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1.
Infect Genet Evol ; 103: 105337, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35835355

RESUMO

Background HTLV-1-associated myelopathy (HAM/TSP) is a progressive neurodegenerative inflammatory condition of HTLV-1 infection. Viral-host interactions are a significant contributor to the symptoms of HTLV-1-associated diseases. Therefore, in this study, the expression of the main regulatory viral factors and proviral load (PVL) and two host transcription molecules were evaluated in HAM/TSP patients. Materials and methods The study population included 17 HAM/TSP patients, 20 asymptomatic carriers (ACs), and 19 healthy controls (HCs). RNA and DNA were extracted from PBMCs for assessment of the gene expressions and PVL assessment using RT-qPCR and TaqMan method. Results HTLV-1-PVL was higher in HAM/TSPs (395.80 ± 99.69) than ACs (92.92 ± 29.41) (P = 0.001). The Tax expression in HAM/TSPs (7.8 ± 5.7) was strongly higher than ACs (0.06 ± 0.04) (P = 0.02), while HTLV-1-HBZ was only increased around three times in HAM/TSPs (3.17), compared to ACs (1.20) and not significant. The host IRF1 expression in HAM/TSPs (0.4 ± 0.31) was higher than ACs (0.09 ± 0.05) (P = 0.02) and also HCs (0.16 ± 0.07) (P = 0.5), but lower in ACs than HCs (p = 0.01). Although, in HAM/TSPs (0.13 ± 0.09) and ACs (0.03 ± 0.02) CCNA-2 expression was statistically fewer than HCs (0.18 ± 0.06) (P = 0.03, P = 0.001, respectively), in HAM/TSP was higher than ACs (P = 0.1), but did not meet a 95% confidence interval. Conclusion The study showed that HTLV-1-PVL and Tax, along with host IRF-1, could be considered biomarkers in HAM/TSP development. Furthermore, IRF-1, as an essential transcription factor, can be considered a pivotal target in HAM/TSPs treatment.


Assuntos
Ciclina A2 , Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Fator Regulador 1 de Interferon , Paraparesia Espástica Tropical , Proteínas dos Retroviridae , Fatores de Transcrição de Zíper de Leucina Básica/genética , Coevolução Biológica , Ciclina A2/genética , Genes pX , Infecções por HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Fator Regulador 1 de Interferon/genética , Paraparesia Espástica Tropical/genética , Paraparesia Espástica Tropical/virologia , Provírus/genética , Proteínas dos Retroviridae/genética , Carga Viral
2.
J Med Virol ; 93(6): 3865-3870, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32918495

RESUMO

Adult T-cell leukemia (ATL) is a life-threatening malignant neoplasm of CD4+ T cells resulted from human T-cell leukemia virus type I (HTLV-I). Tax1 protein of HTLV-I can induce malignant proliferation of T-cells by modulating the expression of growth factors such as platelet-derived growth factor (PDGF). Here, we aimed to investigate the proviral load (PVL) of HTLV-I in ATL and also to evaluate the mRNA expression of B chain of PDGF and PDGF-ß receptors in ATL patients and HTLV-I-infected healthy carriers. To this end, peripheral blood mononuclear cells (PBMCs) were isolated by using Ficoll-Histophaque density centrifugation. The mean of HTLV-I PVL in ATL patients (42,759 ± 15,737 copies/104 cells [95% CI, 9557-75962]) was significantly (p = .01) higher than that in healthy carriers (650 ± 107 copies/104 cells [95% CI, 422-879], respectively. The HTLV-I PVL in ATL patients exhibited a significant correlation with PBMC count (R = .495, p = .001). The mRNA expression of Tax, B chain of PDGF, and PDGF-ß receptor genes was significantly higher in healthy carriers than in patients with ATL. In conclusion, the expression of the canonical PDGFß and its receptor, and their correlation with Tax expression cannot be a suitable indicator and/or prognostic factor for progression of ATL in HTLV-I carriers.


Assuntos
Genes pX/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Fator de Crescimento Derivado de Plaquetas/genética , Provírus/genética , RNA Mensageiro/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Carga Viral/métodos , Adulto , Progressão da Doença , Feminino , Infecções por HTLV-I/virologia , Voluntários Saudáveis/estatística & dados numéricos , Humanos , Leucemia-Linfoma de Células T do Adulto/virologia , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas/classificação
3.
Am J Pathol ; 191(2): 335-352, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33181139

RESUMO

Human T-lymphotropic virus type 1 (HTLV-1) causes adult T-cell leukemia, a disease commonly associated with hypercalcemia and osteolysis. There is no effective treatment for HTLV-1, and the osteolytic mechanisms are not fully understood. Mice expressing the HTLV-1 oncogene Tax, driven by the human granzyme B promoter (Tax+), develop osteolytic tumors. To investigate the progression of the bone-invasive malignancies, wild-type, Tax+, and Tax+/interferon-γ-/- mice were assessed using necropsy, histologic examination, IHC analysis, flow cytometry, and advanced imaging. Tax+ and Tax+/interferon-γ-/- malignancies of the ear, tail, and foot comprised poorly differentiated, round to spindle-shaped cells with prominent neutrophilic infiltrates. Tail tumors originated from muscle, nerve, and/or tendon sheaths, with frequent invasion into adjacent bone. F4/80+ and anti-mouse CD11b (Mac-1)+ histiocytic cells predominated within the tumors. Three Tax+/interferon-γ-/- cell lines were generated for in vivo allografts, in vitro gene expression and bone resorption assays. Two cell lines were of monocyte/macrophage origin, and tumors formed in vivo in all three. Differences in Pthrp, Il6, Il1a, Il1b, and Csf3 expression in vitro were correlated with differences in in vivo plasma calcium levels, tumor growth, metastasis, and neutrophilic inflammation. Tax+ mouse tumors were classified as bone-invasive histiocytic sarcomas. The cell lines are ideal for further examination of the role of HTLV-1 Tax in osteolytic tumor formation and the development of hypercalcemia and tumor-associated inflammation.


Assuntos
Linhagem Celular Tumoral , Modelos Animais de Doenças , Genes pX , Infecções por HTLV-I/complicações , Sarcoma Histiocítico , Animais , Carcinogênese/genética , Sarcoma Histiocítico/patologia , Sarcoma Histiocítico/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oncogenes , Osteólise/patologia , Osteólise/virologia
4.
PLoS Pathog ; 16(12): e1008504, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33362245

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), and the neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 Tax protein persistently activates the NF-κB pathway to enhance the proliferation and survival of HTLV-1 infected T cells. Lysine 63 (K63)-linked polyubiquitination of Tax provides an important regulatory mechanism that promotes Tax-mediated interaction with the IKK complex and activation of NF-κB; however, the host proteins regulating Tax ubiquitination are largely unknown. To identify new Tax interacting proteins that may regulate its ubiquitination we conducted a yeast two-hybrid screen using Tax as bait. This screen yielded the E3/E4 ubiquitin conjugation factor UBE4B as a novel binding partner for Tax. Here, we confirmed the interaction between Tax and UBE4B in mammalian cells by co-immunoprecipitation assays and demonstrated colocalization by proximity ligation assay and confocal microscopy. Overexpression of UBE4B specifically enhanced Tax-induced NF-κB activation, whereas knockdown of UBE4B impaired Tax-induced NF-κB activation and the induction of NF-κB target genes in T cells and ATLL cell lines. Furthermore, depletion of UBE4B with shRNA resulted in apoptotic cell death and diminished the proliferation of ATLL cell lines. Finally, overexpression of UBE4B enhanced Tax polyubiquitination, and knockdown or CRISPR/Cas9-mediated knockout of UBE4B attenuated both K48- and K63-linked polyubiquitination of Tax. Collectively, these results implicate UBE4B in HTLV-1 Tax polyubiquitination and downstream NF-κB activation.


Assuntos
Produtos do Gene tax/metabolismo , NF-kappa B/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Regulação da Expressão Gênica/genética , Genes pX/fisiologia , Células HEK293 , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Humanos , NF-kappa B/fisiologia , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação , Ubiquitinas/metabolismo
5.
mBio ; 11(3)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487757

RESUMO

Integration of the proviral DNA intermediate into the host cell genome normally represents an essential step in the retroviral life cycle. While the reason(s) for this requirement remains unclear, it is known that unintegrated proviral DNA is epigenetically silenced. Here, we demonstrate that human immunodeficiency virus 1 (HIV-1) mutants lacking a functional integrase (IN) can mount a robust, spreading infection in cells expressing the Tax transcription factor encoded by human T-cell leukemia virus 1 (HTLV-1). In these cells, HIV-1 forms episomal DNA circles, analogous to hepatitis B virus (HBV) covalently closed circular DNAs (cccDNAs), that are transcriptionally active and fully capable of supporting viral replication. In the presence of Tax, induced NF-κB proteins are recruited to the long terminal repeat (LTR) promoters present on unintegrated HIV-1 DNA, and this recruitment in turn correlates with the loss of inhibitory epigenetic marks and the acquisition of activating marks on histones bound to viral DNA. Therefore, HIV-1 is capable of replication in the absence of integrase function if the epigenetic silencing of unintegrated viral DNA can be prevented or reversed.IMPORTANCE While retroviral DNA is synthesized normally after infection by integrase-deficient viruses, the resultant episomal DNA is then epigenetically silenced. Here, we show that expression of the Tax transcription factor encoded by a second human retrovirus, HTLV-1, prevents or reverses the epigenetic silencing of unintegrated HIV-1 DNA and instead induces the addition of activating epigenetic marks and the recruitment of NF-κB/Rel proteins to the HIV-1 LTR promoter. Moreover, in the presence of Tax, the HIV-1 DNA circles that form in the absence of integrase function are not only efficiently transcribed but also support a spreading, pathogenic integrase-deficient (IN-) HIV-1 infection. Thus, retroviruses have the potential to replicate without integration, as is indeed seen with HBV. Moreover, these data suggest that integrase inhibitors may be less effective in the treatment of HIV-1 infections in individuals who are also coinfected with HTLV-1.


Assuntos
Epigênese Genética , Integrase de HIV/genética , HIV-1/genética , Integração Viral/genética , Replicação Viral/genética , Células A549 , Genes pX/genética , Células HEK293 , HIV-1/fisiologia , Células HeLa , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Regiões Promotoras Genéticas , Células THP-1 , Transcrição Gênica
6.
Jpn J Infect Dis ; 73(3): 221-225, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32009059

RESUMO

Adult T-cell leukemia (ATL) is induced by chronic latent infection with human T-cell leukemia virus type 1 (HTLV-1). HTLV-1 Tax is an oncogenic factor that can be targeted by host T-cell responses. However, the expression of Tax in vivo is little in ATL cells and the impact of Tax-specific T-cell responses on ATL progression remains unclear. In the present study, we examined Tax-specific T-cell responses in C57BL/6 mice after syngeneic transplantation with tax-transgenic mouse-derived ATL (mATL) cells. We first confirmed that cellular tax cDNAs are mostly maintained and detectable in the spleen three weeks after mATL cell transplantation. However, mATL cell transplantation did not induce significant Tax-specific T-cell responses. Mice immunized with DNA and adenovirus vectors expressing Tax exhibited Tax-specific CD4+ T-cell responses but showed no enhancement of the responses or reduction in cellular tax cDNA levels after mATL cell transplantation. This study provides an animal model for analyzing the interaction between ATL cells and host immune responses as well as indicates the limited impact of Tax-specific T-cell responses on the proliferation of ATL cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Genes pX/genética , Genes pX/imunologia , Leucemia-Linfoma de Células T do Adulto/imunologia , Adenoviridae/genética , Animais , Modelos Animais de Doenças , Vetores Genéticos , Vírus Linfotrópico T Tipo 1 Humano , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transplante Isogênico , Vacinação
7.
Retrovirology ; 17(1): 2, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915026

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia-lymphoma (ATL) and inflammatory diseases. The HTLV-1 bZIP factor (HBZ) gene is constantly expressed in HTLV-1 infected cells and ATL cells. HBZ protein suppresses transcription of the tax gene through blocking the LTR recruitment of not only ATF/CREB factors but also CBP/p300. HBZ promotes transcription of Foxp3, CCR4, and T-cell immunoreceptor with Ig and ITIM domains (TIGIT). Thus, HBZ is critical for the immunophenotype of infected cells and ATL cells. HBZ also functions in its RNA form. HBZ RNA suppresses apoptosis and promotes proliferation of T cells. Since HBZ RNA is not recognized by cytotoxic T cells, HTLV-1 has a clever strategy for avoiding immune detection. HBZ plays central roles in maintaining infected T cells in vivo and determining their immunophenotype.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Leucemia-Linfoma de Células T do Adulto/virologia , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proliferação de Células , Regulação Viral da Expressão Gênica , Genes pX/genética , Infecções por HTLV-I/fisiopatologia , Infecções por HTLV-I/virologia , Humanos , Proteínas dos Retroviridae/genética , Linfócitos T/imunologia
8.
Virulence ; 11(1): 80-87, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31885330

RESUMO

Bovine leukemia virus (BLV) is an oncogenic retrovirus of the Deltaretrovirus genus, which causes persistent infection in its natural hosts - cattle, zebu, and water buffalo with diverse clinical manifestations through the defeat of B-cells. The BLV proviral genome, along with structural genes (gag, pro, pol, and env), includes nonstructural ones (R3, G4, tax, rex, AS, pre-miRs (for miRNAs). We have shown in our previous data the association of some pre-miRs-B' (for BLV miRNA) alleles with leukocyte (WBC - white blood cell) number in BLV-infected cows. Multifunctional properties of Tax protein have led us to an assumption that tax gene/Tax protein could have too population variations related to WBC counts. Here we report about several tax alleles/Tax protein variants, which have a highly significant association with an increase or a decrease of WBC number in BLV-infected cows. We have provided evidence that Tax A, H variants (tax b, c, d, f, e alleles) are correlated with reduced WBC counts at the level of BLV-negative groups of animals and thus could be the feature of the aleukemic (AL) form of BLV infection. We suggest this finding could be used in BLV testing for the presence of Tax A, H in the proviral DNA consider such strains of BLV as AL ones, and because of this, minimize the clinical losses due to BLV infection in cattle.


Assuntos
Leucose Enzoótica Bovina/genética , Leucose Enzoótica Bovina/virologia , Produtos do Gene tax/genética , Genes pX , Vírus da Leucemia Bovina/genética , Alelos , Sequência de Aminoácidos , Animais , Linfócitos B , Bovinos , Doenças dos Bovinos/virologia , Evolução Molecular , Feminino , Produtos do Gene tax/classificação , Polimorfismo Genético , Alinhamento de Sequência , Análise de Sequência de Proteína
9.
Retrovirology ; 16(1): 33, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775783

RESUMO

The Deltaretrovirus genus of retroviruses (family Retroviridae) includes the human T cell leukemia viruses and bovine leukemia virus (BLV). Relatively little is known about the biology and evolution of these viruses, because only a few species have been identified and the genomic 'fossil record' is relatively sparse. Here, we report the discovery of multiple novel endogenous retroviruses (ERVs) derived from ancestral deltaretroviruses. These sequences-two of which contain complete or near complete internal coding regions-reside in genomes of several distinct mammalian orders, including bats, carnivores, cetaceans, and insectivores. We demonstrate that two of these ERVs contain unambiguous homologs of the tax gene, indicating that complex gene regulation has ancient origins within the Deltaretrovirus genus. ERVs demonstrate that the host range of the deltaretrovirus genus is much more extensive than suggested by the relatively small number of exogenous deltaretroviruses described so far, and allow the evolutionary timeline of deltaretrovirus-mammal interaction to be more accurately calibrated.


Assuntos
Deltaretrovirus/genética , Retrovirus Endógenos/genética , Retrovirus Endógenos/isolamento & purificação , Evolução Molecular , Especificidade de Hospedeiro , Mamíferos/virologia , Animais , Genes pX , Genoma Viral , Humanos , Paleontologia , Filogenia
10.
Retrovirology ; 16(1): 23, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438973

RESUMO

Human T-cell leukemia virus type-1 (HTLV-1) causes adult T-cell leukemia/lymphoma (ATL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and other inflammatory diseases. There is no disease-specific difference in viral strains, and it is unclear how HTLV-1 causes such different diseases manifesting as lymphoproliferation or inflammation. Although some progress has been made in therapies for these diseases, the prognosis for ATL is still dismal and HAM/TSP remains an intractable disease. So far, two regulatory proteins of HTLV-1, Tax and HBZ, have been well studied and shown to have pleiotropic functions implicated in viral pathogenesis. Tax in particular can strongly activate NFκB, which is constitutively activated in HTLV-1-infected cells and considered to contribute to both oncogenesis and inflammation. However, the expression level of Tax is very low in vivo, leading to confusion in understanding its role in viral pathogenesis. A series of studies using IL-2-dependent HTLV-1-infected cells indicated that IL-10, an anti-inflammatory/immune suppressive cytokine, could induce a proliferative phenotype in HTLV-1-infected cells. In addition, type I interferon (IFN) suppresses HTLV-1 expression in a reversible manner. These findings suggest involvement of host innate immunity in the switch between lymphoproliferative and inflammatory diseases as well as the regulation of HTLV-1 expression. Innate immune responses also affect another important host determinant, Tax-specific cytotoxic T lymphocytes (CTLs), which are impaired in ATL patients, while activated in HAM/TSP patients. Activation of Tax-specific CTLs in ATL patients after hematopoietic stem cell transplantation indicates Tax expression and its fluctuation in vivo. A recently developed anti-ATL therapeutic vaccine, consisting of Tax peptide-pulsed dendritic cells, induced Tax-specific CTL responses in ATL patients and exhibited favorable clinical outcomes, unless Tax-defective ATL clones emerged. These findings support the significance of Tax in HTLV-1 pathogenesis, at least in part, and encourage Tax-targeted immunotherapy in ATL. Host innate and acquired immune responses induce host microenvironments that modify HTLV-1-encoded pathogenesis and establish a complicated network for development of diseases in HTLV-1 infection. Both host and viral factors should be taken into consideration in development of therapeutic and prophylactic strategies in HTLV-1 infection.


Assuntos
Genes pX , Infecções por HTLV-I/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Imunoterapia , Leucemia-Linfoma de Células T do Adulto/terapia , Animais , Infecções por HTLV-I/terapia , Humanos , Leucemia-Linfoma de Células T do Adulto/imunologia , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/terapia
11.
Microb Pathog ; 135: 103566, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31252065

RESUMO

BACKGROUND: Breast cancer is one of the most common cancers in the world particularly among Iranian women. Bovine leukemia virus (BLV) is an enzootic, exogenous, and oncogenic retrovirus that causes B-cell leukosis in 1-5% of infected cattle. The current study aimed at evaluating the correlation between BLV infection and breast cancer in an Iranian population. MATERIALS AND TECHNIQUES: A total of 400 samples including 200 breast cancer-suspected tissue samples and 200 blood samples of women without breast cancer, were collected from July 2017 to October 2018 from women referred to two general hospitals in Qom Province, Iran. The nested PCR technique was performed to determine the presence of tax and gag gene of BLV in the collected samples. RESULTS: Out of 200 breast cancer-suspected tissue samples, 172 samples were malignant in terms of pathology. Other samples were reported as non-malignant and non-tumor. Based on nested PCR technique, tax and gag genes of BLV were detected in 30% and 8% of breast cancer-suspected tissue samples, respectively. The frequency of BLV in blood samples collected from women without breast cancer was 16.5% (33/200). CONCLUSION: It seems that human breast cancer and BLV infection in cattle could be associated using nested PCR technique.


Assuntos
Sangue/virologia , Mama/virologia , Infecções por Deltaretrovirus/virologia , Vírus da Leucemia Bovina/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Neoplasias da Mama/sangue , Neoplasias da Mama/virologia , DNA Viral/análise , Infecções por Deltaretrovirus/epidemiologia , Feminino , Genes gag , Genes pX , Humanos , Irã (Geográfico)/epidemiologia , Vírus da Leucemia Bovina/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
12.
Blood Adv ; 3(4): 564-569, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30787019

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATL). The HTLV-1 viral trans-activator/oncoprotein Tax is a major driver of ATL, yet it induces rapid p21Cip1/Waf1 (p21)- and p27Kip1-mediated cellular senescence through constitutive activation (hyperactivation) of NF-κB. Although constitutive NF-κB activation is a common feature of T/B-cell leukemia/lymphoma, including ATL, it is not known how ATL cells maintain chronic NF-κB activation without undergoing senescence. Here, we demonstrate that, in contrast to HTLV-1- T-cell lines, ATL cell lines no longer undergo Tax-induced senescence. Although Tax+ and Tax- ATL cell lines showed signatures of constitutive NF-κB activation, their ability to progress through the cell cycle was unaffected. In some cases, ATL cell lines continued to proliferate despite significant upregulation of p21; additionally, many cell lines displayed altered expression of G1 and G1/S cyclins, particularly overexpression of cyclin D2. We propose that, during the course of ATL development, leukemia cells acquire genetic/epigenetic changes that can mitigate the senescence response triggered by NF-κB hyperactivation. Restoring the NF-κB-induced senescence response would likely help to control the development and progression of ATL and similar lymphoid malignancies.


Assuntos
Genes pX , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Leucemia-Linfoma de Células T do Adulto/imunologia , NF-kappa B/imunologia , Adulto , Ciclo Celular , Linhagem Celular Tumoral , Senescência Celular , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/virologia
13.
J Hematol Oncol ; 11(1): 119, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30231940

RESUMO

BACKGROUND: HTLV-1 is a retrovirus that infects over 20 million people worldwide and is responsible for the hematopoietic malignancy adult T cell leukemia (ATL). We previously demonstrated that Notch is constitutively activated in ATL cells. Activating genetic mutations were found in Notch; however, Notch signaling was also activated in the absence of genetic mutations suggesting the existence of other mechanisms. METHODS: We analyzed the expression of Notch receptor ligands in HTLV-I-transformed cells, ATL patient-derived cell lines, and fresh uncultured ATL samples by RT-PCR, FACS, and immunohistochemistry. We then investigated viral and cellular molecular mechanisms regulating expression of JAG1. Finally, using shRNA knock-down and neutralizing antibodies, we investigated the function of JAG1 in ATL cells. RESULTS: Here, we report the overexpression of the Notch ligand, JAG1, in freshly uncultured ATL patient samples compared to normal PBMCs. We found that in ATL cells, JAG1 overexpression relies upon the viral protein Tax and cellular miR-124a, STAT3, and NFATc1. Interestingly, our data show that blockade of JAG1 signaling dampens Notch1 downstream signaling and limits cell migration of transformed ATL cells. CONCLUSIONS: Our results suggest that targeting JAG1 can block Notch1 activation in HTLV-I-transformed cells and represents a new target for immunotherapy in ATL patients.


Assuntos
Movimento Celular/fisiologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Proteína Jagged-1/biossíntese , Leucemia-Linfoma de Células T do Adulto/metabolismo , Receptor Notch1/metabolismo , Linhagem Celular Transformada , Transformação Celular Viral , Genes pX , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Imuno-Histoquímica , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Células Jurkat , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/virologia , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
14.
J Virol Methods ; 260: 70-74, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30006102

RESUMO

BACKGROUND: Human T-lymphotrophic virus (HTLV) types 1 and 2 cause lifelong infection whereby most infected individuals are asymptomatic whilst a minority develop infection-related disease. These latter patients invariably have been found to have high proviral load (PVL). Therefore, infected patients are monitored by determining the proportion of lymphocytes that are infected with HTLV-1/2. An increase in PVL has been shown to represent an increasing risk of developing HTLV-associated diseases. Monitoring of PVL requires a reliable and sensitive method. In this study assays based on droplet digital PCR (ddPCR) were established and evaluated for detection and quantification of HTLV-1/2. OBJECTIVES: To develop two parallel assays to detect the tax genes and determine the PVL of HTLV-1 and -2. STUDY DESIGN: Sixty-seven clinical samples from patients infected with HTLV-1 or HTLV-2 were analysed. The samples had previously been analysed with a qPCR and a comparison between ddPCR and qPCR was performed. The specificity of the assays were determined by analyzing samples from 20 healthy blood donors. RESULTS: The ddPCR was a stable and sensitive method for detection and quantification of HTLV-1 and -2. When comparing the qPCR and ddPCR the correlation was high (Pearsons correlation coefficient 0.96). The variability of the ddPCR was very low with intra-assay coefficient of variation (CV) of 0.97-3.3% (HTLV-1) and 1.7-8.2% (HTLV-2) and inter-assay CV of 1.8-6.1% (HTLV-1) and 1.2-12.9% (HTLV-2). CONCLUSIONS: The ddPCR reliably quantified HTLV DNA in clinical samples and could be a useful tool for monitoring of PVLs in HTLV-infected individuals.


Assuntos
Infecções por HTLV-I/sangue , Infecções por HTLV-II/sangue , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Provírus/genética , Biomarcadores/sangue , Buffy Coat/virologia , Teste em Amostras de Sangue Seco , Genes pX/genética , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Linfócitos T/virologia
15.
Neurodegener Dis ; 18(2-3): 150-155, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29990995

RESUMO

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic neuroinflammatory disease related to human T lymphotropic virus type 1 (HTLV-1) infection. Interferon type III (IFN-λ), which includes IL28, IL29, and IL28R, and affects the outcome of viral infections, might be complicated in the progression of HAM/TSP. Here, we investigated the host-virus interactions in the manifestation of HAM/TSP, using IL28B, IL29, IL28R, HTLV-1 Tax, HTLV-1 basic leucine zipper factor (HBZ), and proviral load (PVL). The study groups consisted of 20 patients with HAM/TSP, 20 asymptomatic HTLV-1 carriers (ACs), and 20 healthy controls (HCs). The means of PVL, Tax, and HBZ gene expressions in the HAM/TSP group (p = 0.004, 0.006, and < 0.0001, respectively) were significantly higher than in the AC group. The comparison of IL28B, IL29, and IL28R expression in the HAM/TSP, AC, and HC groups revealed no significant difference between the first 2, but lower concentrations in the HCs (IL28B: p = 0.03, 0.01; IL29: p = 0.07, 0.01; and IL28R: p < 0.0001, respectively). In the HAM/TSP group, correlations were seen between Tax and HBZ (R = 0.61, p = 0.004) and between Tax and IL29 (R = 0.45, p = 0.04). Negative correlations were observed between Tax and IL28B (R = -0.49, p = 0.02) and between HBZ and IL28R (R = -0.43, p = 0.06). In the ACs, an inverse correlation was found between Tax and IL28B (R = -0.42, p = 0.06). These findings suggest that IL29, IL28B, and IL28R interfere in the infection of HAM/TSP, mainly via Tax activation.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Genes pX/genética , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Interleucinas/metabolismo , Receptores de Citocinas/metabolismo , Proteínas dos Retroviridae/metabolismo , Adulto , Idoso , Feminino , Humanos , Interferons/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/virologia , Provírus/patogenicidade , Receptores de Interferon , Adulto Jovem , Interferon lambda
16.
Virology ; 520: 39-58, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29777913

RESUMO

The human T-cell leukemia virus type-1 (HTLV-1) is an oncoretrovirus that infects and transforms CD4+ T-cells and causes adult T-cell leukemia/lymphoma (ATLL) -an aggressive lymphoproliferative disease that is highly refractive to most anticancer therapies. The HTLV-1 proviral genome encodes several regulatory products within a conserved 3' nucleotide sequence, known as pX; however, it remains unclear how these factors might cooperate or dynamically interact in virus-infected cells. Here we demonstrate that the HTLV-1 latency-maintenance factor p30II induces the TP53-induced glycolysis and apoptosis regulator (TIGAR) and counters the oxidative stress, mitochondrial damage, and cytotoxicity caused by the viral oncoproteins Tax and HBZ. The p30II protein cooperates with Tax and HBZ and enhances their oncogenic potential in colony transformation/foci-formation assays. Further, we have shown that TIGAR is highly expressed in HTLV-1-induced tumors associated with oncogene dysregulation and increased angiogenesis in an in vivo xenograft model of HTLV-1-induced T-cell lymphoma. These findings provide the first evidence that p30II likely collaborates as an ancillary factor for the major oncoproteins Tax and HBZ during retroviral carcinogenesis.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Produtos do Gene tax/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Linfoma/virologia , Proteínas dos Retroviridae/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Fatores de Transcrição de Zíper de Leucina Básica/genética , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Carcinogênese , Regulação Viral da Expressão Gênica , Genes pX , Xenoenxertos , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Mitofagia , Neovascularização Patológica , Estresse Oxidativo , Monoéster Fosfórico Hidrolases , Espécies Reativas de Oxigênio/metabolismo , Proteínas dos Retroviridae/genética
17.
J Eur Acad Dermatol Venereol ; 32(5): 704-719, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29489036

RESUMO

The term palmoplantar keratoderma (PPK) indicates any form of persistent thickening of the epidermis of palms and soles and includes genetic as well as acquired conditions. We review the nosology of hereditary PPKs that comprise an increasing number of entities with different prognoses, and a multitude of associated cutaneous and extracutaneous features. On the basis of the phenotypic consequences of the underlying genetic defect, hereditary PPKs may be divided into the following: (i) non-syndromic, isolated PPKs, which are characterized by a unique or predominant palmoplantar involvement; (ii) non-syndromic PPKs with additional distinctive cutaneous and adnexal manifestations, here named complex PPKs; (iii) syndromic PPKs, in which PPK is associated with specific extracutaneous manifestations. To date, the diagnosis of the different hereditary PPKs is based mainly on clinical history and features combined with histopathological findings. In recent years, the exponentially increasing use of next-generation sequencing technologies has led to the identification of several novel disease genes, and thus substantially contributed to elucidate the molecular basis of such a heterogeneous group of disorders. Here, we focus on hereditary non-syndromic isolated and complex PPKs. Syndromic PPKs are reviewed in the second part of this 2-part article, where other well-defined genetic diseases, which may present PPK among their phenotypic manifestations, are also listed and diagnostic and therapeutic approaches for PPKs are summarized.


Assuntos
Queratinas/genética , Ceratodermia Palmar e Plantar/genética , Ceratodermia Palmar e Plantar/patologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Antígenos Ly/genética , Proteínas Reguladoras de Apoptose , Aquaporina 5/genética , Proteínas de Transporte/genética , Colágeno/genética , Conexina 43/genética , Desmogleína 1/genética , Desmoplaquinas/genética , Genes pX/genética , Glicoproteínas/genética , Humanos , Ceratodermia Palmar e Plantar/classificação , Metaloendopeptidases/genética , Fenótipo , Serpinas/genética , Canais de Cátion TRPV/genética , Proteínas Supressoras de Tumor/genética , Ativador de Plasminogênio Tipo Uroquinase/genética
18.
Virus Res ; 228: 1-6, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27845163

RESUMO

BACKGROUND: Previous studies have suggested debatable roles of Tax and HBZ gene expression in the pathogenesis of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). In this study, HTLV-1 and host interactions in the manifestation of HAM/TSP were evaluated. METHODS: A cross-sectional study was conducted on 33 HAM/TSP patients and 38 HTLV-1 asymptomatic carriers (ACs). HTLV-1-Tax, HBZ gene expression, and proviral load (PVL) were assessed using the quantitative real-time PCR (TaqMan), host plasma neopterin level, and HLA-I, and the clinical manifestation were evaluated. RESULTS: The HTLV-1 PVLs in HAM/TSP and ACs were 306±360.741 copies/104 PBMCs and 250.98±629.94 copies/104 PBMCs, respectively; the PVL was higher in HAM/TSP than that in ACs (p=0.004). HTLV-1 Tax and HBZ expression in HAM/TSP was higher than that in ACs, wherein only the Tax expression was statistically significant (p=0.039). In contrast to Japanese HTLV-1-infected subjects, HLA-A*02, HLA-A*24, HLA-Cw*08, and HLA-B*5401 did not exhibit preventive effects for HAM/TSP manifestation. The plasma neopterin level was significantly higher in HAM/TSPs than that in ACs; furthermore, there was a strong significant correlation between plasma neopterin and PVL (R=0.76, p=0.001). Moreover, there were significant correlation between urinary disturbances and haematological indices, including the RBC count (R=-0.61, p=0.01) and Hematocrit (Ht) index (R=-0.75, p=0.002), and between mobility disturbances with Tax expression (R=-0.58, p=0.02) and WBC counts (R=-0.54, p=0.04), and finally, a significant association was found between the sensory disturbances and PVL (p=0.05). CONCLUSION: Overall, HTLV-1 PVL and Tax may be the valid predictors of disease development, and the neopterin level may be a valid predictor of disease progression. In addition, Tax and neopterin are more helpful than PVL for the monitoring of HTLV-1-infected patients.


Assuntos
Genes MHC Classe I , Infecções por HTLV-I/genética , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Neopterina/sangue , Paraparesia Espástica Tropical/diagnóstico , Paraparesia Espástica Tropical/etiologia , Adulto , Fatores de Transcrição de Zíper de Leucina Básica/genética , Contagem de Células Sanguíneas , Estudos Transversais , Índices de Eritrócitos , Feminino , Regulação Viral da Expressão Gênica , Genes pX , Infecções por HTLV-I/sangue , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Provírus/genética , Proteínas dos Retroviridae/genética , Avaliação de Sintomas , Carga Viral , Fatores de Virulência/genética
20.
Retrovirology ; 13(1): 56, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27519553

RESUMO

BACKGROUND: Virus transmission from various wild and domestic animals contributes to an increased risk of emerging infectious diseases in human populations. HTLV-1 is a human retrovirus associated with acute T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1 originated from ancient zoonotic transmission from nonhuman primates, although cases of zoonotic infections continue to occur. Similar to HTLV-1, the simian counterpart, STLV-1, causes chronic infection and leukemia and lymphoma in naturally infected monkeys, and combined are called primate T-lymphotropic viruses (PTLV-1). However, other clinical syndromes typically seen in humans such as a chronic progressive myelopathy have not been observed in nonhuman primates. Little is known about the development of neurologic and inflammatory diseases in human populations infected with STLV-1-like viruses following nonhuman primate exposure. RESULTS: We performed detailed laboratory analyses on an HTLV-1 seropositive patient with typical HAM/TSP who was born in Liberia and now resides in the United States. Using a novel droplet digital PCR for the detection of the HTLV-1 tax gene, the proviral load in PBMC and cerebrospinal fluid cells was 12.98 and 51.68 %, respectively; however, we observed a distinct difference in fluorescence amplitude of the positive droplet population suggesting possible mutations in proviral DNA. A complete PTLV-1 proviral genome was amplified from the patient's PBMC DNA using an overlapping PCR strategy. Phylogenetic analysis of the envelope and LTR sequences showed the virus was highly related to PTLV-1 from sooty mangabey monkeys (smm) and humans exposed via nonhuman primates in West Africa. CONCLUSIONS: These results demonstrate the patient is infected with a simian variant of PTLV-1, suggesting for the first time that PTLV-1smm infection in humans may be associated with a chronic progressive neurologic disease.


Assuntos
Infecções por Deltaretrovirus/complicações , Infecções por Deltaretrovirus/virologia , Paraparesia Espástica Tropical/virologia , Vírus Linfotrópico T Tipo 1 de Primatas/isolamento & purificação , África Ocidental , Idoso , Animais , Infecções por Deltaretrovirus/transmissão , Genes pX , Haplorrinos/virologia , Humanos , Leucócitos Mononucleares/virologia , Masculino , Filogenia , Reação em Cadeia da Polimerase , Vírus Linfotrópico T Tipo 1 de Primatas/genética , Vírus Linfotrópico T Tipo 1 de Primatas/patogenicidade , Provírus/genética
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