Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the effects of granulocyte-macrophage colony-stimulating factor, interleukin-3, stem cell factor, interleukin-6, and granulocyte colony-stimulating factor (G-CSF) alone, and in combination, on the clonogenic potential of normal and aplastic anemia (AA) bone marrow mononuclear cells (BMMC and CD34+ cells. AA BMMC consistently produced a significantly lower absolute number of colonies than normal, but, when account was taken of the reduced proportion of CD34+ cells in AA BM, there was no significant difference in terms of cloning efficiency (CE). However, when removed from the influence of accessory cells, the CE of AA CD34+ cells decreased significantly more than normal, indicating a defect in their function, either in terms of dependence on accessory cell-derived factors or susceptibility to cell damage when sorted. Of the factors studied, G-CSF had the most significant effect on the response of CD34+ cells from both groups when removed from their accessory cells. This was particularly true for AA CD34+ cells, whose response to cytokine stimuli containing G-CSF enabled them to match the response of normal CD34+ cells.
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PMID:Aplastic anemia: evidence for dysfunctional bone marrow progenitor cells and the corrective effect of granulocyte colony-stimulating factor in vitro. 860 32

To date, six hematopoietic growth factors, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), interleukin-1 (IL-1), interleukin-6 (IL-6) and erythropoietin (Epo), have been used in the treatment of patients with aplastic anemia (AA). Among them, G-CSF and GM-CSF are effective in correcting neutropenia in some patients with AA, but in general, patients with very severe hypoplasia do not respond to conventional doses of either agent. These factors have been used in the treatment of AA as follows: (1) as adjuvant therapy for severe infections; (2) as adjuvant therapy to immunosuppressive therapy (IS); and (3) as second-line therapy for patients refractory to IS. The results of clinical trials with antilymphocyte globulin, cyclosporine combined with G-CSF have been remarkable both in Europe and in Japan. Ongoing randomized studies with long-term follow-up will reveal the effects of hematopoietic growth factors on both hematopoiesis and the long-term course of the disease, including the later development of clonal disorders.
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PMID:Use of hematopoietic growth factors for treatment of aplastic anemia. 897 6

Serious hematologic complications associated with ticlopidine have been reported, including aplastic anemia. We report here an additional case of fatal aplastic anemia due to ticlopidine. A 66-year-old male patient developed fever and pancytopenia 2 months after ticlopidine was started. Despite the administration of granulocyte colony-stimulating factor (G-CSF) and broad-spectrum antibiotics, as well as aggressive red cell and platelet transfusions, the patient died 16 days after admission due to septic shock. Eighteen other cases of ticlopidine-induced aplastic anemia published in the English literature are also reviewed and presented here. Eight of the total 19 patients (including the one reported here) have died, mostly due to infection. Of the seven who received supportive treatment only, four had spontaneous recovery. Nine cases were treated with G-CSF or granulocyte-macrophage colony-stimulating factor (GM-CSF), and response was observed in only four of them. Several other cases were treated with high-dose corticosteroids or androgens; however, it was not possible to evaluate the efficacy of these treatments because of the limited number of cases. In the absence of satisfactory treatment for ticlopidine-induced aplastic anemia at present, it may be reasonable to try antilymphocyte globulin or cyclosporine. Also, great efforts should be made in the prevention and management of infection accompanying this disease.
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PMID:Ticlopidine-associated aplastic anemia. A case report and review of literature. 954 Jul 64

An abnormal bone marrow microenvironment and hematopoietic growth factors are considered as one of the possible mechanisms of aplastic anemia. Circulating levels of erythropoietin, granulocyte colony-stimulating factor (G-GSF), granulocyte-macrophage colony-stimulating factor (GM-GSF) and thrombopoietin are significantly higher in patients with aplastic anemia than in normal controls. Of the two hematopoietic growth factors, acting at the early stages of hematopoiesis, circulating levels of flt-3 ligand are highly elevated in patients with aplastic anemia, whereas those of stem cell factor (SCF) are essentially normal. Decreased production has been described only for interleukin (IL) 1. This may reflect defective monocyte-macrophage maturation in patients with aplastic anemia. Marrow stromal cells are thought to exert a regulatory role in hematopoiesis, at least in part, by the production of certain hematopoietic growth factors. The abilities of stromal cells to produce hematopoietic growth factors, including G-GSF, GM-CSF, IL-6 and SCF, are either normal or elevated in the majority of patients. Thus, the deficiencies of hematopoietic growth factors are unlikely to be the cause of aplastic anemia.
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PMID:Hematopoietic growth factors and marrow stroma in aplastic anemia. 971 65

To evaluate the therapeutic potential of hematopoietic growth factors (HGFs) during immunosuppressive treatment (IST) of severe aplastic anemia (SAA), 38 patients with newly diagnosed SAA received IST alone (group I), or IST plus recombinant human erythropoietin and granulocyte-macrophage colony-stimulating factor (rhEPO + rhGM-CSF) (group II). Eleven patients in each group received antilymphocyte globulin (ALG) for IST, and eight patients in each group received cyclosporine (CSA). Complete remission rates at one year were 26% and 74% for group I and group II patients, respectively. The ALG-treated subgroup showed the greatest differences between treatments. Compared with patients receiving ALG alone, patients treated with ALG plus HGFs had significantly better one-year survival (100% vs. 54.5%, P < 0.05), complete remission rates (91% vs. 36%, P < 0.05), more rapid and complete hematologic recovery, greater reductions in transfusion requirements, and lower infection rates. The data suggest a potential role for rhEPO + rhGM-CSF therapy in SAA patients receiving IST.
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PMID:Treatment of severe aplastic anemia with an immunosuppressive agent plus recombinant human granulocyte-macrophage colony-stimulating factor and erythropoietin. 979 55

We have recently shown that in patients with aplastic anemia (AA) recovering following immunosuppressive therapy, the persistent reduction in the bone marrow clonogenic potential is unrelated to suppressive effects of the myeloid stroma and intrinsic to the hematopoietic progenitors. We examined the mechanisms of this defect by determining the response of the aplastic CD34+ clonogenic precursors to proliferative signals induced by hematopoietic growth factors and comparing their results with those of a control population. Light density bone marrow mononuclear cells were lymphocyte and monocyte depleted and enhanced for the CD34+ progenitors by immunomagnetic selection. Selected progenitors were then cultured in the mixed colony assay with incremental concentrations of combinations containing erythropoietin (Epo), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3) and c-kit ligand. Bone marrow from aplastic patients had significantly fewer light density cells displaying the CD34 antigen (mean 0.65%, SD 0.35 vs. 1.62%, SD 1.4; p=0.002). Dose response studies on aplastic CD34+ cells demonstrated that at low concentrations of Epo, IL-3 and GM-CSF, clonogenic growth was significantly impaired but achieved normal values at concentrations giving plateau growth in control cultures. However, for all colony types, responses to effective concentrations of c-kit ligand corresponded with those of controls. These data suggest abnormalities at the receptor or signal transduction levels.
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PMID:In aplastic anemia progenitor cells have a reduced sensitivity to the effects of growth factors. 1048 68

Interleukin (IL)-3 is a multipotent hematopoietic growth factor produced by activated T cells, monocytes/macrophages and stroma cells. The human IL-3 gene is located on chromosome 5 near segment 5q31. The high-affinity receptor for human IL-3 is composed of alpha and beta subunits. IL-3 shares a common beta subunit with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-5; this subunit has been mapped to chromosome 22q13.1. The biological effects of IL-3 have been studied in human and murine hematopoietic cell lines and normal human marrow cells. Addition of IL-3 to the culture medium induces proliferation, maturation and probably self-renewal of pluripotent hematopoietic stem cells and cells of myeloid, erythroid and megakaryocytic lineages. Human IL-3 was cloned in 1986, and since then various clinical trials have assessed the in vivo potential of recombinant human (rhIL-3). Initial results of phase I/II studies of IL-3 at a dose of 5-10 microg/kg subcutaneously daily for 5-10 days in patients with relapsed lymphomas, small-cell lung cancer, breast cancer and ovarian cancer showed that post-chemotherapy application of IL-3 reduces chemotherapy delays and induces faster regeneration of granulocytes and platelets. However, these results were not confirmed in phase III studies. The role of IL-3 alone in the treatment of myelodysplastic syndromes (MDS), aplastic anemia (AA) and other bone marrow failure disorders have also been disappointing. However, preliminary studies of IL-3 in combination with chemotherapeutic agents and immunosuppression have demonstrated encouraging results in patients with MDS and AA respectively. The therapeutic potential of IL-3 in peripheral blood stem cell (PBSC) harvesting and priming of stem cells before harvest is beginning to be identified. Initial results of IL-3 combination with GM-CSF or later-acting growth factors such as granulocyte colony-stimulating factor (G-CSF) have yielded larger amounts of PBSC during harvesting. In recent years, the availability of synthetic IL-3 receptor (IL-3R) agonists and similar chimeric molecules with greater in vitro biological activity and fewer inflammatory side-effects has extended our options to employ and compare these molecules and rhIL-3 for the prevention of chemotherapy-induced myelosuppression. The role of IL-3 and IL-3R agonists in ex vivo expansion of stem cells, dendritic cell development and gene transfer requires further evaluation. It appears that future application of IL-3 in combination with other cytokines is an attractive way forward in the prevention of treatment-related mortality and morbidity in oncology patients. It also shows prospects for the development of new therapeutic strategies for dose escalation and immune modulation for cancer patients with relapsed and resistant disease.
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PMID:Interleukin-3 in hematology and oncology: current state of knowledge and future directions. 1051 81

We have previously shown that the levels of hematopoietic progenitors in long-term marrow cultures (LTMC) from patients with aplastic anemia (AA) are drastically reduced, as compared to normal LTMC. We have also reported that when LTMC from AA patients are supplemented with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) there is an increase in colony-forming cell (CFC) levels. However, such a stimulation is only transient and it is followed by an inhibition in CFC growth. Based on these observations, in the present study we have tested the hypothesis that the levels of tumor necrosis factor-alpha (TNF-alpha), an inhibitor of hematopoiesis, are increased in AA LTMC and that such levels are further increased after rhGM-CSF has been added to the cultures for several weeks. Accordingly, we have determined the levels of TNF-alpha in the supernatant of LTMC established from normal (n = 8) and AA (n = 6) bone marrow and in AA LTMC supplemented with rhGM-CSF (n = 6). At the time of culture initiation, TNF-alpha levels were below detection in all the samples analyzed. After 5 weeks of culture, TNF-alpha levels in normal LTMC were very low, with a median of 7.3 pg/mL. In contrast, AA LTMC contained higher levels of TNF-alpha (median of 49.6 pg/mL). In keeping with our hypothesis, addition of rhGM-CSF to AA LTMC resulted in a significant further increase of TNF-alpha levels (median of 135.4 pg/mL). Our results demonstrate an inverse correlation between reduced hematopoiesis in AA LTMC and increased levels of TNF-alpha in this culture system. Based on the results presented here, together with previous reports indicating that TNF-alpha is a potent inducer of apoptosis in hematopoietic progenitor cells, it seems reasonable to suggest that TNF-alpha is implicated in the pathophysiology of AA.
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PMID:Tumor necrosis factor-alpha levels in long-term marrow cultures from patients with aplastic anemia: modulation by granulocyte-macrophage colony-stimulating factor. 1175 94

Previously, we and others have shown that fetal liver infusion (FLI) leads to autologous hematopoietic improvement in 40-54% of patients with aplastic anemia. However, whether this recovery was spontaneous or the effect of the infused liver cells was not clear. To dissect the role of FLI in autologous hematopoietic recovery, the colony-supporting potential of fetal liver-conditioned medium (FLCM) was evaluated in bone marrow (BM) cells of normal adult and aplastic anemia patients. In both cases, each sample of FLCM supported the growth of colony-forming cells in semi solid culture medium. The FLCM was assayed for the presence of four principal colony-stimulating cytokines, namely stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and erythropoietin (Epo). While GM-CSF, IL-3, and Epo were present in insignificant amounts or were altogether absent, 50-635 pg/ml of SCF was found in 8 of the 13 FLCM samples tested. Preliminary results of bioneutralization assay indicated the possible role of SCF, secreted by the FL cells, in colony-supporting activity of aplastic anemia and normal BM cells. Overall, our in vitro study implicates the paracrine role of infused FL cells in regenerating autologous hematopoiesis in aplastic anemia patients.
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PMID:Colony-stimulating activity of fetal liver cells: synergistic role of stem cell factor in bone marrow recovery from aplastic anemia. 1459 5

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine used in the treatment of serious conditions resulting from chemotherapy and bone marrow transplantation such as neutropenia and aplastic anemia. Despite these effects, GM-CSF has a very short biological half-life, and it requires frequent injection during the treatment. Therefore, the cytokine production is possible in the body with plasmid-encoded GM-CSF (pGM-CSF) coding for cytokine administered to the body. However, the selection of the proper delivery system for the plasmid is important. In this study, two different delivery systems, encapsulated plasmid such as fucoidan-chitosan (fucosphere) and chitosan microspheres, were prepared and the particle physicochemical properties evaluated. Fucospheres and chitosan microspheres size ranges are 151-401 and 376-681 nm. The zeta potential values of the microspheres were changed between 8.3-17.1 mV (fucosphere) and +21.9-28.9 mV (chitosan microspheres). The encapsulation capacity of fucospheres changed between 84.2% and 94.7% depending on the chitosan molecular weight used in the formulation. In vitro plasmid DNA release from both delivery systems exhibited slower profiles of approximately 90-140 days. Integrity of released samples was checked by agarose gel electrophoresis, and any additional band was not seen. All formulations were analyzed kinetically. The calculated regression coefficients showed a higher r2 value with zero-order kinetics. In conclusion, the characterizations of the microspheres can be modulated by changing the formulation variables, and it can be concluded that fucospheres might be a potential carrier system for the controlled delivery of GM-CSF encoding plasmid DNA.
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PMID:Comparison on in vitro characterization of fucospheres and chitosan microspheres encapsulated plasmid DNA (pGM-CSF): formulation design and release characteristics. 1985 14


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