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

Some of the recent advances in our knowledge of immune recognition have provided new tools to circumvent or reverse some of the major disadvantages of allogeneic bone marrow transplantation (BMT). The pretransplant conditioning regimen produces a major defect in the immune system that greatly favors the occurrence of life-threatening infections, caused particularly by Epstein-Barr virus and cytomegalovirus. However, adoptive transfer of virus-specific cytotoxic T lymphocytes can reconstitute specific immunity and/or cure viral disease in immunocompromised post-BMT patients. The other major drawback of allogeneic BMT is graft-versus-host disease (GVHD). Although potentially detrimental, it is closely associated with an antileukemia reaction (graft-versus-leukemia, GVL). The most direct evidence of the GVL effect has been provided by the efficacy of donor leukocyte infusions (DLI). DLI can induce long-lasting remissions, especially in patients with chronic myeloid leukemia who relapse post-BMT. Although allogeneic cell therapy should still be considered a "naive" form of immunotherapy, work in progress on the identification of leukemia-specific antigens will improve the outcome and enlarge its applications.
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PMID:Adoptive immunotherapy following allogeneic bone marrow transplantation. 950 67

We have developed culture conditions for the efficient expansion of cytotoxic effector cells from peripheral blood mononuclear cells (PBMNCs) by the timed addition of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and the monoclonal antibody (MoAb) OKT3. These cells, termed cytokine-induced killer (CIK) cells, are composed primarily of T cells, and the population of cells with the greatest cytotoxic activity is an otherwise rare population of CD3(+)CD56(+) cells that expand dramatically under these culture conditions. CIK cells were expanded from PBMNCs from 13 patients with chronic myeloid leukemia (CML). These cultures contained a variable number of T cells at the start of the culture (median 44%, range 1% to 64%), yet after 21 to 28 days of culture, virtually all of the cells were CD3(+) T cells (median 97%, range 90% to 99%). The CD3(+)CD56(+) subset of cells expanded significantly (median 25-fold, range 2.2- to 525-fold). CIK cells from all patients showed cytotoxicity against the tumor cell lines OCI-LY8 and K562. In four patients the expanded CIK cells suppressed colony growth of autologous CML blast cells and myeloid progenitor cells. Allogeneic CIK cells from normal donors also suppressed CML colony growth but did not inhibit growth of normal hematopoietic colonies. Twelve of the 13 cultures were exclusively composed of Philadelphia (Ph)-negative cells and one culture had 1 out of 20 Ph-positive metaphases after 4 weeks in culture. Intracellular cytokine production was assayed by fluorescence-activated cell sorter (FACS), and the expanded T-cell cultures produced IL-2, IFN-gamma, and tumor necrosis factor-alpha (TNF-alpha), but not IL-4. Both the CD4(+) and CD8(+) subsets secreted this cytokine profile. To test the in vivo activity of the expanded CIK cells, CML was engrafted into severe combined immunodeficiency disease (SCID) mice using matrigel. After 4 weeks, 4 x 10(7) autologous CIK cells were injected intravenously by tail vein injection into groups of mice, and the animals were sacrificed after a total of 18 weeks. Bcr-abl was detected in the bone marrow or spleen of 5 out of 6 control mice and only 2 out of 13 mice who received the autologous CIK cells (P = .02). In an additional series of animals, the mice did not engraft with CML but instead developed large human Epstein-Barr virus-associated lymphomas by 12 weeks. The mice who received autologous CIK cells at 4 weeks had either no tumor (5) or small tumors (5), whereas all 10 mice that received CIK cells at week 8 developed lymphomas; however, these were not as large as in the 10 control mice who did not receive CIK cells (P = . 03). This study shows that CIK cells, which are Ph chromosome-negative, can be expanded from patients with CML and have potent in vitro and in vivo efficacy against autologous tumor cells.
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PMID:Expansion of Philadelphia chromosome-negative CD3(+)CD56(+) cytotoxic cells from chronic myeloid leukemia patients: in vitro and in vivo efficacy in severe combined immunodeficiency disease mice. 978 69

Until recently, the only cure for relapse after allogeneic bone marrow transplantation (BMT) has been a second BMT. Recently, infusions of leukocytes collected from the original transplant donor have been used to induce a direct graft-versus-leukemia (GVL) reaction in patients with relapsed disease. Adoptive immunotherapy with donor leukocyte infusions (DLI) results in complete remission for 60-80% of patients with relapsed chronic-phase CML; therapy is also effective for relapse of diseases other than CML, although response rates are lower. Adoptive immunotherapy induces remissions for the majority of patients with post-transplantation Epstein-Barr virus-related lymphomas and other viral-associated illnesses. The extraordinary success of DLI demonstrates that it is now possible to harness the GVL potential of the human immune system for clinical benefit. The necessary effector cells and target antigens required for GVL reactivity are poorly defined but are the subject of intensive investigation. Future trials will investigate strategies that retain and enhance the GVL effects while limiting toxicity from this therapy, and they may define methods of successful allogeneic adoptive immunotherapy outside the setting of allogeneic BMT.
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PMID:The graft-versus-leukemia effects of allogeneic cell therapy. 1007 84

Chromosomal aberrations and inactivation of tumour suppressor genes are frequent in acute leukaemia. To determine whether the FHIT gene is involved in the development of leukaemia, we examined the FHIT transcript in 65 leukaemia cell lines, 5 fresh acute leukaemia patients at diagnosis and in complete remission, normal peripheral blood lymphocytes obtained from 14 healthy volunteers and Epstein-Barr (EB) virus transformed 5 B-cell lines (EB-lines), using nested reverse transcription-polymerase chain reaction and direct sequencing. The transcripts were classified into 4 patterns: pattern I revealed the normal transcripts only, pattern II the altered transcripts in addition to the normal transcripts, pattern III the altered transcripts without the normal transcripts and pattern IV an absence of normal and altered FHIT transcripts. Nineteen cell lines were classified as pattern I, 32 as pattern II, 2 as pattern III and 12 as pattern IV. The frequency of loss of FHIT expression (pattern III or IV) varied in each type of leukaemia cell line; the order ranked from the highest incidence was acute myeloid leukaemia (AML), T-cell acute lymphoblastic leukaemia (T-ALL), B-precursor ALL, B-ALL, and chronic myeloid leukaemia (CML). No genomic rearrangement was found in any samples examined. All of 5 patients showed same pattern II FHIT transcripts at 2 different stages of the disease. All normal peripheral blood lymphocytes and EB-lines were classified as pattern I or II. Our results suggested that patterns III and IV of FHIT transcripts might be associated with the development of a subset of leukaemia, while pattern II which has so far been reported as an aberrant transcript in varieties of malignant tumours might not be associated with leukaemogenesis.
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PMID:Pattern of FHIT gene expression in normal and leukaemic cells. 1036 36

Peptides corresponding to the fusion site in 210 kD BCR-ABL protein b3a2 (p210b3a2) were previously shown to bind to several HLA class I and II alleles. We have found that b3a2 peptide-specific CD4-positive T-helper cells were able to recognize p210b3a2-positive chronic myelogenous leukemia (CML) blasts in a DR4 restricted manner. Until now, there were no reports of b2a2 breakpoint-specific human T-cell responses. Here we show that repetitive stimulation of T lymphocytes with a 17mer peptide covering the fusion region in p210b2a2 also leads to specific T-cell responses. CD4 and CD4/CD8 double-positive clones obtained from a b2a2 peptide-specific cell line were cytotoxic and proliferative in an HLA-DR2a (DRB5*0101) restricted fashion. Autologous Epstein-Barr virus (EBV) transformed cells, expressing BCR-ABL(b2a2) on transfection, and allogeneic HLA-DR matched p210b2a2-positive cells from CML patients were, however, not lysed. BCR-ABL peptide-specific T-cell clones did respond to autologous EBV cells transfected with invariant chain (li) cDNA in which the HLA class II-associated invariant chain peptide (CLIP) was replaced by a BCR-ABL b2a2 fusion oligonucleotide sequence, illustrating the potential of these T cells to recognize an endogenous BCR-ABL(b2a2) ligand.
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PMID:A BCR-ABL oncoprotein p210b2a2 fusion region sequence is recognized by HLA-DR2a restricted cytotoxic T lymphocytes and presented by HLA-DR matched cells transfected with an Ii(b2a2) construct. 1041 96

Adoptive cellular immunotherapy with donor leukocytes of patients submitted to allogenic stem cell transplantation has had significant success in the past few years, especially in the treatment of primary disease relapse and in the prevention and treatment of some post-transplant infectious complications. Most patients treated with donor leukocytes had a relapse of chronic myelogenous leukemia, which was successfully re-induced into remission. The most significant toxicities of this treatment are the development of graft versus host disease and marrow aplasia. Three strategies were developed to limit the former: the infusion of graded doses of donor leukocytes, the depletion of CD8+ cells and the transfer of donor leukocytes transvected with a timidine kinase gene, which renders these cells sensitive to gancyclovir. The post-transplant infectious complications treated successfully with donor leukocytes were Epstein-Barr virus-induced lymphoproliferative disorders and cytomegalovirus infection. The former, arising most frequently in recipients of unrelated and/or mismatched T-cell depleted grafts, were treated with donor unseparated leukocytes or Epstein-Barr virus-specific T-cells. Cytomegalovirus infection in the early post-transplant period was largely prevented by the infusion of virus-specific T-cell clones, which restored donor-specific immunity to cytomegalovirus in the recipient.
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PMID:[Donor leukocyte infusion after allogeneic stem cell transplantation]. 1070 63

Unless they undergo transplantation, all patients with chronic myeloid leukemia (CML) will eventually develop a late phase of acute blast crisis (ABC). Although additional chromosomal abnormalities to the Philadelphia (Ph) chromosome may herald ABC in many CML cases, the mechanisms leading to this fatal event are obscure. Viral etiology, including the Epstein-Barr virus (EBV) has never been implicated in the pathogenesis of ABC in CML. Iloprost is an analogue of epoprostenol (prostacyclin; PGI2) commonly used for the treatment of peripheral vascular diseases and acts via inhibition of platelet activation, and by vasodilation. A case of ABC with blasts of undetermined lineage showing EBV infection in a male patient with Ph positive CML is described here. This unusual event developed during a course of treatment with the prostacyclin analogue, iloprost administered for vasculopathic leg ulcers. The proliferating blasts stained positively by immunohistochemistry only for the leukocyte common antigen (LCA/CD-45), and the EBV-latent membrane protein 1 (LMP-1). The only chromosomal abnormality detected by cytogenetic analysis was the conventional Ph-chromosome. It is suggested that ABC in this case of CML, was associated with EBV-activated blasts of undetermined lineage.
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PMID:Acute blast crisis with EBV-infected blasts, in a patient with chronic myeloid leukemia, and vasculitis. 1075 95

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

Homogeneous immunoglobulins are frequently detected in the serum of patients undergoing allogeneic bone marrow transplantation (BMT). The aim of the present study was to further characterize the incidence of this phenomenon and its correlations with laboratory and clinical data. Serum samples were gathered from 29 patients undergoing allogeneic or syngeneic BMT for chronic myeloid leukemia (CML), and serial protein (IgG, IgA and IgM) quantification, electrophoresis and immunofixation were performed. Transient mono- or oligoclonal gammopathies were observed in 23 out of 29 patients between days 20 and 1,750 following transplantation. The presence of homogeneous immunoglobulins was not correlated with the following clinical parameters: graft-versus-host disease, bacterial sepsis, Epstein-Barr virus or cytomegalovirus infection or invasive fungal infection. Therefore, the development of mono- or oligoclonal immunoglobulins may represent a complex disorder of B cell regeneration which may be caused by an intrinsic B cell defect, or a failure in the regenerating T cell system, or both, manifesting itself in a restricted antibody diversity after allogeneic BMT.
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PMID:Homogeneous immunoglobulins following allogeneic bone marrow transplantation. 1271 21

Poor immune reconstitution after haploidentical stem cell transplantation results in a high mortality from viral infections and relapse. One approach to overcome this problem is to selectively deplete the graft of alloreactive cells using an immunotoxin directed against the activation marker CD25. However, the degree of depletion of alloreactive cells is variable following stimulation with recipient peripheral blood mononuclear cells (PBMCs), and this can result in graft versus host disease (GVHD). We have refined this approach using recipient Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) as stimulators to activate donor alloreactive T cells. Our studies demonstrate that allodepletion with an anti-CD25 immunotoxin following stimulation with HLA-mismatched host LCLs more consistently depleted in vitro alloreactivity than stimulation with host PBMCs, as assessed in primary mixed lymphocyte reactions (MLRs). Allodepletion using this approach specifically abrogates cytotoxic T-cell responses against host LCLs. In interferon-gamma (IFN-gamma) enzyme-linked immunospot (ELISPOT) assays, antiviral responses to adenovirus and cytomegalovirus (CMV) were preserved following allodepletion. Likewise, using HLA-A2-pp65 tetramers, we have shown that the frequency of CMV-specific T cells is unaffected by allodepletion. Moreover, the donor anti-EBV response is partially retained by recognition of EBV antigens through the nonshared haplotype. Finally, we studied whether allodepletion affects the response to candidate tumor antigens in myeloid malignancies. Using HLA-A2-PR1 tetramer analysis, we found that the frequency of T cells recognizing the PR1 epitope of proteinase 3 was not significantly different in allodepleted and unmanipulated PBMCs from patients with chronic myeloid leukemia (CML) undergoing transplantation. Based on these data, we have embarked on a phase 1 clinical trial of addback of allo-LCL-depleted donor T cells in the haplo-identical setting.
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PMID:Selective depletion of donor alloreactive T cells without loss of antiviral or antileukemic responses. 1276 37


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