Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q06643 (non-Hodgkin's lymphoma)
 11,307 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CD40 plays an important role in T cell mediated B cell proliferation and isotype switching. The cytokines tumor necrosis factor (TNF)-alpha and lymphotoxin (LT)-alpha are expressed by B cells, and are known to play a role in B cell activation. We have studied TNF-alpha and LT-alpha expression in human tonsillar B cells following stimulation with anti-CD40 mAb. Anti-CD40 induced weak TNF-alpha mRNA expression but strong LT-alpha mRNA expression and had little effect on the constitutive expression of LT-beta mRNA in B cells. Induction of TNF-alpha mRNA was inhibited by actinomycin D suggesting that CD40 ligation results in transcriptional activation of the TNF-alpha and LT-alpha genes. Anti-CD40 caused minimal increase in the expression of TNF-alpha on the B cell membrane and no detectable secretion of TNF-alpha. Anti-CD40 as well as soluble CD40 ligand caused sustained induction of LT-alpha on the membrane of the B cells lasting up to 120 h but induced no detectable secretion of LT-alpha. IL-4, a cytokine known to synergize with anti-CD40 in inducing B cell proliferation and isotype switching, augmented the induction of LT-alpha mRNA and of mLT-alpha expression by anti-CD40. These results indicate that CD40 ligation vigorously induces expression of membrane LT-alpha in B cells and that membrane LT-alpha may play a role in CD40 mediated B cell activation.
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PMID:CD40 ligation induces lymphotoxin alpha gene expression in human B cells. 753 97

Peripheral blood lymphocytes of a patient with follicular B-cell non-Hodgkin's lymphoma (B-NHL) were immortalized in vitro by Epstein-Barr virus (EBV). Eight cell lines were obtained (termed BNS1, BNS2-1 through BNS2-7), which showed a pattern of idiotypic (id) Ig surface expression and Ig JH and kappa gene rearrangement, identical to that of the parent cells (termed NS), confirming their neoplastic origin. Induction of allogeneic T-cell proliferation by NS cells was mediated by HLA-DR, leukocyte function-associated antigen-1 (LFA-1), LFA-3, B7-1/CD80, and CTLA4 and resulted in the upregulation (LFA-3, intercellular adhesion molecule-1 [ICAM-1], CD40) and induction (B7-1/CD80, B7-2/CD86, L16/activated LFA-1) of accessory molecules on NS cells. In turn, responder T lymphocytes were induced to express B7-1/CD80, B7-2/CD86, CD40 ligand (CD40L), ICAM-1, L16/activated LFA-1, and HLA-DR, reflecting bidirectional signaling between T lymphocytes and B-NHL cells. Preactivation of NS cells by EBV transformation or CD40 engagement resulted in enhanced expression of accessory molecules and abolished the requirement for accessory cells during allostimulation. These resting and activated clonal B cells will be useful in further dissecting the requirements for B-NHL costimulation.
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PMID:Functional expression of adhesion receptors and costimulatory molecules by fresh and immortalized B-cell non-Hodgkin's lymphoma cells. 774 41

Translocations involving the BCL-6 gene are common in the diffuse large cell subtype of non-Hodgkin's lymphoma. Invariably, the BCL-6 coding region is intact, but its 5' untranslated region is replaced with sequences from the translocation partner. The present study shows that BCL-6 expression is regulated in lymphocytes during mitogenic stimulation. Resting B and T lymphocytes contain high levels of BCL-6 mRNA. Stimulation of mouse B cells with anti-IgM or IgD antibodies, bacterial lipopolysaccharide, phorbol 12-myristate 13-acetate plus ionomycin, or CD40 ligand led to a five-fold to 35-fold decrease in BCL-6 mRNA levels. Similar downregulation of BCL-6 mRNA was seen in human B cells stimulated with Staphylococcus aureus plus interleukin-2 or anti-IgM antibodies and in human T lymphocytes stimulated with phytohemagglutinin. BCL-6 mRNA levels began to decrease 8 to 16 hours after stimulation, before cells entered S phase. Although polyclonal activation of B cells in vitro invariably decreased BCL-6 MRNA expression, activated B cells from human germinal centers expressed BCL-6 mRNA at levels comparable to the levels in resting B cells. Despite these similar mRNA levels, BCL-6 protein expression was threefold to 34-fold higher in germinal center B cells than in resting B cells, suggesting that BCL-6 protein levels are controlled by translational or posttranslational mechanisms. These observations suggest that the germinal center reaction provides unique activation signals to B cells that allow for continued, high-level BCL-6 expression.
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PMID:BCL-6 expression during B-cell activation. 865 41

An increasing amount of literature has been published concerning the interaction of the CD40 antigen and its ligand with regard to normal B cell ontogeny. In this review, an overview of the CD40 antigen and the CD40 ligand is given, focussing on their possible role in B cell malignancies. Data on the expression of the CD40 antigen on various B cell malignancies (acute and chronic leukemias, non-Hodgkin's lymphoma and multiple myeloma) are presented. The recently developed novel culture "CD40 system" is described. This system is a powerful tool used to culture normal B cells, but also most malignant B cells. We demonstrate in addition a more prominent role of the human Fc receptor presenting murine fibroblasts in the "CD40 system", especially in relation to cultured plasma cells. Finally, some important applications of the "CD40 system" are also summarized.
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PMID:The role of the CD40 antigen on malignant B cells. 881 71

The in vivo production of interleukin (IL)-10, IL-6, IL-2, and tumor necrosis factor (TNF)-alpha in tumor samples was investigated by immunohistochemistry in 54 non-Hodgkin's lymphomas (NHLs). Respectively, 55, 89, 23, and 29% of tumor samples were found positive for IL-10, IL-6, IL-2, and TNF-alpha expression by immunohistochemistry. Using reverse transcription-PCR, the mRNA of IL-10 and IL-6 were detectable in all samples tested and in 90 and 34% of the samples for TNF-alpha and IL-2, respectively. In 13 patients, fresh tumor tissue was available for B NHL cell purification with Dynabeads. IL-10, IL-6, IL-2, and TNF-alpha were detectable in the supernatant of 38, 100, 0, and 23% of purified tumor cell preparations (PTCPs), respectively. All patients with detectable IL-10 in culture had increased serum IL-10. IL-6 production by tumor cells and serum IL-6 levels were also found to be highly correlated (P < 0.0001). This suggests that tumor cells are a major source of serum IL-1O and IL-6 in these patients. Exogenous IL-10, IL-6, IL-2, and TNF-alpha significantly enhanced the [3H]thymidine uptake in 13 of 13 (100%), 5 of 13 (38%), 9 of 13 (69%), and 2 of 10 (20%) PTCPs costimulated with anti-CD40, respectively. IL-2, IL-6, and TNF-alpha synergized with IL-10 in 54, 23, and 30% of PTCPs. The combination of IL-10, IL-2, and IL-6 induced the maximal level of proliferation in 12 (92%) of 13 PTCPs. CD40 ligand mRNA expression was also detectable in vivo using reverse transcription-PCR in 28 of the 29 (97%) tumor samples tested, including 11 of those tested for [3H]thymidine incorporation. These results show that IL-1O, IL-6, IL-2, and TNF-alpha are produced in NHL tumors and may cooperate in vivo to increase NHL cell proliferation.
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PMID:Interleukin (IL)-10 and IL-6 are produced in vivo by non-Hodgkin's lymphoma cells and act as cooperative growth factors. 896 7

The in vitro analysis of growth regulation in low-grade B non-Hodgkin's lymphoma (B-NHL) is hampered by the rapid apoptotic death of the malignant B cells ex vivo. A complex culture system, using murine CDw32 transfected fibroblasts (LTK-cells), IL-4 and anti-CD40 mAb, has been established for the propagation of normal mature B cells in vitro. We investigated the influence of the different components of this coculture system on cell survival and apoptosis of B-NHL cells. Nine samples from patients with follicular lymphoma and from eight patients with immunocytoma were analyzed. No cell proliferation of B-NHL cells could be induced in the culture system. However, CDw32-transfected murine fibroblasts most efficiently supported cell viability of B-NHL cells with an increase in cell survival by 114% compared to the control (P = 0.047). IL-4 alone also had a stimulatory effect on cell survival of B-NHL cells after 6 days. In contrast, the soluble recombinant CD40 ligand gp39 and the anti-CD40 mAbs mAb89 and EA-5 did not prolong cell survival. CDw32 transfectants blocked apoptosis of B-NHL cells efficiently from 67% in the control to 16% (P = 0.001). Reduction in apoptosis was accompanied by an elevated bcl-2 protein expression. IL-4 or mAb89 did not further reduce apoptotic cell death in CDw32 transfectant-dependent cocultures. Our data underline the pivotal role of LTK- cells for cell survival of B-NHL cells in vitro. The efficient blockage of apoptosis associated with increased bcl-2 protein expression causes prolonged cell viability of the B-NHL cells.
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PMID:In vitro activation of low-grade non-Hodgkin's lymphoma by murine fibroblasts, IL-4, anti-CD40 antibodies and the soluble CD40 ligand. 936 19

The malignant B cells of non-Hodgkin's lymphoma (B-NHL cells) express peptides derived from tumor-specific antigens such as immunoglobulin idiotypes, and also express major histocompatibility complex antigens. However, they do not express co-stimulatory molecules, which likely contributes to their protection from host antitumor immunity. To stimulate NHL-specific immune responses, we attempted to transfer the human CD40 ligand (hCD40L) gene to B-NHL cells and enhance their co-stimulatory potential. We found that an adenoviral vector encoding human CD40L (AdhCD40L) was ineffective at transducing B-NHL cells because these cells lack the coxsackievirus B-adenovirus receptor and alpha(v) integrins. However, preculture of the B-NHL cells with the human embryonic lung fibroblast line, MRC-5, significantly up-regulated expression of integrin alpha(v)beta 3 and markedly increased their susceptibility to adenoviral vector transduction. After prestimulation, transduction with AdhCD40L increased CD40L expression on B-NHL cells from 1.3+/-0.2% to 40.8+/-11.9%. Transduction of control adenoviral vector had no effect. Expression of transgenic human CD40L on these CD40-positive cells was in turn associated with up-regulation of other co-stimulatory molecules including B7-1/-2. Transduced B-NHL cells were now able to stimulate DNA synthesis of autologous T cells. However, the stimulated T cells were unable to recognize unmodified lymphoma cells, a requirement for an effective tumor vaccine. Based on previous results in an animal model, we determined the effects of combined use of B-NHL cells transduced with AdhCD40L and AdhIL2 vectors. The combination enhanced initial T-cell activation and generated autologous T cells capable of specifically recognizing and killing parental (unmodified) B-NHL cells via major histocompatibility complex--restricted cytotoxic T lymphocytes. These findings suggest that the combination of CD40L and IL2 gene-modified B-NHL cells will induce a cytotoxic immune response in vivo directed against unmodified tumor cells.
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PMID:Transgenic expression of CD40L and interleukin-2 induces an autologous antitumor immune response in patients with non-Hodgkin's lymphoma. 1147 58

The mechanisms underlying the autonomous accumulation of malignant B cells remain elusive. We show in this study that non-Hodgkin's lymphoma (NHL) B cells express B cell-activating factor of the TNF family (BAFF) and a proliferation-inducing ligand (APRIL), two powerful B cell-activating molecules usually expressed by myeloid cells. In addition, NHL B cells express BAFF receptor, which binds BAFF, as well as transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and B cell maturation Ag (BCMA), which bind both BAFF and APRIL. Neutralization of endogenous BAFF and APRIL by soluble TACI and BCMA decoy receptors attenuates the survival of NHL B cells, decreases activation of the prosurvival transcription factor NF-kappaB, down-regulates the antiapoptotic proteins Bcl-2 and Bcl-x(L), and up-regulates the proapoptotic protein Bax. Conversely, exposure of NHL B cells to recombinant or myeloid cell-derived BAFF and APRIL attenuates apoptosis, increases NF-kappaB activation, up-regulates Bcl-2 and Bcl-x(L), and down-regulates Bax. In some NHLs, exogenous BAFF and APRIL up-regulate c-Myc, an inducer of cell proliferation; down-regulate p53, an inhibitor of cell proliferation; and increase Bcl-6, an inhibitor of B cell differentiation. By showing that nonmalignant B cells up-regulate BAFF and APRIL upon stimulation by T cell CD40 ligand, our findings indicate that NHL B cells deregulate an otherwise physiological autocrine survival pathway to evade apoptosis. Thus, neutralization of BAFF and APRIL by soluble TACI and BCMA decoy receptors could be useful to dampen the accumulation of malignant B cells in NHL patients.
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PMID:Lymphoma B cells evade apoptosis through the TNF family members BAFF/BLyS and APRIL. 1497 35

Two members of the NF-kappaB (nuclear factor kappaB)/Rel transcription factor family, NF-kappaB1 and NF-kappaB2, are produced as precursor proteins, NF-kappaB1 p105 and NF-kappaB2 p100 respectively. These are proteolytically processed by the proteasome to produce the mature transcription factors NF-kappaB1 p50 and NF-kappaB2 p52. p105 and p100 are known to function additionally as IkappaBs (inhibitors of NF-kappaB), which retain associated NF-kappaB subunits in the cytoplasm of unstimulated cells. The present review focuses on the latest advances in research on the function of NF-kappaB1 and NF-kappaB2 in immune cells. NF-kappaB2 p100 processing has recently been shown to be stimulated by a subset of NF-kappaB inducers, including lymphotoxin-beta, B-cell activating factor and CD40 ligand, via a novel signalling pathway. This promotes the nuclear translocation of p52-containing NF-kappaB dimers, which regulate peripheral lymphoid organogenesis and B-lymphocyte differentiation. Increased p100 processing also contributes to the malignant phenotype of certain T- and B-cell lymphomas. NF-kappaB1 has a distinct function from NF-kappaB2, and is important in controlling lymphocyte and macrophage function in immune and inflammatory responses. In contrast with p100, p105 is constitutively processed to p50. However, after stimulation with agonists, such as tumour necrosis factor-alpha and lipopolysaccharide, p105 is completely degraded by the proteasome. This releases associated p50, which translocates into the nucleus to modulate target gene expression. p105 degradation also liberates the p105-associated MAP kinase (mitogen-activated protein kinase) kinase kinase TPL-2 (tumour progression locus-2), which can then activate the ERK (extracellular-signal-regulated kinase)/MAP kinase cascade. Thus, in addition to its role in NF-kappaB activation, p105 functions as a regulator of MAP kinase signalling.
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PMID:Functions of NF-kappaB1 and NF-kappaB2 in immune cell biology. 1521 41

There is mounting evidence that innate and adaptive immunity are critical for periodontal disease-mediated bone resorption. These studies examined the role of B and CD4 T cells in adaptive immunity of rats infected with Aggregatibacter actinomycetemcomitans (Aa). Sprague-Dawley male rats were fed Aa-containing mash or control-mash for 2 weeks. B and CD4 T cells were obtained from draining lymph nodes at 2, 4 and 12 weeks, postinoculation. Quantitative polymerase chain reaction-based messenger RNA expression was conducted for 89 cytokine family genes. Disease-relevance of the differentially expressed genes was assessed using a biological interaction pathway analysis software. B and CD4 T cells of Aa-infected rats increased and were activated, resulting in enhanced isotype-switched serum immunoglobulin G by 2 weeks postinoculation. Bone resorption was evident 12 weeks after Aa-feeding. In B cells, interleukin-2 (IL-2), macrophage-inhibiting factor, IL-19, IL-21, tumor necrosis factor (TNF), CD40 ligand (CD40L), CD70, bone morphogenetic protein 2 (BMP2), BMP3, and BMP10 were upregulated early; while IL-7, Fas ligand (FasL), small inducible cytokine subfamily E1, and growth differentiation factor 11 (GDF11; BMP11) were upregulated late (12 weeks). BMP10 was sustained throughout. In CD4 T cells, IL-10, IL-16, TNF, lymphotoxin-beta (LTbeta), APRIL, CD40L, FasL, RANKL and osteoprotegerin were upregulated early, whereas IL-1beta, IL-1RN, IL-1F8, IL-24, interferon-alpha1, GDF11 (BMP11), and GDF15 were upregulated late (12 weeks). Adaptive immunity appears crucial for bone resorption. Several of the deregulated genes are, for the first time, shown to be associated with bone resorption, and the results indicate that activated B cells produce BMP10. The study provides a rationale for a link between periodontal disease and other systemic diseases.
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PMID:Adaptive immune response in osteoclastic bone resorption induced by orally administered Aggregatibacter actinomycetemcomitans in a rat model of periodontal disease. 2061 1


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