Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In lymphoid follicles, CD4+ T lymphocytes provide contact-dependent stimuli to B cells that are critical for the generation of specific antibody responses in a process termed Th function. The CD4+ T cell-restricted surface activation protein, 5c8 Ag (T-BAM), has recently been shown to be a component of the contact-dependent helper signal to B cells. To further dissect this process, we utilized a Jurkat T cell lymphoma clone, termed D1.1, that constitutively expresses T-BAM and activates peripheral B cells to express surface CD23 in a contact-dependent mechanism that is inhibited by mAb anti-T-BAM (5c8). Similar to its effect on peripheral B cells, Jurkat D1.1 activates B cells from lymphoid organs, as well as a B cell lymphoma clone, RAMOS 266,4CN 3F10 (RAMOS 266), to up-regulate surface CD23. Interestingly, mAb to the B cell surface molecule, CD40 (mAb G28-5 and B-B20), inhibit D1.1 induced activation of RAMOS 266 and peripheral and lymphoid B cells. In contrast, mAb to CR2 or the adhesion molecules, LFA1, LFA3, or ICAM-1, have little effect. The inhibitory effect of anti-CD40 mAb on B cell activation induced by D1.1 is specific because anti-CD40 potentiates, rather than inhibits, the up-regulation of CD23 on B cells induced by rIL-4. Moreover, cross-linking CD40 molecules by anti-CD40 mAb bound to Fc gamma RII+ (CD32) L cells induces B cell CD23 expression. In vivo, T-BAM-expressing cells are CD4+ T cells that are restricted to lymphoid organs and are localized in the mantle and centrocytic zones of lymphoid follicles and the spleen periarteriolar lymphoid sheath in association with CD40+ B cells. Taken together, these data demonstrate that T-BAM on T cells and CD40 on B cells are involved in contact-dependent T-B help interactions that occur in lymphoid follicles.
 ...
PMID:Molecular interactions mediating T-B lymphocyte collaboration in human lymphoid follicles. Roles of T cell-B-cell-activating molecule (5c8 antigen) and CD40 in contact-dependent help. 128 Nov 89

Human Immunodeficiency Virus type 1 (HIV-1) infects CD4+ T lymphocytes and various other cell types, including B cells. Since HIV-1 seropositive individuals have high numbers of B cells carrying Epstein-Barr Virus (EBV), and are at high risk for development of EBV-associated lymphoproliferative diseases, we studied the mode of HIV-1 infection in four EBV-positive lymphoblastoid B-cell lines (LCLs) as well as some molecular and biological features of the B cells infected by both viruses. We found that LCL cells were successfully infected in vitro by HIV-1, despite the lack of CD4 antigen expression on the cell membrane. LCL cells displayed a persistent, productive, and non-cytopathic infection. Moreover, HIV-1 infection induced reactivation of EBV latent genomes in one cell line. Following HIV-1 infection, LCL cells showed a decrease in B-cell activation markers CD23 and CD39, and an increase in CD10 immature B-cell antigen. Not all cells in each LCL expressed HIV-1 antigens, but all CD10+ cells also co-expressed the HIV-1 envelope protein gp 120. Furthermore, HIV-1 infected LCL cells grew as disperse suspensions, and formed more agar colonies than control, non-HIV-1-infected LCLs. These findings raise the possibility that HIV-1 might play a role in EBV reactivation, and in B-cell lymphoma pathogenesis in AIDS patients.
 ...
PMID:Morphological and phenotypical changes in EBV positive lymphoblastoid cells infected by HIV-1. 131 75

Using a large range of monoclonal antibodies to specific cluster differentiation antigens the phenotypes of a series of high-grade non-Hodgkin's lymphomas of B- and T-cell type were investigated. Cell ploidy and proliferative fraction were assessed by fluorescent staining of DNA and flow cytometry and data on the incidence of complete clinical remission were obtained. With the exception of some lymphoblastic lymphomas, high-grade B-cell lymphomas normally expressed the pan B-cell antigens CD19 and CD22 but only immunoblastic lymphomas consistently expressed the pan B marker CD20. Variable, generally weak expression of CD21 was observed whilst CD23 expression was most prevalent in rapidly proliferative cases and in Burkitt's and centroblastic lymphomas. A rapidly proliferative, multilobated B-cell lymphoma displayed phenotypic properties intermediate between centroblastic and immunoblastic lymphomas. The T-cell lymphomas generally showed low proliferative activity and expression of CD4 prevailed over CD8. Most cases also showed CD2 and CD5 positivity with some also showing CD3 and CD7 expression. Patients with rapidly proliferative diploid or DNA aneuploid tumours obtained complete remission more readily than patients with lowly proliferative diploid tumours. An excess of early deaths occurred among T-cell cases.
 ...
PMID:Ploidy, proliferative activity, cluster differentiation antigen expression and clinical remission in high-grade non-Hodgkin's lymphoma. 350 51

We describe a patient with stage IV non-Hodgkin's lymphoma (NHL) and a t(11;18)(q21;q21) translocation. He presented with a gastric small B-cell lymphocytic lymphoma, expressing IgAL immunoglobulins without expression of CD10, CD5, and CD23 antigens. The lymphoma was the final development of a 6-year history of a monoclonal IgAL increase complicated by severe renal failure due to membranoproliferative glomerulonephritis. The clinical, histological, immunologic, and cytogenetic features of this patient are very similar to those observed in the five other patients with t(11;18) reported to date. This translocation therefore seems to delineate a new subtype of diffuse small B-cell lymphoma with involvement of mucosal sites. Involvement of the BCL2 oncogene on 18q21 could not be detected using molecular techniques with 5' as well as 3' BCL2 probes, indicating that other, so far unknown, genes relevant to lymphoid differentiation could be located in 18q21 and 11q21.
 ...
PMID:t(11;18)(q21;q21) may delineate a spectrum of diffuse small B-cell lymphoma with extranodal involvement. 768 56

Striking antigenic changes were elicited by interleukin 4 (IL-4) in the Farage human B-cell lymphoma line. After 2 days of incubation with IL-4 the expression of CD23, CD54 (ICAM-1), CD58 (LFA-3) was increased while the levels of CD21, CD22, CD38 were diminished. Prolonged incubation of Farage cells with IL-4 for 6-8 days led to increased expression of CD11a (LFA-1) CD39, CD40, and to disappearance of CD21 and CD38. The modulation of antigenic properties of Farage cells was associated with enhancement of their homotypic adhesiveness and the formation of giant clumps of cells. The recovery of Farage cells which had been exposed to IL-4 for six days was not complete and eleven days after withdrawal of the cytokine, these cells still displayed a lower level of CD21 and of CD38 than control cells. Cycling and non-cycling cells did not appear to differ in their antigenic properties, indicating that modification of the antigenic profile did not result from cell selection or cell arrest. These results showed that the pleiotropic effect of IL-4 on various cell surface structures on malignant human B cells proceeds at different rates suggesting that distinct metabolic pathways may regulate their expression.
 ...
PMID:Kinetics of the pleiotropic effect of interleukin 4 on the surface properties of human B-lymphoma cells. 786 83

Mediastinal large B cell lymphomas are uncommon neoplasms that are thought to originate from thymic B cells. An unusual feature of these neoplasms is that they often lack surface immunoglobulin (Ig), a molecule ubiquitously expressed by most mature B cells. In the present study we have analyzed 12 cases of mediastinal large B cell lymphoma for the expression of the mb-1/CD79a polypeptide. This is a component, together with B29/CD79b, of a heterodimer that is associated with surface Ig on normal B cells. Our aim was to see whether loss of Ig in this type of lymphoma is associated with loss of the accompanying CD79a molecule. We have also evaluated 128 B cell lymphomas of other categories to see whether any of them show discordance between mb-1 and Ig expression and analyzed 30 T cell lymphomas as Ig-negative controls. We found that 5 of the 7 mediastinal large B cell lymphomas with interpretable staining results for both mb-1 and Ig, lack Ig but expressed CD79a (mb-1). This phenotype was very rare in other categories of B cell lymphoma, being found among 110 cases in only 5 cases that were all follicular lymphoma. The remaining 105 B cell lymphomas displayed mb-1+/Ig+ phenotype. All 30 T cell lymphomas were mb-1 negative. We conclude that discordant mb-1/Ig expression occurs commonly in mediastinal large B cell lymphomas. In addition, the finding that 11 of 12 of these neoplasms express a phenotype (CD10-, CD19+, CD20+, CD21-, CD22+, CD23-/+) that is very similar to that described for thymic medullary B cells reinforces the idea that most mediastinal large B cell lymphomas are of thymic B cell origin. The correlation between mb-1 and Ig staining patterns in B cell lymphomas of other categories reveals that in the majority (90%), expression of the antigen receptor complex parallels that of mature B cells. These data therefore confirm that the expression of the mb-1 protein provides independent strong evidence for the B lineage of lymphomas and may be used for their routine phenotypic characterization.
 ...
PMID:Discordant expression of immunoglobulin and its associated molecule mb-1/CD79a is frequently found in mediastinal large B cell lymphomas. 788 54

The low affinity receptor for IgE (Fc epsilon RII or CD23), expressed primarily on mouse B cells, is known to be upregulated by interleukin-4 (IL-4) at both the mRNA and protein levels. Fc epsilon RII expression is superinduced when the IL-4 is combined with cell activation. In order to explore the molecular regulation of Fc epsilon RII expression, mouse B cell lines were screened to develop a cell line model. The B cell lymphoma A20.1, was found to behave in a manner similar to mouse B cells in that Fc epsilon RII levels are very low on cells cultured in media alone (< 10(3)/cell), increased by culture in the presence of IL-4, and superinduced by LPS and IL-4 (> 10(5)/cell). The steady state mRNA levels for Fc epsilon RII corresponded to the level of cell surface expression. Transcription assays indicated that the Fc epsilon RII level increases could be explained entirely by increased transcription rates. The A20.1 cell line was subsequently used to analyse the Fc epsilon RII promoter. Nested deletion analysis of the 1.3 kB 5' of the mouse Fc epsilon RII transcription start site, using CAT reporter plasmids transfected into A20.1 cells, identified major elements activating the Fc epsilon RII promoter within 250 bp of the transcription start site. Constructs containing greater than 250 bp of 5' sequence showed significantly reduced CAT activity suggesting negative regulatory regions. Coincident with the restricted tissue expression of murine Fc epsilon RII, the promoter was B cell specific in that little CAT expression was seen in fibroblast, mast cells or T cell lines. Expression was seen, however, in both mouse and human B cell lines. Finally, the promoter was analysed for response to IL-4. Stimulation with IL-4 plus LPS resulted in only a modest increase in CAT activity (approximately 2-fold), in contrast to transcription assays, where increases approximated that seen at the cell surface. Thus, the IL-4 response must also require sequences distal to the regions examined.
 ...
PMID:Molecular mechanisms of murine Fc epsilon RII/CD23 regulation. 793 5

The authors studied 56 cases of diffuse low-grade B-cell lymphoma using frozen tissue sections and a large panel of monoclonal antibodies that distinguish subsets of normal B cells. They compared the immunophenotypes with the histologic subtypes defined by the Rappaport classification, Working Formulation, and Kiel classification to correlate antigen expression with the morphologic subtypes defined in these classification schemes and to define the contribution of immunophenotype to clinically relevant subclassification. All categories in all classifications showed some heterogeneity of antigen expression; however, antigen expression correlated better with four major subgroups defined by the Kiel classification: (1) CD5+ CD10- CD23+ CD43+: chronic lymphocytic leukemia (CLL); (2) CD5+ CD10-/+CD23- CD43+: centrocytic (mantle cell) lymphoma; (3) CD5- CD10+/- CD23-/+ CD43-: centroblastic/centrocytic (CB/CC) lymphoma; and (4) CD5- CD10- CD23-/+CD43-/+: immunocytoma, mucosa-associated lymphoid tissue (MALT)-type, and monocytoid B-cell lymphoma. These subgroups had distinctive clinical features. Patients with centrocytic lymphoma were predominantly male (5.5:1) and had a significantly worse probability of survival than those with either CLL or MALT-type lymphoma (P = 0.001). The group with CB/CC lymphoma had an equal male-female ratio and an intermediate prognosis. Most patients with MALT-type and nodal monocytoid B-cell lymphomas were female (2:1); the disease-free survival for patients with extranodal MALT-type lymphoma was significantly better than that for all patients with other lymphoma subtypes except CB/CC (P < 0.01). The group with non-MALT immunocytoma had a slight male predominance, a high frequency of monoclonal gammopathy, and an intermediate prognosis. In differential diagnosis, CD23 was useful in distinguishing B-cell CLL from centrocytic lymphoma (P < 0.0001); CD5 (P < 0.0001), CD6 (P < 0.005), and CD43 (P < 0.0001) distinguish centrocytic lymphoma from CB/CC lymphoma; and CD10 (P < 0.005), CD43 (P = 0.06), Leu-8 (P = 0.08), and Ig heavy chain (P = 0.01) may help distinguish CB/CC lymphoma from immunocytoma, monocytoid B-cell lymphoma, and MALT-type lymphoma. Differences in antigen expression and clinical features among these Kiel classification subgroups suggest that they represent distinct biologic entities. The Working Formulation categories do not delineate these diseases clearly.
 ...
PMID:Diffuse low-grade B-cell lymphomas. Four clinically distinct subtypes defined by a combination of morphologic and immunophenotypic features. 821 30

Plasma levels of the soluble fragments of Fc epsilon RII/CD23 (sCD23/IgE-binding factor) were measured to assess the level of activation of B lymphocytes associated with Epstein-Barr virus infection in 28 patients who received living-related liver transplantation and were treated with FK506 and steroids. In 6 patients with symptoms of EBV infection (EBV-related disorders), the plasma concentration of sCD23 increased to more than 9.8 ng/ml at the onset of symptoms. In a patient with B cell lymphoma, the plasma levels of sCD23 increased significantly when peripheral lymphadenopathy was noticed, and remained more than 10 ng/ml during the terminal period. In 4 of 6 patients, the increase of plasma levels of sCD23 preceded the increase of anti-EBV capsid antigen IgM. In the other 2 of 6 patients, there was no significant increase of the antibody, despite the integration of EBV DNA in the mononuclear cells in their ascites. The plasma levels of sCD23 of the patients without symptoms of EBV infection did not exceed 7.5 ng/ml. In contrast, the proportion of CD20+/CD23+ B lymphocytes in peripheral blood mononuclear cells was not significantly different in the patients with EBV-related disorders and those with latent asymptomatic EBV infection. Therefore, the plasma level of sCD23 is a sensitive and useful marker of EBV-related polyclonal and/or monoclonal B cell proliferation in transplanted patients with immunosuppression.
 ...
PMID:Soluble CD23 as a sensitive marker for Epstein-Barr virus-related disorders after liver transplantation. 824 9

Clinical, histologic, cytogenetic, and molecular genetic data of 31 patients with extranodal, nodal, and splenic marginal zone B-cell lymphoma (MZBCL) are presented. Despite these variable clinical manifestations, a similar spectrum of morphologic features as well as distinctive immunophenotypic findings were noted. In all cases, a monotypic B-cell proliferation consistently negative for CD5, CD10, and CD23 was found expanding the marginal zone of the B follicle with and without colonization of the follicle centers. Clonal chromosomal abnormalities were detected in 23 of the 31 patients. Recurrent aberrations included whole or partial trisomy 3 (18 cases), trisomy 18 (9 cases), and structural rearrangements of chromosome 1 with breakpoints in 1q21 (9 cases) or 1p34 (6 cases), all of which were seen in extranodal, nodal, as well as splenic MZBCL. Abnormalities of the additional chromosome 3, such as +del(3)(p13),+i(3)(q10), or structural changes involving the distal part of the long arm, were evident in 9 of the 18 cases. All recurrent abnormalities were found in MZBCL more frequently than in other histologic entities of B-cell non-Hodgkin's lymphoma (B-NHL). None of the known lymphoma-associated chromosomal changes or rearrangements of the BCL1, BCL2, BCL3, BCL6, and CMYC genes were detected. We conclude that MZBCL represent a distinct entity of B-NHL with characteristic morphologic and immunophenotypic features and particular chromosomal abnormalities, and that a close histogenetic relationship between extranodal, nodal, and splenic MZBCL is likely, although the clinical presentation may vary.
 ...
PMID:Marginal zone B-cell lymphomas of different sites share similar cytogenetic and morphologic features. 869 24


1 2 3 4 5 6 7 8 9 10 Next >>