Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An in vitro hematopoietic microenvironment was established from explained fragments of bone marrow from adult noninbred NIH Swiss mice with the use of corticosteroid-reconstituted horse serum. Infection with Kirsten murine sarcoma virus (Ki-MuSV) with either a Rauscher murine leukemia virus (R-MuLV) or Balb:virus-1 helper virus coat reduced proliferation of granulocytic and pluripotent hematopoietic stem cells and produced neoplastic transformation of both macrophages and preadipocytes in the adherent cell population within a 4-week period. Ki-MuSV-transformed, virus-releasing macrophages formed clusters of 4-49 cells in 0.8% methylcellulose-containing medium in the absence of added colony-stimulating factor (CSF), synthesized lysozyme, ASD-chloroacetate substrate-specific esterase-M, and CSF, and produced tumors following inoculation iv into adult NIH Swiss mice or ip into newborn NIH Swiss mice. In cultures infected with helper leukemia viruses R-MuLV or Balb:virus-1, gradual transformation of a distinct cell phenotype was observed over a 9-week period with generation of increasing numbers of atypical myeloblasts and promyelocytes which showed dyssynchronous nuclear-cytoplasmic maturation, basophilic granulation, cytoplasmic vacuolation, and formation of incompletely maturing CSF-dependent granulocyte-macrophage colonies in vitro and small spleen colonies in vivo. These data demonstrated that rapid biologic expression of the murine sarcoma virus genome in specific adherent "stromal" marrow cells prevents detection of a more subtle helper-virus-induced dysmyelopoiesis in a distinct nonadherent cell population.
 ...
PMID:Phenotypically distinct target cells for murine sarcoma virus and murine leukemia virus marrow transformation in vitro. 21 35

Hematopoietic growth factors were found as factors stimulating hematopoietic colony formation in in vitro culture system using bone marrow cells as a source of hematopoietic progenitor cells. Erythropoietin, a growth factor stimulating erythroid lineage has now been clinically used as an therapeutic agent for anemia of chronic renal failure. Macrophage colony-stimulating factor (M-CSF), a growth factor stimulating the production of leukocytes including monocytes and neutrophils has been clinically used as an agent for leukopenic patients after anti-cancer therapy. M-CSF improves a survival rate after bone marrow transplantation (BMT) through the reduction of mortality rate associated with BMT such as bleeding, engraftment failure and GVHD. M-CSF accelerated platelet production when injected to thrombopenic patients with solid tumor after anticancer therapy. Granulocyte CSF (G-CSF) is a most powerful agent for various kinds of neutropenia such as neutropenia after anti cancer therapy, neutropenia after BMT, aplastic anemia, chronic neutropenia of children and myelodysplastic syndrome. However, since G-CSF stimulates growth of leukemic cells in vitro, careful observations should be required when clinically used on leukemic patients. Clinical studies of granulocyte-macrophage CSF (GM-CSF) and interleukin 3 (IL-3) are now in progress, in which a promoting activity of leukocyte production of these factors is evaluated.
 ...
PMID:[Clinical application of hematopoietic growth factor (IL-3, G-CSF, GM-CSF, and EPO)]. 127 40

Sera of 25 healthy controls and 75 patients suffering from myelodysplastic syndromes (MDS) were investigated for serum concentration of interleukin-1 alpha (IL-1 alpha), IL-3, IL-6, granulocyte-colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), erythropoietin (Epo), and tumor necrosis factor-alpha (TNF-alpha). According to French-American-British (FAB) classification, 21 refractory anemia (RA), seven refractory anemia with ring sideroblasts (RARS), 15 chronic myelomonocytic leukemia (CMML), 12 refractory anemia with excess of blasts (RAEB), and 20 RAEB in transformation (RAEBt) were examined. TNF-alpha levels were inversely correlated with lower levels of hemoglobin concentration (r = -0.31, p = 0.005), irrespective of the requirements for transfusion in anemic MDS patients. Significant differences in TNF-alpha levels between CMML (26.2 +/- 5.9 pg/ml) and the FAB subgroups (16.1 +/- 1.6 pg/ml) were detected. There was an overall inverse relationship between the level of erythropoietin and the degree of anemia, but a wide range of Epo response between patients with similar hemoglobin concentrations. Serum levels of IL-1 alpha and GM-CSF were undetected in most of the patients. In 57% of the samples there were detectable levels of G-CSF, without a correlation of the serum levels with blood cell counts, nor with any of the FAB subcategories. Overall, 29% and 25% of the patient sera exhibited elevated IL-3 and IL-6 levels, respectively. There was no correlation of the serum levels with any of the blood counts, other cytokines, nor FAB subcategories. In conclusion, simple negative feedback mechanism between a specific cytokine and the production of blood cells seems not to be the case in MDS, except for red cell production and erythropoietin concentration. Our data may suggest the involvement of TNF-alpha in the pathogenesis of anemia in MDS.
 ...
PMID:Measurement of serum cytokine levels in patients with myelodysplastic syndromes. 128 Jul 51

An immunohistochemical and morphometric study was performed on trephine biopsies of the bone marrow in 52 patients (28 males/24 females; age 68 years) with various subtypes of myelodysplastic syndromes (MDS) to determine the number of macrophages (phagocytic-histiocytic reticular cells). Quantifications included the haemosiderin-storing subpopulation (Prussian-blue reaction) of this lineage as well as the iron-free compartment. The latter was identified by a new monoclonal antibody (PG-M1) which is specifically directed against histiocytic reticular cells. Bone marrow specimens of individuals without haematological disorders and those showing reactive lesions served as controls. In comparison with the normal bone marrow and inflammatory changes (i.e. rheumatoid arthritis) 23 of the 52 patients with MDS revealed a significant increase in macrophages. This increase encompassed not only the iron-laden subpopulation but also the total number of phagocytic reticular cells. Accumulation of macrophages in MDS was speculated to be due to a premature and enforced degradation of dysplastic cell elements leading to phagocytosis of haemosiderin and debris material. Moreover, cells of the monocyte-macrophage system could be involved in the complex pathomechanism of fibrillogenesis, since in a considerable percentage of patients with MDS, an increase in reticulin (argyrophilic) fibres was noticeable. Our finding of an expansion of the macrophage compartment in about half of the patients with MDS is in keeping with results of cell culture studies on colony formation of granulocyte-macrophage precursors (CFU-GM).
 ...
PMID:Macrophages (phagocytic-histiocytic reticular cells) in reactive-inflammatory lesions of the bone marrow and in myelodysplastic syndromes (MDS). An immunohistochemical and morphometric study by use of a new monoclonal antibody (PG-M1). 130 Jun 12

This investigation is retrospective and comprises 20 patients with bone-marrow insufficiency. During the period 1.4.1988-1.3.1991, these patients were treated with erythropoietin (Epo), the granulocyte-macrophage-colony-stimulating factor (GM-CSF) or the granulocyte-colony-stimulating factor (G-CSF). Thirteen patients had primary bone-marrow insufficiency: six had the myelodysplastic syndrome, three had primary myelofibrosis, two aplastic anemia and two myelomatosis. On account of dominating symptoms of anemia, five patients received Epo while eight received GM-CSF as part of an extensive clinical trial of this preparation. Seven patients with relapse of the haematological malignant disease had bone-marrow insufficiency and pancytopenia secondary to intensive chemotherapy/irradiation: four of these patients received GM-CSF and two received G-CSF with the object of increasing bone-marrow regeneration and to render further chemotherapy possible. One patient received GM-CSF with the object of improving bone-marrow function after autologous bone-marrow transplantation. Treatment with Epo for ten months combined with treatment with interferon for six months resulted in normalization of the haemoglobin concentration in one patient with bone-marrow insufficiency on account of primary myelofibrosis. Treatment with Epo for briefer periods in lower doses was without effect in four other patients with primary bone-marrow insufficiency. Treatment with GM-CSF and G-CSF resulted in neutrophil leukocytosis in 12 out of 15 patients (80%) and, in six out of 14 patients (43%), increased marrow cellularity was demonstrated by means of histological examination of the bone-marrow. One patient showed normal haemoglobin levels during treatment with GM-CSF.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Hematopoietic growth factors in primary and therapy-related bone marrow insufficiency]. 137 68

Human urinary macrophage colony-stimulating factor (hM-CSF) is a glycoprotein with a molecular weight of 85 kDa which consists of two homologous subunits with a molecular weight of 43 kDa. It stimulates monocyte production through the stimulation of progenitor cells to differentiate to mature monocytes as well as neutrophil production through the stimulation of mature monocytes to produce granulocyte-macrophage and granulocyte CSF. It also enhances platelet production through the production of megakaryocyte potentiator (Meg-POT). Recently, proteoglycan type M-CSF has been found by our group. This type of M-CSF has a molecular weight of greater than 200 kDa and consists of a 43 kDa subunit and a 150-200 kDa subunit, the latter of which contains chondroitin sulfate glycosaminoglycan. This proteoglycan type M-CSF binds to extra-cellular matrix at the part of glycosaminoglycan. In addition to hematopoiesis-stimulating activity, M-CSF has a promoting activity on monocyte tumor-killing, osteoclast production and differentiation of cytotrophoblasts to syncytiotrophoblasts which secrete gonadotropin. M-CSF receptor (M-CSF-R) was found as a product of proto-oncogene, c-fms which consists of 972 amino acids. Mutations at Tyr 969 and Ser 301 of M-CSF-R has been found in patients with myelodysplastic syndrome and monocytic leukemia.
 ...
PMID:[Function,molecular structure and gene expression of macrophage colony-stimulating factor]. 143 77

Plasma lactoferrin content was measured before and after therapy with recombinant granulocyte-macrophage colony-stimulating factor in five patients with aplastic anaemia, six with myelodysplasia, and three with prolonged, severe, chemotherapy-induced neutropenia. Before therapy plasma lactoferrin content was uniformly low. However, patients with aplastic anemia and those with chemotherapy-induced neutropenia had a normal lactoferrin:neutrophil ratio. The low levels of plasma lactoferrin thus reflected the low granulocyte mass. On the other hand, patients with myelodysplasia also had reduced lactoferrin:neutrophil ratios, suggesting qualitative/quantitative abnormalities of neutrophil lactoferrin production. After treatment with granulocyte-macrophage colony-stimulating factor, plasma lactoferrin levels increased in patients with aplastic anemia and in those with chemotherapy-induced neutropenia who showed a neutrophil response to treatment. In these patients, the lactoferrin:neutrophil ratio became elevated, suggesting increased synthesis/release of lactoferrin from neutrophils. However, patients with myelodysplasia continued to show depressed lactoferrin:neutrophil ratios, even when there had been an increase in granulocyte count, suggesting persistent abnormalities of neutrophil lactoferrin production/release. The implications of these findings for treatment of neutropenic patients with granulocyte-macrophage colony-stimulating factors are discussed.
 ...
PMID:Plasma lactoferrin content in neutropenic patients: effects of treatment with recombinant granulocyte-macrophage colony-stimulating factor. 151 94

We studied myelodysplastic syndrome-associated inhibitory activity (MDS-IA), which inhibited colony formation in vitro of normal granulocyte-macrophage progenitors (CFU-GM). When adherent marrow cells were incubated with fetal calf serum for 21-24 d, monocyte-derived lipid containing huge macrophages (MDLM) developed. MDLM from MDS marrow (MDS-MDLMs) and their conditioned medium (MDLM-CM) consistently suppressed the growth of normal CFU-GM colony formation. MDS-IA was active on CFU-GM during the S-phase and relatively resistant to heating. Monoclonal antibody against H subunit (acidic) ferritin and polyclonal antibody against placental ferritin neutralized the inhibitory activity of MDS-MDLMs. In addition, cell lysates of MDS-MDLMs reacted to both monoclonal anti-H subunit ferritin and polyclonal anti-placental ferritin in Western blotting analysis, indicating that the inhibitory activity was predominantly acidic isoferritin. On the other hand, MDLMs obtained from normal bone marrow had a CFU-GM enhancing activity. These results suggest that MDS-MDLMs may be responsible for the suppression of granulopoiesis in patients with MDS and that the suppression may be mediated by soluble factors, notably H subunit isoferritin.
 ...
PMID:Myelodysplastic syndrome (MDS)-associated inhibitory activity on haematopoietic progenitor cells: contribution of monocyte-derived lipid containing macrophages (MDLM). 152 Jun 27

Four-stem-cell assays, which evaluate megakaryocytic (CFU-Meg), immature and mature erythropoietic (BFU-E, CFU-E), and granulocyte-macrophage (CFU-GM) colony formation, were performed in nine patients with myelodysplastic syndromes (MDS). The CFU-Meg, BFU-E, and CFU-E colony growths were disturbed more often than the CFU-GM colony formation. A CFU-E increase was not recognized in most MDS patients, but a dose-dependent increase of bone marrow CFU-Es in response to erythropoietin (EPO) was recognized only in two refractory anemia (RA) patients whose CFU-Es were more than one tenth of normal controls. One patient with RA and the other with chronic myelomonocytic leukemia (CMML), both of whose bone marrow CFU-Es did not increase at the higher dose of EPO in vitro, were treated with recombinant human EPO (rHuEPO), resulting in no effects. The responsiveness of patients with MDS to various recombinant hemopoietic factors might be predicted by both the residual degree of bone marrow hematopoietic precursor cells and the response of stem cells to the higher doses of each hemopoietic factor.
 ...
PMID:Three-lineage hemopoietic precursor cells and effectiveness of recombinant human erythropoietin in patients with myelodysplastic syndromes. 158 47

Recombinant human colony-stimulating factors (CSFs) have potential for wide use in the areas of oncology and infectious disease. Granulocyte CSF and granulocyte-macrophage CSF currently are approved for use in the treatment of neutropenia associated with standard-dose cancer chemotherapy and bone marrow transplantation, respectively. Other settings in which these agents have shown promise are dose-intensive chemotherapy, enhancement of progenitor cell support, primary and acquired neutropenias, myelodysplasia, aplastic anemia, and cytopenias associated with human immunodeficiency virus infection or myelosuppressive therapies for such infection or related conditions. Clinical findings in these areas are encouraging, and potential exists for additional applications of the CSFs.
 ...
PMID:Colony-stimulating factors: clinical applications. 159 11


1 2 3 4 5 6 7 8 9 10 Next >>