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)

The goal of this work was to optimize dendritic cell (DC) preparations obtained from patients suffering from chronic myeloid leukemia (CML) and compare them with DC prepared from normal CD14+ mononuclear cells (MNC). We studied normal DC and bcr-abl+ leukemic DC (CML-DC) yields, expression of membrane molecules, differentiation status, and ability to stimulate T cells. We isolated DC precursors from PBMC by CD14-specific immunoadsorption and cultured them for 7 days in GM-CSF and IL-4, followed by a 3-day incubation to fully differentiate the cells. We evaluated cultures of CML-DC using RPMI 1640 medium supplemented with FBS and X-VIVO 15 medium containing human AB serum. In contrast to cells matured in RPMI 1640, virtually all cells incubated in X-VIVO 15 expressed CD83, a marker of mature DC. CML-DC and normal DC were indistinguishable in expression of CD83, resulting in the highest percentage reported so far. The yields of normal DC and CML-DC from CD14+ cells were indistinguishable. The percentage of bcr-abl+ cells in PBMC varied among patients between 65% and 97% and the final CML-DC preparations were >98% bcr-abl+ the highest purity of bcr-abl+ cells to date. Normal DC and CML-DC were equally effective in stimulating proliferation of allogeneic and autologous T cells. These techniques provide highly enriched, mature, functional CML-DC.
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PMID:Optimizing preparation of normal dendritic cells and bcr-abl+ mature dendritic cells derived from immunomagnetically purified CD14+ cells. 1073 77

We report a method to generate dendritic cells (DC) from frozen leukapheresis products of patients with chronic myeloid leukemia (CML), using sterile culture bags and serum-free culture medium, ie conditions feasible for re-infusion into the patient as part of immunotherapeutic protocols. Leukapheresis products were stored from harvests performed either at diagnosis (13 patients) or after chemotherapy with subsequent granulocyte colony stimulating factor (G-CSF) administration (9 patients), for Peripheral Blood Stem Cell (PBSC) collections. In the presence of optimal concentrations of GM-CSF (50 ng/ml) and IL-4 (40 ng/ml) CML progenitors differentiated on day 7 and 14 of culture to DC, expressing CD1a,HLA-DR and CD86 surface antigens. Mature DCs exhibited on average 12-fold higher allo-stimulatory capacity for CD4+ and CD8+ cells compared to non-cultured PBMC in mixed lymphocyte reaction (MLR). Only DCs obtained from CML patients at diagnosis exhibited bcr/abl fusion gene when tested by fluorescent in situ hybridization (FISH). CD34-selection on leukapheresis products from diagnosis (7 patients) resulted in later maturation of DCs (after 14-15 d), compared to the nonselected PBMC. CD34-selection significantly increased the DC growth, and improved the allo-stimulatory capacity in MLR (on average on day 14, 3.5- and 2.3-fold, respectively). Large differences were observed between individual patients and different leukapheresis products from the same patient. Our report demonstrates the possibility to generate ex vivo autologous functionally active DC in CML in a way that allows their clinical application as immunotherapeutic agents.
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PMID:Generation of dendritic cells from peripheral blood of patients at different stages of chronic myeloid leukemia. 1111 5

Although interferon alpha (IFN-alpha) is able to induce haematological remission in 60-80% of patients with chronic myeloid leukaemia (CML) in early chronic phase, major cytogenetic remissions are only achievable in 30-40%. Recent clinical data suggest that the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) to IFN-alpha therapy can significantly improve the cytogenetic response in some patients, although the mechanism remains unknown. We hypothesized that the combination of GM-CSF and IFN-alpha induces the differentiation of dendritic cells, which subsequently stimulates a specific anti-leukaemic response. Monocytes from CML patients were cultured in GM-CSF and interleukin (IL)-4 (GM/IL-4)or in GM-CSF and IFN-alpha (GM/IFN-alpha). After 7 d, the number of cells exhibiting typical antigen-presenting cell (APC) morphology was equal in both groups, and fluorescence in situ hybridization (FISH) analysis confirmed that the APCs generated with GM/IFN-alpha were of leukaemic origin. Phenotypically, both sets of APCs expressed typical surface markers; however, CD86, CD83, CD11c, HLA-ABC and HLA-DR expression was significantly higher in the GM/IFN-alpha APCs, whereas CD1a expression was significantly lower. In mixed lymphocyte reactions (MLR), GM/IFN-alpha APCs stimulated the proliferation of allogeneic T cells significantly better than GM/IL-4 APCs. However, both groups of APCs stimulated autologous T-cell proliferation equally. Finally, we assessed the ability of GM/IFN-alpha APCs to induce a leukaemia-specific cytotoxic T-cell response. Some samples generated cytotoxic T lymphocytes (CTLs) that specifically lysed bcr-abl-positive target cells. These data show that the combination of GM-CSF and IFN-alpha, when used in vitro, induces the differentiation of malignant APCs with potent T-cell stimulatory capacity. Although there is no in vivo evidence to support these findings, it is possible that, when administered to CML patients, GM-CSF in combination with IFN-alpha results in the generation of highly stimulatory leukaemic APCs.
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PMID:Interferon alpha in combination with GM-CSF induces the differentiation of leukaemic antigen-presenting cells that have the capacity to stimulate a specific anti-leukaemic cytotoxic T-cell response from patients with chronic myeloid leukaemia. 1112 8

Chronic myelogenous leukemia (CML) may be amenable to cell-based adoptive immunotherapy, as suggested by the graft-versus-leukemia effect of bone marrow transplantation and the therapeutic benefit of donor leukocyte infusions. Specific adoptive immunotherapy without bone marrow transplantation might be more effective and less cost-intensive. Professional antigen-presenting cells, the dendritic cells, from patients with CML are derived from the malignant clone and may stimulate antileukemia T-cell responses. Autologous T cells may also be able to recognize tumor antigens on CML cells directly. Here, the authors show that CD4 and CD8 T-cell responses to autologous CML cells can be generated in vitro rapidly and effectively by performing modified autologous mixed lymphocyte/tumor cell cultures (MLTC) in serum-free medium in the presence of cytokines known to support dendritic cell differentiation. MLTC-sensitized T cells secreted large amounts of the type 1 cytokine interferon-gamma, as well as interleukin (IL)-2. However, they also secreted a variety of other cytokines, including the type 2-subtype cytokine IL-13 but not the classic type 2 cytokines IL-4, IL-5, and IL-10. Monoclonal populations of CML-specific CD4 cells could be derived from these lines in limited numbers but showed markedly enhanced reactivity. This suggests that CML-specific T cells are relatively rare in these autologous MTLC-derived sensitized populations, but that their isolation and propagation would yield much more potent antitumor effector cells for use in adoptive immunotherapy without the need for bone marrow transplantation.
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PMID:Generation of chronic myelogenous leukemia-specific T cells in cytokine-modified autologous mixed lymphocyte/tumor cell cultures. 1175 71

Evidence from allogeneic hematopoietic stem cell transplantation indicates a possible immune response against leukemia-associated antigens in patients with either acute myeloid leukemia (AML) or chronic myeloid leukemia (CML). However, autologous immune responses are less evident. We have developed a method using sequential modulation of growth factors (SMGF) to generate specific anti-AML T-cells from primary cultures of mononuclear cells (MNCs) from patients with AML. This culture method induces greater degrees of antigen presentation by inducing dendritic cell (DC) differentiation of AML in the presence of autologous lymphocytes, which are then expanded by interleukin (IL)-2 and costimulatory molecule ligation. MNCs consisting of 92.3% +/- 5.1% AML blasts and 3.4% +/- 3.2% CD3+ T-cells were obtained from AML patients (n = 12) and cultured in AIM-V medium with IL-4 and recombinant granulocyte-monocyte colony-stimulating factor. Recombinant IL-2 was added on day 8. On day 21, culture conditions were changed to anti-CD3/anti-CD28 monoclonal antibodies and IL-2. By day 42, 354 +/- 182-fold CD3+ T-cell expansion had occurred. Cytotoxic T-lymphocyte assays demonstrated that these T-cells caused significant lysis of autologous leukemia cells and AML cell lines, but not of cells of other lineages, in an HLA class I-dependent manner. Specific Vbeta subgroups (Vbeta3, -7, and -12a), possibly representing T-cell clones specific to AML-specific antigens, were expanded in the cultures of cells from 3 AML patients. SMGF can be used to induce and expand autologous T-cells with HLA class I-dependent antileukemia potential from the peripheral blood of AML patients. Adoptive transfer of these expanded T-cells to patients is a possible therapeutic approach for further study.
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PMID:Sequential modulation of growth factors: a novel strategy for adoptive immunotherapy of acute myeloid leukemia. 1243 51

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 purpose of this study was to investigate the function of dendritic cells derived from chronic myeloid leukemia (CML-DC). Mononuclear cells were prepared from bone marrow and peripheral blood of 24 patients with CML, and the DCs were obtained by incubation of MNCs with media containing GM-CSF, IL-4 and TNF-alpha. The phenotype of CML-DCs was identified by flow cytometry. FITC-dextran uptake, (3)H-TdR incorporation or MTT assay and lactate dehydrogenase release assay were used to detect uptake of exogenous antigen in immature DCs, the antigen presenting ability in mature DCs and specific cytotoxicity of CTL to leukemic cells, respectively. The DCs with high expression of CD1a, CD86, CD80, HLA-DR, CD54 and CD4 were obtained from marrow and blood of patients with CML. The uptake of FITC-DX was observed in early DCs. There was a potent stimulation to allo-MLR in DCs cultured for 7 - 10 days, and a lightly lower stimulation to auto-MLR. CML-DCs can induce the generation of specific cytotoxic T cells. These results suggest that CML-DCs are functional DCs with the ability to induce anti-leukemia effect.
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PMID:[The Function of Dendritic Cells Derived from Chronic Myeloid Leukemia] 1257 75

Chronic myelogenous leukemia (CML) is a malignant myeloproliferative disease arising from the clonal expansion of a stem cell expressing the bcr/abl oncogene. CML patients frequently respond to treatment with interferon-alpha (IFN-alpha), even though the mechanisms of the response remain unclear. In the present study, we evaluated the role of IFN-alpha in differentiation and activity of monocyte-derived dendritic cells (DCs) from CML patients as well as in modulation of the cell response to lipopolysaccharide (LPS). Treatment of CML monocytes with IFN-alpha and granulocyte-macrophage colony-stimulating factor (GM-CSF) resulted in the rapid generation of activated DCs (CML-IFN-DCs) expressing interleukin-15 (IL-15) and the antiapoptotic bcl-2 gene. These cells were fully competent to induce IFN-gamma production by cocultured autologous T lymphocytes and expansion of CD8(+) T cells. LPS treatment of CML-IFN-DCs, but not of immature DCs generated in the presence of IL-4/GM-CSF, induced the generation of CD8(+) T cells reactive against autologous leukemic CD34(+) cells. Altogether, these results suggest that (1) the generation of highly active monocyte-derived DCs could be important for the induction of an antitumor response in IFN-treated CML patients and (2) IFN-alpha can represent a valuable cytokine for the rapid generation of active monocyte-derived DCs to be utilized for vaccination strategies of CML patients.
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PMID:IFN-alpha promotes the rapid differentiation of monocytes from patients with chronic myeloid leukemia into activated dendritic cells tuned to undergo full maturation after LPS treatment. 1452 81

Dok1 is a common substrate of activated protein-tyrosine kinases. It is rapidly tyrosine-phosphorylated in response to receptor tyrosine activation and interacts with ras GTPase-activating protein and Nck, leading to inhibition of ras signaling pathway activation and the c-Jun N-terminal kinase (JNK) and c-Jun activation, respectively. In chronic myelogenous leukemia cells, it has shown constitutive phosphorylation. The N-terminal phosphotyrosine binding (PTB) domain of Dok1 can recognize and bind specifically to phosphotyrosine-containing motifs of receptors. Here we report the crystal structure of the Dok1 PTB domain alone and in complex with a phosphopeptide derived from RET receptor tyrosine kinase. The structure consists of a beta-sandwich composed of two nearly orthogonal, 7-stranded, antiparallel beta-sheets, and it is capped at one side by a C-terminal alpha-helix. The RET phosphopeptide binds to Dok1 via a surface groove formed between strand beta5 and the C-terminal alpha-helix of the PTB domain. The structures reveal the molecular basis for the specific recognition of RET by the Dok1 PTB domain. We also show that Dok1 does not recognize peptide sequences from TrkA and IL-4, which are recognized by Shc and IRS1, respectively.
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PMID:Structural basis for the specific recognition of RET by the Dok1 phosphotyrosine binding domain. 1460 33

Allogeneic bone marrow transplantation (alloBMT) is the only curative therapy for chronic myelogenous leukemia (CML). This success is explained by the delivery of high doses of antineoplastic agents followed by the rescue of marrow function and the induction of graft-versus-leukemia reaction mediated by allogeneic lymphocytes against host tumor cells. This reaction can also be induced by donor lymphocyte infusion (DLI) producing remission in most patients with CML who relapse after alloBMT. The immunological mechanisms involved in DLI therapy are poorly understood. We studied five CML patients in the chronic phase, who received DLI after relapsing from an HLA-identical BMT. Using flow cytometry we evaluated cellular activation and apoptosis, NK cytotoxicity, lymphocytes producing cytokines (IL-2, IL-4 and IFN-gamma), and unstimulated (in vivo) lymphocyte proliferation. In three CML patients who achieved hematological and/or cytogenetic remission after DLI we observed an increase of the percent of activation markers on T and NK cells (CD3/DR, CD3/CD25 and CD56/DR), of lymphocytes producing IL-2 and IFN-gamma, of NK activity, and of in vivo lymphocyte proliferation. These changes were not observed consistently in two of the five patients who did not achieve complete remission with DLI. The percent of apoptotic markers (Fas, FasL and Bcl-2) on lymphocytes and CD34-positive cells did not change after DLI throughout the different study periods. Taken together, these preliminary results suggest that the therapeutic effect of DLI in the chronic phase of CML is mediated by classic cytotoxic and proliferative events involving T and NK cells but not by the Fas pathway of apoptosis.
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PMID:Immunological effects of donor lymphocyte infusion in patients with chronic myelogenous leukemia relapsing after bone marrow transplantation. 1476 74


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