Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monocyte-induced cell-cytotoxicity has been implicated in the mechanism of suppression of normal haematopoietic progenitors in chronic myeloid leukemia (CML). We examined here the in vitro effect of CML-derived and normal peripheral blood (PB) monocytes on short- and long-term cultured haematopoietic progenitor cells. Short-term coculture (5 days) of CML or normal monocytes with CML or normal peripheral blood mononuclear cells (PBMNC)/CD34+ cells as targets resulted in a significant inhibition of colony-forming cell (CFC) growth. Coculture conditioned medium (CCM) from 5-days cocultures of normal or CML CD14+ monocytes with CD34+ cells were likewise inhibitory to CFC. In 5-week long-term cocultures of monocytes in direct contact with normal bone marrow (BM) progenitors, CML monocytes reduced the proportion of long-term cultured CFC (LTC-CFC) significantly to 52% of the controls, while normal monocytes had a less pronounced inhibitory effect (89% of the controls) on LTC-CFC. Reduction of LTC-CFC was great when CML monocytes and target cells were separated by a transwell membrane as compared to control cultures in the absence of CD14+ cells (53.5 vs. 9%). CCM from 5-week cocultures of normal or CML CD14+ monocytes with CD34+ progenitors from bone marrow (BM) cells were also inhibitory to CFC. No difference in cytokine levels for TNF-alpha, IFN-gamma, G-CSF, IL-10, IL-6 was detectable between CML CD14+ CCM and control CCM derived from short- and long-term cocultures. Our results suggest that CML monocytes may play a role in the inhibition of normal haematopoiesis through a yet not defined soluble factor supporting the expansion of the malignant clone in CML.
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PMID:CD14+ peripheral blood mononuclear cells from chronic myeloid leukemia and normal donors are inhibitory to short- and long-term cultured colony-forming cells. 1073 4

Chronic myelogenous leukemia (CML) is a disorder of the hematopoietic stem cell that results in malignant expansion of myeloid cells with a cytogenetic abnormality, the translocation between chromosomes 9 and 22 known as the Philadelphia chromosome. Treatment with IFN-alpha has proven to be an effective therapy, inducing cytogenetic remission in CML patients. However, it is unknown whether IFN-alpha can restore normal immune function for patients who achieve a complete cytogenetic remission. To address this question, we used a method of intracellular staining and flow cytometric analysis to ascribe the syntheses of Th1 or Th2 cytokines to T-cell subsets of patients in chronic, in accelerated, and in blast crisis phases as well as patients who had achieved a complete cytogenetic remission with IFN-alpha. We assessed the cytoplasmic synthesis of cytokine in phorbol ester (phorbol 12-myristate 13-acetate)-activated CD4+ and CD8+ T-cell subsets of 81 patients with various stages of CML and 21 normal controls. The percentages of CD4+ and CD8+ T cells from patients in chronic, in accelerated, and in blast crisis phases that synthesized Th1 cytokines interleukin (IL)-2, IFN-gamma, and tumor necrosis factor-alpha were significantly lower than those of remission patients and normal controls. Conversely, the percentages of CD4+ and CD8+ T cells of patients in chronic, in accelerated, and in blast crisis phases of CML preferentially synthesized the Th2 cytokine IL-10. Patients who achieved a durable complete cytogenetic remission for >2 years without maintenance IFN-alpha therapy restored their preference for a Th1 cytokine profile that is necessary for efficient cytotoxic T-cell function.
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PMID:Restoration of Th1 cytokine synthesis by T cells of patients with chronic myelogenous leukemia in cytogenetic and hematologic remission with interferon-alpha. 1081 85

Interferon (IFN) is an effective treatment for chronic myeloid leukemia (CML) in chronic phases, and a number of in vitro antileukemic effects of IFN on CML cells have been reported. The transfer of cytokine genes into tumor cells is reportedly a valuable approach to improve the antitumor activity of cytokines in various models. We first investigated the possibility of transducing CML cells with the retroviral vectors LIalpha2SN and LIgammaSN, encoding the IFN-alpha2 and IFN-gamma genes, respectively, and with the bicistronic vector LIalpha2IrIgammaSN coexpressing the IFN-alpha2 and IFN-gamma genes. We then analyzed the effects of IFN-alpha2 and IFN-gamma produced alone or simultaneously on the proliferation of CML cells. We optimized the transduction efficiency by using the CML-derived K562 cell line. We then introduced IFN genes into CML CD34+ cells. Secretion of IFN-alpha and IFN-gamma was demonstrated in K562 and CML CD34+ cells transduced with the different vectors. The MHC class I antigens were overexpressed in both K562 and CML CD34+ transduced cells. Inhibition of the proliferation of LIalpha2IrIgammaSN-transduced CML cells was greater than with the LIalpha2SN and the LIgammaSN-transduced CML cells. We demonstrate an additive effect of IFN-alpha and IFN-gamma on the inhibition of K562 and CML CD34+ cell proliferation.
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PMID:Retroviral coexpression of IFN-alpha and IFN-gamma genes and inhibitory effects in chronic myeloid leukemia cells. 1088 14

Coeliac disease (CD) is caused by a CD4 T helper cell type 1 (Th1) response in the small intestinal mucosa to dietary gluten. As the major Th1 inducing cytokine, interleukin 12, is undetectable in CD gut mucosa, the mechanism by which Th1 effector cells are generated remains unknown. Interferon (IFN) alpha, a cytokine capable of promoting IFN-gamma synthesis, has been implicated in the development of Th1 mediated immune diseases. Here we report a case of CD-like enteropathy in a patient receiving IFN-alpha for chronic myeloid leukaemia. Morphological assessment of duodenal biopsies taken from the patient showed total villous atrophy, crypt cell hyperplasia, and a high number of CD3+ intraepithelial lymphocytes. Both antigliadin antibodies and antiendomysial antibodies were positive. RNA analysis revealed pronounced expression of IFN-gamma. Withdrawal of gluten from the diet resulted in a patchy improvement in intestinal morphology, normalisation of laboratory parameters, and resolution of clinical symptoms. By western blot analysis, IFN-alpha protein was seen in the duodenal mucosa from untreated CD patients but not in controls. This was associated with marked expression of IFN-gamma protein in CD mucosa. Collectively, these results suggest a role for IFN-alpha in promoting Th1 responses to gluten.
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PMID:Role of interferon alpha in promoting T helper cell type 1 responses in the small intestine in coeliac disease. 1117 37

ELISPOT assays are increasingly used for a direct detection and quantification of single antigen-specific T cells in freshly isolated peripheral blood mononuclear cells (PBMC). They are particularly attractive for the monitoring of specific T lymphocyte responses in clinical trials assessing antigen-specific immunizations in patients with cancer or chronic viral infections. However, one major limitation for the broad clinical implementation of ELISPOT assays is the lack of an inexhaustible source of suitable HLA-matched antigen-presenting cells (APC). Currently available allogeneic or xenogeneic APC (such as the human lymphoid hybrid T2 or HLA-transfected insect cells) can either lead to strong background spot production by APC-reactive T lymphocytes or have a low antigen presentation capability. Both phenomena can prevent the detection of low frequency T cell responses in PBMC. In search of alternative APC for ELISPOT assays, the human chronic myelogenous leukemia cell line K562 that per se does not express HLA class I and class II molecules on the cell surface was transfected with the HLA-A*0201 gene. Clonal HLA-A*0201-expressing K562 (K562/A*0201) cells were able to process and present endogenously expressed and exogenously loaded melanoma peptide antigens to HLA-A*0201-restricted cytolytic T lymphocyte clones in cytotoxicity and IFN-gamma ELISPOT assays. K562/A*0201 cells were then used as APC in IFN-gamma spot assays to detect ex vivo CD8(+) T lymphocytes responsive to known HLA-A*0201-binding peptide epitopes derived from cytomegalovirus, Epstein-Barr virus, influenza virus and melanoma in PBMC from HLA-A*0201-positive donors. In the majority of cases, peptide-pulsed K562/A*0201 cells were similarly efficient in the ability to visualize single antigen-specific CD8(+) T lymphocytes when compared to T2 cells. However, in contrast to T2, background reactivity of CD8(+) T cells responsive to unpulsed K562/A*0201 was regularly found to be negligible, thereby enhancing the sensitivity of the ELISPOT assay, particularly in donors with strong anti-T2 reactivity. K562 cells transfected with HLA-A*0201 or other HLA genes can serve as standard APC for monitoring T lymphocyte responses against tumor and viral peptide antigens.
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PMID:The use of HLA-A*0201-transfected K562 as standard antigen-presenting cells for CD8(+) T lymphocytes in IFN-gamma ELISPOT assays. 1173 Aug 45

Mice lacking transcription factor interferon consensus sequence binding protein (ICSBP) develop a syndrome similar to human chronic myeloid leukemia and are immunodeficient. In order to define the molecular mechanisms responsible for the cellular defects of ICSBP(-/-) mice, we used bone marrow-derived macrophages (BMM) to identify genes deregulated in the absence of ICSBP. Here, we report that disabled-2 (Dab2), a signal phosphoprotein, is transcriptionally up-regulated and accumulates in the cytoskeleton/membrane fraction of ICSBP(-/-) BMM. Moreover, our results revealed Dab2 as a novel IFN-gamma-response gene. Both ICSBP and the Ets-transcription factor PU.1 bind to the Dab2 promoter, whereby ICSBP represses PU.1-induced Dab2 promoter transactivation in vitro. Notably, repression of Dab2 expression by ICSBP is also found in myeloid progenitors. Overexpression of Dab2 leads to accelerated cell adhesion and spreading, accompanied by enhanced actin fiber formation. Furthermore, cell adhesion induces transient Dab2 phosphorylation and its translocation to the cytoskeletal/membrane fraction. Our results identify a novel role of Dab2 as an inducer of cell adhesion and spreading, and strongly suggest that the up-regulation of Dab2 contributes to the hematopoietic defect seen in ICSBP(-/-) mice.
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PMID:Disabled-2 is transcriptionally regulated by ICSBP and augments macrophage spreading and adhesion. 1182 14

P-glycoprotein (Pgp) and vaults are associated with multidrug resistance in tumor cells, but their physiological functions are not yet clear. Pgp, the prototypical transmembrane transporter molecule, may also facilitate the migration of skin dendritic cells (DC). Vaults--ribonucleoprotein cell organelles, frequently overexpressed in Pgp-negative drug-resistant tumor cells--have also been associated with intracellular transport processes. Given the pivotal role of DC in dealing with exposure to potentially harmful substances, the present study was set out to examine the expression of Pgp and vaults during differentiation and maturation of DC. DC were obtained from different sources, including blood-derived monocytes, CD34(+) mononuclear cells, and chronic myeloid leukemia cells. Whereas flow cytometric and immunocytochemical analyses showed slightly augmented levels of Pgp, up-regulation of vault expression during DC culturing was strong, readily confirmed by Western blotting, and independent of the source of DC. In further exploring the functional significance of vault expression, it was found that supplementing DC cultures with polyclonal or mAbs against the major vault protein led to lower viabilities of LPS- or TNF-alpha-matured monocytes-DC. Moreover, expression of critical differentiation, maturation, and costimulatory molecules, including CD1a and CD83, was reduced and their capacity to induce Ag-specific T cell proliferative and IFN-gamma release responses was impaired. These data point to a role for vaults in both DC survival and functioning as APC.
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PMID:Up-regulation of drug resistance-related vaults during dendritic cell development. 1182 84

Interferon (IFN) consensus sequence binding protein (ICSBP)/IFN regulatory factor (IRF)-8 is an IFNgamma-inducible transcription factor of the IRF family and regulates transcription through multiple target DNA elements, such as IFN-stimulated response element (ISRE), Ets/IRF composite element, and IFN-gamma activation site (GAS). ICSBP(-/-) mice are immunodeficient and susceptible to various pathogens. They have defects in the macrophage function, including the ability to induce interleukin-12 (IL-12) p40 and some IFN-gamma-responsible genes. In addition, ICSBP(-/-) mice develop a chronic myelogenous leukemia (CML)-like syndrome, where a systemic expansion of granulocytes is followed by a fatal blast crisis. ICSBP(-/-) mice harbor an increased number of myeloid progenitor cells, and the -/- progenitors preferentially give rise to granulocytes, although they cannot efficiently generate another descendant of the myeloid lineage, macrophages. Studies with myeloid progenitor cells have shown that ICSBP drives their differentiation toward macrophage, whereas it inhibits granulocyte differentiation. Furthermore, myeloid cells from ICSBP(-/-) mice are resistant to apoptosis. These results illustrate the mechanism by which the loss of ICSBP leads to immunodeficiency and CML-like syndrome and suggest ICSBP's critical role in the development of myeloid cells.
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PMID:ICSBP/IRF-8: its regulatory roles in the development of myeloid cells. 1184 85

To observe the proliferation of T lymphocytes stimulated by CML and AML cells which were induced by rhGM-CSF and rhIL-4, and the secretion of IFN-gamma from proliferated T lymphocytes, the expression of CD80, CD86 and HLA-DR on CML and AML cells induced by GM-CSF and IL-4 was assayed by flow cytometry in vitro. Then one-way mixed lymphocyte reaction was carried out, with induced leukemia cells as stimulating cells and auto-T lymphocytes as reactive cells. The secretion of IFN-gamma from T lymphocytes was determined by double antibody sandwich ELISA. The results showed that GM-CSF and IL-4 significantly upregulated the expression of CD80, CD86 and HLA-DR on CML cells and CD80 and CD86 on AML cells, which could stimulate the T lymphocyte proliferation and high secretion of IFN-gamma (in CML group) of autologous T lymphocytes. It is concluded that the CML and AML cells induced by GM-CSF and IL-4 have the ability to present tumor specific antigen to auto-T lymphocyte.
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PMID:[Proliferation and IFN-gamma secretion of autologous T lymphocytes stimulated by myeloid leukemia cells induced with rhGM-CSF and rhIL-4]. 1251 7

The role of T cells in eradicating leukemic cells has been well demonstrated for chronic myeloid leukemia (CML). Type 1 (T1) T-cell cytokines play a major role in this antileukemic immune effect. Studies in cancer patients have demonstrated a decreased T1 cytokine production, measured by enzyme-linked immunosorbent assay (ELISA), in cultures of peripheral blood mononuclear cells. This observation of malignancy-related suppressed T1 cytokines also occurs in untreated chronic-phase (CP) CML, raising the question of the influence of different CML treatment regimens on this immunosuppression. Intracellular flow cytometry (ICF) has facilitated the evaluation of cytokines on a single-cell level. This study analyzed T1 (interferon-gamma) cytokine production in purified peripheral blood T cells by ICF, comparing different therapy approaches for CML. Twenty-one newly diagnosed CP CML patients were compared with 24 patients treated with interferon-alpha (IFN-alpha) and to 30 allogeneic bone marrow transplant (BMT) recipients (BCR-ABL negative by reverse-transcriptase polymerase chain reaction, and free of, or having only limited graft-versus-host disease at the time of study). Thirty-seven healthy controls were included. Our results showed a significantly decreased T-cell IFN-gamma synthesis in CP CML patients in relation to healthy controls (P = 0.0007). Treatment with IFN-alpha resulted in a shift from immunosuppression--documented for the group of untreated patients--to immunopotentiation, with an increase of T-cell IFN-gamma production (P = 0.0266). Notably, BMT enhanced IFN-gamma production of T cells to a level not only exceeding untreated patients (P < 0.0001) but also healthy volunteers (P < 0.0001). The observation of T1 cytokine up-regulation with IFN-alpha therapy indicates that enhanced T-cell function may be achievable in patients with CML, even in the absence of an allo-response.
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PMID:Intracellular cytokine analysis of interferon-gamma in T cells of patients with chronic myeloid leukemia. 1260 98


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