a serological assay for a wide range of SIVs, we observed a high level of indeterminate seroreactivity (25.8%) in the total population, whereas 68.9% were sero-negative and 5.3% HIV-1 positive. Bites do not appear to be a risk factor for SIV seroreactivity, in contrast to Simian Foamy Virus and Simian T-Lymphotropic Virus type 1 in the same studied population.


Assuntos
Mordeduras e Picadas/epidemiologia , Infecções por Retroviridae/epidemiologia , Infecções por Retroviridae/transmissão , Zoonoses/epidemiologia , Zoonoses/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Camarões/epidemiologia , Cercopithecus , Criança , Pré-Escolar , Estudos Transversais , Feminino , Gorilla gorilla , Humanos , Masculino , Pessoa de Meia-Idade , Pan troglodytes , Infecções por Retroviridae/virologia , Fatores de Risco , Vírus da Imunodeficiência Símia/imunologia , Vírus Linfotrópico T Tipo 1 de Símios/imunologia , Vírus Espumoso dos Símios/imunologia , Inquéritos e Questionários , Adulto Jovem , Zoonoses/virologia
11.
Clin Infect Dis ; 63(6): 800-803, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27325689

RESUMO

Molecular screening of 300 at-risk people from Central Africa identified 2 human T-lymphotropic virus (HTLV)-4-infected individuals. A zoonotic origin of infection was suggested, as both individuals reported being severely bitten by a gorilla during hunting activities. One strain was highly divergent and was designated as the HTLV-4 subtype-b prototype.


Assuntos
Mordeduras e Picadas/virologia , Infecções por Deltaretrovirus , Deltaretrovirus/genética , Gorilla gorilla/virologia , Zoonoses , Idoso , Animais , DNA Viral/sangue , DNA Viral/genética , Infecções por Deltaretrovirus/transmissão , Infecções por Deltaretrovirus/veterinária , Infecções por Deltaretrovirus/virologia , Gabão , Humanos , Masculino , Pessoa de Meia-Idade , Zoonoses/transmissão , Zoonoses/virologia
12.
J Gen Virol ; 97(5): 1060-1065, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26932442

RESUMO

Hantaviruses are emerging zoonotic viruses that cause human diseases. In this study, sera from 642 mammals from La Réunion and Mayotte islands (Indian Ocean) were screened for the presence of hantaviruses by molecular analysis. None of the mammals from La Réunion island was positive, but hantavirus genomic RNA was discovered in 29/160 (18 %) Rattus rattus from Mayotte island. The nucleoprotein coding region was sequenced from the liver and spleen of all positive individuals allowing epidemiological and intra-strain variability analyses. Phylogenetic analysis based on complete coding genomic sequences showed that this Murinae-associated hantavirus is a new variant of Thailand virus. Further studies are needed to investigate hantaviruses in rodent hosts and in Haemorrhagic Fever with Renal Syndrome (HFRS) human cases.


Assuntos
Infecções por Hantavirus/veterinária , Orthohantavírus/isolamento & purificação , Ratos , Doenças dos Roedores/virologia , Animais , Comores/epidemiologia , Feminino , Variação Genética , Orthohantavírus/classificação , Orthohantavírus/genética , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Masculino , Filogenia , Doenças dos Roedores/epidemiologia
13.
Clin Infect Dis ; 60(11): 1667-76, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25722199

RESUMO

BACKGROUND: HTLV-1 infection is endemic to Central African populations. The risk factors for HTLV-1 acquisition in humans via the interspecies transmission of STLV-1 (its simian counterpart) remain largely unknown. METHODS: We studied 269 individuals (254 men, 15 women) bitten by a nonhuman primate (NHP), mostly during hunting activities. These, Pygmies and Bantus, living in the southern Cameroonian rainforest, were matched for sex, age, and ethnicity with individuals from the same settlements reporting no NHP bites. HTLV-1 serology was performed by Western blot on plasma samples. PCR was carried out for HTLV-1 provirus on buffy-coat DNAs. The amplified products were sequenced and analyzed by phylogenetic analyses. RESULTS: HTLV-1 prevalence was 8.6% (23/269) in individuals with bites, vs 1.5% (4/269) in matched controls (P < .001). Moreover, HTLV-1 infection was linked to bite severity. The 23 HTLV-1-positive bitten individuals reported being bitten by a gorilla (17), chimpanzee (3), or small monkey (3). Thirteen (56%) were coinfected with a simian foamy virus known to be acquired through severe bites. Mother-to-child infection was excluded in 6 HTLV-1-infected bitten individuals. All the HTLV-1-positive hunters bitten by a gorilla or chimpanzee were infected with a subtype B strain similar to that present in apes from the same area. Two hunters bitten by small monkeys (C. agilis in one case) were infected with a HTLV-1 subtype F strain very similar to the STLV-1 strains present in such monkeys. CONCLUSIONS: These results strongly suggest ongoing direct zoonotic acquisition of STLV-1 in humans through severe NHP bites during hunting activities.


Assuntos
Mordeduras e Picadas/complicações , Infecções por HTLV-I/epidemiologia , Doenças Profissionais/epidemiologia , Primatas , Adulto , Animais , Anticorpos Antivirais/sangue , Western Blotting , Camarões/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos
14.
PLoS One ; 9(11): e109301, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25383888

RESUMO

There are more than 40 human papillomaviruses (HPVs) belonging to the alpha genus that cause sexually transmitted infections; these infections are among the most frequent and can lead to condylomas and anogenital intra-epithelial neoplasia. At least 18 of these viruses are causative agents of anogenital carcinomas. We evaluated the performance of a resequencing microarray for the detection and genotyping of alpha HPV of clinical significance using cloned HPV DNA. To reduce the number of HPV genotypes tiled on microarray, we used reconstructed ancestral sequences (RASs) as they are more closely related to the various genotypes than the current genotypes are among themselves. The performance of this approach was tested by genotyping with a set of 40 cervical smears already genotyped using the commercial PapilloCheck kit. The results of the two tests were concordant for 70% (28/40) of the samples and compatible for 30% (12/40). Our findings indicate that RASs were able to detect and identify one or several HPV in clinical samples. Associating RASs with homonym sequences improved the genotyping of HPV present in cases of multiple infection. In conclusion, we demonstrate the diagnostic potential of resequencing technology for genotyping of HPV, and illustrate its value both for epidemiological studies and for monitoring the distribution of HPV in the post-vaccination era.


Assuntos
Alphapapillomavirus/genética , DNA Viral/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Filogenia , Esfregaço Vaginal/métodos , Sequência de Bases , Análise por Conglomerados , Primers do DNA/genética , Feminino , Genótipo , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
16.
J Clin Microbiol ; 50(5): 1663-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22403426

RESUMO

Human T-cell leukemia virus (HTLV) indeterminate Western blot (WB) serological patterns are frequently observed in plasma/serum from persons living in intertropical areas. In the framework of ongoing projects on HTLV-1/2 and related viruses in Central Africa, we systematically analyzed plasma from villagers living in South Cameroon by WB. The group included 1,968 individuals (mean age, 44 years; age range, 5 to 90 years; 978 women/990 men), both Bantus (1,165) and Pygmies (803). Plasma samples were tested by WB analysis (MPD HTLV Blot 2.4) and interpreted according to the manufacturer's instructions. Only clear bands were considered in the analysis. Among the 1,968 plasma samples, 38 (1.93%) were HTLV-1, 13 (0.66%) were HTLV-2, and 6 (0.3%) were HTLV WB seropositive. Furthermore, 1,292 (65.65%) samples were WB sero-indeterminate, including 104 (5.28%) with an HTLV-1 Gag-indeterminate pattern (HGIP) and 68 (3.45%) with a peculiar yet unreported pattern exhibiting mostly a strong shifted GD21 and a p28. The other 619 (31.45%) samples were either WB negative or exhibited other patterns, mostly with unique p19 or p24 bands. DNA, extracted from peripheral blood buffy coat, was subjected to PCR using several primer pairs known to detect HTLV-1/2/3/4. Most DNAs from HTLV-1- and HTLV-seropositive individuals were PCR positive. In contrast, all the others, from persons with HTLV-2, HGIP, new WB, and other indeterminate patterns, were PCR negative. Epidemiological determinant analysis of the persons with this new peculiar WB pattern revealed that seroprevalence was independent from age, sex, or ethnicity, thus resembling the indeterminate profile HGIP rather than HTLV-1. Moreover, this new pattern persists over time.


Assuntos
Anticorpos Antivirais/sangue , Western Blotting/métodos , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Leucemia de Células T/epidemiologia , Adolescente , Adulto , África Central/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Etnicidade , Feminino , Humanos , Leucemia de Células T/virologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Estudos Soroepidemiológicos , Adulto Jovem
17.
PLoS One ; 5(3): e9496, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20209110

RESUMO

BACKGROUND: Continued development of in-vitro procedures for expansion and differentiation of erythroid progenitor cells (EPC) is essential not only in hematology and stem cell research but also virology, in light of the strict erythrotropism of the clinically important human parvovirus B19. METHODOLOGY/PRINCIPAL FINDINGS: We cultured EPC directly from ordinary blood samples, without ex vivo stem cell mobilization or CD34+ cell in vitro preselection. Profound increase in the absolute cell number and clustering activity were observed during culture. The cells obtained expressed the EPC marker combination CD36, CD71 and glycophorin, but none of the lymphocyte, monocyte or NK markers. The functionality of the generated EPC was examined by an in vitro infection assay with human parvovirus B19, tropic for BFU-E and CFU-E cells. Following infection (i) viral DNA replication and mRNA production were confirmed by quantitative PCR, and (ii) structural and nonstructural proteins were expressed in >50% of the cells. As the overall cell number increased 100-200 fold, and the proportion of competent EPC (CD34+ to CD36+) rose from <0.5% to >50%, the in vitro culture procedure generated the EPC at an efficiency of >10,000-fold. Comparative culturing of unselected PBMC and ex vivo-preselected CD34+ cells produced qualitatively and quantitatively similar yields of EPC. CONCLUSIONS/SIGNIFICANCE: This approach yielding EPC directly from unmanipulated peripheral blood is gratifyingly robust and will facilitate the study of myeloid infectious agents such as the B19 virus, as well as the examination of erythropoiesis and its cellular and molecular mechanisms.


Assuntos
Técnicas de Cultura de Células , Células Precursoras Eritroides/citologia , Técnicas Genéticas , Antígenos CD/biossíntese , Antígenos CD34/biossíntese , Antígenos CD36/biossíntese , Citometria de Fluxo/métodos , Glicoforinas/biossíntese , Mobilização de Células-Tronco Hematopoéticas/métodos , Humanos , Parvovirus/metabolismo , Reação em Cadeia da Polimerase , Receptores da Transferrina/biossíntese , Pesquisa com Células-Tronco , Células-Tronco
19.
J Gen Virol ; 89(Pt 12): 3034-3038, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19008390

RESUMO

Parvovirus B19 has been associated with liver dysfunction and has been considered a potential aetiological agent of fulminant hepatitis and hepatitis-associated aplastic anaemia. The possible effects of B19 virus infection on the liver have been investigated using HepG2 hepatocellular carcinoma cells as a model system, but the reported results are inconsistent. To investigate this relationship further, this study followed the course of B19 virus infection of HepG2 cells in terms of viral DNA, RNA and protein production by quantitative PCR, RT-PCR and immunofluorescence assays. The data showed that B19 virus is able to bind and possibly enter HepG2 cells, but that viral genome replication or transcription is not supported and that viral proteins are not produced. As far as HepG2 cells can be considered a representative model system, any possible pathogenic role of B19 virus on the liver cannot be ascribed to infection or to a direct cytopathic effect on hepatocytes.


Assuntos
Parvovirus B19 Humano/patogenicidade , Carcinoma Hepatocelular , Linhagem Celular Tumoral , DNA Viral/biossíntese , DNA Viral/genética , Imunofluorescência , Hepatócitos/citologia , Hepatócitos/virologia , Humanos , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/fisiologia , Reação em Cadeia da Polimerase , RNA Viral/biossíntese , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Virais/biossíntese , Proteínas Virais/genética , Virologia/métodos , Replicação Viral
20.
Virology ; 381(2): 168-77, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-18838151

RESUMO

Comprehension of the pathogenetic potential of human parvovirus B19 requires the definition of the complete spectrum of cellular tropism and a functional analysis of the viral genome in infected cells. In this study, we carried out a systematic functional analysis of B19 virus genome in the course of infection of susceptible bone marrow mononuclear cells and myeloblastoid UT7/EpoS1 cells, in terms of dynamics of nucleic acid synthesis. A PCR array was designed and a comprehensive analysis was performed by quantitative PCR and RT-PCR, yielding extended information on the presence and abundance of the diverse classes of viral nucleic acids, on the temporal regulation of genome expression and on its relationship with the cell cycle. The analysis performed indicate that the synthesis of viral nucleic acids is correlated to the progression through the S phase of the cell cycle, that an extended pattern of transcriptional activity occurs throughout the course of infection, with a maximal rate of transcription preceding the onset of S-phase dependent replication of the viral genome, and that utilization of transcript processing signals is relatively constant throughout the course of infection. The information obtained led to the definition of a unified model of functional and expression profiling of parvovirus B19 genome.


Assuntos
Células da Medula Óssea/virologia , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/metabolismo , Replicação Viral , Células da Medula Óssea/citologia , Linhagem Celular Tumoral , Células Cultivadas , DNA Viral/análise , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Genoma Viral/genética , Humanos , Infecções por Parvoviridae/metabolismo , RNA Viral/análise
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