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)

The cause of aplastic anemia associated with hepatitis (AAH) is as yet still unknown. There is a supposed relation to the immune mechanisms, however few reports have shown the effects of monocytes on the pathogenesis in the patients with AAH. We have reported a case of a 12-year-old boy with AAH related to cytomegaloviruses, and studied the hemopoietic progenitors. He showed pancytopenia and hypoplasia of the bone marrow on admission to our hospital. The culture studies showed that mononuclear cells (MNC) of the bone marrow produced few hemopoietic colonies in all cell lineages. However, the depletion of adherent cells from the MNC increased numbers of erythroid, neutrophil-macrophage and megakaryocyte colonies. Furthermore, the addition of adherent cells of the peripheral blood suppressed the colony formation in the aforementioned cell lineages by marrow MNC from which adherent cells, phagocytic cells and T-cells were abrogated. The results way suggest that monocytes play some soles in the pathogenesis of aplasia through inhibitor of hemopoiesis.
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PMID:[Suppression of in vitro hemopoiesis by the monocytes in a patient with aplastic anemia associated with hepatitis]. 131 81

The aim of this study was to evaluate the effect of stem cell factor (SCF) on the in vitro growth of bone marrow hematopoietic progenitors from patients with acquired severe aplastic anemia (AA) or Fanconi's anemia (FA). For this purpose, we studied 11 patients with acquired AA (5 at diagnosis, 6 after ALG treatment), 12 patients with FA, and nine normal controls. Bone marrow cells were plated in vitro for colony-forming unit granulocyte-macrophage (CFU-GM) (in the presence of granulocyte-macrophage colony-stimulating factor [GM-CSF]), and for burst-forming unit-erythroid (BFU-E) and CFU-granulocyte, erythroid, monocyte, megakaryocyte (CFU-GEMM) colonies (in the presence of erythropoietin and interleukin-3 [IL-3]), with or without 20 ng/mL of SCF. In normal controls, SCF enhanced the growth of CFU-GM colonies from 103 to 263 (median), of BFU-E from 168 to 352, and of GEMM colonies from 6 to 38/10(5) cells plated. In patients with acquired AA, SCF induced a significant enhancement of BFU-E growth (8 to 29; P = .01) and allowed the formation of GEMM colonies that were not scored in baseline culture conditions (0 to 8; P = .01). CFU-GM growth was enhanced (4 to 20), but not significantly (P = .3). This was true both for patients at diagnosis and after antilymphocyte globulin treatment. By contrast, 10 of 12 FA patients grew no CFU-GM, BFU-E, or CFU-GEMM colonies, with or without SCF. In two FA patients (one transfusion-dependent and one transfusion-independent), an enhancement of CFU-GM and/or BFU-E was observed. The lack of response of hematopoietic progenitor cells from FA patients to GM-CSF+SCF or IL-3+SCF was not dependent on a defective expression of cytokine receptor messenger RNAs. Northern blot analysis showed in marrow cells from acquired AA and FA patients the presence of normal transcripts for alpha- and beta-chains of GM-CSF/IL-3 receptor and for c-kit protein. In conclusion, SCF promotes the in vitro growth of hematopoietic progenitors in patients with acquired AA, but not in patients with FA, pointing out the intrinsic nature of the defect in the latter disorder.
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PMID:Effect of stem cell factor on colony growth from acquired and constitutional (Fanconi) aplastic anemia. 137 17

Subcutaneous administration of recombinant human Interleukin-1 beta (IL-1 beta) in a dose of 1-3 x 10(4) U/day for 14 to 72 days resulted in an increase in circulating granulocytes and bone marrow monocytes in all the 4 patients examined. Circulating platelet count was also increased in two of four patients with myelodysplastic syndrome (MDS) and aplastic anemia (AA). Bone marrow examination revealed an increase in megakaryocyte count in these patients, whereas the percentage of blast was not changed. An increase in blood platelet count was accompanied by an increase in serum GM-CSF in a patient with AA, whereas serum IL-6 level was not changed throughout the treatment with IL-1 beta. These findings suggest that IL-1 beta may be useful for the treatment of a proportion of patients with MDS and AA who are associated with thrombocytopenia.
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PMID:[Effect of subcutaneous administration of interleukin-1 beta on blood platelet count and serum GM-CSF in patients with myelodysplastic syndrome and aplastic anemia]. 143 38

We investigated the interactions between human erythropoietin (hEpo) and serum factor(s) on murine megakaryocyte (MK) colony formation. Serum-free cultures supported the growth of a large number of murine MK colonies in the presence of murine interleukin-3 (mIL-3). The addition of fetal calf serum (FCS) to mIL-3-containing cultures resulted in only a minimal increase in the number of murine MK colonies. In contrast, hEpo alone had no murine MK colony-stimulating activities in serum-free cultures. hEpo required the presence of FCS, murine serum, or human serum in cultures to promote murine MK colony growth and synergized with these sera to stimulate murine MK colony formation. Furthermore, sera from patients with aplastic anemia showed higher synergistic activities with hEpo than sera from hematologically normal persons (normal human serum). When normal human serum was fractionated by gel-filtration chromatography, two peaks with the synergistic activity were observed in the eluent. However, serum did not show any synergistic effects with hEpo on the growth of murine GM colonies or murine colony-forming unit-erythroid-derived colonies. Although human serum synergized with hEpo to stimulate murine MK colony formation, human cytokines such as IL-3, IL-4, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte-CSF (G-CSF) failed to induce murine MK colony formation in Epo-containing cultures. In cultures containing human IL-1 alpha + human IL-6 + hEpo as well as in cultures containing hEpo, human IL-3 and human GM-CSF failed to show stimulatory effects on murine MK colony formation. Moreover, the synergistic activity of human serum with hEpo could not be neutralized by antibodies such as antihuman IL-1 alpha, antihuman IL-3, antihuman IL-4, antihuman IL-6, antihuman G-CSF, and antihuman GM-CSF. Our data show that serum contains a growth factor(s) that synergizes with Epo to stimulate the proliferation and differentiation of MK precursors, and strongly suggest that this factor(s) is an unique growth factor(s) that is distinct from IL-1 alpha, IL-3, IL-4, IL-6, G-CSF, and GM-CSF.
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PMID:Interactions between recombinant human erythropoietin and serum factor(s) on murine megakaryocyte colony formation. 161 Oct 96

Regulation of megakaryocyte and platelet production remains poorly understood. In culture system two separate activities are needed for maximum production of megakaryocyte progenitors: promotor of clonal expansion and promoter of maturation, other growth factors and cells also contribute to regulation of megakaryocytopoiesis. Increased proliferation of megakaryocytes is observed in myeloproliferative disorders and idiopathic thrombocytopenic purpura, and decreased proliferation is found in aplastic anaemia and hypomegakaryocytic thrombocytopenia. Dysmegakaryocytopoiesis is present in myelodysplastic syndromes and acute leukaemia, and a proliferation of immature megakaryocytes in acute megakaryoblastic leukaemia. Increased understanding of human megakaryocytopoiesis is beginning to help in rational clinical management.
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PMID:Human megakaryocytopoiesis--normal and abnormal. 169 25

The hematopoietic growth factor interleukin (IL)-3 is a potent regulator of blood cell proliferation. It promotes the survival, proliferation, and development of hematopoietic stem cells and committed progenitor cells of the granulocyte-macrophage, erythrocyte, eosinophil, basophil, megakaryocyte, mast cell, and lymphocyte lineages. In addition, IL-3 enhances mature myeloid cell functions such as phagocytosis and activation of basophils and eosinophils, as well as monocyte cytotoxicity. The first phase of clinical trials suggested that IL-3 may augment myelopoiesis in a number of clinical conditions. It may be efficacious for treatment of primary marrow disorders, including myelodysplastic syndromes and aplastic anemia. However, replacement therapy with IL-3 alone is probably not sufficient to obtain maximal stimulation of myelopoiesis. Preclinical and clinical studies published to date suggest that sequential use or combinations of growth factors will be needed to obtain optimal hematopoietic responses.
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PMID:Interleukin-3. Its biology and potential uses in pediatric hematology/oncology. 178 68

The osteoclast derives from the haemopoietic stem cell but its relationship with the other progeny of the haemopoietic system is unknown. Osteoclast numbers were assessed in patients with aplastic anaemia and were found not to be depleted compared with a control population. This suggests that the osteoclast may develop along a separate lineage which is independent of the colony forming unit granulocyte, erythroid cell, monocyte, and megakaryocyte (CFU GEMM).
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PMID:The osteoclast, which derives from a haemopoietic stem cell, is not depleted in aplastic anaemia. 226 64

Anti-thoracic duct lymphocyte globulin (ALG) therapy is effective in patients with aplastic anemia. We examined the effect of ALG on human megakaryocyte progenitor cells (colony-forming unit-megakaryocyte, CFU-Meg) in vitro. Normal human bone marrow mononuclear cells (MNC) were cultured in plasma clots with varying concentrations of ALG or non-immunized horse IgG. After 12 days of culture, significant megakaryocyte colony formation was observed in cultures containing ALG but not in cultures containing non-immunized horse IgG. The peak stimulatory effect seemed to occur with 10-25 micrograms/ml of ALG. When marrow MNC, depleted of adherent and T cells, were cultured in plasma clots with ALG, its stimulatory effect on megakaryocytopoiesis decreased markedly. Finally, it was demonstrated that ALG stimulated marrow MNC to produce a factor stimulatory for CFU-Meg. The in vitro megakaryocytopoietic stimulatory effect of ALG may be related to its clinical efficacy in some patients with aplastic anemia.
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PMID:Anti-thoracic duct lymphocyte globulin stimulates human megakaryocytopoiesis in vitro. 231 70

Serial studies of bone marrow (BM) hematopoiesis using clonogenic assays were performed in an infant with congenital amegakaryocytic thrombocytopenia. Initially, when the only hematological abnormality was isolated thrombocytopenia, the number of clonogenic BM hematopoietic progenitors was comparable to controls, including the number of megakaryocyte precursors. As the disease evolved into aplastic anemia over an 11-month period, the peripheral blood counts declined, and colony numbers from four classes of BM progenitors--termed BFU-E, CFU-GM, CFU-Mix, and CFU-Meg--also declined in parallel. When added to the marrow cultures, patient's plasma was not inhibitory to either control or to patient's BM colony growth. Similarly, no cellular inhibition of hematopoiesis was observed when patient's BM was cultured after depleting the sample of T lymphocytes and after adding the T lymphocytes back. Furthermore, stromal cells established from short-term and long-term cultures of patient's BM showed normal proliferative activity and yielded a "fertile" marrow microenvironment for patient's and control BM colony growth. Our data suggest that the central problem in congenital amegakaryocytic thrombocytopenia is an intrinsic hematopoietic stem cell defect, rather than an abnormality of the marrow milieu. The findings are consistent with either a progressive, quantitative attrition of progenitors or their inability to proliferate into colonies in vitro and into differentiated, functional cells in vivo.
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PMID:Congenital amegakaryocytic thrombocytopenia: an intrinsic hematopoietic stem cell defect. 237 17

Urinary extracts from patients with aplastic anemia are known to promote murine megakaryocytopoiesis. In this report, we show a simple method for the partial purification of megakaryocyte colony-stimulating factor from human urine. A four-step purification procedure, which included ethanol precipitation, CM Affi-Gel Blue chromatography, wheat germ agglutinin-Sepharose chromatography and high-resolution hydroxyapatite chromatography, resulted in an about 430- to 630-fold increase of specific activity. The final fractions were still contaminated with erythropoietin, but the contaminated content of erythropoietin was not enough to stimulate mouse megakaryocytopoiesis in our culture system. We also demonstrate that human urinary extracts stimulated human megakaryocyte colony formation.
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PMID:Partial purification of human urinary megakaryocyte colony-stimulating factor. 278 50


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