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1.
PLoS Genet ; 17(4): e1009324, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33901175

RESUMO

Acquisition of genetic material from viruses by their hosts can generate inter-host structural genome variation. We developed computational tools enabling us to study virus-derived structural variants (SVs) in population-scale whole genome sequencing (WGS) datasets and applied them to 3,332 humans. Although SVs had already been cataloged in these subjects, we found previously-overlooked virus-derived SVs. We detected non-germline SVs derived from squirrel monkey retrovirus (SMRV), human immunodeficiency virus 1 (HIV-1), and human T lymphotropic virus (HTLV-1); these variants are attributable to infection of the sequenced lymphoblastoid cell lines (LCLs) or their progenitor cells and may impact gene expression results and the biosafety of experiments using these cells. In addition, we detected new heritable SVs derived from human herpesvirus 6 (HHV-6) and human endogenous retrovirus-K (HERV-K). We report the first solo-direct repeat (DR) HHV-6 likely to reflect DR rearrangement of a known full-length endogenous HHV-6. We used linkage disequilibrium between single nucleotide variants (SNVs) and variants in reads that align to HERV-K, which often cannot be mapped uniquely using conventional short-read sequencing analysis methods, to locate previously-unknown polymorphic HERV-K loci. Some of these loci are tightly linked to trait-associated SNVs, some are in complex genome regions inaccessible by prior methods, and some contain novel HERV-K haplotypes likely derived from gene conversion from an unknown source or introgression. These tools and results broaden our perspective on the coevolution between viruses and humans, including ongoing virus-to-human gene transfer contributing to genetic variation between humans.


Assuntos
Genoma Humano/genética , Variação Estrutural do Genoma/genética , Interações Hospedeiro-Patógeno/genética , Vírus/genética , Betaretrovirus/genética , Linhagem Celular , Retrovirus Endógenos/genética , Regulação da Expressão Gênica , HIV-1/genética , Herpesvirus Humano 6/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único/genética , Vírus/isolamento & purificação , Sequenciamento Completo do Genoma
2.
Can J Vet Res ; 85(2): 145-150, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33883823

RESUMO

Enzootic nasal adenocarcinoma is a contagious respiratory disease in goats that is caused by the enzootic nasal tumor virus 2 (ENTV-2). In order to increase the number of available detection methods for ENTV-2, we developed a SYBR Green real-time polymerase chain reaction (SGrPCR) assay that targets the gag gene of ENTV-2. The low limit of detection of the assay was 3.68 × 101 copies/µL, a hundredfold more sensitive than conventional PCR. The melt curve showed a single sharp melt peak at 83°C, which indicated that there was no non-specific amplification or primer dimer formation. The intra-assay and inter-assay coefficients of variation were 1.58% and 1.82%, respectively. There was no cross-reactivity with closely related goat viruses (i.e., orf virus, peste des petits ruminants virus, goatpox virus, foot-and-mouth disease virus) and endogenous retroviruses. In conclusion, the SGrPCR assay is specific for the gag gene of ENTV-2 and provides a rapid and sensitive approach for detecting ENTV-2 in clinical samples.


Assuntos
Adenocarcinoma/veterinária , Benzotiazóis/química , Betaretrovirus , Diaminas/química , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Quinolinas/química , Infecções por Retroviridae/veterinária , Infecções Tumorais por Vírus/veterinária , Adenocarcinoma/virologia , Animais , Doenças das Cabras/diagnóstico , Cabras , Neoplasias Nasais/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/virologia
3.
Viruses ; 13(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477490

RESUMO

The assembly of a hexameric lattice of retroviral immature particles requires the involvement of cell factors such as proteins and small molecules. A small, negatively charged polyanionic molecule, myo-inositol hexaphosphate (IP6), was identified to stimulate the assembly of immature particles of HIV-1 and other lentiviruses. Interestingly, cryo-electron tomography analysis of the immature particles of two lentiviruses, HIV-1 and equine infectious anemia virus (EIAV), revealed that the IP6 binding site is similar. Based on this amino acid conservation of the IP6 interacting site, it is presumed that the assembly of immature particles of all lentiviruses is stimulated by IP6. Although this specific region for IP6 binding may be unique for lentiviruses, it is plausible that other retroviral species also recruit some small polyanion to facilitate the assembly of their immature particles. To study whether the assembly of retroviruses other than lentiviruses can be stimulated by polyanionic molecules, we measured the effect of various polyanions on the assembly of immature virus-like particles of Rous sarcoma virus (RSV), a member of alpharetroviruses, Mason-Pfizer monkey virus (M-PMV) representative of betaretroviruses, and murine leukemia virus (MLV), a member of gammaretroviruses. RSV, M-PMV and MLV immature virus-like particles were assembled in vitro from truncated Gag molecules and the effect of selected polyanions, myo-inostol hexaphosphate, myo-inositol, glucose-1,6-bisphosphate, myo-inositol hexasulphate, and mellitic acid, on the particles assembly was quantified. Our results suggest that the assembly of immature particles of RSV and MLV was indeed stimulated by the presence of myo-inostol hexaphosphate and myo-inositol, respectively. In contrast, no effect on the assembly of M-PMV as a betaretrovirus member was observed.


Assuntos
Membrana Celular/química , Membrana Celular/metabolismo , Interações Hospedeiro-Patógeno , Polieletrólitos/química , Retroviridae/fisiologia , Montagem de Vírus , Alpharetrovirus/fisiologia , Animais , Betaretrovirus/fisiologia , Células Cultivadas , Gammaretrovirus/fisiologia , Produtos do Gene gag/química , Produtos do Gene gag/metabolismo , Polieletrólitos/metabolismo , Retroviridae/ultraestrutura , Vírion
4.
Aging (Albany NY) ; 12(16): 15978-15994, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32735554

RESUMO

The betaretrovirus Mouse Mammary Tumor Virus (MMTV) is the well characterized etiological agent of mammary tumors in mice. In contrast, the etiology of sporadic human breast cancer (BC) is unknown, but accumulating data indicate a possible viral origin also for these malignancies. The presence of MMTVenv-like sequences (MMTVels) in the human salivary glands and saliva supports the latter as possible route of inter-human dissemination. In the absence of the demonstration of a mouse-man transmission of MMTV, we considered the possibility that a cross-species transmission could have occurred in ancient times. Therefore, we investigated MMTVels in the ancient dental calculus, which originates from saliva and is an excellent material for paleovirology. The calculus was collected from 36 ancient human skulls, excluding any possible mouse contamination. MMTV-like sequences were identified in the calculus of 6 individuals dated from the Copper Age to the 17th century. The MMTV-like sequences were compared with known human endogenous betaretroviruses and with animal exogenous betaretroviruses, confirming their exogenous origin and relation to MMTV. These data reveal that a human exogenous betaretrovirus similar to MMTV has existed at least since 4,500 years ago and indirectly support the hypothesis that it could play a role in human breast cancer.


Assuntos
Betaretrovirus/isolamento & purificação , Neoplasias da Mama/virologia , Transformação Celular Viral , Infecções por Retroviridae/transmissão , Infecções Tumorais por Vírus/transmissão , Zoonoses Virais/transmissão , Adolescente , Adulto , Animais , Betaretrovirus/genética , Neoplasias da Mama/história , Neoplasias da Mama Masculina/história , Neoplasias da Mama Masculina/virologia , DNA Viral/genética , Feminino , História do Século XV , História do Século XVI , História do Século XVII , História Antiga , História Medieval , Humanos , Masculino , Vírus do Tumor Mamário do Camundongo/genética , Pessoa de Meia-Idade , Filogenia , Infecções por Retroviridae/história , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/história , Infecções Tumorais por Vírus/virologia , Zoonoses Virais/história , Zoonoses Virais/virologia , Adulto Jovem
5.
Comp Med ; 70(1): 75-82, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747991

RESUMO

Despite the lack of confirmed reports of an exogenous Simian betaretrovirus (SRV) isolated from baboons (Papio sp.), reports of simian endogenous gammaretrovirus (SERV) in baboons with complete genomes suggest that such viruses may be potentially infectious. In addition, serologic tests have repeatedly demonstrated antibody reactivity to SRV in baboons from multiple colonies. These findings complicate the management and use of such animals for research. To provide further insight into this situation, we performed in vitro and in vivo studies to determine if baboons are or can be infected with SRV. In our initial experiment, we were not able to isolate SRV from 6 seropositive or sero-indeterminate baboons by coculturing their peripheral blood mononuclear cells (PBMC) with macaque PBMC or permissive cell lines. In a subsequent experiment, we found that baboon PBMC infected in vitro with high dose SRV were permissive to virus replication. To test in vivo infectibil- ity, groups of naive baboons were infused intravenously with either (i) the same SRV tissue culture virus stocks used for the in vitro studies, (ii) SRV antibody positive and PCR positive macaque blood, (iii) SRV antibody positive or indeterminate, but PCR negative baboon blood, or (iv) SRV antibody and PCR negative baboon blood. Sustained SRV infection, as defined by reproducible PCR detection and/or antibody seroconversion, was confirmed in 2 of 3 baboons receiving tissue culture virus but not in any recipients of transfused blood from seropositive macaques or baboons. In conclusion, the data indicate that even though baboon cells can be infected experimentally with high doses of tissue culture grown SRV, baboons that are repeatedly SRV antibody positive and PCR negative are unlikely to be infected with exogenous SRV and thus are unlikely to transmit a virus that would threaten the SPF status of captive baboon colonies.


Assuntos
Doenças dos Macacos/transmissão , Papio , Infecções por Retroviridae/transmissão , Animais , Betaretrovirus/isolamento & purificação , Feminino , Leucócitos Mononucleares/virologia , Masculino , Doenças dos Macacos/sangue , Doenças dos Macacos/virologia , Infecções por Retroviridae/sangue , Infecções por Retroviridae/virologia , Replicação Viral
6.
Infect Genet Evol ; 75: 103995, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31404669

RESUMO

Retroviruses (family Retroviridae) are important agents of humans and animals. This study reports the detection and complete genome characterization of a novel endogenous retrovirus from the black Syrian hamster (Mesocricetus auratus) with a squamous cell skin tumor. The proviral genome, tentatively named black Syrian hamster retrovirus (BSHRV/2013/HUN, MK304634), was 8784 nucleotide in length with typical full-length betaretrovirus genome organization of 5'LTR-gag-pro-pol-env-3'LTR and with a characteristic mouse mammary tumor virus-like (MMTV) betaretrovirus dUTPase domain but without a sag gene. The BSHRV gag (534aa), pro/pol (~1099aa) and env (672aa) proteins had 56%/63%/50% aa identity to the corresponding proteins of MMTV (AF228552). The proviral DNA is detectable in tumor as well as in tumor-free cells by conventional PCR and qPCR but only visible in the tumor cells by in situ hybridization. Low level retroviral RNA expression was found only in the DNase-treated RNA tumor samples using RT/nested PCR. BSHRV/2013/HUN-like betaretrovirus DNA was also identified from a faecal and tissue samples from 1 of the further 3 tested individuals by nested-PCR and qPCR. Further research is needed to investigate the distribution, activity and etiological role of this novel MMTV-like betaretrovirus species in hamster.


Assuntos
Betaretrovirus/classificação , Neoplasias de Células Escamosas/virologia , Neoplasias Cutâneas/virologia , Sequenciamento Completo do Genoma/métodos , Animais , Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , Cadáver , Cricetinae , Fezes/virologia , Feminino , Tamanho do Genoma , Genoma Viral , Masculino , Neoplasias de Células Escamosas/veterinária , Análise de Sequência de RNA , Neoplasias Cutâneas/veterinária , Integração Viral
7.
Ann Clin Lab Sci ; 49(2): 171-174, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31028060

RESUMO

BACKGROUND: Human mammary tumor virus (HMTV) is 90-95% homologous to mouse mammary tumor virus, one of the causal agents of murine mammary tumors. Although HMTV has been frequently detected in human breast cancers, its clinical and prognostic value remains unknown. METHODS: In the present study, we analyzed HMTV infection using polymerase chain reaction (PCR) in 128 breast cancers. RESULTS: HMTV was found in 9.4% (12/128) of breast cancers and was significantly associated with breast pain (66.7% vs. 11.7%, p=0.007). It had a tendency to be detected more frequently in breast cancer patients with lower BMI<25, although this result was not statistically significant (18.8% vs. 5.4%, p=0.103). Kaplan-Meier survival analysis showed no prognostic value of HMTV in breast cancer (χ2=0.148, p=0.700). For the first time, we investigated the clinical and prognostic value of HMTV in Korean patients with breast cancer. CONCLUSION: Although our study revealed that HMTV infection does not have important clinical significance in breast cancer, the possibility remains that it may be a prominent causative agent of the disease.


Assuntos
Grupo com Ancestrais do Continente Asiático , Betaretrovirus/fisiologia , Neoplasias da Mama/virologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
8.
Trop Anim Health Prod ; 51(7): 2095-2098, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30997630

RESUMO

Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (ENTV), which may induce disease in sheep (ENTV-1) and goats (ENTV-2). This study aimed to describe the occurrence of ENT in two Texel sheep (Ovis aries) from a 75-sheep flock, located in the city of Gravataí, southern Brazil. Animals used to be purchased from different origins, and no specific tests for disease monitoring or quarantine procedure were performed. Affected animals presented respiratory distress, anorexia with severe weight loss, and mucopurulent unilateral nasal discharge. Necropsy was performed in both animals and nasal cavity masses were observed. Histopathological analysis demonstrated an epithelial neoplasm compatible with nasal adenocarcinoma. PCR using a protocol that amplifies a 591 bp sequence of 5'LTR-gag region of ENTV1 was performed followed by DNA sequencing. Both samples were positive, and the sequences obtained presented highest identity (97%) with ENTV strain TN28 (GenBank accession number MH899613) detected in a Texel sheep from Scotland. This is the first report of ENTV-1 leading to enzootic nasal tumor in sheep in Latin America, which confirms the presence of the retrovirus in sheep flocks in the Brazilian territory.


Assuntos
Neoplasias Nasais/diagnóstico , Neoplasias Nasais/veterinária , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/veterinária , Animais , Betaretrovirus , Brasil , Doenças das Cabras/virologia , Cabras/virologia , Neoplasias Nasais/virologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Ovinos/virologia , Doenças dos Ovinos/virologia , Infecções Tumorais por Vírus/virologia
9.
Arch Virol ; 164(6): 1647-1650, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877451

RESUMO

Enzootic nasal adenocarcinoma (ENA) of goats, characterized by transformation of epithelial cells of the ethmoid turbinates, is caused by enzootic nasal tumor virus 2 (ENTV-2). ENTV-2 belongs to the genus Betaretrovirus and has extended its distribution globally with a high prevalence; however, the genetic diversity and genotypic distribution for ENTV-2 have not been analyzed systematically due to the limited availability of sequence data. In this study, an infection by ENTV-2 was detected by RT-PCR in Chongqing in July 2018, and the complete sequence of one strain (CQ1) was determined. Phylogenetic analysis indicated a high degree of genetic heterogeneity among ENTV-2 sequences, with the existence of two main lineages. Lineage 1 and 2 were composed of ENTV-2 from China and the UK, respectively. Although CQ1 was closely related to recent ENTV-2 strains collected in the neighboring provinces of Chongqing (Shaanxi and Sichuan), it formed a separate sublineage of lineage 1 (sublineage 1.3). This report will enhance our understanding of the epidemiology of ENTV-2 in China.


Assuntos
Betaretrovirus/classificação , Técnicas de Genotipagem/métodos , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Análise de Sequência de RNA/métodos , Animais , Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , China , Variação Genética , Cabras , Neoplasias Nasais/virologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Reino Unido
10.
Mol Cell Probes ; 44: 51-56, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30771482

RESUMO

Enzootic nasal tumor virus 2 (ENTV-2), the aetiological agent of enzootic nasal adenocarcinoma in goats, is prevalent in China; resulting in substantial economic losses to the goat-breeding industry. Therefore, it is necessary to establish an efficient detection method for the diagnosis and prevention of ENTV-2 infection. More recently, EvaGreen is emerging as a novel alternative fluorescent dye for quantitative real-time PCR because of its low cost, specific amplification and high resolution. In this study, we developed a specific, sensitive, and cost-effective detection method-an EvaGreen-based real-time PCR assay for the detection of ENTV-2. This assay exhibited high specificity and sensitivity and was able to detect ENTV-2 at concentrations as low as 3.0 × 101 copies, which was more sensitive than the conventional PCR method (detection limit, 3.0 × 102 copies). In addition, the reproducibility test indicated that EvaGreen dye in our assay had a good reproducibility. In conclusion, we report that a highly sensitive, specific, and cost-effective EvaGreen-based real-time PCR assay is successful for the rapid detection of ENTV-2.


Assuntos
Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , Neoplasias Nasais/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Zoonoses/virologia , Animais , Primers do DNA/metabolismo , Cabras/virologia , Limite de Detecção , RNA Viral/genética , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Arch Virol ; 164(3): 707-716, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30604242

RESUMO

Enzootic nasal adenocarcinoma (ENA) is a contagious neoplasm of sheep and goats, associated with the oncogenic retroviruses enzootic nasal tumor virus (ENTV) 1 and 2, respectively. It appears to be common in countries with substantial small ruminant-production. ENA diagnosis in goats is based on autopsy and histopathology, and there is no real-time PCR method available for ENTV-2 detection. Here, a novel one-tube real-time RT-PCR (RT-qPCR) method for the detection and quantification of ENTV-2 in nasal swabs is presented. The method targets the env gene/U3 region. For the design of ENTV-2-specific oligonucleotides, molecular characterization of seven Greek ENTV-2 strains was performed. Phylogenetic analysis revealed three distinct phylogenetic clades of ENTV-2 that correlate with the country of sample collection. Evaluation of the analytical performance of the RT-qPCR revealed an amplification efficiency of 92.8% and a linear range of quantification between 2 × 108 and 2 × 102 RNA transcripts. Analysis of nasal swabs from 23 histopathologically confirmed, naturally occurring ENA cases via RT-qPCR yielded positive results. Moreover, modification of the method for use in a real-time PCR (qPCR) assay enables detection of proviral DNA in tumor specimens. Both methods are highly specific and can be used for the confirmation of ENA-suspected cases. Future applications could include ante-mortem diagnosis, verification of the ENTV-2-free status in animal trade, disease surveillance, and control programs.


Assuntos
Betaretrovirus/isolamento & purificação , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções por Retroviridae/veterinária , Infecções Tumorais por Vírus/veterinária , Animais , Betaretrovirus/classificação , Betaretrovirus/genética , Doenças das Cabras/diagnóstico , Cabras , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/virologia , Filogenia , Infecções por Retroviridae/diagnóstico , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/virologia
12.
Virus Res ; 262: 24-29, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29208424

RESUMO

RERV-H was first identified in human tissues and mistaken for a human exogenous retrovirus. However, the integration sites carried by this virus showed that it was instead a European rabbit (Oryctolagus cuniculus) endogenous retrovirus. The first clones retrieved from European rabbit samples represented defective proviruses, although estimation of proviral copy numbers found in the European rabbit genome ranged from hundreds to thousands. Screening for the presence of RERV-H showed the absence of the virus in two other lagomorphs, pika (Ochotona) and hares (Lepus), which diverged from rabbits about 35 and 12 million years ago, respectively. Using a PCR-based approach, samples of seven different Lagomorph genera were tested for the presence of RERV-H. It was possible to amplify a proviral fragment corresponding to RNaseH from Oryctolagus, Bunolagus and Pentalagus genomic samples. The amplification of proviral DNA in species other than Oryctolagus revealed that this virus was endogenized in their common ancestor, roughly 9 million years ago. Using the European rabbit genome sequence OryCun2.0, it was possible to find multiple copies spread throughout the genome and several complete proviral genomes were retrieved. Some copies contained full open reading frames for all viral components. The lack of a complete genome in the other Lagomorph species did not allow further analyses of the provirus, although more deleterious mutations were found in Bunolagus and Pentalagus than in Oryctolagus RNaseH-amplified sequences. To what extent RERV-H and other endogenous viruses might have had an impact on the rabbit genome and its immune system remains elusive.


Assuntos
Betaretrovirus/genética , Retrovirus Endógenos/genética , Evolução Molecular , Provírus/genética , Coelhos/virologia , Animais , Genoma Viral , Genômica , Fases de Leitura Aberta/efeitos dos fármacos , Filogenia , Reação em Cadeia da Polimerase , Ribonuclease H/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-30343707

RESUMO

The human betaretrovirus and the closely related mouse mammary tumor virus have been linked with the development of cholangitis and mitochondrial antibody production in patients with primary biliary cholangitis (PBC) and mouse models of autoimmune biliary disease, respectively. In vitro, betaretroviruses have been found to stimulate the expression of mitochondrial autoantigens on the cell surface of biliary epithelial cells. In vivo, both mitochondrial autoantigens and viral proteins have been shown to be co-expressed in biliary epithelium and lymphoid tissue. Notably, both mice and humans make poor antibody responses to betaretrovirus infection, whereas proinflammatory responses to viral proteins have been observed in T lymphocyte studies. Furthermore, proviral integration studies have confirmed the presence of human betaretrovirus in biliary epithelium of patients with PBC. Preliminary proof of principal studies using combination antiretroviral therapy have shown that suppression of viral expression is associated with sustained biochemical response. As the previous regimen used was poorly tolerated, further randomized controlled trials are planned to determine whether betaretrovirus infection plays an important role in the development of PBC.


Assuntos
Betaretrovirus/isolamento & purificação , Cirrose Hepática Biliar/virologia , Infecções por Retroviridae , Infecções Tumorais por Vírus , Animais , Autoantígenos/imunologia , Doenças Autoimunes , Betaretrovirus/patogenicidade , Humanos
14.
J Med Primatol ; 46(4): 149-153, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28748661

RESUMO

To better understand Simian betaretrovirus (SRV) seropositivity in virus-negative macaques, we transfused blood from SRV-infected or suspect donors into immunosuppressed naive recipients. Our results do not support typical SRV1-5 infection as the cause, but provide evidence for several possibilities including serological artifact, new/different SRV, or an endogenous virus.


Assuntos
Betaretrovirus/fisiologia , Macaca , Doenças dos Macacos/diagnóstico , Infecções por Retroviridae/diagnóstico , Animais , Doenças dos Macacos/virologia , Infecções por Retroviridae/virologia
15.
Virol J ; 14(1): 141, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747230

RESUMO

BACKGROUND: Enzootic nasal tumor virus (ENTV) is a betaretrovirus of sheep (ENTV-1) and goats (ENTV-2) associated with neoplastic transformation of epithelial cells of the ethmoid turbinate. Confirmation of the role of ENTV in the pathogenesis of enzootic nasal adenocarcinoma (ENA) has yet to be resolved due to the inability to culture the virus. Very little is known about the prevalence of this disease, particularly in China. METHODS: To evaluate the genetic diversity of ENTV-2 from Shaanxi province of China, the complete genome sequence of four isolates from Shaanxi province was determined by RT-PCR. These sequences were analyzed to evaluate their genetic relatedness with other small ruminant betaretroviruses. Phylogenetic analyses based on the gag gene and env gene were performed. RESULTS: The ENTV-2-Shaanxi1 genome shared 97.0% sequence identity with ENTV-2-SC (accession number HM104174.1), and 89.6% sequence identity with the ENTV-2 sequences (accession number AY197548.1). ENTV-2 is closely related to the ENTV-1 and jaagsiekte retrovirus (JSRV). The main sequence differences between these viruses reside in LTR, two small regions of Gag, Orf-x, and the transmembrane (TM) region of Env. A stretch of 6 consecutive proline residues exists in VR1 of the ENTV-2-Shaanxi1 ~ 4 isolates. All the ENTV-2-Shaanxi isolates have the YXXM motif in the cytoplasmic tail of the Env. Phylogenetic analysis by nucleotide sequences showed that ENTV-2-Shaanxi1 ~ 4 isolates were closest related to two ENTV-2 isolates published in NCBI, especially with ENTV-2-SC strain. CONCLUSIONS: This finding indicates that ENA most likely was introduced to Shaanxi province by the movement of contaminated goats from other areas in China. This study adds to understand the circulation, variation and distribution of ENTV-2, and may prove beneficial in future control or eradication programmes.


Assuntos
Adenocarcinoma/veterinária , Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , Variação Genética , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Infecções Tumorais por Vírus/veterinária , Adenocarcinoma/virologia , Animais , Betaretrovirus/classificação , China , Cabras , Neoplasias Nasais/virologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Infecções Tumorais por Vírus/virologia , Sequenciamento Completo do Genoma
16.
J Gen Virol ; 98(1): 108-120, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27902399

RESUMO

Enzootic nasal tumor virus (ENTV) and Jaagsiekte sheep retrovirus (JSRV) are highly related ovine betaretroviruses that induce nasal and lung tumours in small ruminants, respectively. While the ENTV and JSRV envelope (Env) glycoproteins mediate virus entry using the same cellular receptor, the glycosylphosphatidylinositol-linked protein hyaluronoglucosaminidase, ENTV Env pseudovirions mediate entry into cells from a much more restricted range of species than do JSRV Env pseudovirions. Unlike JSRV Env, ENTV Env does not induce cell fusion at pH 5.0 or above, but rather requires a much lower pH (4.0-4.5) for fusion to occur. The cytoplasmic tail of retroviral envelope proteins is a key modulator of envelope-mediated fusion and pseudotype efficiency, especially in the context of virions composed of heterologous Gag proteins. Here we report that progressive truncation of the ENTV Env cytoplasmic tail improves transduction efficiency of pseudotyped retroviral vectors and that complete truncation of the ENTV Env cytoplasmic tail increases transduction efficiency to wild-type JSRV Env levels by increasing fusogenicity without affecting sensitivity to inhibition by lysosomotropic agents, subcellular localization or efficiency of inclusion into virions. Truncation of the cytoplasmic domain of ENTV Env resulted in a significant advantage in viral entry into all cell types tested, including foetal ovine lung and nasal cells. Taken together, we demonstrate that the cytoplasmic tail modulates the fusion activity of the ENTV Env protein and that truncation of this region enhances Eenv-mediated entry into target cells.


Assuntos
Betaretrovirus/genética , Betaretrovirus/fisiologia , Deleção de Sequência , Proteínas do Envelope Viral/genética , Internalização do Vírus , Animais , Linhagem Celular , Humanos , Transdução Genética
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 32(9): 1188-92, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-27609573

RESUMO

Objective To explore the influence of the exogenous Jaagsiekte sheep retrovious (exJSRV) envelope protein (Env) on NIH3T3 cell proliferation. Methods A recombinant plasmid pcDNA4/myc-His/exJSRV- env carrying exJSRV- env gene was constructed, and then the correctness of the recombinant plasmid was identified by PCR, restriction enzyme digestion and sequencing. The recombinant plasmid pcDNA4/myc-His/exJSRV- env was transiently transfected into NIH3T3 cells by Lipofectamine(TM) LTX. After the transfection of the recombinant plasmid, the expression of exJSRV- env was detected by reverse transcription PCR and Western blotting. The effect of Env on cell proliferation was investigated by CCK-8 assay and plate colony formation assay. Results The recombinant eukaryotic expression plasmid containing exJSRV- env was successfully constructed as identified by PCR, restriction enzyme identification and sequencing. After the recombinant plasmid was transiently transfected into NIH3T3 cells, reverse transcription PCR and Western blotting showed the expression of exJSRV- env , and Env promoted NIH3T3 cell proliferation significantly. Conclusion JSRV Env was expressed successfully in the NIH3T3 cells and promoted the proliferation of NIH3T3 cells.


Assuntos
Betaretrovirus/genética , Proliferação de Células , Adenomatose Pulmonar Ovina/fisiopatologia , Adenomatose Pulmonar Ovina/virologia , Proteínas do Envelope Viral/genética , Animais , Betaretrovirus/metabolismo , Expressão Gênica , Camundongos , Células NIH 3T3 , Ovinos , Transfecção , Proteínas do Envelope Viral/metabolismo
18.
J Virol ; 90(18): 8132-49, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27384664

RESUMO

UNLABELLED: Retroviruses enter host cells through the interaction of their envelope (Env) protein with a cell surface receptor, which triggers the fusion of viral and cellular membranes. The sodium-dependent neutral amino acid transporter ASCT2 is the common receptor of the large RD114 retrovirus interference group, whose members display frequent env recombination events. Germ line retrovirus infections have led to numerous inherited endogenous retroviruses (ERVs) in vertebrate genomes, which provide useful insights into the coevolutionary history of retroviruses and their hosts. Rare ERV-derived genes display conserved viral functions, as illustrated by the fusogenic syncytin env genes involved in placentation. Here, we searched for functional env genes in the nine-banded armadillo (Dasypus novemcinctus) genome and identified dasy-env1.1, which clusters with RD114 interference group env genes and with two syncytin genes sharing ASCT2 receptor usage. Using ex vivo pseudotyping and cell-cell fusion assays, we demonstrated that the Dasy-Env1.1 protein is fusogenic and can use both human and armadillo ASCT2s as receptors. This gammaretroviral env gene belongs to a provirus with betaretrovirus-like features, suggesting acquisition through recombination. Provirus insertion was found in several Dasypus species, where it has not reached fixation, whereas related family members integrated before diversification of the genus Dasypus >12 million years ago (Mya). This newly described ERV lineage is potentially useful as a population genetic marker. Our results extend the usage of ASCT2 as a retrovirus receptor to the mammalian clade Xenarthra and suggest that the acquisition of an ASCT2-interacting env gene is a major selective force driving the emergence of numerous chimeric viruses in vertebrates. IMPORTANCE: Retroviral infection is initiated by the binding of the viral envelope glycoprotein to a host cell receptor(s), triggering membrane fusion. Ancient germ line infections have generated numerous endogenous retroviruses (ERVs) in nearly all vertebrate genomes. Here, we report a previously uncharacterized ERV lineage from the genome of a xenarthran species, the nine-banded armadillo (Dasypus novemcinctus). It entered the Dasypus genus >12 Mya, with one element being inserted more recently in some Dasypus species, where it could serve as a useful marker for population genetics. This element exhibits an env gene, acquired by recombination events, with conserved viral fusogenic properties through binding to ASCT2, a receptor used by a wide range of recombinant retroviruses infecting other vertebrate orders. This specifies the ASCT2 transporter as a successful receptor for ERV endogenization and suggests that ASCT2-binding env acquisition events have favored the emergence of numerous chimeric viruses in a wide range of species.


Assuntos
Sistema ASC de Transporte de Aminoácidos/metabolismo , Tatus/virologia , Betaretrovirus/isolamento & purificação , Retrovirus Endógenos/isolamento & purificação , Antígenos de Histocompatibilidade Menor/metabolismo , Provírus/isolamento & purificação , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Animais , Betaretrovirus/genética , Retrovirus Endógenos/genética , Testes Genéticos , Provírus/genética , Recombinação Genética , Proteínas do Envelope Viral/genética
19.
J Med Primatol ; 45(2): 55-78, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26932456

RESUMO

Specific pathogen free (SPF) macaques provide valuable animal models for biomedical research. In 1989, the National Center for Research Resources [now Office of Research Infrastructure Programs (ORIP)] of the National Institutes of Health initiated experimental research contracts to establish and maintain SPF colonies. The derivation and maintenance of SPF macaque colonies is a complex undertaking requiring knowledge of the biology of the agents for exclusion and normal physiology and behavior of macaques, application of the latest diagnostic technology, facilitiy management, and animal husbandry. This review provides information on the biology of the four viral agents targeted for exclusion in ORIP SPF macaque colonies, describes current state-of-the-art viral diagnostic algorithms, presents data from proficiency testing of diagnostic assays between laboratories at institutions participating in the ORIP SPF program, and outlines management strategies for maintaining the integrity of SPF colonies using results of diagnostic testing as a guide to decision making.


Assuntos
Macaca , Doenças dos Macacos/diagnóstico , Viroses/veterinária , Algoritmos , Animais , Betaretrovirus/isolamento & purificação , Infecções por Deltaretrovirus/diagnóstico , Infecções por Deltaretrovirus/veterinária , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/veterinária , Herpesvirus Cercopitecino 1/isolamento & purificação , Modelos Animais , Doenças dos Macacos/virologia , Controle de Qualidade , Infecções por Retroviridae/diagnóstico , Infecções por Retroviridae/veterinária , Síndrome de Imunodeficiência Adquirida dos Símios/diagnóstico , Vírus da Imunodeficiência Símia/isolamento & purificação , Vírus Linfotrópico T Tipo 1 de Símios/isolamento & purificação , Organismos Livres de Patógenos Específicos , Viroses/diagnóstico
20.
World J Gastroenterol ; 22(1): 349-60, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26755881

RESUMO

Following the characterization of a human betaretrovirus in patients with primary biliary cirrhosis (PBC), pilot studies using antiretroviral therapy have been conducted as proof of principal to establish a link of virus with disease and with the eventual aim to find better adjunct therapies for patients unresponsive to ursodeoxycholic acid. In the first open label pilot study, the reverse transcriptase inhibitor lamivudine had little demonstrable biochemical or histological effect after 1 year. Whereas, lamivudine in combination with zidovudine was associated with a significant reduction in alkaline phosphatase as well as improvement in necroinflammatory score, cholangitis and ductopenia over a 12 mo period. A double blind, multi-center randomized controlled trial using lamivudine with zidovudine for 6 mo confirmed a significant reduction in alkaline phosphatase, ALT and AST in patients on antiviral therapy. However, none of the patients achieved the stringent endpoint criteria for normalization of alkaline phosphatase. Furthermore, some patients developed biochemical rebound consistent with drug resistance. A major fault of these studies has been the inability to measure the viral load in peripheral blood and therefore, provide a direct correlation between improvement of hepatic biochemistry and reduction in viral load. Nevertheless, viral mutants to lamivudine with zidovudine were later characterized in the NOD.c3c4 mouse model of PBC that has been used to test other antiretroviral regimens to betaretrovirus. The combination of tenofovir and emtricitabine reverse transcriptase inhibitors and the HIV protease inhibitor, lopinavir were found to abrogate cholangitis in the NOD.c3c4 mouse model and the same regimen normalized the liver tests in a PBC patient with HIV and human betaretrovirus infection. This combination antiretroviral therapy has now been used in a double blind randomized controlled crossover study for patients with PBC followed by an open label extension study. Only a third of the PBC patients were able to tolerate the lopinavir but those maintained on tenofovir, emtricitabine and lopinavir experienced sustained and clinically meaningful reduction in hepatic biochemistry. While we await the histological and virological evaluation, it is clear that better tolerated regimens of antiretroviral treatment will be required in future clinical trials.


Assuntos
Antirretrovirais/administração & dosagem , Cirrose Hepática Biliar/tratamento farmacológico , Animais , Betaretrovirus/isolamento & purificação , Betaretrovirus/patogenicidade , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Emtricitabina/administração & dosagem , Humanos , Lamivudina/administração & dosagem , Cirrose Hepática Biliar/virologia , Lopinavir/administração & dosagem , Vírus do Tumor Mamário do Camundongo/patogenicidade , Camundongos , Tenofovir/administração & dosagem , Zidovudina/administração & dosagem
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