Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sixty-six adults were studied with the aim of establishing positive diagnostic criteria for myeloproliferative disease. Erythroid colony formation from peripheral blood progenitors was assayed in a serum-free culture system with the addition of recombinant human growth factors. Endogenous colonies were more frequent in myeloproliferative disease than controls. The mean number of clusters per erythroid burst (BFU-e) in cultures with erythropoietin only was lower in primary proliferative polycythemia (polycythemia vera, PPP) than controls. In PPP, primitive BFU-e demonstrated greater dependence on interleukin 3 than controls, and mature BFU-e more susceptibility to inhibition by alpha-interferon. The findings indicate an abnormal response to several different cellular messengers in PPP, and permit an effective diagnostic discrimination from non-clonal polycythemias.
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PMID:Sensitivity of erythroid progenitors to recombinant growth factors in the diagnosis of myeloproliferative disorders. 232 55

KMOE-2/05, a continuous human erythroid cell line derived from a patient with acute erythremia was capable of differentiating into benzidine positive cells following exposure to cytosine arabinoside (CA), mitomycin C, or daunorubicin. Among the three substances, CA was the most effective inducer. Other compounds, reported as effective inducers on human and murine erythroid cells, were also tested but they were ineffective. Benzidine positive cells were counted to be approximately 500/1 X 10(5) cells after 10 days incubation with CA at its optimal concentration of 1 X 10(-5) M. Under the same conditions, the hemoglobin (Hb) concentration quantitated by radioimmunoassay (RIA) was more than 500 ng/1 X 10(6) cells. Quantitative kinetics of synthesized Hb and of benzidine-positive cell counts, after exposure to CA were closely correlated.
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PMID:In vitro differentiation of a human erythroid cell line (KMOE) induced by some metabolic inhibitors. 241 64

Induction of globin gene expression in KMOE cells derived from a patient with acute erythremia was studied by Northern blot and S1 analysis. KMOE cells exposed to cytosine arabinofuranoside (Ara-C) synthesized beta-globin gene transcripts, however, in the presence of hemin gamma-globin gene transcripts. An increase in alpha-globin gene transcripts was also detectable in KMOE cells treated with both Ara-C and hemin. Upon exposure to hemin after exposure to Ara-C, or exposure to Ara-C after hemin, there was a 5-10-fold increase in gamma-globin gene transcripts compared to that of cells induced by hemin alone. Neither epsilon nor zeta globin transcripts were detected. The KMOE cell line, therefore, exhibits phenotypic properties of adult and fetal erythroid cells.
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PMID:Differential induction of adult and fetal globin gene expression in the human erythremia cell line KMOE. 244 37

Erythropoietic progenitors from bone marrow of patients with polycythemia vera (PV), secondary polycythemia (SP) and healthy subjects (HS) were cultured in plasma clot diffusion chambers in vivo. The chambers were inserted into the peritoneal cavities of rats, which 24 and 2 h before implantation received an injection of phenylohydrazine. Control experiments were done without erythropoietin (Epo) stimulation. Colonies after 2 and 7 days of culture were considered to be formed by mature erythropoietic progenitors (CFU-D-E) and burst forming cells (BFU-D-E), respectively. PV-erythroid progenitors, both BFU-D-E and CFU-D-E produced markedly more colonies than those from SP and HS, especially in experiments without Epo stimulation (p less than 0.01). The plating efficiency in SP was comparable to that noted in HS (p greater than 0.05). These results have led us to postulate that the study of erythroid progenitor clonal proliferation in plasma clot diffusion chamber can be helpful in the differential diagnosis of PV and SP, when other clinical and laboratory findings are not sufficiently convincing.
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PMID:Usefulness of the assessment of erythroid progenitors growth for differential diagnosis of primary and secondary polycythemias. 244 2

The role of erythropoietin (EP) in polycythemia vera (PV) is controversial, with some experiments suggesting that erythroid progenitors in PV are exquisitely sensitive to EP and EP dependent, and others suggesting that PV progenitors are EP independent. We have examined the characteristics of the EP receptor (EP-R) on erythroid colony-forming cells (ECFC) from patients with PV. In contrast to normal ECFC, which have two classes of EP-R, with 20% showing high affinity (Kd = 0.13 nM; range, 0.04-0.20 nM) and the remainder lower affinity (Kd = 0.37 nM; range, 0.28-0.57 nM), PV ECFC show a single class of 851 low affinity EP-R with Kd = 0.72 nM (range, 0.36-0.85 nM). ECFC from patients with secondary (EP driven) polycythemia or anemia show two classes of EP-R (Kd = 0.18 and 1.10 nM, respectively). Attempts to remove tightly bound EP from putative high affinity EP-R in PV did not reveal any higher affinity receptors. Determination of molecular size by crosslinking showed two proteins of 90 and 100 kD similar to those seen with normal EP-R. These studies indicate the PV ECFC have EP-R that are structurally similar to normal EP-R but lack the higher binding affinity for EP.
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PMID:Erythropoietin receptors in polycythemia vera. 255 27

Erythroblastic islands (EI) available for light-microscopic study were obtained from 25 patients with a haemopoiesis pathology from the ileum bone using the method suggested by the authors. Erythropoiesis activation in the osteomyelofibrosis in the erythremic stage, erythremia and haemolytic anemia was followed by the appearance in the "crown" of the central macrophage from 34 to 37 nucleated erythroid cells, enhanced phagocytosis of the normoblast nuclei and the presence of 2-4 nucleoli in the macrophage and proerythroblast nuclei.
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PMID:[Morphology of erythroblastic bone marrow islands in hematologic patients]. 259 84

The authors presents her experience in polycythaemia rubra vera. A number of 20 cases have been studied, with a peak of polycythaemic values of 20.6/dl for the Hb, a Ht of 80%, an WBC count of 28,000/cmm and a platelet count of 1,400,000/cmm. The following peculiarities of the cases should be underlined: 1. the personal and hereditary collateral antecedents which reveal a significant pathological background; 2. the very slow evolutive potential of the malignant erythroid clone, which permitted a quasi-normal way of life for many years; 3. a careful therapy, differentiated with respect to the evolutive stage of disease, which resulted in a long survival (over 17 years).
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PMID:Polycythaemia rubra vera. Analysis on 20 cases. 263 48

Megakaryocyte colony formation, as identified by conventional techniques, was observed in precursor cell cultures from peripheral blood in 8 of 20 consecutive patients with diagnosis of myeloproliferative disease (4/11 patients with polycythemia vera, 3/5 with essential thrombocythemia, 1/2 with primary osteomyelofibrosis and 2 with a myeloproliferative syndrome not further assessable), but not in 50 healthy controls (p less than 0.0001). 7 cultures showed spontaneous erythroid colonies, but were negative for megakaryocyte colonies. Megakaryocyte colony formation was independent of added erythropoietin, plasma or human leukocyte-conditioned medium, but was dependent on the presence of accessory cells. The cells in megakaryocyte colonies had the characteristic morphology of megakaryocytes and stained positively with the IIIa/IIb monoclonal anti-platelet antibody. Thus, megakaryocyte colony formation by precursor cells from peripheral blood in the absence of exogenous stimulating factors seems to be a phenomenon specific for myeloproliferative disease. Differential diagnosis of thrombocythemia may be facilitated by demonstration of endogenous megakaryocyte colony formation, which does not occur in secondary disease.
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PMID:Endogenous megakaryocyte colonies from peripheral blood in precursor cell cultures of patients with myeloproliferative disorders. 265 91

To further define the growth factors required for the in vitro proliferation of erythroid progenitors in polycythemia vera (PV), we have compared the ability of interleukin 3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) to support the growth of erythropoietin (Epo)-dependent and -independent erythroid colony formation. By using nonadherent mononuclear cells from peripheral blood, Epo-dependent colony formation was enhanced by IL-3 and GM-CSF in PV patients. Comparable results were obtained with normal erythroid progenitors. Augmenting effects of IL-3 and GM-CSF were observed on spontaneous erythroid colony formation, i.e., erythroid colony formation in the absence of exogenous supplied Epo. This was not due to a small amount of Epo in the culture media because an anti-Epo antibody did not prevent endogenous colony formation, nor did it prevent the enhancing effects of IL-3. Finally it was observed that in contrast to IL-3, monocyte depletion was required for the enhancing effects of GM-CSF on erythroid colony formation. These results provide evidence that endogenous colony formation in PV is independent of Epo but can be augmented by IL-3 or GM-CSF.
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PMID:In polycythemia vera human interleukin 3 and granulocyte-macrophage colony-stimulating factor enhance erythroid colony growth in the absence of erythropoietin. 267 32

The ability of erythroid cultures to distinguish among myeloproliferative disorders was examined. We studied 14 patients with polycythemia vera (PV), 11 with chronic myelogenous leukemia (CML), four with non-PV erythrocytosis, two with agnogenic myeloid metaplasia, as well as three normal fetuses and greater than 25 normal adults. Endogenous, i.e. grew without added erythropoietin, bone marrow CFU-E-derived colonies were observed in all but one PV patient. However, endogenous blood BFU-E-derived bursts were observed in only eight of 14 PV patients. Endogenous erythroid colonies were not seen in cultures from any normal adults or fetuses, or patients with CML, erythrocytosis, or myeloid metaplasia. In PV, relative HbF synthesis was always greater in cultures without erythropoietin, while in cultures from all other patients relative HbF synthesis was similar to that observed in cultures from normal individuals. We conclude that PV and CML are distinguishable in culture since CML patients do not have endogenous growth. Most important, endogenous bone marrow CFU-E-derived colonies are the only consistently unique observation in patients with PV, and endogenous CFU-E- and BFU-E-derived colonies and bursts are not uniformly observed in PV blood cultures. In-vitro studies of erythropoiesis to confirm the diagnosis of PV, therefore, require marrow when endogenous colonies and bursts are absent from blood cultures.
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PMID:Comparison of erythroid progenitor cell growth in vitro in polycythemia vera and chronic myelogenous leukemia: only polycythemia vera has endogenous colonies. 271 48


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