Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of L1210 transplantable leukemic cells on in vitro formation of erythroid colonies from CD2F1 mouse bone marrow progenitor cells (CFU-E) was investigated. Clonal cell culture was carried out by a methylcellulose technique. Human urinary erythropoietin served as the stimulator. After 44 hours of incubation aggregates of eight or more erythroid cells were scored as colonies. The number of CFU-E which could be demonstrated in marrow cells from mice that had been injected intravenously 6 days before with 5 x 10(4) L1210 cells was far below that obtained from normal marrow cells. When 1.3 x 10(5) marrow cells from leukemic mice or L1210 ascites cells were cultured with an equal amount of normal cells, the number of CFU-E expressed was reduced by 51% and by 86%, respectively, relative to controls with normal cells only. Neither lethally irradiated L1210 cells (4500 rad) nor L1210 cell conditioned media suppressed erythroid colony formation. It is suggested that in L1210 leukemia erythropoiesis is decreased because of a cell-to-cell inhibitory action of the leukemia cells on CFU-E.
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PMID:Suppression of mouse erythroid colony formation by L1210 leukemia cells. 42 78

The clinical, hematologic and histologic characteristics of six patients with refractory anemia with deletion of the long arm of chromosome No. 5 are described. These patients had a distinct hematologic picture with macrocytic anemia of mild to moderate severity, normal to low leukocyte count and increased platelet count. The long arm of chromosome No. 5 was deleted in the majority of bone marrow metaphases. The main cause of anemia was underproduction with decreased erythroid precursors in the bone marrow and no increase in peripheral blood reticulocytes. Two of five patients responded transiently to the administration of androgens. In vitro evaluation of the bone marrow growth pattern in semisolid agar culture system was performed in three patients and was found to be normal and distinct from that in patients with preleukemia. In a follow up of up to five years, no patient had changed hematologically and in none had leukemia developed. The 5q-syndrome is a distinct hematologic entity and probably more common than hitherto realized. This diagnosis may have therapeutic and prognostic implications.
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PMID:Macrocytic anemia, thrombocytosis and nonlobulated megakaryocytes: the 5q-syndrome, a distinct entity. 45 27

Erythrokinetics were studied in 29 patients with hairy-cell leukaemia. In all cases there was an increase in plasma volume, closely correlated to the size of the spleen, indicating that the true degree of anaemia can only be appreciated by red cell volume measurement. Moderately increased haemolysis was observed in most cases, which did not correlate with the spleen size. Simultaneous study of autologous and isologous red cell life-span suggested an extra-corpuscular mechanism for the haemolysis in most patients. A quantitative erythropoietic defect, either relative or absolute, was found in half the cases, without any qualitative defect. Only one case showed erythroid metaplasia of the spleen. Thus marrow failure appears to be largely responsible for the anaemia and granulocytopenia in hairy-cell leukaemia. A clear correlation was shown between the short-term prognosis after splenectomy and the degree of hypersplenism. However, long-term survival correlated chiefly with the degree of bone marrow failure, whether splenectomy had been carried out or not. The results indicate that isotope studies in hairy-cell leukaemia are useful both in determining the best form of treatment and predicting survival.
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PMID:Erythrokinetic studies in hairy-cell leukaemia. 46 64

Infection of BALB/c mice with Rauscher leukemia virus (RLV) gives rise to pronounced erythrocytopoiesis manifesting in splenomegaly and is associated with progressive development of anemia. In the spleen erythroid colony forming units (CFU-E) increase exponentially up to 800-fold that of normal levels by the third week of infection. In vitro these CFU-E are dependent on erythropoietin for colony formation, their erythropoietin requirements being higher than that of CFU-E from normal mice. Numbers of CFU-E in spleen and degree of splenomegaly in anemic RLV infected mice were also shown to be modified by red blood cell transfusion, but progression of the disease was not stopped. Erythroid burst forming units (BFU-E) were also responsive to erythropoietin. However, a small proportion of cells also formed BFU-E colonies at concentrations which did not support growth of normal marrow BFU-E. When compared to normal, CFU-E found in RLV-infected spleen have similar velocity sedimentation rates. However, buoyant density separation of leukemic spleen cells indicated that CFU-E were more homogeneous (modal density 1.0695 g/cm3) than CFU-E from normal spleen. Analysis of physical properties of CFU-E and the nonhemoglobinized erythroblast-like cells, which accumulate in the spleen showed that they differed mainly in their distribution of cell diameter. Our findings show that erythroid progenitor cells in RLV infected mice are responsive to erythropoietin in vitro. Also in vivo erythropoiesis appears to be under control of erythropoietin but other factors which lead to progression of RLV disease apparently exist. Most proerythroblast-like cells, which are characteristic of this disease, apparently lack the potential to form colonies and may be more mature than CFU-E.
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PMID:Erythropoietin responses and physical characterization of erythroid progenitor cells in Rauscher virus infected BALB/c mice. 46 21

A group of mouse leukemia cell lines induced by the Friend murine leukemia virus (F-MuLV) was examined for a cell membrane antigens (regulated by the I-region of the H-2 complex), as well as for erythroid characteristics. Erythroid traits tested were hemoglobin synthesis, incorporation of 59Fe into heme, and presence of globin mRNA. Of 19 lines, 13 were positive for erythroid characteristics. All of these 13 lines were a-negative. Of 19 lines, 6 were negative for erythroid characteristics, and 5 of the 6 were a-positive. The data suggested that F-MuLV-induced leukemogenesis may operate in more than 1 cell type. In addition to the primitive erythroid type of cell usually involved in leukemia induced by F-MuLV, nonerythroid Ia-positive cells may also be transformed. The exact origin of the Ia-positive leukemia cells is unknown.
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PMID:Lack of erythroid characteristics in Ia-positive leukemia cell lines induced by Friend murine leukemia virus: brief communication. 56 10

Clinical and laboratory data are presented for two patients with a dyshaematopoietic disorder, and monosomy 7 in their bone marrow cells. The first patient, a 55-year-old woman, had been treated with chlorambucil for an ovarian carcinoma. After 4 years an oligoblastic myeloid leukaemia was diagnosed and she later died with an acute transformation of the disease. The second patient, a 21-year-old male, has had a dyserythropoietic anaemia with transient pancytopenia for over 5 years without any signs of malignancy. The possible relationship between therapy, the monosomy 7 and the other bone marrow abnormalities is briefly discussed. From an analysis of the data of these and comparable cases in the literature it appears that loss of chromosome No. 7 material is often associated with erythropoietic disorders such as erythroid hyperplasia and erythraemia. The reduction or absence of the Colton blood group antigens found in our patients and in a few other monosomy 7 cases also points to an abnormality of the red cell line.
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PMID:Monosomy 7 in two patients with a myeloproliferative disorder. 58 70

A variant of Rauscher leukemia virus, designated RLV-A, induced a slow progressive impairment of erythropoiesis in BALB/c mice. Identified in this study were a shortened red cell 51-cr half-time, anemia with indices showing minimal but significant hypochromia, ineffective erythropoiesis, and infiltration of the liver, spleen, and peripheral blood with erythroid pecursors. Ferrokinetic studies indicated a normal plasma iron turnover in infected mice but a decreased red cell iron turnover. Large amounts of 59Fe were taken up by the enlarged liver and spleen. Peak splenic heme 59Fe synthesis was delayed 12 hr in the infected mice. The substantial increase in the splenic intraerythrocytic nonheme iron pool and the hypochromic indices indicate a process analogous to that seen in the sideroblastic anemias. The disease produced by this RLV-A variant may prove useful for studying various aspects of the preleukemic sideroblastic anemias and DiGuglielmo syndrome.
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PMID:Erythrokinetics and ferrokinetics of a viral-induced murine erythroblastosis. 63 Jan 12

Cell proliferation was investigated in normal and Rauscher Leukemia Virus-infected BALB/c mice. Five days after inoculation, islands of leukemic blasts arose in the red pulp, and proliferated as shown by autoradiographic analysis after a pulse of 3H-Thymidine. These cells subsequently infiltrated the whole spleen and 3 weeks after infection about 60% of the spleen consisted of large immature erythroblast-like cells. Repeated injections of 3H-Thymidine led to uniform labeling of 85% of the spleen cells. Cell cycle analysis showed that for bone marrow as well as for spleen cells the total duration of the cell cycle did not differ from the cell cycle times of normal erythroblasts. From the difference between the actual doubling time and the potential doubling time (estimated on the basis of the cell cycle time) it can be calculated that considerable cell loss must occur. This cell loss is only to a minor extent due to the release of blasts into the peripheral blood. Probably cell death and extrusion of nuclei during erythroid differentiation are the main factors involved.
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PMID:The effect of Rauscher murine leukemia virus infection on the hemopoietic system of BALB/c mice. Cell proliferation and cell loss. 66 30

Bone marrow and spleen from Rauscher leukemia virus (RLV) infected BALB/c mice were tested for proliferative activity at various time intervals after infection using the spleen colony assay. Both bone marrow and spleen derived colonies showed a modified maturation behavior. The erythroid colonies were classified into three consecutive stages of maturation according to morphologic criteria. Both bone marrow and spleen derived erythroid colonies exhibited a retardation of maturation upon RLV infection of the donor mice; the spleen derived erythroid colonies showed the most severe changes. RLV itself could not mimic this phenomenon; moreover it was shown by immunofluorescence that only low amounts of RLV were present in the spleen colonies. It is therefore suggested that RLV modifies part of the stem cell compartment leading to a prolonged cycle time of proerythroblasts and hence to a retardation of colony growth.
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PMID:Modification of hemopoietic stem cells of BALB/c mice by Rauscher leukemia virus. 77 52

The study of Friend and Rauscher murine leukemia viruses has produced a variety of evidence regarding the nature of the target cell(s). These viruses produce in mice leukemias with a strong erythroid component. However, they are also pancytotic in their action, with demonstrable effects on differentiating myeloid and thromboid cells, the immuno-responsive cells, and the peripheral lymphoid cells as well. In addition, it has been noted that a variety of factors can influence disease expression, including the variety of mouse strain, the hematopoietic cell line being observed, and the tissue microenvironment in which leukemogenesis is taking place, as well as the viral substrain itself. The data available indicates that the target cells are definitely to be found among the most primitive of the hematopoietic progenitor cells of both the marrow and the spleen. However, from an analysis of this data it would appear that the virus target is not exclusively limited to a single type of hematopoietic precursor cell. Rather it is suggested that there is a closely related family of targets, consisting of the uncommitted pluripotent stem cell and the committed progenitor stem cells of the erythroid, myeloid, thromboid and immune cell lines. The evidence for each of these types of hematopoietic cells is reviewed.
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PMID:The role of committed and uncommitted hematopoietic stem cells as targets for Rauscher and Friend leukemia virus. 89 10


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