Search results for " B-Cell"
showing 10 items of 207 documents
Double Negative (CD19+IgG+IgD-CD27-) B Lymphocytes: A New Insight from Telomerase in Healthy Elderly, in Centenarian Offspring, and in Alzheimer’s Di…
2014
Background: We have previously reported the increase of IgD-CD27- (Double Negative, DN) B cell population in the aged. These memory B cells have short telomeres and poor abilities to proliferate in vitro. Here, we investigated whether the low ability of DN B cells to proliferate depends on the expression levels of the CD307d and CD22 inhibitory receptors or whether DN B cells can proliferate and reactivate telomerase by the engagement of both innate and adaptive immune receptors. Methods: Phenotypic analyses were made by using flow cytometry. Quantitative analysis of telomerase activity was made by using a TRAP and a photometric enzyme immunoassay in young, healthy elderly, centenarian offs…
Overexpression of Bcl-3 inhibits the development of marginal zone B cells.
2013
The transcription factor Bcl-3 functions as a proto-oncogene via regulation of cell proliferation and apoptosis. Bcl-3 is an atypical member of the IκB family and plays a central role in the immune response through interactions with the NF-κB subunits p50 and p52. To investigate the impact of Bcl-3 on B-cell maturation and regulation, we generated mice that overexpress Bcl-3 specifically in B cells. Interestingly, these mice lack marginal zone B cells and exhibit a significant reduction in the number of B-1 B cells. Further, B cells from these mice are impaired in their proliferative capacity. Our data demonstrate that the overexpression of the transcription factor Bcl-3 inhibits germinal c…
Cytokines in the pathophysiology and treatment of chronic B-cell malignancies
1995
Chronic B-cell malignancies are characterized by accumulation of transformed B cells of low proliferative index in lymphatic and extralymphatic tissues. Cytokines do not appear to play a role in the primary step of transformation. However, proliferation as well as inhibition of apoptosis of malignant B cells can readily be explained by cytokine effects. Clinical trials of interferons (IFN) and interleukin-2 alone or in combination have been performed in patients with hairy cell leukemia (HCL), CLL, and low- and intermediate-grade non-Hodgkin's lymphoma. While IFN alpha became standard therapy of HCL, responses in other entities were variable, ranging from 0 to 70% in selected populations. C…
Efficacy of bendamustine and rituximab in splenic marginal zone lymphoma: results from the phase II BRISMA/IELSG36 study.
2018
Splenectomy in addition to immunotherapy with rituximab can provide quick and sometimes durable disease control in patients with splenic marginal zone lymphoma (SMZL). However, systemic chemotherapy is ultimately required in many cases. The BRISMA (Bendamustine-rituximab as first-line treatment of splenic marginal zone lymphoma)/IELSG (International Extranodal Lymphoma Study Group)36 trial is an open-label, single arm phase II study designed by the IELSG in cooperation with the Fondazione Italiana Linfomi and the lymphoma Study Association according to Simon's two-stage method. The primary endpoint was complete response rate. Fifty-six patients with SMZL diagnosis confirmed on central revis…
ABCL-346: Overall Survival with Tafasitamab + Lenalidomide (LEN) vs Routinely Administered Therapies for ASCT-Ineligible Relapsed or Refractory (R/R)…
2021
Context Tafasitamab+LEN, a chemotherapy-free, novel treatment for R/R DLBCL, demonstrated efficacy in ASCT-ineligible patients in the single-arm Phase II L-MIND study (NCT02399085). Objective To compare outcomes in patients treated with tafasitamab+LEN in the L-MIND study with matched patient populations treated with commonly administered NCCN-/ESMO-recommended therapies for non-transplant-eligible patients with R/R DLBCL in routine clinical practice. Design RE-MIND2 (NCT04150328) is an observational, retrospective cohort study. The L-MIND tafasitamab+LEN cohort was matched with RE-MIND2 patients using estimated propensity score-based 1:1 nearest neighbor matching balanced for nine patient …
Splenic marginal zone lymphoma.
2002
Splenic marginal zone lymphoma (SMZL) is a specific low-grade small B-cell lymphoma that is incorporated in the World Health Organization classification. Characteristic features are splenomegaly, moderate lymphocytosis with villous morphology, intrasinusoidal pattern of involvement of various organs, especially bone marrow, and relative indolent course. Tumor progression with increase of blastic forms and aggressive behavior are observed in a minority of patients. Molecular and cytogenetic studies have shown heterogeneous results probably because of the lack of standardized diagnostic criteria. To date, no definitive therapy has been established. Therapeutic options include treatment absten…
Successful Treatment of Catastrophic Antiphospholipid Antibody Syndrome (CAPS) Associated With Splenic Marginal-zone Lymphoma With Low-molecular Weig…
2008
ABSTRACT Case report A 69-year-old woman with splenic marginal-zone lymphoma was admitted with progressive abdominal pain and splenomegaly as the suspected cause of pain. Rituximab treatment (375 mg/m 2 ) had been initiated on the day of admission. Abdominal computerized tomography revealed splenic infarction. Laboratory tests showed elevation of liver enzymes and creatinine, low platelet count, prolonged partial thromboplastin time, and lupus anticoagulant positivity. The diagnosis of catastrophic antiphospholipid antibody syndrome was made. Weight-adjusted low-molecular weight heparin therapy was initiated. Freedom from symptoms and normalization of liver enzymes and creatinine occurred w…
Homozygous deletions localize novel tumor suppressor genes in B-cell lymphomas
2007
AbstractIntegrative genomic and gene-expression analyses have identified amplified oncogenes in B-cell non-Hodgkin lymphoma (B-NHL), but the capability of such technologies to localize tumor suppressor genes within homozygous deletions remains unexplored. Array-based comparative genomic hybridization (CGH) and gene-expression microarray analysis of 48 cell lines derived from patients with different B-NHLs delineated 20 homozygous deletions at 7 chromosome areas, all of which contained tumor suppressor gene targets. Further investigation revealed that only a fraction of primary biopsies presented inactivation of these genes by point mutation or intragenic deletion, but instead some of them w…
The down-regulation of miR-125b in chronic lymphocytic leukemias leads to metabolic adaptation of cells to a transformed state
2012
AbstractMiR-125b-1 maps at 11q24, a chromosomal region close to the epicenter of 11q23 deletions in chronic lymphocytic leukemias (CLLs). Our results establish that both aggressive and indolent CLL patients show reduced expression of miR-125b. Overexpression of miR-125b in CLL-derived cell lines resulted in the repression of many transcripts encoding enzymes implicated in cell metabolism. Metabolomics analyses showed that miR-125b overexpression modulated glucose, glutathione, lipid, and glycerolipid metabolism. Changes on the same metabolic pathways also were observed in CLLs. We furthermore analyzed the expression of some of miR-125b–target transcripts that are potentially involved in the…
Direct Cellular Interaction with Activated CD4+T Cells Overcomes Hyporesponsiveness of B-Cell Chronic Lymphocytic Leukemiain Vitro
1998
The proliferative response of clonal B cells from patients with chronic lymphocytic leukemia (B-CLL) is drastically reduced compared to normal B lymphocytes stimulated via the B cell antigen receptor complex or by CD40 ligation. In the present study we demonstrate that hyporesponsiveness of CLL-B cells can be overcome by stimulatory pathways mediated by activated CD4(+) T cells. In contrast to CD40 ligation, costimulation with activated T cells promotes a proliferative response in CLL-B cells identical to that in normal B cells. Furthermore, coculture with activated T cells improved survival of CLL-B cells in vitro. Differentiation of CLL-B cells into IgM producing cells was promoted, as we…