Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients infected with the human immunodeficiency virus (HIV) often present with neutropenia. To elucidate the mechanism(s) of this HIV-related neutropenia, we assessed the proliferative capacity of the granulocyte-macrophage progenitor cell (CFU-GM) from the bone marrow (BM) of 78 patients within the AIDS spectrum manifesting symptoms or signs related to HIV infection. Of these, 70 had a significant deficit in the growth of this committed progenitor when compared with normal controls (P less than .01). Further analysis revealed that the nucleated bone marrow cells from AIDS and AIDS-related complex (ARC) patients inhibited the growth of CFU-GMs from normal individuals when cocultured in agar (P less than .001). Control CFU-GMs were also inhibited when they were cultured over feeder layers containing patients' BM cells (P less than .001). Conditioned media obtained from the liquid culture of patients' BM cells did not inhibit normal control CFU-GM growth to a degree different from that of the cells themselves (P greater than .4). Analysis of these conditioned media by polyacrylamide gel electrophoresis (PAGE) revealed a unique glycoprotein (gp) with a mol wt of 84 kd. Further studies revealed that this gp possessed the inhibitory activity. These data suggest that this gp may be an important factor in HIV-related neutropenia. The presence of gp84 was independent of drugs administered to the patients.
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PMID:A glycoprotein inhibitor of in vitro granulopoiesis associated with AIDS. 366 34

Studies on proliferation and differentiation of granulocyte-monocyte progenitor cells in Chediak-Higashi syndrome (CHS) were done on a 1-month-old patient, using the soft-agar bone marrow culture technique. The number of granulocyte-macrophage colony-forming cells (GM-CFC) was markedly increased, but with a normal distribution into granulocyte, macrophage, or mixed colonies. Morphologic, cytochemical, and ultrastructural studies showed that 70% of the colonies consisted of cells with giant lysosomes typical of CHS, and in the remaining 30% abnormal cells were not detected. The supply of granulocyte-macrophage colony-stimulating factor (GM-CSF) by the patient's peripheral blood leukocytes was markedly decreased. Inhibition of normal in vitro granulopoiesis by the patient's lymphocytes or serum was not demonstrated. It appears that granulocyte progenitors in CHS proliferate normally, or even in excess, probably in response to intramedullary destruction of granulocytes. The majority of the progenitors are intrinsically defective and give rise to colonies that contain the abnormality. In others the defects are unidentifiable, probably due to the immaturity of the specific fusion process of the cytoplasmic granules. The abnormal leukocytes in CHS are also defective in their capacity to provide GM-CSF, and this may account in part to the overt neutropenia. These studies demonstrate that the basic cytoplasmic abnormalities of the granulocytes and monocytes in CHS are embedded in the granulocytic-monocytic committed stem cell.
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PMID:Chediak-Higashi syndrome. Expression of the cytoplasmic defect by in vitro cultures of bone marrow progenitors. 374 Mar 66

Mice exposed to high concentrations of ethanol vapour (25-38 mg/l of inhaled air) for 24 h develop leucopenia, neutropenia, lymphopenia, monocytopenia and thrombocytopenia but not anaemia or macrocytosis. Their bone marrows usually give normal deoxyuridine-suppressed values and contain normal numbers of granulocyte-macrophage progenitor cells and slightly reduced numbers of megakaryocytes. Mice exposed to lower concentrations of ethanol vapour (10-25 mg/l of inhaled air) for 20-43 days develop thrombocytopenia only and, like the mice exposed for 24 h, do not develop anaemia or macrocytosis. The bone marrows of mice exposed to ethanol for 24 h or for 20-43 days, did not show either megaloblastic or sideroblastic erythropoiesis. The data suggest that the ethanol-treated mouse may provide a useful model for the investigation of the mechanisms underlying some but not all of the ethanol-induced haematological changes seen in humans.
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PMID:Haematological abnormalities in mice continuously exposed to ethanol vapour. 380 Dec 97

Chloramphenicol, an antibiotic associated with reversible bone marrow suppression and fatal aplastic anemia, was found to increase human bone marrow granulocyte-macrophage colonies (CFU-GM) in vitro. Maximal stimulation was at a concentration of 1.0 micrograms/ml (3.1 microM), with inhibition at concentrations greater than 10 micrograms/ml. This effect was noted in normal donors and in children with neutropenia of various etiologies. Stimulation was ablated by depletion of bone-marrow-adherent cells and was restored by addition of peripheral-blood-adherent mononuclear cells. The stimulatory effect appears to be specific for chloramphenicol, as numerous structural analogues of chloramphenicol, including its three stereoisomers, did not show stimulation. The stimulation was present at plateau concentrations of colony-stimulating activity, suggesting that the stimulatory effect is not due to elaboration of excess colony-stimulating activity by chloramphenicol. We hypothesize that low concentrations of chloramphenicol stimulate CFU-GM by a highly specific interaction with adherent mononuclear cells and elaboration of an undefined growth factor.
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PMID:Stimulation of human committed bone marrow stem cells (CFU-GM) by chloramphenicol. 394 70

The effects of branched-chain amino acid metabolites on granulocyte-macrophage progenitor cell proliferation in marrow culture are reported. Isovalerate and propionate profoundly suppress granulopoiesis at both 3.2 and 6.4 mM concentrations, whereas methylmalonate and other metabolites suppress to a lesser degree. The parent branched-chain amino acids leucine, isoleucine, and valine do not suppress in vitro granulopoiesis at similar concentrations. Because the concentrations of the organic acids tested fall within the pathophysiologic ranges observed in patients with isovaleric, propionic, and methylmalonic acidemias, we suggest that elevated in vivo levels of isovalerate, propionate, and to a lesser degree methylmalonate are responsible for the neutropenia observed in these disorders.
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PMID:Suppression of granulopoietic progenitor cell proliferation by metabolites of the branched-chain amino acids. 396 82

Three patients had leukocytosis of large granular lymphocytes and chronic neutropenia. Clonal chromosomal abnormalities (trisomy 8 and trisomy 14) and lymphocytic infiltration of splenic red pulp, hepatic sinusoids, and bone marrow indicated the neoplastic nature of the large granular lymphocytes. Demonstration of a T3+, T8+, HNK-1 + phenotype and low natural killer cell activity that was augmented by interferon treatment showed the leukemic cells to be immature natural killer cells. Multiple autoantibodies were present and included rheumatoid factor and antinuclear, antineutrophil, antiplatelet, and antierythrocyte antibodies, suggesting a defect of B-cell immunoregulation. In addition, in-vitro studies showed impaired suppression of immunoglobulin biosynthesis by abnormal cells from one patient. Antineutrophil antibodies and absence of direct cell-mediated inhibition of granulocyte-macrophage colony formation supported a humoral immune mechanism for the neutropenia. In these patients the syndrome of splenomegaly, multiple autoantibodies with neutropenia, and lymphocytosis of large granular lymphocytes is due to a neoplastic proliferation of immature natural killer cells.
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PMID:Leukemia of large granular lymphocytes: association with clonal chromosomal abnormalities and autoimmune neutropenia, thrombocytopenia, and hemolytic anemia. 396 54

Myelopoiesis and marrow adherent cells were evaluated in C57Bl/6J mice at two and four weeks after treatment with 0.1 mg 17 beta-estradiol cyclopentylpropionate. Estradiol-treated mice were lymphopenic and eosinopenic at two and four weeks; in addition, neutropenia occurred at four weeks. Numbers of lymphoid, granulocytic, and erythroid cells were decreased in the marrow at two and four weeks. The numbers of granulocyte-macrophage and fibroblast colony-forming units in the humeral marrow were also decreased at two and four weeks. However, the hematopoietic ability of marrow adherent cells was unchanged in estradiol-treated mice. Thymic cortical atrophy, metaphyseal osteosclerosis, and neutrophilic infiltration of the uterus occurred in estradiol-treated mice.
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PMID:Myelopoiesis and marrow adherent cells in estradiol-treated mice. 403 44

Bone marrow and peripheral blood cells of patients with non-leukemic neutropenia contain and elaborate a granulocyte-progenitor cell inhibitory activity. The inhibitory activity is common to the neutropenias of the various etiologies studied, which included congenital, idiopathic, autoimmune, cyclical, common variable immuno-deficiency with hypogammaglobulinemia and drug induced states. It derives from non-adherent, low density, slowly sedimenting and non-E-rosetting cells and appears to require RNA and protein synthesis, but not cell division, for its production. The material is not species specific, inhibits autologous and allogeneic normal CFUgm and leukemic CFUgm, is not cell-cycle specific in action and is most effective against granulocyte colony forming cells (CFUg), less effective against mixed granulocyte-macrophage colony forming cells (CFUgm) and least or non-effective against macrophage colony forming cells (CFUm). This inhibitory activity has no influence on cells which generate CFUc in suspension culture or on the erythroid colony forming (CFUe) and burst forming (BFUe) units. It is different from other known inhibitory activities such as lactoferrin, leukemia inhibitory activity, E type prostaglandins, interferon and immunoglobulins. This inhibitory activity, while at present an in vitro phenomenon, may be produced as a secondary response within a compromised host.
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PMID:Specific inhibitory activity against granulocyte-progenitor cells produced by non-T lymphocytes from patients with neutropenia. 616 31

We report a case of dyskeratosis congenita ( DCG ) with neutropenia, lymphocytopenia and thrombocytopenia. Peripheral blood T lymphocytes (T cells) were proved to have a suppressive effect on the colony forming unit granulocyte-macrophage (CFU-GM). Splenectomy caused a transient increase of neutrophil count with the disappearance of the suppressive T cell activity. However, pancytopenia recurred without re-appearance of suppressive T cell activity.
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PMID:Bone marrow failure in dyskeratosis congenita. 623 93

A case of T cell chronic lymphocytic leukaemia (CLL) with red cell hypoplasia and neutropenia is reported. WBC was 10.0 X 10(9)/l with 78% being T lymphocytes. These T lymphocytes were positive for Fc gamma receptor and had OKT8 and Leu 2a antigens on the cell surfaces. They suppressed both erythroid and granulocyte-macrophage colony formation in normal bone marrow cultures and suppressed immunoglobulin production by normal B lymphocytes in vitro. Though the myeloid cells were preserved in the bone marrow and the values of serum immunoglobulins were within normal limits, it can be estimated from these results that red cell hypoplasia and neutropenia were partially due to the suppression of haemopoietic precursor cells by leukaemic T lymphocytes.
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PMID:Suppressor T cell chronic lymphocytic leukaemia associated with red cell hypoplasia. 623 67


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