Search results for "B-Cell"

A practical algorithmic approach to mature aggressive B cell lymphoma diagnosis in the double/triple hit era. Selecting cases, matching clinical bene…

2019

An accurate diagnosis of clinically distinct subgroups of aggressive mature B cell lymphomas is crucial for the choice of proper treatment. Presently, precise recognition of these disorders relies on the combination of morphological, immunophenotypical, and cytogenetic/molecular features. The diagnostic workup in such situations implies the application of costly and time-consuming analyses, which are not always required, since an intensified treatment option is reasonably reserved to fit patients. The Italian Group of Haematopathology proposes herein a practical algorithm for the diagnosis of aggressive mature B cell lymphomas based on a stepwise approach, aimed to select cases deserving mo…

The B-cell receptor in control of tumor B-cell fitness: Biology and clinical relevance

2019

Surface expression of a functional B cell antigen receptor (BCR) is essential for the survival and proliferation of mature B cells. Most types of B-cell lymphoproliferative disorders retain surface BCR expression, including B-cell non-Hodgkin lymphomas (B-NHL) and chronic lymphocytic leukemia (CLL). Targeting BCR effectors in B-NHL cell lines in vitro has indicated that this signaling axis is crucial for malignant B cell growth. This has led to the development of inhibitors of BCR signaling, which are currently used for the treatment of CLL and several B-NHL subtypes. Recent studies based on conditional BCR inactivation in a MYC-driven mouse B-cell lymphoma model have revisited the role of …

Early diagnosis of intravascular large B-cell lymphoma.

2016

Early ROS-mediated DNA damage and oxidative stress biomarkers in Monoclonal B Lymphocytosis

2012

Monoclonal B Lymphocytosis (MBL) is defined as asymptomatic monoclonal B-cell expansion characterised by a CLL-phenotype, but with less than 5 x 10(9)/I circulating cells. Reactive oxygen species (ROS)-mediated cell damage plays a critical role in the initiation of carcinogenesis as well as in malignant transformation. The goal of this study was to perform an analysis of the oxidative stress statuses of patients affected by MBL and chronic lymphocytic leukaemia (CLL). We examined peripheral blood and urine specimens from 29 patients with MBL, 55 with CLL and 31 healthy subjects. There was a significant increase in the occurrence of the mutagenic base 8-oxo-2'-deoxiguanosine (8-oxo-dG) in th…

CD73-generated extracellular adenosine in chronic lymphocytic leukemia creates local conditions counteracting drug-induced cell death

2011

Abstract Extracellular adenosine (ADO), generated from ATP or ADP through the concerted action of the ectoenzymes CD39 and CD73, elicits autocrine and paracrine effects mediated by type 1 purinergic receptors. We have tested whether the expression of CD39 and CD73 by chronic lymphocytic leukemia (CLL) cells activates an adenosinergic axis affecting growth and survival. By immunohistochemistry, CD39 is widely expressed in CLL lymph nodes, whereas CD73 is restricted to proliferation centers. CD73 expression is highest on Ki-67+ CLL cells, adjacent to T lymphocytes, and is further localized to perivascular areas. CD39+/CD73+ CLL cells generate ADO from ADP in a time- and concentration-dependen…

Lymphoma cell apoptosis in the liver induced by distant murine cytomegalovirus infection.

2006

ABSTRACTCytomegalovirus (CMV) poses a threat to the therapy of hematopoietic malignancies by hematopoietic stem cell transplantation, but efficient reconstitution of antiviral immunity prevents CMV organ disease. Tumor relapse originating from a minimal residual leukemia poses another threat. Although a combination of risk factors was supposed to enhance the incidence and severity of transplantation-associated disease, a murine model of a liver-adapted B-cell lymphoma has previously shown a survival benefit and tumor growth inhibition by nonlethal subcutaneous infection with murine CMV. Here we have investigated the underlying antitumoral mechanism. Virus replication proved to be required, …

Bendamustine with or without rituximab in the treatment of relapsed chronic lymphocytic leukaemia: an Italian retrospective study.

2011

To retrospectively assess the efficacy of bendamustine alone and with rituximab (R-B), 109 patients with relapsed chronic lymphocytic leukaemia (CLL) were enrolled in 24 Italian centres. The median age was 66 years (range 39-85). Forty-three percent of patients had relapsed and 57% were resistant (median previous therapies = 3; range 1-8). Twenty-two patients received bendamustine alone and 87 patients received R-B (median B dosage: 100 mg/m(2) per day, range 90-130 mg/m(2) per day). The overall response rate was 69·6% (complete response 28·6%; partial response 41%), and was significantly higher in patients treated with R-B (P = 0·014) and in those responsive to the previous treatment (P=0·…

Trafficking phenotype and production of granzyme B by double negative B cells (IgG(+)IgD(-)CD27(-)) in the elderly.

2013

The impairment of humoral immune response in elderly humans has been extensively demonstrated. We have reported the increase of memory B cells (IgG(+)IgD(-)CD27(-), double negative, DN) population in the elderly, in which there is also a typical inflammatory micro-environment. In order to evaluate whether this pro-inflammatory status could influence the trafficking phenotype of naïve/memory B cells, we have assessed the expression of CCR7, CCR6, CXCR3, CXCR4, CXCR5 and CD62L on naïve/memory B cell subpopulations in young and elderly subjects. Moreover, the combination of pro-inflammatory interleukin-21 (IL-21) and B cell receptor (BCR) stimulation enables B cells to produce and secrete gran…

Lysis of human pancreatic adenocarcinoma cells by autologous HLA-class I-restricted cytolytic T-lymphocyte (CTL) clones.

1993

From the primary site of a pancreatic adenocarcinoma (patient BE) a permanent cell line (MZ-PC-2) was established in tissue culture. In the course of mixed lymphocyte-tumor-cell cultures (MLTC) with autologous blood-derived lymphocytes, we isolated CTL clones that lysed autologous tumor cells but not autologous EBV-transformed B cells (EBV-B) and not K562. Pre-treatment of MZ-PC-2 cells with IFN-gamma was required to obtain significant lysis in 4-hr cytotoxicity assays. IFN-gamma was superior to IFN-alpha in that respect. Among MLTC responder lymphocytes, tumor-reactive CTL proliferated more strongly in response to MZ-PC-2 cells treated with IFN-gamma than to untreated tumor cells. Three CT…

Lysis of human melanoma cells by autologous cytolytic T cell clones. Identification of human histocompatibility leukocyte antigen A2 as a restriction…

1989

From the peripheral blood of the melanoma patient (AV), we derived cytolytic T lymphocyte (CTL) clones that lysed the autologous tumor line SK-MEL-29, but not autologous EBV-B cells, K562, and other tumor targets. By immunoselection experiments it was shown that the CTL clones recognized at least three different antigens on the autologous tumor cells. We demonstrate here that these melanoma antigens are presented to the CTL in association with HLA-A2. First, HLA-A2-reactive pregnancy sera as well as an mAb against HLA-A2 inhibited the CTL lysis. Second, immunoselected melanoma subclones that were resistant to lysis by CTL clones against the three antigens described were found to lack expres…