Altered growth characteristics of cord blood cells after in vivo exposure to maternal acute myeloid leukemia and chemotherapy.
Explore the source record for details and available documents.
Adult↗
SEARCH · PubMed Health
Results for “Granulocyte Precursor Cells”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Direct transformation of fixed mesenchymal cells into myelocytes in the guinea pig bone marrow.
Explore the source record for details and available documents.
Bone Marrow↗
Histone H3 tail positioning and acetylation by the c-Myb but not the v-Myb DNA-binding SANT domain.
The c-Myb transcription factor coordinates proliferation and differentiation of hematopoietic precursor cells. Myb has three consecutive N-terminal SANT-type repeat domains (R1, R2, R3), two of which (R2, R3) form the DNA-binding domain (DBD). Three amino acid substitutions in R2 alter the way Myb regulates genes and determine the leukemogenicity of the retrovirally transduced v-Myb oncogene. The molecular mechanism of how these mutations unleash the leukemogenic potential of Myb is unknown. Here we demonstrate that the c-Myb-DBD binds to the N-terminal histone tails of H3 and H3.3. C-Myb binding facilitates histone tail acetylation, which is mandatory during activation of prevalent differentiation genes in conjunction with CCAAT enhancer-binding proteins (C/EBP). Leukemogenic mutations in v-Myb eliminate the interaction with H3 and acetylation of H3 tails and abolish activation of endogenous differentiation genes. In primary v-myb-transformed myeloblasts, pharmacologic enhancement of H3 acetylation restored activation of differentiation genes and induced cell differentiation. Our data link a novel chromatin function of c-Myb with lineage-specific expression of differentiation genes and relate the loss of this function with the leukemic conversion of Myb.
Acetylation↗
Autologous rescue with blood-derived stem cells in a child with non-Hodgkin's lymphoma.
Autologous blood-derived stem cells were used for stem-cell rescue in a 5-year-old boy with chemotherapy-resistant B-Non-Hodgkin's lymphoma (B-NHL) involving bone marrow. The high dose chemoradiotherapy was carried out 5 months after initial diagnosis during partial remission. The preparative regimen consisted of 12 Gy fractionated, total-body irradiation (FTBI) before 60 mg/kg etoposide. There were 22.96 X 10(4)/kg body weight myeloid precursor cells, granulocyte-macrophage committed stem cells (CFU-GM) collected by intermittent blood flow separation with a Haemonetics 30R in two cytaphereses and stored in liquid nitrogen. Also 11, 82 X 10(4) CFU-GM/kg body weight were recovered and transfused after thawing. Rapid hematopoietic reconstitution ensued: Erythroid precursors were detected on day 9, 1 X 10(9)/L leucocytes were counted on day 11, and 0.5 X 10(9)/L granulocytes on day 13, respectively. The patient required 3 single-donor platelet transfusions, the last one on day 10. On day 17, 100 X 10(9)/L platelets were reached. A bone marrow aspirate on the same day showed good trilineage regeneration. The patient remained in complete remission 7 months after autografting with a normal stem cell content of the bone marrow and in the peripheral blood. On day 226, after stem cell infusion, a bone marrow relapse occurred.
Antineoplastic Combined Chemotherapy Protocols↗
Diamine oxidase is important in assessment of polyamine effects on hemopoietic cell proliferation in vitro.
A difference was observed in the effect of difluoromethlyornithine (DFMO), a specific inhibitor of ornithine decarboxylase, on human and murine granulocyte-macrophage precursor cell (CFU-C) proliferation in vitro, in the presence of fetal bovine serum (FBS) and horse serum (HS). A dose of DFMO which almost totally abolished CFU-C colonies in cultures containing FBS had no effect or very little effect on CFU-C in cultures supplemented with HS. This effect could be reversed by aminoguanidine reacting with diamine oxidase (DAO), which is present in FBS but not in HS. The importance of DAO in the assessment of polyamine effects is also suggested by decreased colony formation in cultures containing HS and DFMO only after the addition of this enzyme. Additionally, Mo T cell line cultures containing DFMO demonstrated a substantially lower intracellular concentration of putrescine in the presence of FBS rather than HS.
Amine Oxidase (Copper-Containing)↗
In vivo production of cytokines by bone marrow stromal cells and macrophages from patients with myelodysplastic syndrome.
We studied functional disturbances in hemopoietic microenvironment and cytokine production by stromal sublayer in long-term bone marrow cultures and peripheral blood macrophages from patients with various forms of myelodysplastic syndrome. Production of factors stimulating the growth of normal erythroid and granulocytic precursors by cells of the stromal sublayer from patients with refractory sideroblast anemia and refractory anemia with excess blasts is impaired compared to cells from healthy donors. The medium conditioned by macrophages from patients with chronic myelomonocytic leukemia displayed a higher ability to stimulate the growth of granulocytes and macrophages compared to media conditioned by cells from donors and patients with refractory sideroblast anemia and refractory anemia with excess blasts. Cultured stromal cells and macrophages produced tumor necrosis factor-alpha and interleukin-6. Their content in media conditioned by cells from patients with myelodysplastic syndrome surpassed that in healthy donors. Our results suggest that production of cytokines by stromal microenvironmental cells is impaired in patients with various forms of myelodysplastic syndrome.
Bone Marrow Cells↗
Electron microscopic identification of parvovirus virions in erythroid and granulocytic-line cells in a patient with human parvovirus B19 induced pancytopenia.
In this short report we describe a patient with human parvovirus B19 (HPV B19)-induced transient pancytopenia. Parvovirus virions were seen by electron microscopy in both erythroid and granulocytic precursors. Erythroid cells are not the only targets in these cases. We draw attention to this disorder so that physicians involved with hematological disorders and transplantation be more aware of this infection.
Adult↗
Large-scale expansion and transplantation of CD34(+) hematopoietic cells: in vitro and in vivo confirmation of neutropenia abrogation related to the expansion process without impairment of the long-term engraftment capacity.
BACKGROUND: Herein are reported the results obtained in all multiple myeloma patients transplanted with peripheral blood hematopoietic progenitor cells submitted to ex vivo expansion. STUDY DESIGN AND METHODS: Patients had blood progenitor cell mobilization with cyclophosphamide and filgrastim. CD34+ cells were expanded for 10 days in a medium containing granulocyte-colony-stimulating factor (G-CSF), stem cell factor, and megakaryocyte growth and development factor (MGDF). Twenty-seven patients underwent transplantation with expanded and nonexpanded cells and 7 patients underwent transplantation with expanded cells only. RESULTS: The median fold cell expansion was 29.1. The number of colony-forming unit-granulocyte-macrophage (CFU-GM) and CD34+ cells, and the long-term culture-initiating cell (LTC-IC) activity increased with median fold values of 14.7, 2.75, and 2.25, respectively. Postmyeloablative neutropenia was abrogated in 24 of 27 patients transplanted with expanded cells plus nonexpanded cells. The median duration of severe neutropenia was 0 days and correlated with the number of cells and CFU-GM infused. Survival was similar to that of a historical control group. Our LTC-IC and NOD-SCID mice studies showed that the expanded cells are able of sustaining long-term hematopoiesis. Seven other patients received transplantation with expanded cells alone. Absolute neutropenia was abrogated in 6 patients. The median duration of neutropenia was 0 days. Two patients who received the lower number of total cells or CFU-GM had brief secondary neutropenia, which resolved after G-CSF injections. CONCLUSION: CD34+ cells expanded ex vivo can abrogate absolute and severe neutropenia after high-dose therapy. The results of the amplification process are strongly related to the delay of hematopoietic recovery.
Adult↗
Developmental activation of the lysozyme gene in chicken macrophage cells is linked to core histone acetylation at its enhancer elements.
Native chromatin IP assays were used to define changes in core histone acetylation at the lysozyme locus during developmental maturation of chicken macrophages and stimulation to high-level expression by lipo-polysaccharide. In pluripotent precursors the lysozyme gene (Lys) is inactive and there is no acetylation of core histones at the gene, its promoter or at the upstream cis-control elements. In myeloblasts, where there is a very low level of Lys expression, H4 acetylation appears at the cis-control elements but not at the Lys gene or its promoter: neither H3 nor H2B become significantly acetylated in myeloblasts. In mature macrophages, Lys expression increases 5-fold: H4, H2B and H2A.Z are all acetylated at the cis-control elements but H3 remains unacetylated except at the -2.4 S silencer. Stimulation with LPS increases Lys expression a further 10-fold: this is accompanied by a rise in H3 acetylation throughout the cis-control elements; H4 and H2B acetylation remain substantial but acetylation at the Lys gene and its promoter remains low. Acetylation is thus concentrated at the cis-control elements, not at the Lys gene or its immediate promoter. H4 acetylation precedes H3 acetylation during development and H3 acetylation is most directly linked to high-level Lys expression.
Acetylation↗
Abnormalities in long-term bone culture from mice deficient in tumor necrosis factor: induction of apoptosis and cell proliferation.
The total duration of hemopoiesis and the total cell production in long-term bone marrow cultures from mice deficient by tumor necrosis factor are increased, while proliferation of granulocyte-macrophage precursor cells, the main cell populations in long-term bone marrow cultures, did not differ from that in wild-type mice. In bone marrow cultures from knockout mice the intensity of apoptosis remained low during 40-week culturing and was similar to that in early wild-type cultures (10 weeks). Then, the intensity of apoptosis in bone marrow cultures from knockout mice did not differ or even surpassed that in wild-type cultures. However, we observed no inhibition of hemopoiesis in bone marrow cultures from knockout mice. The absence of autocrine expression of tumor necrosis factor did not affect proliferation of precursor cells, but modulate the intensity of apoptosis. It remains unclear whether changes in apoptosis are related to intensive cell production.
Animals↗
Granulocyte colony-stimulating factor inhibits spontaneous cytochrome c release and mitochondria-dependent apoptosis of myelodysplastic syndrome hematopoietic progenitors.
Low-risk myelodysplastic syndromes (MDS), including refractory anemia and sideroblastic anemia, are characterized by increased apoptotic death of erythroid progenitors. The signaling pathways that elicit this pathologic cell death in MDS have, however, remained unclear. Treatment with erythropoietin in combination with granulocyte colony-stimulating factor (G-CSF) may synergistically improve the anemia in patients with MDS, with a concomitant decrease in the number of apoptotic bone marrow precursors. Moreover, we have previously reported that G-CSF inhibits Fas-induced caspase activation in sideroblastic anemia (RARS). The present data demonstrate that almost 50% of erythroid progenitor cells derived from patients with MDS exhibit spontaneous release of cytochrome c from mitochondria with ensuing activation of caspase-9, whereas normal erythroid progenitors display neither of these features. G-CSF significantly inhibited cytochrome c release and suppressed apoptosis, most noticeably in cells from patients with sideroblastic anemia. Furthermore, inhibition of caspase-9 suppressed both spontaneous and Fas-mediated apoptosis of erythroid progenitors in all low-risk MDS cases studied. We propose that the increased sensitivity of MDS progenitor cells to death receptor stimulation is due to a constitutive activation of the mitochondrial axis of the apoptotic signaling pathway in these cells. These studies yield a mechanistic explanation for the beneficial clinical effects of growth factor administration in patients with MDS, and provide a model for the study of growth factor-mediated suppression of apoptosis in other bone marrow disorders.
Adult↗
Identification of a hypoxic population of bone marrow cells.
A technique using collagenase has been devised to release and separate, with reproducibility, hematopoietic cells (HC) from various microenvironments of mouse femurs. HC were assayed by an in vitro gel culture technique used traditionally to score granulocyte-macrophage precursor cells (CFU-C). CFU-C which resided in the medullary cavity and endosteal regions were sensitive to ionizing radiation and resistant to misonidazole (MISO) cytotoxicity. CFU-C which resided within the compact bone were resistant to ionizing radiation and sensitive to the cytotoxic action of MISO. These results suggest that HC which reside in the bone are hypoxic and retain clonogenic potential. When animals were exposed to various treatments with MISO followed by myelotoxic doses of cyclophosphamide (CTX) or total body irradiation (TBI), the LD50 of both agents was significantly reduced. This result suggests that a hypoxic component of HC could be important in the regenerative process within the marrow after such myelotoxic trauma.
Animals↗
MOZ-TIF2, but not BCR-ABL, confers properties of leukemic stem cells to committed murine hematopoietic progenitors.
To better understand the origin of leukemic stem cells, we tested the hypothesis that all leukemia oncogenes could transform committed myeloid progenitor cells lacking the capacity for self-renewal, as has recently been reported for MLL-ENL. Flow-sorted populations of common myeloid progenitors and granulocyte-monocyte progenitors were transduced with the oncogenes MOZ-TIF2 and BCR-ABL, respectively. MOZ-TIF2-transduced progenitors could be serially replated in methylcellulose cultures and continuously propagated in liquid culture, and resulted in an acute myeloid leukemia in vivo that could be serially transplanted. In contrast, BCR-ABL transduction conferred none of these properties to hematopoietic progenitors. These data demonstrate that some, but not all, leukemia oncogenes can confer properties of leukemic stem cells to hematopoietic progenitors destined to undergo apoptotic cell death.
Acute Disease↗
Stable multilineage chimerism without graft versus host disease following nonmyeloablative haploidentical hematopoietic cell transplantation.
BACKGROUND: Hematopoietic cell transplantation may offer the only cure for patients with hematological diseases. The clinical application of this therapy has been limited by toxic conditioning and lack of matched donors. Haploidentical transplantation would serve to extend the potential donor pool; however, transplantation across major histocompatibility complex barriers is often associated with severe graft-versus-host disease. Here we evaluate a novel protocol to achieve engraftment across mismatch barriers without toxic conditioning or significant posttransplant complications. METHODS: Nine major histocompatibility complex (MHC)-defined miniature swine received haploidentical hematopoietic cell transplantation following standard myeloablative conditioning. Nine additional animals received haploidentical hematopoietic cell transplantation following a minimally myelosuppressive regimen, consisting of 100 cGy total body irradiation, immunotoxin mediated T-cell depletion, and a short course of cyclosporine. Donor cell engraftment and peripheral chimerism was assessed by polymerase chain reaction and flow cytometry. Graft-versus-host disease was monitored by clinical grading and histology of skin biopsy specimens. RESULTS: All animals conditioned for haploidentical hematopoietic cell transplantation using myeloablative conditioning were euthanized within 2 weeks due to engraftment failure or graft-versus-host disease. All animals conditioned with the nonmyeloablative regimen developed multilineage peripheral blood chimerism during the first 2 months following transplantation. Six animals evaluated beyond 100 days maintained multilineage chimerism in the peripheral blood and lymphoid tissues, showed evidence of progenitor cell engraftment in the bone marrow, and had minimal treatment-related complications. CONCLUSIONS: Here we report that stable multilineage chimerism and engraftment can be established across haploidentical major histocompatibility complex barriers with minimal treatment-related toxicity and without significant risk of graft-versus-host disease.
Animals↗
Cytotoxicity of materials used in perforation repair tested using the V79 fibroblast cell line and the granulocyte-macrophage progenitor cells.
AIM: To compare the cytotoxicity of materials used to repair perforations using permanent V79 fibroblasts and murine granulocyte-macrophage progenitor cells (CFU-GM). METHODOLOGY: Set specimens from amalgam, glass-ionomer, SuperEBA, N-Rickert, MTA and gutta-percha were eluted with culture medium for 72 h and their cytotoxicities were assessed by incubating the extracts with V79 and bone marrow-derived progenitors for 24 h and 7 days, respectively. Cytotoxicity on V79 cells was judged using the total nucleic acid content (NAC), neutral red uptake (NRU) and reduction of the tetrazolium salt (MTT). The number of bone marrow CFU-GM colonies determined in clonal cultures stimulated with recombinant murine granulocyte-macrophage colony-stimulating factor was used to assess cytotoxicity to progenitor cells. Statistical analyses were conducted using the one-way analysis of variance and Tukey's test where appropriate. RESULTS: All materials were cytotoxic in both cell systems; however, CFU-GM was more sensitive to the extracts than V79 cells. A similar rank order of toxicity was observed in V79 cells using the NAC and the MTT assays: glass-ionomer > N-Rickert congruent with SuperEBA > gutta-percha > amalgam congruent with MTA (P < 0.05). In contrast, the NRU test exhibited a lower sensitivity to MTA, gutta-percha and amalgam extracts. In the clonal culture assay, the toxicity was less pronounced in the presence of gutta-percha, SuperEBA and MTA. Similar cellular responses were found by placing the set specimens directly in the clonal culture dishes. CONCLUSIONS: The sensitivity of toxicity depended on the choice of the endpoint and the cell-culture system. Nevertheless, MTA was ranked as the least cytotoxic cement in both cell systems.
Acrylic Resins↗
[Cultivation of human peripheral blood leukocytes on agar gel].
It was shown by the modified method of agar cultures that in the peripheral blood of a healthy man, aged from 4 days to 40 years. The number of cell precursors of granulocytes and macrophages (CFU-C) varied from 0.05 to 6.38 in adults and from 0.2 to 2.9 in children per 105 nuclear cells. CFU-C content in the patients with infectious mononucleosis and acute leukemia was 0.5--14 and 0--0.3 per 105 nuclear cells, respectively.
Acute Disease↗
Accelerated recovery of 5-fluorouracil-damaged bone marrow after rosiglitazone treatment.
Our preliminary data indicate that rosiglitazone may be myeloprotective. We investigated whether it can modify bone marrow recovery. Five-day pre-treatment with rosiglitazone significantly accelerated recovery of 5-fluorouracil-damaged bone marrow in mice. Frequency and femoral content of granulocyte-macrophage progenitors reached mean baseline faster in pre-treated groups than in 5-fluorouracil-treated controls. Consequently, neutropenia was milder. Five-day insulin pre-treatment had similar effects in vivo. Insulin supports in vitro hematopoiesis. The observed myeloprotection demonstrated the importance of insulin in vivo. Clinical use of insulin to moderate myelotoxicity is impractical but rosiglitazone, an insulin sensitizer, could offer hope. Although rosiglitazone tends to increase plasma insulin levels, the significant myeloprotection was partly due to direct effects on progenitors. In vitro rosiglitazone enhanced the survival of both murine progenitor and human mobilized blood stem cells in the presence of 5-fluorouracil, the effect of which was neutralized by a peroxisome-proliferator-activated receptor-gamma antagonist.
Administration, Oral↗
Tetraploid myeloid cells in donors of peripheral blood stem cells treated with rhG-CSF.
Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is frequently used to mobilize CD34+ cells in healthy donors and patient with malignant diseases prior to peripheral blood stem cell (PBSC) harvest. To analyze the effects of rhG-CSF on morphology and genotype of white blood cells, a novel multiparametric cell scanning system that combines morphologic, immune and genotypic analyses of the same cells was used. We report here that tetraploid myeloid cells are present in the peripheral blood of donors treated with rhG-CSF. The tetraploidy was detected in up to 0.6% of differentiated myeloid cells and all observed CD34+ cells were diploid. Thus, short treatment with rhG-CSF of PBSC donors induces numerfical chromosomal alterations in a small subset of mature myeloid cells.
Case-Control Studies↗