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1.
BMC Cancer ; 16: 367, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27296171

RESUMO

BACKGROUND: Human papillomavirus DNA detection in head and neck squamous cell carcinoma has been linked to improved patient prognosis. The main aims of the study was to test the hypotheses that HPV16 E6/E7 oncogene and p53 function within tumours were associated with the widely reported improved patient survival and prognosis in head and neck cancer. METHODS: HPV16 DNA, mRNA and p53 mRNA presence were analysed in a prospective study of 42 unselected HNSCC patients; correlating the data with patient age, tumour staging/grade, treatment response, disease recurrence and survival. RESULTS: HPV16 DNA and HPV16 mRNA were present in 45.2 % and 21.4 % of patients, respectively. There was a significant positive association between the detection of HPV16 E6/E7 mRNA and p53 mRNA (p = 0.032), but this was not replicated for HPV16 DNA. Five-year disease free survival for the whole cohort was 63 % (CI 52.5-73.5 %). Multivariable analysis revealed only HPV16 E6/E7 mRNA expression to have significant prognostic influence (p = 0.04). CONCLUSIONS: Our study suggests that HPV16 oncogenic transcriptional activity within HNSCC tumours is associated with improved patient survival and better prognosis in a German population. Simple HPV DNA detection alone did not demonstrate this association. The significant association of full-length (wild-type) p53 with HPV16 E6/E7 mRNA is further evidence for a functional relationship, which could contribute to the widely reported improved survival and prognosis. Larger studies are required to validate the frequency of HPV16 mRNA expression in HNSCC.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/metabolismo , Infecções por Papillomavirus/virologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/mortalidade , Papillomavirus Humano 16/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/virologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/mortalidade , Reação em Cadeia da Polimerase , Modelos de Riscos Proporcionais , Estudos Prospectivos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
2.
Virol J ; 10: 137, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23634957

RESUMO

BACKGROUND: The low-risk human papillomavirus types 6 and 11 are responsible for approximately 90% of anogenital wart cases, with approximately 190,000 new and recurrent cases reported in the UK in 2010. The UK has recently selected the quadrivalent HPV vaccine, which conveys protection against both HPV6 and HPV 11, as part of its immunisation programme for 2012 and it is expected that this will reduce disease burden in the UK. The aims of the study were to evaluate current strategies used for the monitoring of HPV infection in genital warts and to assess the suitability of laser-capture microdissection (LCM) as a technique to improve the understanding of the natural history of HPV types associated with genital wart lesions. METHODS: DNA and RNA were extracted from whole wart, surface swabs and LCM sections from 23 patients. HPV types present were determined using the Linear Array HPV Genotyping Test (Roche), with HPV DNA viral load and mRNA expression investigated using qPCR and qRT-PCR, respectively. RESULTS: Results indicated that swabbing the surface of warts does not accurately reflect potential causative HPV types present within a wart lesion, multiple HPV types being present on the surface of the wart that are absent in the lower layers of tissue isolated by LCM. Although it was shown that HPV DNA viral load does not directly correlate with HPV mRNA load, the presence of both DNA and mRNA from a single HPV type suggested a causative role in lesion development in 8/12 (66.6%) of patients analysed, with dual infections seen in 4/12 (33.3%) cases. HPV 6 and HPV 11 were present in more than 90% of the lesions examined. CONCLUSIONS: Surface swabbing of warts does not necessarily reflect the causative HPV types. HPV type specific DNA and mRNA loads do not correlate. HPV 6 and 11 were likely to be causally involved in over 90% of the lesions. Dual infections were also found, and further studies are required to determine the biological and clinical nature of dual/multiple infections and to establish the relationship of multiple HPV types within a single lesion.


Assuntos
Condiloma Acuminado/virologia , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Coinfecção/virologia , DNA Viral/genética , Feminino , Perfilação da Expressão Gênica , Genótipo , Humanos , Papillomaviridae/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reino Unido , Carga Viral
4.
BMC Cancer ; 12: 398, 2012 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-22958276

RESUMO

BACKGROUND: Human papillomavirus (HPV) is well known as the major etiological agent for ano-genital cancer. In contrast to cervical cancer, anal cancer is uncommon, but is increasing steadily in the community over the last few decades. However, it has undergone an exponential rise in the men who have sex with men (MSM) and HIV + groups. HIV + MSM in particular, have anal cancer incidences about three times that of the highest worldwide reported cervical cancer incidences. DISCUSSION: There has therefore traditionally been a lack of data from studies focused on heterosexual men and non-HIV + women. There is also less evidence reporting on the putative precursor lesion to anal cancer (AIN - anal intraepithelial neoplasia), when compared to cervical cancer and CIN (cervical intraepithelial neoplasia). This review summarises the available biological and epidemiological evidence for HPV in the anal site and the pathogenesis of AIN and anal cancer amongst traditionally non-high risk groups. SUMMARY: There is strong evidence to conclude that high-grade AIN is a precursor to anal cancer, and some data on the progression of AIN to invasive cancer.


Assuntos
Neoplasias do Ânus/patologia , Neoplasias do Ânus/virologia , Carcinoma in Situ/virologia , Infecções por Papillomavirus/patologia , Neoplasias do Ânus/epidemiologia , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/patologia , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Infecções por Papillomavirus/epidemiologia
5.
J Med Virol ; 83(8): 1345-50, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21678438

RESUMO

Condylomata acuminata (genital warts) are the most common sexually transmitted viral diseases. These lesions are caused by infection with mucosal human papillomaviruses (HPVs). However, there is limited information on HPV strain distribution involved in the molecular pathogenesis of these lesions. To address this, the strain prevalence and the frequency of multiple HPV infections were determined in wart tissue obtained from 31 patients attending a wart clinic. These lesions were bisected and subjected to parallel DNA and mRNA extractions. HPV-type prevalence and incidence of multiple infections were determined by the Roche Linear Array assay. qPCR compared HPV 6, 11, 16, and 18 viral loads and RT-qPCR measured HPV 6 and 11 E6 genomic expression levels. Seventy-one percent of these samples were infected with multiple HPVs. Only one sample was negative for HPV 6 or 11 DNA. Forty-eight percent of samples were positive for a high risk (oncogenic) HPV. The results show that multiple infections in tissue are frequent and the subsequent analysis of HPV 6 and 11 E6 DNA viral loads suggested that other HPVs could be causing lesions. Further analysis of HPV 6/11 E6 mRNA levels showed that there was no discernable relationship between HPV 6 E6 DNA viral load and relative HPV 6 or 11 E6 mRNA levels thereby questioning the relevance of viral load to lesion causality.


Assuntos
Condiloma Acuminado/epidemiologia , Condiloma Acuminado/virologia , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Carga Viral , Condiloma Acuminado/patologia , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Genótipo , Humanos , Incidência , Masculino , Papillomaviridae/genética , Prevalência , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA Viral/genética , RNA Viral/isolamento & purificação
6.
BMC Cancer ; 11: 473, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22047498

RESUMO

BACKGROUND: Human papillomaviruses (HPV) are causally associated with ano-genital and a subset of head and neck cancers. Rising incidence of HPV+ anal cancers and head and neck cancers have now been demonstrated in the developed world over the last decade. The majority of published data on HPV prevalence at the anal and oro-pharyngeal sites are from studies of higher-risk populations. There is a paucity of data on the prevalence of HPV at non-cervical sites in lower risk, non-HIV+ women and this study was designed to provide initial pilot data on a population of women recalled for colposcopy as part of the UK cervical screening programme. METHODS: 100 non-HIV+ women with abnormal cervical cytology, attending clinic for colposcopic examination were recruited. Swabs from the oro-pharyngeal, anal and cervical sites were taken and DNA extracted. HPV detection and genotyping were performed using a standardised, commercially available PCR-line blot assay, which is used to genotype 37 HPV subtypes known to infect the ano-genital and oro-pharyngeal areas. Strict sampling and laboratory precautions were taken to prevent cross-contamination. RESULTS: There was a very high prevalence of HPV infection at all three sites: 96.0%, 91.4% and 92.4% at the cervix, anus and oro-pharynx, respectively. Multiple HPV subtype infections were dominant at all 3 mucosal sites. At least one or more HR genotype was present at both the cervix/anus in 39/52 (75.0%) patients; both the cervix/oro-pharynx in 48/56 (85.7%) patients; and both the anus/oro-pharynx in 39/52 (75.0%) patients. HPV 16 infection was highly dominant across all mucosal sites, with over a 2-fold increase over the next most prevalent subtype (HPV 31). CONCLUSIONS: Women with abnormal smears have widespread infection with high-risk HPV at the cervical, anal and oro-pharyngeal mucosal sites and may represent a higher risk population for HPV disease in the future.


Assuntos
Canal Anal/virologia , Colo do Útero/patologia , Colo do Útero/virologia , Orofaringe/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Adulto , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/patologia , Projetos Piloto , Reação em Cadeia da Polimerase , Reino Unido/epidemiologia , Adulto Jovem
8.
BMC Cancer ; 9: 440, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20003490

RESUMO

BACKGROUND: Human papillomaviruses (HPV) are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples. METHODS: We compared PGMY09/11, MY09/11 and GP5+/6+ primers sets in PCRs of 34 clinically diagnosed samples of genital warts, cervical brushings (with associated histological diagnosis) and vulval biopsies. All negative samples were subsequently tested using the previously reported PGMY/GP PCR method and amplicons directly sequenced for confirmation and typing. An optimised PCR protocol was then compared to a line blot assay for detection of HPV in 15 oropharyngeal cancer samples. RESULTS: PGMY09/11 primers detected HPV presence in more cervical brushing (100%) and genital wart (92.9%) samples compared to MY09/11 (90% and 64.3%) and GP5+/6+ (80% and 64.3%) primer sets, respectively. From vulval biopsies, HPV detection rates were: MY09/11 (63.6%), GP5+/6+ (54.5%) and PGMY09/11 (54.5%). PGMY/GP nested PCR demonstrated that HPV was present, and direct sequencing confirmed genotypes. This nested PCR protocol showed detection of HPV in 10/15 (66.7%) of oropharyngeal cancer samples. CONCLUSIONS: PGMY09/11 primers are the preferred primer set among these three for primary PCR screening with different clinical samples. MY09/11 and GP5+/6+ may be used (particularly for cervical samples) but demonstrate lower detection rates. A nested PCR approach (i.e. a PGMY-GP system) may be required to confirm negativity or to detect low levels of HPV, undetectable using current primary PCR methods, as demonstrated using oropharyngeal cancer samples.


Assuntos
Primers do DNA , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase/métodos , Condiloma Acuminado/virologia , DNA Viral/análise , DNA Viral/genética , Feminino , Humanos , Neoplasias Vulvares/virologia , Displasia do Colo do Útero
9.
Dermatol Ther (Heidelb) ; 7(2): 249-254, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28484898

RESUMO

INTRODUCTION: Human papillomavirus (HPV) alone is thought to cause ~610,000 cases of cancer per year, and is the dominant aetiological agent for ano-genital (esp. cervical) and head and neck cancers (esp. oropharyngeal). Merkel cell polyomavirus (MCV) is a more recently discovered virus which causes Merkel cell carcinoma, a rare but highly aggressive skin malignancy. METHODS: We explored the available published evidence to see if transmission of live HPV or MCV virus in smoke generated by laser or diathermy was feasible, and would pose an infection risk. Long-term infection with such carcinogenic viruses would then pose an increased risk for the development of virus-induced cancers in medical personnel. RESULTS: The morphological structures of both HPV and MCV are very similar, and the size, external capsids and genomic structures show striking similarity. Both viruses have a non-enveloped external protein capsid consisting of 72 capsomeres, and a double-stranded DNA core. Sizes of both viruses range from 50 to 60 nm. There are now recent data demonstrating live and infectious HPV in smoke, and that these viruses can be used to infect cells in vitro. Further, anecdotal reports of virus transmission leading to disease causation in the production of respiratory airway viral warts (benign disease), and, finally, reports of HPV-induced oropharyngeal carcinoma (malignant disease) in two gynaecological surgeons as an occupational health hazard have been published recently. CONCLUSION: There is now sufficient evidence to support the hypotheses that live infectious carcinogenic viruses can be transmitted via smoke generated from surgical procedures, and, in rare instances, actually cause significant disease. Protective measures such as smoke extraction and airway protection should be instituted for all healthcare personnel, particularly those with multiple repeated exposures such as gynaecological surgeons.

10.
Dermatol Ther (Heidelb) ; 5(3): 201-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26304846

RESUMO

INTRODUCTION: Topical 5-fluorouracil (5-FU) has been used to treat actinic keratosis for decades. It has been an important and effective treatment which the patient can self-administer, but is limited by the surface area of skin to be treated (according to the manufacturer's guidelines) of 500 cm(2). Other topical treatments can be painful, or require hospital/health care professional input. The use of 5-FU under occlusion (chemowraps) for large areas of sun-damaged skin on the arms or legs has been described and is a potentially useful treatment option. We describe our experiences with this technique in the Norfolk and Norwich University Hospital Dermatology Department (Norwich, UK). METHODS: Five patients were recruited into this pilot study. Topical 5-FU was applied to sun-damaged limbs under occlusion, and reviewed weekly for response, and local or systemic side effects. Treatment duration was 12-14 weeks. Clinical photography was undertaken prior to, during, and after treatment to document response. RESULTS: We show that there was substantial clinical improvement in the treated skin in our patients. Experienced dermatologists reviewed all the patients, and documented the changes photographically, and by counting lesions. All patients were satisfied with their treatment regimen, and also with the end result; although two did not complete the treatment regimen due to complications not directly attributable to the treatment. CONCLUSION: Topical 5-FU under occlusion (chemowraps) may be a valid treatment option for large areas of sun-damaged skin with field cancerization changes, due to low systemic and local toxicity, and acceptability to patients.

11.
Eur J Cancer ; 50(15): 2636-48, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25091798

RESUMO

Iatrogenic complications associated with current treatment protocols for oropharyngeal squamous cell carcinoma are noted to cause high rates of acute and chronic morbidity. The aims of this study are to provide an overview of the current de-escalation trials for human papillomavirus positive (HPV+) oropharyngeal carcinoma and to evaluate the evidence supporting improved response to treatment of patients within this viral cohort. This study reviewed all completed or in progress randomised controlled trials (RCTs) assessing clinical interventions for human papillomavirus-associated locally advanced oropharyngeal squamous cell carcinoma. We utilised a validated 'risk of bias' tool to assess study quality. We identified nine RCTs that met the full inclusion criteria for this review (all of which are currently on-going and will report from 2015 onwards). Five RCTs performed a post hoc analysis by HPV status, which allowed meta-analysis of 1130 patients. The data reveal a significant difference in overall survival (hazard ratio (HR) 0.49 [95% confidence interval (CI) 0.35-0.69]), loco-regional failure (HR 0.43 [95% CI 0.17-1.11]) and disease specific survival (0.41 [95% 0.3-0.56]) in favour of the HPV+ category. In considering de-escalation treatment protocols, nine studies are currently ongoing. Our meta-analysis provides strong evidence for an improved prognosis in the viral associated cohort when treated by platinum based chemotherapy in combination with radiotherapy or primary radiotherapy. So far, one trial (with moderate to high risk of bias) suggests a reduced survival outcome for the HPV+ population when using the epidermal growth factor receptor (EGFR) inhibitor cetuximab.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Orofaríngeas/terapia , Infecções por Papillomavirus/terapia , Carcinoma de Células Escamosas/complicações , Quimiorradioterapia/métodos , Protocolos Clínicos , Humanos , Neoplasias Orofaríngeas/complicações , Papillomaviridae/efeitos dos fármacos , Papillomaviridae/fisiologia , Papillomaviridae/efeitos da radiação , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Resultado do Tratamento
12.
Head Neck Oncol ; 1: 36, 2009 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-19828033

RESUMO

The incidence of head and neck squamous cell carcinoma (HNSCC) has been gradually increasing over the last three decades. Recent data have now attributed a viral aetiology to a subset of head and neck cancers. Several studies indicate that oral human papillomavirus (HPV) infection is likely to be sexually acquired. The dominance of HPV 16 in HPV+ HNSCC is even greater than that seen in cervical carcinoma of total worldwide cases. Strong evidence suggests that HPV+ status is an important prognostic factor associated with a favourable outcome in head and neck cancers. Approximately 30 to 40% of HNSCC patients with present with early stage I/II disease. These patients are treated with curative intent using single modality treatments either radiation or surgery alone. A non-operative approach is favored for patients in which surgery followed by either radiation alone or radiochemotherapy may lead to severe functional impairment. Cetuximab, a humanized mouse anti-EGFR IgG1 monoclonal antibody, improved locoregional control and overall survival in combination with radiotherapy in locally advanced tumours but at the cost of some increased cardiac morbidity and mortality. Finally, the improved prognosis and treatment responses to chemotherapy and radiotherapy by HPV+ tumours may suggest that HPV status detection is required to better plan and individualize patient treatment regimes.


Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias de Cabeça e Pescoço/etiologia , Infecções por Papillomavirus/complicações , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Receptores ErbB/antagonistas & inibidores , Neoplasias de Cabeça e Pescoço/terapia , Papillomavirus Humano 16/isolamento & purificação , Humanos , Recidiva Local de Neoplasia , Fatores de Risco , Carga Viral , Integração Viral
13.
Blood ; 99(9): 3335-41, 2002 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11964301

RESUMO

CD4(+) T cells are critical for inducing and maintaining efficient humoral and cellular immune responses to pathogens. The CD4(+) T-cell response in human T-lymphotropic virus 1 (HTLV-1) infection has not been studied in detail. However, CD4(+) T cells have been shown to predominate in early lesions in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). We present direct estimates of HTLV-1 Env- and Tax-specific CD4(+) T-cell frequencies in patients infected with HTLV-1. We first showed that there was a strong bias toward the Th1 phenotype in these HTLV-1-specific CD4(+) T cells in patients with HAM/TSP. We then demonstrated significantly higher frequencies of HTLV-1-specific Th1-type CD4(+) T cells in HAM/TSP patients than in asymptomatic HTLV-1 carriers. The majority of these HTLV-1-specific CD4(+) T cells did not express HTLV-1 Tax and were therefore unlikely to be infected by HTLV-1. High frequencies of activated HTLV-1-specific CD4(+) T cells of the Th1 phenotype might contribute to the initiation or pathogenesis of HAM/TSP and other HTLV-1-associated inflammatory diseases.


Assuntos
Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Paraparesia Espástica Tropical/etiologia , Células Th1/imunologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Citometria de Fluxo , Produtos do Gene tax/imunologia , Produtos do Gene tax/metabolismo , Produtos do Gene tax/farmacologia , Infecções por HTLV-I/sangue , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/química , Humanos , Células Jurkat , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Paraparesia Espástica Tropical/sangue , Paraparesia Espástica Tropical/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/farmacologia
14.
Science ; 299(5613): 1713-6, 2003 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-12589003

RESUMO

Cell contact is required for efficient transmission of human T cell leukemia virus- type 1 (HTLV-I) between cells and between individuals, because naturally infected lymphocytes produce virtually no cell-free infectious HTLV-I particles. However, the mechanism of cell-to-cell spread of HTLV-I is not understood. We show here that cell contact rapidly induces polarization of the cytoskeleton of the infected cell to the cell-cell junction. HTLV-I core (Gag protein) complexes and the HTLV-I genome accumulate at the cell-cell junction and are then transferred to the uninfected cell. Other lymphotropic viruses, such as HIV-1, may similarly subvert normal T cell physiology to allow efficient propagation between cells.


Assuntos
Polaridade Celular , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Junções Intercelulares/fisiologia , Centro Organizador dos Microtúbulos/fisiologia , Linfócitos T/ultraestrutura , Linfócitos T/virologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/ultraestrutura , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/ultraestrutura , Linfócitos T CD8-Positivos/virologia , Moléculas de Adesão Celular/metabolismo , Comunicação Celular , Linhagem Celular , Espaço Extracelular/virologia , Produtos do Gene env/metabolismo , Produtos do Gene gag/metabolismo , Genoma Viral , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Hibridização in Situ Fluorescente , Junções Intercelulares/ultraestrutura , Junções Intercelulares/virologia , Microscopia Confocal , Centro Organizador dos Microtúbulos/ultraestrutura , Microtúbulos/fisiologia , Proteínas do Nucleocapsídeo/metabolismo , Ácidos Nucleicos Peptídicos , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Talina/metabolismo , Vírion/fisiologia
15.
J Immunol ; 173(8): 5121-9, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15470056

RESUMO

The proviral load in human T cell lymphotropic virus type 1 (HTLV-1) infection is typically constant in each infected host, but varies by >1000-fold between hosts and is strongly correlated with the risk of HTLV-1-associated inflammatory disease. However, the factors that determine an individual's HTLV-1 proviral load remain uncertain. Experimental evidence from studies of host genetics, viral genetics, and lymphocyte function and theoretical considerations suggest that a major determinant of the equilibrium proviral load is the CD8+ T cell response to HTLV-1. In this study, we tested the hypothesis that the gene expression profile in circulating CD8+ and CD4+ lymphocytes distinguishes between individuals with a low proviral load of HTLV-1 and those with a high proviral load. We show that circulating CD8+ lymphocytes from individuals with a low HTLV-1 proviral load overexpressed a core group of nine genes with strong functional coherence: eight of the nine genes encode granzymes or other proteins involved in cell-mediated lysis or Ag recognition. We conclude that successful suppression of the HTLV-1 proviral load is associated with strong cytotoxic CD8+ lymphocyte activity in the peripheral blood.


Assuntos
Perfilação da Expressão Gênica , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Provírus/isolamento & purificação , Linfócitos T Citotóxicos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Análise por Conglomerados , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Reação em Cadeia da Polimerase , Carga Viral
16.
J Infect Dis ; 189(12): 2294-8, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15181578

RESUMO

Human T cell lymphotropic virus type 1 (HTLV-1) causes HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). We used interferon- gamma enzyme-linked immunospot assays with overlapping peptides spanning the entire HTLV-1 proteome to test whether the HTLV-1-specific CD8(+) T cells differed significantly in frequency or immunodominance hierarchy between patients with HAM/TSP and asymptomatic carriers and whether the frequency correlated with provirus load. Tax was the immunodominant target antigen. There was no significant qualitative or quantitative difference in the HTLV-1-specific CD8(+) T cell response between the 2 groups. Virus-specific CD8(+) T cell frequency alone does not indicate the effectiveness of the cytotoxic T lymphocyte response in controlling provirus load at equilibrium.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Portador Sadio/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Epitopos Imunodominantes/imunologia , Paraparesia Espástica Tropical/imunologia , Epitopos de Linfócito T/imunologia , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/virologia , Humanos , Interferon gama/biossíntese , Peptídeos/imunologia
17.
J Immunol ; 172(3): 1735-43, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14734756

RESUMO

CD4(+) T cells predominate in early lesions in the CNS in the inflammatory disease human lymphotropic T cell virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), but the pathogenesis of the disease remains unclear and the HTLV-I-specific CD4(+) T cell response has been little studied. We quantified the IFN-gamma-producing HTLV-I-specific CD4(+) T cells, in patients with HAM/TSP and in asymptomatic carriers with high proviral load, to test two hypotheses: that HAM/TSP patients and asymptomatic HTLV-I carriers with a similar proviral load differ in the immunodominance hierarchy or the total frequency of specific CD4(+) T cells, and that HTLV-I-specific CD4(+) T cells are preferentially infected with HTLV-I. The strongest CD4(+) T cell response in both HAM/TSP patients and asymptomatic carriers was specific to Env. This contrasts with the immunodominance of Tax in the HTLV-I-specific CD8(+) T cell response. The median frequency of HTLV-I-specific IFN-gamma(+) CD4(+) T cells was 25-fold greater in patients with HAM/TSP (p = 0.0023, Mann-Whitney) than in asymptomatic HTLV-I carriers with a similar proviral load. Furthermore, the frequency of CD4(+) T cells infected with HTLV-I (expressing Tax protein) was significantly greater (p = 0.0152, Mann-Whitney) among HTLV-I-specific cells than CMV-specific cells. These data were confirmed by quantitative PCR for HTLV-I DNA. We conclude that the high frequency of specific CD4(+) T cells was associated with the disease HAM/TSP, and did not simply reflect the higher proviral load that is usually found in HAM/TSP patients. Finally, we conclude that HTLV-I-specific CD4(+) T cells are preferentially infected with HTLV-I.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Epitopos de Linfócito T/imunologia , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Epitopos Imunodominantes/imunologia , Sequência de Aminoácidos , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Portador Sadio/imunologia , Portador Sadio/patologia , Portador Sadio/virologia , Citomegalovirus/imunologia , Citotoxicidade Imunológica , Mapeamento de Epitopos , Produtos do Gene env/imunologia , Produtos do Gene tax/imunologia , Infecções por HTLV-I/patologia , Infecções por HTLV-I/virologia , Humanos , Contagem de Linfócitos , Dados de Sequência Molecular , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/patologia , Paraparesia Espástica Tropical/virologia , Provírus/imunologia , Carga Viral
18.
J Virol ; 77(17): 9716-22, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12915584

RESUMO

Significantly higher frequencies of tumor necrosis factor alpha- and interleukin-2-secreting human T-lymphotropic virus type 1 (HTLV-1)-specific CD4(+) T cells were present in the peripheral blood mononuclear cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients than in those of asymptomatic carriers with similar provirus loads. The data suggest that HTLV-1-specific CD4(+) T cells play a role in the pathogenesis of HAM/TSP.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Interleucina-2/biossíntese , Paraparesia Espástica Tropical/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Portador Sadio/imunologia , Enterotoxinas/farmacologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Técnicas In Vitro , Interferon gama/biossíntese , Linfotoxina-alfa/biossíntese , Paraparesia Espástica Tropical/etiologia , Provírus/imunologia , Provírus/isolamento & purificação , Acetato de Tetradecanoilforbol/farmacologia
19.
Blood ; 102(12): 4130-6, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12920029

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) infection profoundly alters T-cell gene expression, and the dysregulated synthesis of cytokines could influence the course and pathologic consequences of infection. In the process of screening T-cell lines for T helper 1 (Th1) and Th2 cytokine mRNAs, we observed that interleukin-13 (IL-13) mRNA was highly expressed in HTLV-1-infected, IL-2-dependent T-cell lines. IL-9 and interferon gamma (IFN-gamma) mRNAs were also expressed at high levels in chronically infected cell lines. IL-5 mRNA was detected in 60% of the HTLV-1-infected cell lines, but mRNAs for IL-4, IL-10, IL-2, and IL-15 were either below detection limits or did not correlate with HTLV-1 infection. Transcriptional activation of the IL-13 promoter by the HTLV-1 Tax trans-regulatory protein was demonstrated in Jurkat T cells transiently transfected with an IL-13 promoter-reporter plasmid. The clinical relevance of these observations was demonstrated by immunofluorescent staining and flow cytometry of lymphocytes obtained from HTLV-1-infected patients. These studies revealed that IL-13 production was directly related to the level of Tax expression in the infected CD4+ T cells soon after in vitro culture. As IL-13 plays key roles in tumor immunosurveillance, asthma, and central nervous system inflammation, it may contribute to the pathophysiology of HTLV-1-associated diseases.


Assuntos
Infecções por HTLV-I/patologia , Interleucina-13/biossíntese , Linfócitos T/virologia , Ativação Transcricional , Estudos de Casos e Controles , Linhagem Celular Transformada , Citocinas/biossíntese , Citocinas/genética , Produtos do Gene tax/genética , Produtos do Gene tax/fisiologia , Humanos , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-13/genética , Interleucina-5/biossíntese , Interleucina-5/genética , Interleucina-9/biossíntese , Interleucina-9/genética , Células Jurkat , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Linfócitos T/metabolismo , Transdução Genética
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