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1.
PLoS One ; 9(7): e102501, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25025336

RESUMEN

Over 95% of the adult population worldwide is infected with Epstein-Barr virus (EBV). EBV infection is associated with the development of several cancers, including Hodgkin lymphoma (HL). Elevated levels of anti-EBV antibodies have been associated with increased risk of HL. There is growing evidence that genetic factors control the levels of antibodies against EBV antigens. Here, we conducted linkage and association studies to search for genetic factors influencing either anti-viral capsid antigen (VCA) or anti-Epstein Barr nuclear antigen-1 (EBNA-1) IgG levels in a unique cohort of 424 individuals of European origin from 119 French families recruited through a Hodgkin lymphoma (HL) patient. No major locus controlling anti-VCA antibody levels was identified. However, we found that the HLA region influenced anti-EBNA-1 IgG titers. Refined association studies in this region identified a cluster of HLA class II variants associated with anti-EBNA-1 IgG titers (e.g. p = 5×10(-5) for rs9268403). The major allele of rs9268403 conferring a predisposition to high anti-EBNA-1 antibody levels was also associated with an increased risk of HL (p = 0.02). In summary, this study shows that HLA class II variants influenced anti-EBNA-1 IgG titers in a European population. It further shows the role of the same variants in the risk of HL.


Asunto(s)
Inmunidad Adaptativa/genética , Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/biosíntesis , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Adulto Joven
2.
J Clin Virol ; 56(3): 244-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23182775

RESUMEN

BACKGROUND: Diagnosis of human papillomavirus (HPV) disease remains a challenge due to several factors related to the cost, the workload of available commercial assays to detect and genotype HPV, and to the low prevalence of infected patients. OBJECTIVE: Our study aimed to develop a real-time PCR, based on SPF10 primers, in order to combine HPV-DNA detection and genotype identification avoiding the negative samples. STUDY DESIGN: Validation of SYBR-green based SPF10 real-time PCR on HPV-DNA plasmids followed by the investigation of the viral status in 92 samples from oropharyngeal (94%) cutaneous biopsies (3%) and anal smears (3%) which had previously been HPV-genotyped by LiPA hybridization. In-house HPV viral loads were performed to evaluate the SPF10 real-time PCR sensitivity. RESULTS: Data showed that 100% of HPV plasmids, assessable by LiPA hybridization, were detected and genotyped appropriately after SPF10 real-time PCR assays. These results defined a range of melting temperature peaks for HPV positivity by real-time PCR. The efficient determination of the presence of HPV-DNA by SPF10 real-time PCR was validated for 98% of clinical samples compared to commercial method. Discordant results were due to a low HPV-DNA amount and to a supplementary HPV genotype identified. The SPF10 real-time PCR sensitivity was evaluated between 1 and 10 copies/10(3)cells using in-house HPV (6, 11 and 16) viral load assays. CONCLUSION: The real-time PCR method was efficient in combining screening and genotyping of HPV-DNA. Cost and workload reduction by SPF10 real-time PCR approach may facilitate earlier diagnosis and clinical management of HPV infected patients.


Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Virología/métodos , Canal Anal/virología , Benzotiazoles , Costos y Análisis de Costo , Cartilla de ADN/genética , Diaminas , Genotipo , Humanos , Técnicas de Diagnóstico Molecular/economía , Sondas de Oligonucleótidos/genética , Compuestos Orgánicos/metabolismo , Orofaringe/virología , Quinolinas , Reacción en Cadena en Tiempo Real de la Polimerasa/economía , Sensibilidad y Especificidad , Piel/virología , Coloración y Etiquetado/métodos , Virología/economía
3.
Virology ; 431(1-2): 21-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22664356

RESUMEN

Defective hepatitis B virus (dHBV) generated from spliced RNA is detected in the sera of HBV-chronic carriers. Our study was designed to determine whether the proportion of dHBV changed during the course of infection, and to investigate whether dHBV might interfere with HBV replication. To achieve this, HBV wild-type and dHBV levels were determined by Q-PCR in sera from 56 untreated chronic patients and 23 acute patients, in sequential samples from 4 treated-patients and from liver-humanized mice after HBV infection. The proportion of dHBV was higher in patients with severe compared to null/moderate liver disease or with acute infection. Follow-up showed that the proportion of dHBV increased during disease progression. By contrast, a low and stable proportion of dHBV was observed in the humanized-mouse model of HBV infection. Our results highlight a regulation of the proportion of dHBV during liver disease progression that is independent of interference with viral replication.


Asunto(s)
Virus Defectuosos/crecimiento & desarrollo , Virus de la Hepatitis B/crecimiento & desarrollo , Hepatitis B Crónica/virología , Hígado/virología , Replicación Viral , Adulto , Animales , Virus Defectuosos/aislamiento & purificación , Modelos Animales de Enfermedad , Femenino , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Hígado/patología , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Suero/virología , Carga Viral
4.
Am J Trop Med Hyg ; 82(3): 454-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20207872

RESUMEN

Liver fibrosis (LF) must be assessed before talking treatment decisions in hepatitis B. In Burkina Faso, liver biopsy (LB) remains the "gold standard" method for this purpose. Access to treatment might be simpler if reliable alternative techniques for LF evaluation were available. The hepatitis B virus (HBV)-infected patients who underwent LB was invited to have liver stiffness measurement (Fibroscan) and serum marker assays. Fifty-nine patients were enrolled. The performance of each technique for distinguishing F0F1 from F2F3F4 was compared. The area under receiver operating characteristic (AUROC) curves was 0.61, 0.71, 0.79, 0.82, and 0.87 for the aspartate transaminase to platelet ratio index (APRI), Fib-4, Fibrotest, Fibrometre, and Fibroscan. Elastometric thresholds were identified for significant fibrosis and cirrhosis. Combined use of Fibroscan and a serum marker could avoid 80% of biopsies. This study shows that the results of alternative methods concord with those of histology in HBV-infected patients in Burkina Faso. These alternative techniques could help physicians to identify patients requiring treatment.


Asunto(s)
Biomarcadores/sangre , Diagnóstico por Imagen de Elasticidad , Hepatitis B/complicaciones , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico , Adulto , Antivirales/uso terapéutico , Burkina Faso/epidemiología , Femenino , Hepatitis B/tratamiento farmacológico , Virus de la Hepatitis B , Humanos , Masculino , Carga Viral , Adulto Joven
5.
Clin Infect Dis ; 50(8): 1184-6, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20210647

RESUMEN

We assessed the safety and immunogenicity of hepatitis B vaccination among 40 human immunodeficiency virus-infected patients with isolated positivity for antibodies to hepatitis B core antigen. No baseline factors were found to be predictive of an anamnestic response, which occurred in 32.5% of the patients. The overall response rate among patients without an anamnestic response was 74.0% after 3-6 vaccine doses.


Asunto(s)
Infecciones por VIH/inmunología , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/efectos adversos , Vacunas contra Hepatitis B/inmunología , Adulto , Femenino , Humanos , Memoria Inmunológica , Masculino , Persona de Mediana Edad
6.
J Infect Dis ; 199(8): 1121-7, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19284285

RESUMEN

BACKGROUND: Markers of Epstein-Barr virus (EBV) infection include anti-viral capsid antigen (VCA) immunoglobulin (Ig) G. High anti-VCA titers are associated with EBV-related lymphoproliferation, such as Burkitt lymphoma (BL) and Hodgkin lymphoma (HL). METHODS: Intrafamilial correlations of anti-VCA IgG levels were studied in 3 settings: 127 families recruited through patients with HL in France (population A), 31 families recruited through patients with BL in Uganda (population B), and 74 large families from a general population in Cameroon (population C). Titers were determined by enzyme-linked immunosorbent assay (populations A and C) or by immunofluorescence analysis (population B). RESULTS: In populations A and B, the anti-VCA IgG titers of the relatives of patients with HL or BL increased significantly (P = .01 and P < .001, respectively) with those of the index case patient. In all 3 populations, anti-VCA IgG titers were significantly correlated (P < .001 for A, P = .002 for B, and P < .001 for C) between genetically related individuals (father-offspring, mother-offspring, and sibling-sibling) but not between spouses. Similar results were obtained for population A after adjustment for total IgG levels. In all cases, the pattern of correlations was consistent with a polygenic model, with heritability ranging from 0.32 to 0.48. CONCLUSION: These results provide evidence for the genetic control of anti-VCA IgG titers and pave the way for identification of the loci involved.


Asunto(s)
Anticuerpos Antivirales/sangre , Antígenos Virales/inmunología , Linfoma de Burkitt/virología , Proteínas de la Cápside/inmunología , Herpesvirus Humano 4/inmunología , Enfermedad de Hodgkin/virología , Adolescente , Adulto , Biomarcadores , Linfoma de Burkitt/sangre , Linfoma de Burkitt/inmunología , Camerún , Niño , Preescolar , Análisis por Conglomerados , Familia , Femenino , Francia , Enfermedad de Hodgkin/sangre , Enfermedad de Hodgkin/inmunología , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Uganda , Adulto Joven
7.
J Virol Methods ; 154(1-2): 1-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18929599

RESUMEN

The quantitation of human hepatitis B virus (HBV) in the serum of infected patients is recommended to characterize the course of chronic HBV infection. The aim of this prospective study was to evaluate the performance of the Abbott RealTime PCR assay for HBV DNA quantitation by comparison with the standard Versant HBV DNA 3.0 assay. The better sensitivity and broader dynamic range of HBV DNA quantitation using the Abbott RealTime PCR assay was confirmed by the study of 362 serum samples from 311 patients. In addition, data analysis revealed the concordance of HBV DNA quantitations between the two assays. When this evaluation was assessed as a function of HBV genotype, there was discordance for HBV genotype C samples. Thus, we performed an in-house PCR to confirm the discrepancy observed regarding the HBV genotypes. The in-house PCR results agreed better with the Abbott RealTime PCR method when compared with the standard hybridization assay. In conclusion, the wide dynamic range of HBV DNA quantitation achieved with the Abbott RealTime PCR assay makes it appropriate for the clinical monitoring of HBV infected patients. However, a change of HBV DNA quantitation method could influence results on the follow-up of HBV genotype C infected patients.


Asunto(s)
ADN Viral/sangre , ADN Viral/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Carga Viral , Genotipo , Humanos , Reacción en Cadena de la Polimerasa/métodos , Estudios Prospectivos , Sensibilidad y Especificidad
8.
J Infect Dis ; 198(2): 218-25, 2008 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-18532883

RESUMEN

BACKGROUND: Defective hepatitis B virus (HBV) particles, generated from singly spliced HBV RNA, have been detected in chronic carriers of HBV. The present study was designed to quantify the expression of defective HBV (dHBV) and wild-type HBV (wtHBV) genomes in the serum of patients with HBV infection and its relation to the severity of liver disease. METHODS: HBV and dHBV loads were determined by quantitative polymerase chain reaction in the serum of 89 untreated HBV-infected patients (31 coinfected with human immunodeficiency virus [HIV] type 1) with liver disease of different stages. The ratio of dHBV DNA to total (wtHBV plus dHBV) HBV DNA (dHBV/HBV ratio) was used to express data independently of the level of viral replication. RESULTS: Despite a global correlation between dHBV and wtHBV load, the dHBV/HBV ratio ranged from 0.001% to 69%. The variation in dHBV/HBV ratio was independent of HIV coinfection, HBV genotype, and precore mutations. The mean dHBV/HBV ratio was higher in patients with severe liver necrosis and fibrosis. CONCLUSIONS: Our data indicate that an elevated dHBV/HBV ratio is associated with liver necroinflammation and fibrosis disease, suggesting a regulation of dHBV expression according to the severity of the liver disease. The dHBV/HBV ratio may help to better define liver disease stage during HBV infection.


Asunto(s)
Virus Defectuosos/patogenicidad , Virus de la Hepatitis B/patogenicidad , Hepatitis B/virología , Empalme del ARN , ARN Viral/genética , Portador Sano , ADN Viral/sangre , ADN Viral/genética , Virus Defectuosos/genética , Genoma Viral , Genotipo , Hepatitis B/genética , Virus de la Hepatitis B/genética , Humanos , Inflamación/patología , Inflamación/virología , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Necrosis , Estadísticas no Paramétricas , Carga Viral
11.
J Clin Microbiol ; 44(1): 47-50, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16390946

RESUMEN

Markers of Epstein-Barr virus (EBV) infection include measures of specific serological titers and of viral load (VLo) in peripheral blood mononuclear cells. Few studies have investigated the correlation between these two phenotypes. Here, we found that there was no correlation between VLo and either anti-EBV nuclear antigen type 1 or anti-early antigen immunoglobulin G (IgG) titer but that anti-viral capsid antigen (VCA) IgG titer increased with VLo in peripheral blood mononuclear cells in patients with Hodgkin's lymphoma (P = 3.10(-3)). A similar pattern was observed in healthy first-degree relatives (parents and siblings) of patients (P = 6.10(-4)). Our results indicate that anti-VCA IgG titers and EBV VLo are specifically correlated EBV phenotypes.


Asunto(s)
Anticuerpos Antivirales/análisis , Proteínas de la Cápside/inmunología , Herpesvirus Humano 4/inmunología , Enfermedad de Hodgkin/virología , Inmunoglobulina G/análisis , Linfoma/virología , Infecciones Tumorales por Virus/inmunología , Adolescente , Adulto , Antígenos Virales/inmunología , Femenino , Enfermedad de Hodgkin/inmunología , Humanos , Linfoma/clasificación , Linfoma/inmunología , Masculino , Carga Viral
12.
Inflamm Bowel Dis ; 10(2): 85-90, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15168806

RESUMEN

BACKGROUND: More than 80% of non-Hodgkin lymphomas (NHLs) occurring in transplant recipients on immunosuppressive therapy are associated with Epstein-Barr virus (EBV) infection. EBV viral load (EBV-VL) is predictive of NHL occurrence in this setting. The aim of this work was to determine EBV-VL in patients with Crohn's disease (CD), both according to disease activity and use of immunosuppressive therapy, including infliximab. METHODS: Between December 1999 and July 2001, EBV-VL was determined 212 times by quantitative polymerase chain reaction (PCR) assay in 138 patients with CD and in 24 EBV-seropositive controls free of CD. RESULTS: EBV-VL did not differ significantly between the controls and the patients with CD and was not influenced by CD activity or by immunosuppressive therapy, including recent infliximab infusion. High EBV-VL values were observed in two patients with severe uncontrolled CD, but returned to normal once the flare-up had been controlled (by immunosuppressive drugs in one case and by surgery in the other case). CONCLUSIONS: EBV viral load is on the whole similar in patients with Crohn's disease and in EBV-seropositive controls. Infliximab infusion does not seem to increase significantly EBV-VL in the short-term. However, some patients with Crohn's disease have transient, very high EBV-VL values that are compatible with an increased risk of NHL in the transplant setting. The long-term clinical outcome of these patients must be determined.


Asunto(s)
Linfoma de Burkitt/diagnóstico , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Huésped Inmunocomprometido/inmunología , Inmunosupresores/efectos adversos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Linfoma de Burkitt/epidemiología , Estudios de Casos y Controles , Enfermedad de Crohn/epidemiología , ADN Viral/análisis , Femenino , Estudios de Seguimiento , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Infliximab , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Probabilidad , Valores de Referencia , Medición de Riesgo , Distribución por Sexo , Carga Viral
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