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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epstein-Barr virus (EBV) infects virtually everyone by adulthood, and a lifelong latency is maintained. It infects children silently, whereas the majority of adolescents have infectious mononucleosis (IM). Children who have IM before 5 years of age are often heterophil negative; EBV-specific antibodies are required for diagnosis. On rare occasions the symptoms of IM may persist in a chronic or recurrent form, and fatal infectious mononucleosis occurs rarely. Depending on the type and degree of immune deficiency and the time the EBV infection occurs in the life cycle, various atypical outcomes can occur. Children with primary immune deficiency can have fatal or chronic IM, malignant B cell lymphoma, virus-associated hemophagocytic syndrome, aplastic anemia, or acquired hypogammaglobulinemia. The various outcomes of the EBV infections are likely governed by the immune response of the individual. The increased frequency of B cell neoplasms in immunodeficient patients is likely due, in part, to EBV. Individuals with acquired immune deficiency disorders such as AIDS or allograft recipients may develop malignant B cell lymphomas which tend to be polyclonal, but which may progress through stages of oligoclonality to monoclonality. This conversion likely results from specific reciprocal chromosomal translocations such as t(8;14), which is seen in Burkitt's lymphoma. Detection of EBV in immunodeficient patients is achieved by EBV-specific antibody studies or isolation of virus by obtaining spontaneous lymphoblastoid cell lines from peripheral blood, isolating virus from throat washings, or identifying EBV genome by molecular hybridization techniques. Prevention of primary immune deficiency by early detection and genetic counseling and monitoring of patients for occurrence of EBV infection may lead to early treatment. Acyclovir and immunoglobulin therapy can be of value in some patients with active EBV infection.
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PMID:Epstein-Barr virus: the spectrum of its manifestations in human beings. 303 69

Cells from human B cell lymphomas were analyzed by means of the fluorescence-activated cell sorter (FACS) according to the amount of kappa or lambda immunoglobulins (Ig) on their surface. The crucial requirements for sensitive recognition of small numbers of tumor cells admixed in a normal population are described. Tumor cells were identified as an excess of cells bearing one light chain type ('clonal excess') at discrete levels of fluorescence intensity. Normal patterns of fluorescence staining are compared to those for tissues infiltrated with tumor. For B cell neoplasms with surface Ig of weak intensity, such as chronic lymphocytic leukemia, as few as 1% of the tumor cells admixed with normal cells could be detected; the bright surface fluorescence of cells from lymphoma permitted their recognition when only 0.1% of the tumor cells were present. FACS analysis was carried out on the peripheral blood of a series of patients with B cell lymphoma whose blood was normal by classic cytologic and cytochemical analysis. Nevertheless, circulating tumor cells were recognized in the majority of cases, suggesting that 'subclinical leukemia' is a common finding in B cell lymphomas.
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PMID:Analysis and detection of B cell neoplasms. 678 56

By means of the clonotypic variable region, the immunoglobulin (Ig) is a tumor-specific antigen on B cell neoplasms. We report that engagement of the B cell antigen receptor (BcR) promotes presentation of peptides derived from the B cell's intrinsic Ig to major histocompatibility complex (MHC) class II-restricted T cells. Thus, anti-Ig endowed normal, ex vivo B lymphocytes from H-2d, Ig constant heavy chain allotype b (IgCHb) mice with the capacity to stimulate an I-Ad-restricted T cell clone which recognizes the gamma 2ab 435-451 allopeptide. The corresponding self gamma 2aa peptide is cryptic and 6000-fold less antigenic than the gamma 2ab allopeptide. Even so, the syngeneic B cell lymphoma A20 which expresses surface(s) IgG2aa, was also recognized by the T cells after BcR ligation. Thus, anti-Ig triggered the disclosure of a cryptic tumor antigen determinant. We propose that autoantigens, by engaging the BcR of self-reactive B cells, induce presentation of intrinsic Ig peptides to which the T helper cell (Th) repertoire is not tolerant. In this way, B cells with anti-self potential may be activated without Th recognition of nominal autoantigen.
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PMID:Engagement of the B lymphocyte antigen receptor induces presentation of intrinsic immunoglobulin peptides on major histocompatibility complex class II molecules. 917 1

The development of rapid polymerase chain reaction (PCR) protocols for amplification of rearranged heavy chain immunoglobulin (IgH) gene sequences has facilitated the identification of clonal IgH rearrangements in non-Hodgkin's lymphomas (NHL) and leukemias of B lineage. In the present report we have explored the recently described improved strategy for assessment of clonality of rearranged immunoglobulin heavy chain (IgH) genes in more detail in a series of 101 B cell malignancies and 50 polyclonal controls. The assay is based on an IgH-PCR with an automated fluorescence-based strategy for PCR detection of IgH gene rearrangements. Third complementarity determining region (IgH-CDR3) sequences were amplified using fluorescent dye labeled consensus primers homologous to the corresponding variable (V[H]) and joining (J[H]) gene segments in combination with a thermostable proofreading DNA polymerase. PCR products were size separated on a high resolution polyacrylamide gel and analyzed for clonality by exact size determination and fluorescence quantification in an automated DNA sequencer. PCR findings obtained with the optimized IgH-CDR3-PCR assay showed an overall monoclonality detection rate of 97% (97 of 101 cases with B cell neoplasms). The specificity was 100% as determined by analysis of 50 controls, all of which gave polyclonal PCR results. We found a high rate of monoclonal IgH-CDR3-PCR results not only in the leukemias and diffuse lymphoma but also in the group of follicular lymphoma, where a high rate of false negative results is frequently reported in the literature. In summary, we identified monoclonal IgH-CDR3 junctions in 55 out of 59 cases (93%) with B cell lymphoma and in 42 of 42 (100%) cases with leukemia, immunocytoma and multiple myeloma. The results demonstrate that automated fluorescence detection of IgH-CDR3-PCR products is an ideal tool for detection of clonal and polyclonal lymphoid B cells. In combination with allele-specific primers the procedure may improve current experimental approaches to detect occult malginant B cells during initial staging and follow-up of NHL and ALL patients.
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PMID:Automated high resolution PCR fragment analysis for identification of clonally rearranged immunoglobulin heavy chain genes. 920 91

Mantle cell lymphomas comprise 2 to 8% of non-Hodgkin's lymphoma in the United States. They occur in older adults with a distinct male predominance, who present with generalized lymphadenopathy, and often have disseminated disease at the time of diagnosis. Pathologically, mantle cell lymphomas are characterized by a proliferation of small lymphocytes, with irregular nuclei, clumped chromatin, and sparse cytoplasm that can grow in nodular or diffuse patterns in lymph nodes, that localize to the splenic white pulp and that produce interstitial, paratrabecular, and intertrabecular lymphoid aggregates in the bone marrow. Phenotypically, mantle cell lymphomas are B cell neoplasms that express pan B cell lineage antigens, CD5 and CD43, and that are negative for CD10 and CD23. On a genetic level, many cases of mantle cell lymphomas have the t(11;14)(q13;q32) that causes overexpression of cyclin-D1, a protein that can be demonstrated by immunohistochemistry in many examples of mantle cell lymphoma and that can be exploited diagnostically to distinguish mantle cell lymphomas from other low-grade B cell lymphoproliferative disorders. The differential diagnosis of mantle cell lymphoma includes small B cell lymphoma, lymphoplasmacytic lymphoma, nodal, extranodal, and splenic marginal zone lymphomas, and follicular small cleaved cell lymphoma. In most instances, these disorders can be separated from one another by morphology, distinctive immunophenotypic profiles, and genetic features.
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PMID:Mantle cell lymphoma. 1009 79

The human myeloid cell nuclear differentiation antigen (MNDA) is a nuclear antigen known to be expressed in mature myelomonocytic cell lines. An extensive immunocytochemical evaluation of fixed tissues confirmed MNDA expression in normal maturing granulocytes and monocytes and in acute nonlymphocytic leukemias and chronic myelogenous leukemia. MNDA was not detected in normal tissue histiocytes but was found in activated macrophages and foreign body giant cells associated with inflammation. Flow cytometric cell sorting of normal bone marrow established that MNDA is initially expressed in myeloid blast cells. Examination of lymphoid tissues showed a low level of expression in a population of normal mande B lymphocytes but not in germinal center cells or plasma cells. A subset of B cell neoplasms expressing MNDA included hairy cell leukemia, parafollicular (monocytoid) B cell lymphoma, mantle cell lymphoma, and small lymphocytic lymphoma. Cell sorting of normal bone marrow showed MNDA expression in CD20+/CD10-/CD5- B cells. MNDA was not detected in other normal bone marrow or all other nonhematopoietic cells. The hematopoietic cell-specific pattern of MNDA expression was elucidated through a comprehensive analysis of normal and neoplastic tissues, and the results provide further evidence of the coexpression of B- and myeloid cell markers in neoplastic B cells and identify a normal B cell population that might be related to the cell of origin of a subset of B cell neoplasms.
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PMID:Immunocytochemical analysis of MNDA in tissue sections and sorted normal bone marrow cells documents expression only in maturing normal and neoplastic myelomonocytic cells and a subset of normal and neoplastic B lymphocytes. 1049 38

We have analyzed the immunoglobulin heavy chain (VH) gene variable regions (CDR2 and FW3) of 101 Japanese cases with peripheral B cell neoplasms. When all except one case with a deletion were graphed by frequency of replacement mutation, the 100 cases could be separated into two groups: 24 cases with zero, one and two mutations (germline or low frequency of somatic mutation); and 76 cases with three or more mutations (medium to high frequency of somatic mutation). While most mantle cell lymphoma cases (11/13) showed germline or low frequency of somatic mutation, all cases of mucosa-associated lymphoid tissue (MALT) lymphoma (11/11), follicular lymphoma (three of three cases), plasma cell myeloma (seven of seven cases) and most cases of diffuse large B cell lymphoma (DLBCL; 42/47) belonged to the latter group. These 76 cases, therefore, may be considered to show somatic hypermutation. More than half of chronic lymphocytic leukemia/small lymphocytic lymphoma cases (CLL/SLL; eight of 13) showed a hypermutated VH gene and the ratio of replacement mutation: silent mutation in CDR2 of CLL/SLL was considerably higher compared with DLBCL and MALT lymphoma, showing somatic hypermutation. When comparing VH gene type of B cell-CLL (B-CLL) among our series and those in the literature, more cases of CD5+ B-CLL in the Western literature have the VH5 and VH6 family types, while more cases in Japan are reported to have VH4 family. The occurrence of VH families in B-CLL between Japanese and Western people seems to be comparable.
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PMID:Analysis of the immunoglobulin heavy chain gene variable region of 101 cases with peripheral B cell neoplasms and B cell chronic lymphocytic leukemia in the japanese population. 1050 19

Downregulation of apoptosis has been proposed as a mechanism of clonal expansion in low-grade B cell neoplasms. We have previously described an unusual case of CD5+ B cell lymphoma characterized by cycles of leukemic phase alternating with spontaneous remission. In the present study, we examined the involvement of apoptosis-related proteins in the progression of this cyclic lymphoma ex vivo. During the leukemic phases, the clonal cells were activated blasts expressing elevated levels of wild-type (wt) p53, Bcl-2, Bcl-x(L), and Bax, while Bak expression increased during the decline of lymphocytosis. Bax heterodimerized with Bcl-2 but not with Bcl-x(L). The anti-apoptotic Bcl-2/Bax heterodimers peaked during early leukemic phases and declined during regression. The elevation in Bcl-2, Bcl-x(L) and Bax expression during early leukemic phases seems to result from cell activation since a similar increase was induced by activating the remission phase leukemic cells in culture. The data suggest that wt p53, Bcl-x(L), and Bcl-2/Bax heterodimers support the accumulation of activated leukemic cells during the leukemic phases, while Bax and Bak may be involved in their decline during regression.
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PMID:Expression of wild-type p53 and Bcl-2 family genes oscillates with recurrent remission and relapse in an unusual case of low-grade lymphoma. 1101 90

In response to antigen stimulation, B cells undergo a germinal center(GC) reaction such as somatic hypermutations of the immunoglobulin variable region genes, which results in the production and selection of antigen-specific antibodies with increased affinity. Therefore, somatic hypermutations are considered to be a hallmark of GC B cells and their descendants. Pre-GC B cells(precursor B cells, immature B cells, naive B cells and CD5+ B cells) carry no somatic hypermutations, whereas GC B cells and post-GC B cells(memory B cells and plasma cells) express somatic hypermutations. This phenomenon is useful in identifying the cellular origin of various B-cell neoplasms. Precursor B-lymphoblastic leukemia/lymphoma, mantle cell lymphoma, and most B-CLL originate from pre-GC B cells, and follicular lymphoma, Burkitt's lymphoma, marginal zone B-cell lymphoma, diffuse large B-cell lymphoma and myeloma from GC B cells or post-GC B cells. Nodular lymphocyte-predominant Hodgkin's disease and most classical types of Hodgkin's disease are derived from GC B cells. Most human-B cell neoplasms including Hodgkin's disease are derived from GC B cells or their descendants. Molecular processes that modify the DNA of GC B cells, such as somatic hypermutation, class switching and receptor editing occur in the environment of the GCs, and increase the risk of malignant transformation.
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PMID:[Cellular origin of human B-cell neoplasms and Hodgkin's disease based on analysis of somatic hypermutations in the immunoglobulin variable region genes]. 1157 86

BACKGROUND: Modulation of the immune system by genetically modified lymphoma cell vaccines is of potential therapeutic value in the treatment of B cell lymphoma. However, the anti-tumor effect of any single immunogene transfer has so far been limited. Combination treatment of recombinant IL-2 and IL-12 has been reported to be synergistic for inducing anti-tumor responses in solid tumors but the potential of IL-2/IL-12 gene modified B cell lymphoma cells has not been explored yet. METHODS: Using three different human B cell lymphoma cell lines and primary samples from patients with B cell neoplasms, expression levels of the coxsackie B-adenovirus receptor (CAR) and alpha (v) integrins were analyzed by fluorescence-activated cell sorter (FACS). Adenoviral transduction efficiencies were determined by GFP expression analysis and IL-2 and IL-12 cytokine production was quantified by enzyme-linked immunosorbent (ELISA) assays. Proliferative activities of peripheral blood mononuclear cells (PBMC) stimulated with either cytokine derived from supernatants of transduced lymphoma cells were measured by cell proliferation (MTT) assays. An EuTDA cytotoxicity assay was used to compare cytotoxic activities of IL-2 and/or IL-12 stimulated PBMC against unmodified lymphoma cells. RESULTS: We found that B cell lymphoma cell lines could be transduced with much higher efficiency than primary tumor samples, which appeared to correlate with the expression of CAR. Adenoviral-expressed IL-2 and IL-12 similarly led to dose-dependent increases in proliferation rates of PBMC obtained from healthy donors. IL-2 and/or IL-12 transduced lymphoma cells were co-cultured with PBMC, which were assayed for their cytolytic activity against unmodified lymphoma cells. We found that IL-2 stimulated PBMC elicited a significant anti-tumor effect but not the combined effect of IL-2/IL-12 or IL-12 alone. CONCLUSION: This study demonstrates that the generation of recombinant adenovirus modified lymphoma cell vaccines based on lymphoma cell lines expressing IL-2 and IL-12 cytokine genes is technically feasible, induces increases in proliferation rates and cytotoxic activity of co-cultured PBMC, and warrants further development for the treatment of lymphoma patients in the future.
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PMID:Effects of recombinant adenovirus-mediated expression of IL-2 and IL-12 in human B lymphoma cells on co-cultured PBMC. 1548 77


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