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1.
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
2.
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
3.
J Gen Virol ; 75 ( Pt 2): 431-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8113767

RESUMO

Two types of Epstein-Barr virus (EBV), EBV-1 and EBV-2, were identified on the basis of DNA sequence divergence in the genes for nuclear proteins EBNA 2, 3a, 3b and 3c. In the present study, we conducted an immunological and genomic analysis in a human immunodeficiency virus (HIV)-infected population to determine the prevalence of the two types, and whether the identified type was stable over years. The EBNA-2 serotyping and genotyping showed that HIV-infected patients were highly infected by EBV-2, and that the dominant strain was mostly retained. However, during a follow-up study, a change in the dominant viral strain was observed in two patients. A first HIV-positive patient (patient A), although having a stable level of anti-EBNA-2A and -2B antibodies, showed a change in the genotype and antigen produced in spontaneously established lymphoblastoid cell lines (LCL). The sequence analysis of LCLs confirmed the emergence of the EBV-2 type population. A strain from a second HIV-positive patient (patient B) was clearly identified as EBV-2: the genotype from a saliva sample and from sequential LCLs belonged to EBV-2, as well as the antigen produced from LCLs, and serum antibodies. After a 5-year continuous EBV-2 infection, a reactivation of the EBV-1 strain was observed. In both cases, sequence analysis of the EBNA-2 gene showed, only with EBV-1, the presence of EBV variants related to the B95-8 prototype. Two mutations (at nucleotides 49212 and 49304) were found in both patients A and B, whereas an additional mutation (at nucleotide 49237) was characteristic of the patient A. No mutation relative to the prototype B95-8 strain was observed in a subsequent analysis of this EBNA-2 region from LCLs obtained from two HIV-negative patients predominantly infected by EBV-1. Therefore, we speculate that these mutations may be EBV-1 mutations specifically occurring during HIV infection.


Assuntos
Infecções por HIV/microbiologia , Herpesvirus Humano 4/classificação , Antígenos Virais/genética , Antígenos Virais/imunologia , Sequência de Bases , DNA Viral/análise , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Antígenos Nucleares do Vírus Epstein-Barr , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Humanos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase
4.
Blood ; 71(3): 581-5, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2830925

RESUMO

Recent studies have shown that autoreactive B cells and autoantibodies are present in pathological as well as in normal situations. In the present study, we immortalized human B cell lines from normal individuals and from patients with malignant or benign dysglobulinemia with Epstein-Barr virus and examined, after cloning, the autoantibody reactivities of the immunoglobulins secreted by these cells. Forty-two supernatants were analyzed by enzyme-immunoassay on a panel of 13 self and non-self antigens: trinitrobenzenesulfonic acid (TNP), DNA, L-glutamine, L-alanine, L-tyrosine (GAT), actin, myosin, tubulin, albumin, renin, spectrin, transferrin, thyroglobulin, myoglobin, peroxidase, and by immunofluorescence in tissue sections. Fourteen (33%) of the immunoglobulin-secreting cell lines were found to have an autoantibody function; seven secreted IgM, six IgA, and one IgG. The light chains were of the kappa type in 11 cases. The vast majority of these clones reacted with more than five antigens of the panel and all of them reacted with TNP. No correlation was found between a given isotype and an antibody specificity. More than half of these antibodies also reacted with cellular antigens present in tissue sections. None of the four cell lines secreting monoclonal antiviral antibodies reacted with any of the antigens of the panel. The results indicate that immunoglobulins secreted by human monoclonal lymphoid cell lines can have polyspecific autoantibody functions, similar to those found in normal human polyclonal antibodies, in human monoclonal paraproteins and in natural monoclonal antibodies synthesized by murine or rat clones obtained from physiologically normal animals.


Assuntos
Anticorpos/imunologia , Autoanticorpos/imunologia , Transformação Celular Viral , Herpesvirus Humano 4 , Linfócitos/imunologia , Anticorpos Anti-Idiotípicos/imunologia , Especificidade de Anticorpos , Linhagem Celular , Humanos , Imunoglobulina M/imunologia
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