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1/21. Characterization of Epstein-Barr virus (EBV)-infected natural killer (NK) cell proliferation in patients with severe mosquito allergy; establishment of an IL-2-dependent NK-like cell line.

    The clinical evidence of a relationship between severe hypersensitivity to mosquito bite (HMB) and clonal expansion of EBV-infected NK cells has been accumulated. In order to clarify the mechanism of EBV-induced NK cell proliferation and its relationship with high incidence of leukaemias or lymphomas in HMB patients, we studied clonally expanded NK cells from three HMB patients and succeeded in establishing an EBV-infected NK-like cell line designated KAI3. immunoblotting and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses revealed that KAI3 cells as well as infected NK cells exhibited an EBV latent infection type II, where EBV gene expression was limited to EBNA 1 and LMP1. As KAI3 was established by culture with IL-2, IL-2 responsiveness of peripheral blood NK cells from patients was examined. The results represented markedly augmented IL-2-induced IL-2R alpha expression in NK cells. This characteristic property may contribute to the persistent expansion of infected NK cells. However, KAI3 cells as well as the NK cells from patients were not protected from apoptosis induced by either an anti-Fas antibody or NK-sensitive k562 cells. Preserved sensitivity to apoptosis might explain the relatively regulated NK cell numbers in the peripheral blood of the patients. To our knowledge, KAI3 is the first reported NK-like cell line established from patients of severe chronic active EBV infection (SCAEBV) before the onset of leukaemias or lymphomas. KAI3 cells will contribute to the study of EBV persistency in the NK cell environment and its relationship with high incidence of leukaemias or lymphomas in HMB patients.
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keywords = lymphoma
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2/21. Virological and molecular characterisation of a new B lymphoid cell line, established from an AIDS patient with primary effusion lymphoma, harbouring both KSHV/HHV8 and EBV viruses.

    We report here a new case of primary effusion lymphoma (PEL), occurring in a French homosexual hiv-1 infected male with a pericardial, pleural and mesenteric tumour dissemination, and the establishment from his pleural effusion of a new cell line, Cra-BCBL, dually infected by EBV and KSHV/HHV8. Cra-BCBL cells are of B-cell origin as judged by their clonal immunoglobulin heavy chain (IgH) gene rearrangement, identical to that of the parental tumour. Both the cell line and the lymphoma cells expressed CD38 and CD45 antigens but no classical B-cell or T-cell lineage-restricted antigens. Cra-BCBL harbours a type I EBV virus, expressing a latency type II. Expression of KSHV/HHV8 ORF72 and ORF75 was detected by RT/PCR. In addition, KSHV lytic replication could be induced by treatment by n-butyrate. An equivalent and high copy number of KSHV genomes (20 to 200 copies by cell) was detected both in the primary tumour cells and in the cell line. Southern blot (SB) analysis of EBV terminal repeats (TR) displayed the same unique band in the cell line dna and in the original tumour cells, consistent with a monoclonal infection of EBV. Furthermore, SB analysis of KSHV/HHV8 TR revealed the same hybridisation pattern between Cra-BCBL and the effusion cells, with a common band at around 30-40 kb corresponding to the fused termini of the viral episomes and a 5 Kb rearranged fragment. The new cell line characterised here could be a useful model to study interactions between two human herpes viruses and their contribution to lymphomagenesis.
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ranking = 2.3333333333333
keywords = lymphoma
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3/21. Epstein-Barr virus-associated high-grade B-cell lymphoma of mucosal-associated lymphoid tissue in a 9-year-old Boy.

    We report an unusual case of Epstein-Barr virus (EBV)-associated mucosal-associated lymphoid tissue (MALT) lymphoma involving the lungs, kidneys, and axillary lymph nodes in a child with congenital hypoadrenalism and panhypopituitarism. The patient presented with an aggressive clinical course and histologic evolution. Initial biopsies (1994) of the lung and kidney revealed histologic features of low-grade B-cell MALT lymphoma with lymphoepithelial lesions within the renal tubules and bronchial epithelium. Subsequent biopsies (1996, 1997, and 1999) revealed progressively greater cytologic atypia, polymorphism, and necrosis; an increased mitotic rate; and a preponderance of large cells, indicative of progression from a low-grade to a high-grade MALT lymphoma. immunophenotyping of the lung and lymph node lesions revealed identical surface marker profiles: cells were CD19( ), CD20( ), immunoglobulin (Ig) G( ), kappa( ), lambda(-), CD5(-), CD10(-), CD23(-), and IgM(-), and also negative for T-cell markers. Genotypic analysis demonstrated the presence of immunoglobulin heavy chain rearrangement and monoclonality of EBV in the lung lesion by Southern blot hybridization and polymerase chain re()action (PCR). The clinicopathologic features suggest that these lesions might represent an immunosupression-related continuum of low-grade to high-grade MALT lymphomas. infection with EBV may have contributed to this tumor's aggressive clinical and histologic evolution.
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ranking = 2.6666666666667
keywords = lymphoma
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4/21. Establishment and comprehensive analysis of a new human transformed follicular lymphoma B cell line, Tat-1.

    A spontaneously EBV transformed follicular lymphoma (FL) cell line, Tat-1, was established from the lymph node biopsy specimen of a patient with B cell FL, grade 1 in transformation to high grade disease. Tat-1 cells expressed lymphoid markers and developed tumor masses in immunodeficient mice. Bcl-2, Bcl-X(L), Bax and p53 protein expression was revealed by Western blotting. Flow cytometric analysis confirmed P-gp expression. Cytogenetically, the Tat-1 cell line showed identical chromosomal alterations to that of the initial biopsy specimen, among which the most notable were the t(14;18) typical of FL and additional abnormalities involving chromosomes 1, 8 and 13. Multicolor FISH analysis delineated all abnormalities, including a t(1p;8q), a der(8)(8q24::14q32::18q21) and a der(13)(13q32::8q24::14q32::18q21). Further FISH investigations using a locus-specific probe cocktail containing c-myc, IgH and bcl-2 revealed fusion of these three loci on the derivatives 8 and 13, in addition to the derivative 14 IgH/bcl-2 fusion and an extra copy of c-myc on derivative chromosome 1. These results demonstrate an additional example of the deregulation of bcl-2 and c-myc expression through recombination with a single IgH enhancer region. The unusual molecular features of the Tat-1 cell line render it a unique tool for studies focused on cytogenetic alterations, expression of multidrug resistance phenotype and expression of anti-apoptotic proteins in FL.
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ranking = 1.6666666666667
keywords = lymphoma
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5/21. acquired immunodeficiency syndrome-associated T-cell lymphoma: evidence for human immunodeficiency virus type 1-associated T-cell transformation.

    The majority of lymphomas in the setting of acquired, iatrogenic, or congenital immunodeficiencies are B-cell lymphoproliferations. We describe a rare T-cell lymphoma in a fulminantly ill patient infected with human immunodeficiency virus type 1 (hiv-1). The T-cell nature of the process was defined genotypically (monoclonal T-cell receptor beta-chain [CT beta] rearrangement) and phenotypically (CD45RO , CD4 , CD5 , CD25 , CD8-, CD3- and negative for a variety of B-cell and monocyte markers). The CD4 , CD25 (interleukin-2 receptor [IL-2R]) phenotype with production of IL-2 and IL-2R rna is analogous to human T-lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia/lymphoma (ATLL); however, no HTLV-1 could be detected. Southern blot analysis did demonstrate monoclonally integrated hiv-1 within the tumor genome. Furthermore, the tumor cells were producing HIV p24 antigen as shown by immunohistochemistry. This is the first case of acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin's lymphoma in which hiv-1 infection may have played a central role in the lymphocyte transformation process.
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ranking = 2.6666666666667
keywords = lymphoma
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6/21. Successful control of Epstein-Barr virus (EBV)-infected cells by allogeneic nonmyeloablative stem cell transplantation in a patient with the lethal form of chronic active EBV infection.

    Chronic active Epstein-Barr virus infection (CAEBV) is a heterogeneous EBV-related disorder, ranging from mild/moderate forms to rapidly lethal disorders. The lethal form of CAEBV is characterized by multiple organ failure, hemophagocytic syndrome, and development of lymphomas. Allogeneic stem cell transplantation is considered as the only potentially curative treatment for the lethal form of CAEBV, but it is not always desirable because of the high incidence of regimen-related toxicities. A 17-year-old female with CAEBV, who was refractory to conventional therapies and considered to be unable to receive a myeloablative regimen because of multiple organ dysfunction, underwent allogeneic nonmyeloablative stem cell transplantation (allo-NST) before developing a hematological malignancy. She has been well without any signs of CAEBV for 27 months after allo-NST, and we confirmed that specific cytotoxic T lymphocyte activity against EBV was reconstituted. This outcome suggests that allo-NST can control CAEBV by reconstituting the host immunity against EBV.
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ranking = 0.33333333333333
keywords = lymphoma
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7/21. Burkitt transformation of mantle cell lymphoma.

    The associated poor prognosis and potentially aggressive behavior of mantle cell lymphoma and its blastoid variants make differentiation from other non-Hodgkin B-cell lymphomas especially important. We present a case of mantle cell lymphoma with a marked leukemic component, which demonstrated both a typical nodular mantle cell pattern and burkitt lymphoma within a single lymph node removed at the time of splenectomy. The presence of CD5, CD10, and Bcl-1 co-expression by immunohistochemistry and detectable t(11;14) and cMYC gene rearrangement by FISH analyses in the Burkitt region support a transformation of mantle cell lymphoma over a concomitant malignancy. A limited number of mantle cell lymphomas demonstrating dual t(11;14) and chromosome 8q24 cMYC gene rearrangements have been previously reported in the literature. They demonstrate an extremely aggressive course with a very poor prognosis. Although the accelerated terminal phase of this patient's clinical course mirrors these previous published cases; none have described the combined morphologic and immunophenotypic features of burkitt lymphoma reported here. This case provides further support for the aggressive nature of these lymphomas and demonstrates the utility of flow cytometry, immunohistochemistry, and cytogenetic techniques in avoiding potential errors in their diagnosis, prognosis, and treatment.
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ranking = 4
keywords = lymphoma
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8/21. Follicular lymphoid hyperplasia of the oral cavity representing progressive transformation of germinal center.

    Follicular lymphoid hyperplasia (FLH) of the oral cavity is a rare and poorly understood lymphoproliferative disorder. We present a case of FLH of the oral cavity presenting with progressive transformation of germinal center (PTGC). The patient was a 49-year-old Japanese woman presenting with a hard mass in the right cheek. The resected specimen contained numerous lymphoid follicles with active germinal centers and a portion of the lymphoid follicles exhibited PTGC. The PTGCs contained a few large lymphoid cells resembling lymphocytic and histiocytic reed-sternberg cells of nodular lymphocyte-predominant Hodgkin lymphoma. The PTGC was surrounded by groups of epithelioid cells. in situ hybridization studies demonstrated strong expression of Epstein-Barr virus (EBV)-encoded small rna in scattered large lymphoid cells in the PTGC. Although the etiology of FLH of the oral cavity remains unclear, the present case suggests that a subset of FLH of the oral cavity appears to be an EBV-associated lymphoproliferative disorder.
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ranking = 0.33333333333333
keywords = lymphoma
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9/21. Viral attributes and host factors in carcinogenesis: herpesviruses.

    This paper describes two different experiments of nature: 1) the persistence of unusual virus strains of Epstein-Barr virus (EBV) (which proved oncogenic in vitro) and cytomegalovirus (CMV) in lymphoid cells following congenital or early acquired infection; 2) the occurence of multiple cases of Burkitt's lymphoma and nasopharyngeal carcinoma in one family. All the members of this family were EBV viral capsid antigen (VCA) and nuclear antigen (EBNA) antibody positive. The two patients with nasopharyngeal carcinoma had high titers of EBV-VCA, EA, and EBNA antibodies. The only member of this family having EBV early antigen (EA antibodies in addition to the patients with tumors was the mother. Borderline iga deficiency was documented in 3 members of this family. These findings illustrate the importance of host factors (intracellular resistance to transformation and secondarily, immunological surveillance) in the outcome of the host-virus challenge whether cancer or infectious disease is the outcome. Extensive studies of these cases may provide the best insight into the mysteries of viral oncogenesis.
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ranking = 0.33333333333333
keywords = lymphoma
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10/21. Transformation of hairy cell leukemia to EBV genome-containing aggressive B cell lymphoma.

    Hairy cell leukemia is a preplasmacytic B cell leukemia which is not EBV associated, although elevated titers of Epstein-Barr virus (EBV) antibodies have been seen in this leukemia and chronic lymphocytic leukemia. Hairy cells are not readily susceptible to EBV infection in vitro, even though they are EBV receptor-positive B cells. We have observed a 59-year-old patient who after 9 years of hairy cell leukemia developed a well-differentiated IgG-kappa monoclonal B cell lymphoma without further evidence of hairy cell leukemia. Pathologically, the lymphoma showed plasmacytic differentiation, and in the patient's serum, a 2 g/dl monoclonal IgG-kappa component was present. dna extracted from the lymphomatous lymph node hybridized with dna fragments of a reiterated sequence of EBV, IR1. The transformation, with no chemotherapy involved, from a preplasmacytic leukemia into a lymphoplasmacytic lymphoma with monoclonal gammopathy may be related to the entry of EBV into these cells. Studies at the molecular level may help understand mechanisms of malignant transformation or interconversion in lymphoproliferative disorders of the B cell type.
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ranking = 2.6666666666667
keywords = lymphoma
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