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)

In vitro studies have provided little consensus on the kinetic abnormality underlying the myeloid expansion of chronic myelogenous leukemia (CML). Transplantation of human CML cells into non-obese diabetic mice with severe immunodeficiency disease (NOD/SCID mice) may therefore be a useful model. A CML cell line (BV173) and peripheral blood cells collected from CML patients in chronic phase (CP), accelerated phase (AP), or blastic phase (BP) were injected into preirradiated NOD/SCID mice. Animals were killed at serial intervals; cell suspensions and/or tissue sections from different organs were studied by immunohistochemistry and/or flow cytometry using antihuman CD45 monoclonal antibodies (MoAbs), and by fluorescence in situ hybridization (FISH) for the BCR-ABL fusion gene. One hour after injection, cells were sequestered in the lungs and liver, but 2 weeks later they were no longer detectable in either site. Similar short-term kinetics were observed using 51Cr-labeled cells. The first signs of engraftment for BV173, AP, and BP cells were detected in the bone marrow (BM) at 4 weeks. At 8 weeks the median percentages of human cells in murine marrow were 4% (range, 1 to 9) for CP, 11% (range, 5 to 36) for AP, 38.5% (range, 18 to 79) for BP, and 54% (range, 31 to 69) for BV173. CP cells progressively infiltrated BM (21%) and spleen (6%) by 18 to 20 weeks; no animals injected with the cell line or BP cells survived beyond 12 weeks. The rate of increase in human cell numbers was higher for BP (7.3%/week) as compared with CP (0.9%/week) and AP (0. 5%/week). FISH analysis with BCR and ABL probes showed that some of the human cells engrafting after injection of CP cells lacked a BCR-ABL gene and were presumably normal. We conclude that CML cells proliferate in NOD/SCID mice with kinetics that recapitulate the phase of the donor's disease, thus providing an in vivo model of CML biology.
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PMID:The kinetics and extent of engraftment of chronic myelogenous leukemia cells in non-obese diabetic/severe combined immunodeficiency mice reflect the phase of the donor's disease: an in vivo model of chronic myelogenous leukemia biology. 969 28

We report a patient with Philadelphia chromosome (Ph1)-positive chronic myelogenous leukemia (CML) which transformed into blast crisis bearing the immunophenotypic features similar to those of the myeloid/natural killer (NK) cell precursor leukemia we proposed previously. Using a CD45 blast gating method, the myeloperoxidase-negative blasts were positive for CD7, CD13, CD33, CD34, CD56, and HLA-DR, but no other lymphoid antigens. Southern blot analysis showed germ line T cell receptor beta and delta genes and immunoglobulin heavy and light chain genes. Although NK cell blastic transformation with Ph1 positive CML has been reported in a single patient, this is, to our knowledge, the first report of CML blast crisis of myeloid/NK cell precursor origin.
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PMID:Blast crisis of chronic myelogenous leukemia exhibiting immunophenotypic features of a myeloid/natural killer cell precursor. 1007 56

In order to determine the relationship between bone marrow (bm) endosteal cells (EDC) and hemopoietic progenitors, we have analyzed the immunophenotype of EDC using various antibodies (Ab) against mesenchymal antigens. The Ab were applied on paraffin sections of normal bm (iliac crest, n=17; talus, n=1; phalanx, n=1), myeloregenerative bm (after chemotherapy), and hematologic disorders (acute myeloid leukemia (AML), n=8; chronic myeloid leukemia (CML), n=6; myelodysplastic syndromes (MDS), n=14; severe aplastic anemia (SAA), n=4; essential thrombocythemia (ET), n=2; idiopathic (primary) osteomyelo-fibrosis (IMF), n=1; polycythemia vera (PV), n=1). In normal bm, EDC were found to react with Ab against vimentin, tenascin, alpha-smooth muscle actin, osteocalcin, CD51, and CD56, but did not react with Ab against CD3, CD15, CD20, CD34, CD45, CD68, or CD117. An identical phenotype of EDC was found in AML, MDS, SAA, ET, IMF, PV, myeloregenerative bm, and peripheral bones lacking active hemopoiesis (talus, phalanx). In patients with CML, EDC reacted with Ab to CD51, but did not react with Ab to CD56. Based on their unique antigen profile, EDC were enriched from normal bm by enzyme digestion and cell sorting. However, these enriched cells (CD56+, CD45-, CD34-) did not give rise to hemopoietic cells under the culture conditions used, i.e. in the presence of the growth factors IGF-1, bFGF, SCF, IL-3, and GM-CSF Together, our data do not support the hypothesis that EDC are totipotent mesenchymal progenitors giving rise to hemopoietic cells.
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PMID:Immunophenotypic characterization of human bone marrow endosteal cells. 1039 6

We report on two patients with chronic myeloid leukemia (CML) who presented blastic transformation involving the skin, with leukemic infiltrates showing unusual morphologic and immunohistologic characteristics. Both patients were elderly men with a 36-month and a 40-month history of CML, respectively. They presented with disseminated, reddish to violaceous papules and plaques (case 1), and with localized reddish nodules on the left temporal area (case 2). Concurrent features of blastic transformation in the bone marrow were observed in one patient (case 1). Histopathologic examination of skin lesions revealed similar features in both cases. There was a moderate to dense dermal infiltrate composed mainly of medium-sized atypical mononuclear myeloid precursor cells with only few relatively well-differentiated cells of the granulocytic series. Histochemical staining for naphthol-ASD-chloroacetate esterase revealed strong positivity (>50% of neoplastic cells) in case 2 and only scattered positivity (< 10% of neoplastic cells) in case 1. Immunohistologic analysis performed on paraffin-embedded sections showed in both cases variable reactivity of neoplastic cells for leucocyte common antigen (CD45), lysozyme, myeloperoxidase, CD11c, CD15, CD43, CD66, CD68, HLA-DR, and the neural cell adhesion molecule (NCAM) CD56. A negative reaction was observed for CD3, CD34, and TdT. The immunohistologic findings were remarkably similar to those reported for acute myeloid leukemia (AML) with monocytic differentiation (French-American-British [FAB] classification, subtype M4). Examination of blasts from the bone marrow performed in one patient (case 1) revealed a similar phenotype also with CD56 expression. In conclusion, our observations show that specific cutaneous infiltrates in CML may show morphologic and immunohistochemical characteristics similar to those observed in AML with monocytic differentiation. Moreover, specific cutaneous manifestations of CML may express CD56.
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PMID:CD56+ blastic transformation of chronic myeloid leukemia involving the skin. 1059 40

In vivo megakaryocytopoiesis was directly analyzed for megakaryocyte (MK) number and mass, expression of lineage-specific and myeloid differentiation markers, and cell maturation as determined by size, granularity and ploidy. Using a rapid method for multiparameter correlative analysis with three-color flow cytometry (FCM) and a single-argon-ion-laser analyzer, cell DNA in aspirated marrow was stained with 7-amino-actinomycin D, and surface membrane receptors were analyzed with antibodies and cytokines labeled with fluorescein, phycoerythrin and peridinin chlorophyll protein. MKs expressing glycoprotein (GP) IIb/IIIa were enumerated in relation to the nucleated erythroid precursors expressing glycophorin A, and MK diameters were measured by time-of-flight technique. In human marrow (n = 10) the average MK diameter is 37 microm (range: 21 microm for 2N to 56 microm for 64N cells), volume is 26 x 10(3) fL, and MK number is 10 x 10(6)/kg, giving a total MK mass of 26 x 10(10) fL/kg. The modal ploidy is 16N. In essential thrombocythemia patients (n = 10) with a mean platelet count of 907 +/- 23 x 10(6)/L, MK number and volume increased twofold with modal ploidy of 32N, and MK mass fourfold the normal value. After reducing the platelet count to 353 +/- 42 x 10(6)/L with anagrelide therapy, MK number and volume decreased with modal ploidy of 16N, resulting in reduced MK mass by 50%. By contrast, patients with chronic myelogenous leukemia (n = 3) showed an increase in small MKs with a modal ploidy of 8N. In non-human primates, treatment with interleukin 6 or GM-CSF increased MK volume and ploidy with a variable increase in cell number and platelet counts. Treatment with recombinant human MK growth and development factor (n = 6, 5 microg/kg for 28 days) increased platelet count fivefold, MK number fourfold, MK volume twofold and total mass sevenfold. Using three-color FCM, marrow MKs labeled for GPIIb/IIIa and stained for DNA expressed high levels of von Willebrand factor with a high resolution of 2N/4N MKs from the total marrow cells. The expression of myeloid markers including CD36, CD45 and IgG-Fc gammaRII CDw32 correlated directly with increasing cell maturation, concordant with the expression of GPIIb/IIIa and GPIb. Conversely, the expression of HLA-DR declined with maturation. We conclude that pathophysiologic and therapeutic changes in megakaryocytopoiesis in vivo are readily quantified using FCM measurements.
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PMID:Measurements of in vivo megakaryocytopoiesis: studies in nonhuman primates and patients. 1101 99

Using red cell phenotyping (RCP) and/or cytogenetics (CYT) we identified 19 patients with persisting mixed chimerism (MC) among 231 patients transplanted with partially T cell-depleted stem cell grafts from HLA-identical siblings. Persisting MC is defined as MC for more than 2 years in patients without any evidence of relapse. Median leukemia-free survival in these patients was 150 (range, 50-218) months. Diagnoses were ALL (n= 10); AML (n = 2); CML (n = 2); NHL (n = 2); MDS (n= 1); MM (n = 1) and SAA (n = 1). Purpose of this study was the long-term follow-up of MC and definition of patterns of chimerism in the various subsets of PBMCs and granulocytes. Using a PCR-STR technique CD3(+)/CD4(+) (T4 lymphocytes), CD3(+)/CD8(+) (T8 lymphocytes), CD45(+)/CD19(+) (B lymphocytes), CD45(+)/CD14(+) (monocytes), CD45(+)/CD15(+) (granulocytes) and CD3(-)/CD56(+) (NK-cells) were analyzed. The majority of patients with persisting MC were conditioned with a less intensive conditioning regimen and had little GVHD. Sequential monitoring of the chimerism resulted in a group of patients (n = 7) with very slow transient mixed chimerism that resulted in complete DC after median 7 years. Another nine patients had a relatively high percentage of persisting autologous cells for a median of 12 years and in three patients we observed a stable low percentage of autologous cells. Only two out of 19 patients (AML-CR1, CML-CP1) relapsed during follow-up. Both patients had a relatively high percentage of autologous cells. Chimerism in granulocytes and PBMC subsets was analyzed at a median of 8 years after SCT in nine patients. In five patients mixed chimerism simultaneously detected by RCP and CYT was associated with MC in all subsets. Within each individual patient the percentages of donor and recipient cells were very different between the different subsets. Two CML-CP1 patients were mixed chimera in only two subsets and in one patient these subsets represented pending relapse. In another two patients mixed chimerism with a very low number of autologous red cells was not found in the PBMCs because of the different sensitivity level of the RCP and the PCR-STR technique. We conclude that in patients with persisting mixed chimerism after partially T cell-depleted SCT a remarkable number of patients had lymphoid malignancies, the majority of the patients were conditioned with less intensive conditioning regimens and the mixed chimerism was not correlated with relapse. Chimerism in granulocytes and PBMC subsets did show great intra-individual differences in the subsets and these data correlated well with RCP and CYT data with the exception of the NK cells.
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PMID:Long-term follow-up of persisting mixed chimerism after partially T cell-depleted allogeneic stem cell transplantation. 1184 Feb 58

Conventional cytotoxic therapy of hematologic malignancies is often associated with significant morbidity. This morbidity is often due to the lack of specificity for hematopoietic cells. Therefore, the concept of targeted therapy for patients with hematologic malignancies has received attention for many years. The goal of monoclonal antibody therapy is to target specific cell surface antigens on malignant hematopoietic cells, while sparing normal cells and tissues. Currently, monoclonal antibodies are being evaluated for their cytotoxic effects as well as their ability to deliver toxic agents or radiation. Rituximab, a chimeric anti-CD20 antibody, has shown response rates of approximately 50% with minimal toxicity in patients with refractory indolent lymphoma. Campath-1H (anti-CD52) has shown encouraging results in patients previously treated for chronic lymphocytic leukemia, with response rates up to 33%, although with significant toxicity. Anti-CD33 antibodies are being used to deliver cytotoxic agents, such as calicheamicin to patients with acute myeloid leukemia with response rates up to 30%. In addition, anti-CD33 and anti-CD45 antibodies have been used to deliver radiation directly to leukemic cells. (131)I-labeled anti-CD45 antibodies are being studied in combination with conventional preparative regimens in patients receiving bone marrow transplantation. Lastly, the therapeutic agent STI571 (signal transduction inhibitor 571) has demonstrated the capability of targeting specific molecular abnormalities seen in hematologic malignancies. STI571 targets the tyrosine kinase activity of the bcr-abl fusion protein seen in chronic myeloid leukemia. STI571 has induced complete hematologic responses in up to 98% of patients evaluated in clinical trials.
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PMID:Cell surface antigen and molecular targeting in the treatment of hematologic malignancies. 1200 80

The leukemogenic property of BCR-ABL in chronic myeloid leukemia (CML) is critically dependent on its protein tyrosine kinase activity. STI571 inhibits the BCR-ABL kinase activity, the growth and the viability of BCR-ABL expressing cells. In this study, we report the apoptotic effect of STI571 in combination with daunorubicin (DNR) on peripheral blood mononuclear cells from 11 CML patients and four BCR-ABL-positive cell lines: AR230, LAMA84, K562 and KCL22. Primary blast cells were identified by flow cytometry on the basis of their low CD45 expression. Nucleus fragmentation, exposure of phosphatidylserines and decrease in mitochondrial membrane potential were measured using acridine orange, FITC-annexin V and DiOC6(3), respectively, to evaluate apoptosis. On cell lines, the effect of DNR was negligible, whereas STI571 induced 10 to 35% of apoptosis in 18 h. STI571 sensitized AR230, LAMA84 and K562 cells to DNR when apoptosis was measured at the mitochondrial and membrane but not the nuclear levels. On CML blast cells, phosphatidyl serine exposure was significantly induced by both DNR and STI571 and was higher when these drugs were used in combination (P < 0.0003). However, the effects of this drug combination were only additive and no sensitization of blast cells to DNR by STI571 was observed. Interestingly, sensitization was evidenced in CML but not normal lymphocytes. These results suggest that other mechanisms additional to Bcr-Abl tyrosine kinase activity could be responsible for DNR resistance, and further investigations are needed to understand its origin.
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PMID:Resistance to daunorubicin-induced apoptosis is not completely reversed in CML blast cells by STI571. 1204 Apr 47

Recent advances have made haploidentical transplantation for leukemia feasible, but the rigorous T-cell depletion used contributes to the high relapse rates observed. We have attempted to improve the graft-versus-leukemia (GVL) effect by generating allorestricted cytotoxic T lymphocytes (CTLs) directed against human CD45. Such CTLs should recognize patient hematopoietic cells including leukemia, enhancing donor cell engraftment and improving the GVL effect, but they should not recognize host nonhematopoietic tissues or donor cells from the graft. Using the T2 binding assay, 4 CD45-derived peptides were found to bind HLA-A2 molecules. These peptides were used to generate cytotoxic T-cell lines from HLA-A2(-) donors by sequential stimulation with peptide-pulsed HLA-A2(+) stimulators, and the lines obtained were screened for peptide-specific cytotoxicity. Using one of these peptides (P1218), it was possible to generate peptide-specific, allorestricted CTLs in 3 of 7 responders. P1218-specific CTL lines show potent cytotoxicity against hematopoietic cell lines coexpressing HLA-A2 and CD45 but not CD45 loss variants. Studies with stable transfectants of 293 cells demonstrated recognition by P1218-specific CTLs of endogenously expressed CD45. Likewise P1218-specific CTLs recognized peripheral blood mononuclear cells (PBMCs) from HLA-A2(+) patients with chronic myeloid leukemia (CML) and leukemic blasts in HLA-A2(+) patients with acute myeloid leukemia (AML), but they were unable to lyse HLA-A2(+) fibroblasts or HLA-A2(-) normal PBMCs. Coculture of CD34(+) PBMCs and bone marrow mononuclear cells (BMMCs) with P1218-specific CTL significantly inhibited colony-forming unit-granulocyte macrophage (CFU-GM) formation in HLA-A2(+) healthy controls and CML patients but resulted in no significant inhibition in HLA-A2(-) healthy controls. These studies demonstrate that P1218-specific cytotoxic T lymphocytes (CTLs) have potent activity against leukemic progenitors and suggest that adoptive immunotherapy with allorestricted CTLs directed against CD45 epitopes may be useful in restoring the GVL effect after HLA-A2-mismatched haploidentical transplantation. Further, because P1218-specific CTLs also recognize healthy HLA-A2(+) progenitors, such CTLs could also contribute to host myeloablation and enhance donor cell engraftment.
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PMID:Allorestricted cytotoxic T cells specific for human CD45 show potent antileukemic activity. 1239 6

Radioimmunotherapy (RIT) with radiolabelled monoclonal antibodies (mAbs) is an effective method of achieving myeloablation in leukaemia patients prior to stem cell transplantation (SCT). We wished to compare the approaches of specific binding to leukaemic blasts and non-specific binding to benign red marrow cells, which results in a myeloablative "cross-fire" effect. Therefore, we prospectively evaluated the biodistribution and biokinetics of the anti-CD45 mAb YTH 24.5 and the anti-CD66 mAb BW 250/183 with regard to their suitability for myeloablative RIT. The red marrow selective anti-CD66 mAb BW 250/183 (IgG1) binds to normal granulopoietic cells. In contrast, the anti-CD45 mAb YTH 24.5 (IgG2b) binds to 85-90% of acute leukaemic blasts and almost all haematopoietic white cells. Patients with leukaemic blast infiltration of the marrow <25% and assigned for RIT and SCT were included. Twelve patients (eight male, four female; median age 46+/-7 years) with AML (5), CML (5) or ALL (2) were examined. Both mAbs were labelled with technetium-99m. Within 48 h, 906+/-209 MBq (99m)Tc-anti-CD66 mAb and 760+/-331 MBq (99m)Tc-anti-CD45 mAb were injected consecutively. Scintigraphic and urinary measurements were performed 1, 2, 4 and 24 h after injection. Serum activities were evaluated 2, 5, 10, 15, 30 and 60 min and 2, 4 and 24 h after injection. Compared with the anti-CD45 mAb, the anti-CD66 mAb showed an approximately fourfold higher accumulation in the red marrow, a 2.5-fold lower accumulation in the liver and similar accumulation in the kidneys. The serum activity (% of the injected dose) initially decreased faster for the anti-CD45 mAb but was similar for the two mAbs 24 h after injection: 3.3%+/-1.2% (anti-CD66 mAb) and 2.4%+/-1.1% (anti-CD45 mAb). The cumulated urinary excretion was 17%+/-6.6% (anti-CD66 mAb) and 27.3%+/-7.9% (anti-CD45 mAb) 24 h after application. In these patients with low tumour load, the anti-CD66 mAb BW 250/183 showed more favourable properties in terms of biodistribution and pharmacokinetics. Thus, it appears superior to anti-CD45 mAb YTH 24.5 in selectively increasing the marrow dose and avoiding extramedullary organ toxicity.
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PMID:A comparison of the biodistribution and biokinetics of (99m)Tc-anti-CD66 mAb BW 250/183 and (99m)Tc-anti-CD45 mAb YTH 24.5 with regard to suitability for myeloablative radioimmunotherapy. 1259 12


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