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1.
Clin Vaccine Immunol ; 19(6): 929-34, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22539474

RESUMO

This study evaluated the performance of two automated Vidas (V) and Liaison (L) immunoassays for Epstein-Barr virus (EBV) serology. The detection of the viral capsid antigen (VCA) IgM, the VCA/early antigen (VCA/EA) IgG, and the Epstein-Barr nuclear antigen (EBNA) IgG was assessed on 526 sera collected for routine EBV testing in immunocompetent subjects. The determination of expected EBV status (186 EBV primary infections, 183 past EBV infections, and 157 EBV-seronegative individuals) was based on results of routine laboratory enzyme immunoassays (EIAs) together with clinical data. The sensitivity and specificity of each individual marker were determined in comparison to the expected EBV status. The agreement between the V and L profiles and the expected EBV status was established through the interpretation of combinations of the different EBV markers. Statistically significant differences between the two tests were found for the specificity of the VCA IgM marker (96.2% for V versus 93.2% for L), the sensitivity of the VCA/EA IgG marker (89% for V versus 94% for L), and the specificity of the EBNA IgG marker (96.5% for V versus 74.2% for L). The results determined for the two assays with respect to overall agreement with the established expected EBV status were not significantly different (89.7% for V versus 88.2% for L), with discrepancies mainly observed in sera referenced as primary infections. These findings demonstrated the similar performances of the Vidas and the Liaison assays for the establishment of an EBV serological status using the VCA, EA, and EBNA markers.


Assuntos
Anticorpos Antivirais/sangue , Automação/métodos , Técnicas de Laboratório Clínico/métodos , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Virologia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
2.
HIV Med ; 13(8): 479-87, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22414000

RESUMO

BACKGROUND: AIDS-related lymphoma (ARL) remains the main cause of AIDS-related deaths in the combined antiretroviral therapy (cART) era. Although most ARLs are associated with the Epstein-Barr virus (EBV), whether patients with high EBV burden are more at risk of developing ARL is unknown. This study investigated the relationship between high blood EBV DNA loads and subsequent progression to ARL. METHODS: We identified 43 cases of ARL diagnosed between 1988 and 2007 within two cohorts (ANRS SEROCO/HEMOCO and PRIMO) and for which stored serum and peripheral blood mononuclear cell (PBMC) samples were available within 3 years before ARL diagnosis. For each case, two controls matched for the cohort and CD4 cell count in the year of ARL diagnosis were selected. EBV DNA was measured in PBMCs and serum samples with a commercial kit. RESULTS: High levels of EBV DNA in PBMCs collected a median of 10 months before diagnosis were associated with an increased risk of developing systemic B lymphoma (adjusted odds ratio 2.47; 95% confidence interval 1.15; 5.32 for each 1 log copies/10(6) PBMC increase in EBV load) but not with primary brain lymphoma. CONCLUSION: In this study, HIV-infected patients with undetectable EBV DNA in PBMCs did not develop ARL in the following 3 years, while high levels of EBV DNA in PBMCs predicted subsequent progression to systemic B lymphoma. Clinicians should be aware of the increased risk of developing systemic B lymphoma in HIV-infected patients with a high blood EBV DNA load.


Assuntos
DNA Viral/sangue , Infecções por HIV/virologia , Herpesvirus Humano 4/isolamento & purificação , Linfoma Relacionado a AIDS/virologia , Linfoma de Células B/virologia , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Progressão da Doença , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Herpesvirus Humano 4/genética , Humanos , Linfoma Relacionado a AIDS/complicações , Masculino , Razão de Chances , Carga Viral
3.
Virologie (Montrouge) ; 11(1): 13-26, 2007 Feb 01.
Artigo em Francês | MEDLINE | ID: mdl-34753254

RESUMO

This review focuses on recent studies that shed new lights on infectious mononucleosis (IM). The major transmission of Epstein-Barr virus (EBV) via saliva is opposed to the possibility of sexual transmission of EBV in developed countries. Multiple infections with different LMP-1 EBV genotypes are frequently observed during IM but with unclear significance. The strict lymphotropism of the virus during primary EBV infection is questioned. Prolonged high EBV-load in saliva is clearly demonstrated during IM and could be explained by a different immune response in tonsil versus blood. Benign and severe IM are also explained by the variability of the immune response. Correlations between severity of IM and high viral load in blood are controversial. A relationship between IM and Hodgkin's disease is suggested by several epidemiological studies. Despite potential new antiviral targets and preliminary human vaccine trials, the lack of curative or preventive treatment against IM is pointed out.

4.
J Clin Microbiol ; 42(1): 242-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14715760

RESUMO

Herpes simplex virus (HSV) infections are very common in the general population and among immunocompromised patients. Acyclovir (ACV) is an effective treatment which is widely used. We deemed it essential to conduct a wide and coordinated survey of the emergence of ACV-resistant HSV strains. We have formed a network of 15 virology laboratories which have isolated and identified, between May 1999 and April 2002, HSV type 1 (HSV-1) and HSV-2 strains among hospitalized subjects. The sensitivity of each isolate to ACV was evaluated by a colorimetric test (C. Danve, F. Morfin, D. Thouvenot, and M. Aymard, J. Virol. Methods 105:207-217, 2002). During this study, 3900 isolated strains among 3357 patients were collected; 55% of the patients were immunocompetent. Only six immunocompetent patients excreted ACV-resistant HSV strains (0.32%), including one female patient not treated with ACV who was infected primary by an ACV-resistant strain. Among the 54 immunocompromised patients from whom ACV-resistant HSV strains were isolated (3.5%), the bone marrow transplantation patients showed the highest prevalence of resistance (10.9%), whereas among patients infected by human immunodeficiency virus, the prevalence was 4.2%. In 38% of the cases, the patients who excreted the ACV-resistant strains were treated with foscarnet (PFA), and 61% of them developed resistance to PFA. The collection of a large number of isolates enabled an evaluation of the prevalence of resistance of HSV strains to antiviral drugs to be made. This prevalence has remained stable over the last 10 years, as much among immunocompetent patients as among immunocompromised patients.


Assuntos
Aciclovir/farmacologia , Antivirais/farmacologia , Simplexvirus/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Transplante de Medula Óssea , Chlorocebus aethiops , Farmacorresistência Viral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos , Células Vero
5.
J Neurovirol ; 9(1): 79-93, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12587071

RESUMO

A retroviral element (multiple sclerosis-associated retrovirus, MSRV) defining a family of genetically inherited endogenous retroviruses (human endogenous retrovirus type W, HERV-W) has been characterized in cell cultures from patients with multiple sclerosis. Recently, MSRV retroviral particles or the envelope recombinant protein were shown to display superantigen activity in vitro, but no animal model has yet been set up for studying the pathogenicity of this retrovirus. In the present study, the pathogenicity of different sources of MSRV retroviral particles has been evaluated in a hybrid animal model: severe combined immunodeficiency (SCID) mice grafted with human lymphocytes and injected intraperitoneally with MSRV virion or mock controls. MSRV-injected mice presented with acute neurological symptoms and died within 5 to 10 days post injection. Necropsy revealed disseminated and major brain hemorrhages, whereas control animals did not show abnormalities (P <.001). In ill animals, reverse transcriptase-polymerase chain reaction (RT-PCR) analyses showed circulating MSRV RNA in serum, whereas overexpression of proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma was evidenced in spleen RNA. Neuropathological examination confirmed that hemorrhages occurred prior to death in multifocal areas of brain parenchyma and meninges. Further series addressed the question of immune-mediated pathogenicity, by inoculating virion to SCID mice grafted with total and T lymphocyte-depleted cells in parallel: dramatic and statistically significant reduction in the number of affected mice was observed in T-depleted series (P <.001). This in vivo study suggests that MSRV retroviral particles from MS cultures have potent immunopathogenic properties mediated by T cells compatible with the previously reported superantigen activity in vitro, which appear to be mediated by an overexpression of proinflammatory cytokines.


Assuntos
Hemorragia Cerebral/virologia , Retrovirus Endógenos/isolamento & purificação , Esclerose Múltipla/virologia , Linfócitos T/virologia , Animais , Linfócitos B/citologia , Linfócitos B/virologia , Barreira Hematoencefálica/imunologia , Morte Celular/imunologia , Células Cultivadas , Hemorragia Cerebral/imunologia , Plexo Corióideo/citologia , Plexo Corióideo/virologia , Citocinas/genética , Modelos Animais de Doenças , Retrovirus Endógenos/patogenicidade , Expressão Gênica , Humanos , Camundongos , Camundongos SCID , Esclerose Múltipla/imunologia , Baço/fisiologia , Baço/virologia , Superantígenos/imunologia , Linfócitos T/citologia , Vírion , Virulência
7.
Virology ; 287(2): 321-32, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11531410

RESUMO

A retroviral element (MSRV) defining a family of genetically inherited endogenous retroviruses (HERV-W) has recently been characterized in cell cultures from patients with multiple sclerosis (MS). To address the possible relationship with MS, direct detection of circulating virion RNA was proposed but revealed technically difficult to perform in standardized conditions, in the face of multiple endogenous HERV-W copies. A parallel approach has evaluated MSRV potential pathogenicity in relation to characteristic features of multiple sclerosis, in particular, T-lymphocyte-mediated immunopathology. We report here that MSRV particles induce T-lymphocyte response with a bias in the Vbeta16 chain usage in surface receptor, whatever the HLA DR of the donor. A recombinant MSRV envelope-but not core-protein reproduced similar nonconventional activation. Molecular analysis of Vbeta CDR3 showed that Vbeta16 expansions are polyclonal. Our results thus provide evidence that MSRV envelope protein can trigger an abnormal immune response with similar characteristics to that of superantigens.


Assuntos
Retrovirus Endógenos/imunologia , Ativação Linfocitária/imunologia , Esclerose Múltipla/virologia , Infecções por Retroviridae/imunologia , Linfócitos T/imunologia , Proteínas do Envelope Viral/imunologia , Antígenos Virais/imunologia , Células Cultivadas , Citocinas/metabolismo , Retrovirus Endógenos/genética , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Esclerose Múltipla/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Proteínas Recombinantes/imunologia , Infecções por Retroviridae/virologia , Linfócitos T/metabolismo , Células Tumorais Cultivadas , Vírion/imunologia
8.
J Mol Biol ; 311(1): 217-28, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11469870

RESUMO

Herpesvirus proteases are essential for the production of progeny virus. They cleave the assembly protein that fills the immature capsid in order to make place for the viral DNA. The recombinant protease of the human gamma-herpesvirus Epstein-Barr virus (EBV) was expressed in Escherichia coli and purified. Circular dichroism indicated that the protein was properly folded with a secondary structure content similar to that of other herpesvirus proteases. Gel filtration and sedimentation analysis indicated a fast monomer-dimer equilibrium of the protease with a K(d) of about 60 microM. This value was not influenced by glycerol but was lowered to 1.7 microM in the presence of 0.5 M sodium citrate. We also developed an HPLC-based enzymatic assay using a 20 amino acid residue synthetic peptide substrate derived from one of the viral target sequences for the protease. We found that conditions that stabilised the dimer also led to a higher enzymatic activity. Through sequential deletion of amino acid residues from either side of the cleavage site, the minimal peptide substrate for the protease was determined as P5-P2'. This minimal sequence is shorter than that for other herpesvirus proteases. The implications of our findings are discussed with reference to the viral life-cycle. These results are the first ever published on the EBV protease and represent a first step towards the development of protease inhibitors.


Assuntos
Endopeptidases/química , Endopeptidases/metabolismo , Herpesvirus Humano 4/enzimologia , Sequência de Aminoácidos , Antivirais/química , Antivirais/metabolismo , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Dimerização , Endopeptidases/isolamento & purificação , Estabilidade Enzimática/efeitos dos fármacos , Glicerol/farmacologia , Herpesvirus Humano 4/crescimento & desenvolvimento , Cinética , Espectrometria de Massas , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Sais/farmacologia , Deleção de Sequência , Relação Estrutura-Atividade , Especificidade por Substrato , Temperatura , Termodinâmica , Ultracentrifugação
9.
Br J Cancer ; 84(6): 783-90, 2001 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-11259092

RESUMO

Since the few data exploring a possible association between Epstein-Barr virus (EBV) and breast cancer are conflicting, we investigated this association together with the influences of geographical areas. 509 breast cancers were sampled from areas with varying risks of nasopharynx carcinoma (NPC) such as North Africa (Algeria and Tunisia, high-risk area); southern France (Marseille, intermediate-risk area); and northern Europe (northern France, the Netherlands and Denmark; low-risk areas). Polymerase chain reaction (PCR) of a subregion of EBV BamHIC encoding the EBERs demonstrated that 31.8% of the tumours contained the viral genome. No significant differences were observed among the geographical areas. However, positive samples showed higher loads of the EBV genome in the NPC high- and intermediate-risk areas than in the low-risk areas. EBV type 1 was the dominant strain. In situ hybridization studies using a(35)S-labelled riboprobe for EBER1 and a laser capture microdissection, combined with quantitative PCR, showed that EBV localization was restricted to some tumour epithelial cell clusters. EBV could not be detected in the stroma. Considering the whole population covered, the presence of the EBV genome was not correlated with age, menopausal status, tumour, size, nodal status or histological grade.


Assuntos
Neoplasias da Mama/virologia , Carcinoma Ductal de Mama/virologia , Genoma Viral , Herpesvirus Humano 4/isolamento & purificação , Adulto , África do Norte , Sequência de Bases , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Primers do DNA , Europa (Continente) , Feminino , Herpesvirus Humano 4/genética , Humanos , Hibridização In Situ , Lasers , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos
10.
Blood ; 97(6): 1590-7, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11238096

RESUMO

Severe T-cell immunodeficiency after solid organ or bone marrow transplantation may result in the uncontrolled outgrowth of latently Epstein-Barr virus-infected B cells, leading to B-lymphoproliferative disorder (BLPD). Given the potentially important pathogenic role of IL-6 in BLPD, it was tested whether the in vivo neutralization of IL-6 by a monoclonal anti-IL-6 antibody could contribute to the control of BLPD. Safety and efficacy were assessed in 12 recipients of transplanted organs who had BLPD refractory to the reduction of immunosuppression over 8 days. Five patients received 0.4 mg/kg per day. The next 7 patients received 0.8 mg/kg per day. Treatment was scheduled to last 15 days. It was completed in 10 patients, and in the other 2 patients was discontinued early (days 10 and 13, respectively) because of disease progression. Treatment tolerance was good, and no major side effects were observed. High C-reactive protein levels were found in 9 patients before treatment but were normalized under treatment in all patients, demonstrating efficient IL-6 neutralization. Complete remission (CR) was observed in 5 patients and partial remission (PR) in 3 patients. Relapse was observed in 1 of these 8 patients in whom remission was observed. This relapse was unresponsive to treatment. Disease was stable in 1 patient, but it progressed in 3 patients. Seven patients are alive and well. Two patients died because of disease progression, and 3 patients died while in CR (chronic rejection in 2 patients and BLPD sequelae in 1 patient). These data suggest that the anti-IL-6 antibody is safe and should be further explored in the treatment of BLPD.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Linfócitos B/patologia , Interleucina-6/imunologia , Transtornos Linfoproliferativos/tratamento farmacológico , Adolescente , Adulto , Anticorpos Monoclonais/farmacocinética , Anticorpos Antivirais/sangue , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Feminino , Herpesvirus Humano 4/genética , Humanos , Lactente , Interleucina-6/sangue , Transtornos Linfoproliferativos/sangue , Transtornos Linfoproliferativos/etiologia , Masculino , Pessoa de Meia-Idade , Equivalência Terapêutica , Transplante de Tecidos/efeitos adversos , Resultado do Tratamento
11.
Clin Diagn Lab Immunol ; 8(2): 429-31, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238233

RESUMO

An easy, rapid, and reproducible test to distinguish residual cytomegalovirus (CMV) immunoglobulin M (IgM) antibodies from antibodies produced in primary infection could be useful, especially for pregnant women. The CMV avidity of IgG antibodies with the VIDAS automated enzyme-linked fluorescent assay and 6 M urea was evaluated in a multicenter study to differentiate between primary CMV infections and past infections or reactivations. A total of 416 serum specimens were tested: 159 specimens were from follow-up of primary infections, and 257 were from past infections. All of the specimens from primary infections collected within 4 months (17 weeks) after the onset of the infection had an avidity index lower than 0.8. An avidity index higher than 0.8 excludes a recent primary infection of less than 4 months. However, an avidity index higher than 0.8 cannot confirm all past infections, since 48 specimens (18%) from past infections had an avidity index lower than 0.8 (between 0.5 and 0.8). The exclusion capacity could be improved (96.9%) by using a cutoff of 0.7, but this index would decrease the specificity of the technique, since the avidity index was found to be between 0.7 and 0.8 in two patients with recent primary infection. All specimens from primary infections obtained more than 4 months after the onset of infection had an avidity index more than 0.2. In this study, an avidity index less than 0.2 confirms the presence of a recent primary infection of less than 4 months. The VIDAS CMV IgG avidity test is a rapid, reproducible test with very good performance.


Assuntos
Afinidade de Anticorpos , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Técnicas Imunoenzimáticas/métodos , Imunoglobulina G/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Estudos de Avaliação como Assunto , Feminino , Humanos , Técnicas Imunoenzimáticas/normas , Imunoglobulina G/sangue , Cinética , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Reprodutibilidade dos Testes
12.
Rheumatology (Oxford) ; 39(9): 950-4, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10986298

RESUMO

OBJECTIVES: To determine whether the recently identified multiple sclerosis-associated retrovirus, MSRV, is detectable in the serum and synovial fluid of patients with rheumatoid arthritis (RA). METHODS: A reverse transcription-polymerase chain reaction (RT-PCR) assay was used to seek evidence of particle-associated MSRV/HERV-W RNA in the plasma and synovial fluid of patients with RA and controls. Stringent precautions were taken to avoid detection of contaminating human genomic DNA and cellular RNA sequences. RESULTS: Thirty-seven plasma samples were tested (20 from RA patients and 17 from controls) but none had detectable MSRV/HERV-W RNA. Synovial fluid samples were available from nine patients with RA and 10 controls. Particle-associated MSRV/HERV-W RNA was reproducibly detected in two of nine synovial fluid samples from RA patients and in one control sample. The identity of RT-PCR products was confirmed by sequencing. CONCLUSION: MSRV/HERV-W RNA sequences are detectable in the synovial fluid of a small proportion of RA patients, but this phenomenon may not be specific to RA.


Assuntos
Artrite Reumatoide/virologia , Esclerose Múltipla/virologia , RNA/análise , Retroviridae/genética , Líquido Sinovial/química , Humanos
13.
Microbes Infect ; 1(4): 309-22, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10602665

RESUMO

Publications describing retroviral sequences associated with extracellular particles in Sjögren's syndrome or systemic lupus erythematosus, multiple sclerosis, and type I diabetes present novel arguments and raise complex questions about eventual relationships between retroviruses and autoimmunity. They are presented and discussed in the present review, preceded by an overview of the biology of retroviral elements.


Assuntos
Doenças Autoimunes/virologia , Retrovirus Endógenos/fisiologia , Retroviridae/fisiologia , Animais , Artrite Reumatoide/virologia , Diabetes Mellitus Tipo 1/virologia , Retrovirus Endógenos/classificação , Retrovirus Endógenos/genética , Retrovirus Endógenos/isolamento & purificação , Evolução Molecular , Genoma Viral , Humanos , Lúpus Eritematoso Sistêmico/virologia , Esclerose Múltipla/virologia , Retroelementos , Retroviridae/classificação , Retroviridae/genética , Retroviridae/isolamento & purificação , Síndrome de Sjogren/virologia , Vírion/genética , Vírion/fisiologia
14.
J Clin Microbiol ; 37(8): 2709-14, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10405428

RESUMO

A new immunoblot assay, composed of four Epstein-Barr virus (EBV)-encoded recombinant proteins (virus capsid antigen [VCA] p23, early antigen [EA] p138, EA p54, and EBNA-1 p72), was compared with an immunofluorescence assay on a total of 291 sera. The test was accurate in 94.5% of cases of primary EBV infection, while an immunoglobulin G anti-VCA p23 band with strong intensity correlated with reactivation.


Assuntos
Antígenos Virais/imunologia , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/virologia , Herpesvirus Humano 4/isolamento & purificação , Immunoblotting/métodos , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/virologia , Antígenos Virais/análise , Herpesvirus Humano 4/imunologia , Humanos , Proteínas Recombinantes/análise , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Testes Sorológicos/métodos
15.
Leukemia ; 13(2): 298-301, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10025906

RESUMO

From the longitudinal study of a cohort of HIV-positive patients, we report the case of a patient who initially harbored the Epstein-Barr virus (EBV) type 1 and subsequently developed an EBV-2-associated non-Hodgkin's B lymphoma a few years after an EBV-2 reactivation, or an exogenous reactivation, in the blood. At the time of diagnosis of hepatic lymphoma, the blood and the throat harbored high levels of the EBV-1 dominant strain. Sequence analysis of EBNA-2 gene revealed that: (1) type 2 EBV detected during reactivation and then in hepatic tumor was very likely to be the same strain and was mostly identical to the EBV prototype AG876; (2) type 1 virus conserved the same mutations during all the follow-up. These results suggest that EBV-2 might be associated with lymphomatogenesis and that a transient reactivation could lead to the development of an EBV-associated disease.


Assuntos
Herpesvirus Humano 4/isolamento & purificação , Neoplasias Hepáticas/virologia , Linfoma Relacionado a AIDS/virologia , Genótipo , Humanos , Masculino , Mutação , Carga Viral
16.
Rev Prat ; 49(20): 2217-21, 1999 Dec 15.
Artigo em Francês | MEDLINE | ID: mdl-10731805

RESUMO

Epstein-Barr virus (EBV) is a B-lymphotropic human herpesvirus that infects the vast majority of the world's population; it establishes lifelong latency in the infected host. The virus enters through the oropharyngeal mucus and replicates in epithelial cells. The infiltrating B lymphocytes become infected and normal resting B cells activated by the virus result in immortalised B cell populations. This growth program utilises all of the latent genes and proteins. Following primary infection, the virus is found in saliva for weeks and chronic shedding participates in transmitting the infection from person to person through intimate kissing contact. EBV causes infectious mononucleosis, leads to EBV-induced malignant B-cell lymphoma in immunosuppressed patients, and is implicated in the pathogenesis of several cancers in the immunocompetent. Laboratory confirmation of infectious mononucleosis employing serological testing is generally required. Chronic infection and reactivation however need additional investigations such as nucleic acids testing. Quantitative polymerase chain reaction is now used as the major marker in B-cell proliferations either for assessing risk factors or for evaluating the efficacy of anti-EBV treatments.


Assuntos
Linfoma de Burkitt/virologia , Herpesvirus Humano 4/patogenicidade , Mononucleose Infecciosa/virologia , Linfoma de Células B/virologia , Antivirais/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/patologia , Sobrevivência Celular , Diagnóstico Diferencial , Humanos , Mononucleose Infecciosa/tratamento farmacológico , Mononucleose Infecciosa/patologia , Linfoma de Células B/patologia
17.
Leuk Lymphoma ; 35(3-4): 379-87, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10706463

RESUMO

Human Herpesvirus 8 (HHV-8) has been consistently associated with Primary Effusion Lymphoma (PEL or body-cavity-based lymphoma) but not with other lymphomas. This paper reports on an AIDS patient without obvious malignant effusion in body cavities but with a cutaneous lymphoma where HHV-8 and Epstein-Barr virus (EBV) were detected by PCR and electron microscopy. Both viruses were also detected in all the cells of a malignant cell line (BBG1) established from the patient's peripheral blood mononuclear cells. As in PEL and PEL-derived cell lines, both the tumor and the lines lacked B-antigen expression in immunological studies but were of the same B origin as shown by clonal immunoglobulin gene rearrangements. In contrast to other co-infected cell lines, BBG1 and subclones spontaneously expressed the HHV-8 lytic antigens p40, p27, p60 and the EBV transforming latent antigen EBNA2. These data suggest that the clinical and biological features of HHV-8-and EBV-associated lymphomas could be wider than has been described to date in PEL particularly with the in vivo presence of circulating malignant dually-infected cells engaged in a spontaneous HHV-8 lytic infection.


Assuntos
Síndrome da Imunodeficiência Adquirida/virologia , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 8/isolamento & purificação , Linfoma de Células B/virologia , Linfoma/virologia , Neoplasias Cutâneas/virologia , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/patologia , Humanos , Linfoma/etiologia , Linfoma de Células B/etiologia , Dados de Sequência Molecular , Neoplasias Cutâneas/etiologia , Células Tumorais Cultivadas
18.
Hepatology ; 28(6): 1680-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9828235

RESUMO

We studied the efficacy of three interferon alfa-2b (IFN-2b) regimens for the retreatment of patients with chronic hepatitis C (CHC) with prior complete response followed by relapse. Consecutive patients with CHC who had a complete biochemical response but relapse after a first course of 6 months of IFN with 3 million units (MU) given subcutaneously three times per week were enrolled in the study. Six to 24 months after the end of the first treatment, the patients were randomly assigned to receive IFN with either the same regimen (group 1), a regimen of 12 months with 3 MU (group 2), or a regimen of 6 months with 10 MU (group 3). Sustained biochemical response was defined as normal serum alanine transaminase (ALT) values during the follow-up and sustained virological response as a clearance of hepatitis C virus (HCV) RNA from the serum at the end of follow-up (6 months' posttreatment). Histological improvement was defined as a decrease of 1 point in Metavir score between the first liver biopsy and a biopsy performed at 6 months' postretreatment. Two hundred forty-seven patients were randomized: 75 to group 1, 91 to group 2, and 81 to group 3. In an intent-to-treat analysis, 12%, 36.3%, and 18.5% of patients had a sustained biochemical response after retreatment in groups 1, 2, and 3, respectively (P <.001); 13. 8%, 32.4%, and 17.2% of patients had a sustained virological response after retreatment in groups 1, 2, and 3, respectively (P <. 05). A low viral load and patients in group 2 were independently associated with a sustained biochemical response. A low Knodell score index before treatment, patients with a high level of ALT before retreatment, genotype 3, low viral load, and patients in group 2 were independently associated with sustained virological response. Younger age, a high level of ALT, a low level of gamma-glutamyl transferase before retreatment, low viral load, and patients in group 2 were independently associated with sustained biochemical and virological response. Among the 80 patients with repeated liver biopsies, 47.6% had improved histological activity scores; this improvement was associated with a sustained biochemical and virological response. In patients with CHC initially treated with 3 MU of IFN given subcutaneously three times per week over a 6-month period, and who subsequently developed a relapse after a biochemical response, retreatment with a regimen of 3 MU of IFN given three times per week for 12 months produced better biochemical and virological sustained response rates than regimens involving a higher dose or a shorter duration of retreatment. The biochemical and virological sustained response was associated with histological improvement.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/terapia , Interferon-alfa/administração & dosagem , Adulto , Alanina Transaminase/sangue , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Esquema de Medicação , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/metabolismo , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Recombinantes , Recidiva , Retratamento , Carga Viral
19.
Int J Cancer ; 77(2): 205-10, 1998 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-9650553

RESUMO

In a previous study of Epstein-Barr virus (EBV) strains in North African nasopharyngeal carcinoma (N PC) biopsies, we have found that the viral strain present was of A/F/W'-I'/Xhol kept/H1-H2 type, while the strain associated with Chinese NPC was the A/"f"/W'I'/Xhol lost/H type. Using the restriction fragment length polymorphism (RFLP) and PCR-RFLP methods, the present study analyzed the H1-H2 variant in different clinical samples from Algeria, including the saliva of healthy EBV-positive individuals and patients with NPC or Hodgkin's disease (HD), as well as HD biopsies and lymphoblastoid cell lines (LCLs) established from the oropharyngeal virus-infected cells. Our results demonstrate that, in contrast to the H1-H2 variant found in NPC biopsies, the H genotype was dominant in HD biopsies. Moreover, H genotype was also dominant in the oropharynx of healthy EBV-positive individuals, of patients with NPC and with HD. Our results clearly indicate that in North Africa the EBV strain present of NPC biopsies is different from that shed in the oropharynx. This may suggest a specific distribution of the H1-H2 variant in the NPC epithelial tumor, whereas the H genotype is dominant in HD biopsies and in the oropharynx. The specific association of both viral strains with these 2 distinct diseases in North Africa may reflect a difference in tumorigenicity.


Assuntos
Herpesvirus Humano 4/genética , Doença de Hodgkin/virologia , Neoplasias Nasofaríngeas/virologia , Orofaringe/virologia , Argélia , Anticorpos Antivirais/análise , Biópsia , Células Cultivadas , Variação Genética , Herpesvirus Humano 4/imunologia , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Saliva/virologia
20.
J Hepatol ; 28(1): 27-33, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9537860

RESUMO

BACKGROUND/AIMS: The purpose of this study was to compare the epidemiological, biochemical, virological and histological characteristics of patients with chronic hepatitis B and C with those of patients suffering from chronic hepatitis C alone. METHODS: Twenty-three patients with chronic hepatitis C, who were anti-HCV positive and HBs antigen positive, were studied and subdivided into two groups according to the presence or absence of HBV DNA replication. They were compared to 69 age- and sex-matched patients with chronic hepatitis who were anti-HCV positive and HBs antigen negative. All patients were HCV RNA positive by PCR, anti-HIV negative and anti-HDV negative. HBV DNA and HCV RNA were detected in serum by means of a branched DNA assay and PCR. The HCV serotypes were determined by the Chiron Riba HCV serotyping SIA technique. The histological characteristics included the Knodell score. RESULTS: Epidemiological, biochemical and virological parameters were not different between the two groups. Only the prevalence of cirrhosis was greater in chronic hepatitis B and C patients than in patients with chronic hepatitis C alone (p = 0.01). Among chronic hepatitis B and C patients, HCV RNA level was significantly lower in HBV DNA positive than in HBV DNA negative patients (p = 0.01). Indeed, histological lesions were more severe in HBV DNA positive than in HBV DNA negative patients, including prevalence of cirrhosis (p = 0.01), Knodell score (p = 0.05) and, among the latter, piecemeal necrosis (p = 0.01) and fibrosis (p = 0.05). The characteristics of patients with dual infection did not differ according to the mode of contamination and duration of HBV disease, except for a shorter duration in patients contaminated by drug abuse than in other patients. CONCLUSIONS: These results suggest that HBV DNA replication inhibits HCV RNA replication in patients with chronic active hepatitis B and C but increases the severity of histological lesions.


Assuntos
Hepatite B/complicações , Hepatite C/complicações , Adulto , Biópsia por Agulha , Transfusão de Sangue , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Hepacivirus/isolamento & purificação , Hepatite B/epidemiologia , Hepatite B/patologia , Hepatite B/fisiopatologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite C/epidemiologia , Hepatite C/patologia , Hepatite C/fisiopatologia , Humanos , Fígado/patologia , Testes de Função Hepática , Masculino , Reação em Cadeia da Polimerase , RNA Viral/análise , Transtornos Relacionados ao Uso de Substâncias
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