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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ultrastructural studies were performed on blood samples from five neonates with Down's syndrome and transient abnormal myelopoiesis (TAM). Three methods of fixation were employed to detect diaminobenzidine (DAB) reactivity. The first method used glutaraldehyde solution, while the second and third methods used tannic acid-glutaraldehyde mixtures. Before fixation by the second method, specimens were washed in order to eliminate plasma, and before fixation by the third were diluted to lessen the effects of plasma protein. The latter two methods were more sensitive than the first for detection of DAB reactivity, while the third also resulted in better preservation of morphology than did the second. Even the first method was able to detect DAB reactivity in cells of megakaryocyte-platelet series in appropriate sections. Although the majority of blasts appeared with light microscopy to be undifferentiated, their ultrastructural morphology and ultrastructural cytochemistry were in fact found to be quite heterogeneous, consisting of cells of the megakaryocyte-platelet and granulocytic series, including basophils, and erythroid precursors. This finding supported the view that TAM was the result of unstable hematopoiesis rather than true leukemia.
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PMID:Ultrastructural studies of peripheral blood of neonates with Down's syndrome and transient abnormal myelopoiesis. 296 57

The Kawakami-Theilen strain of feline leukemia virus (FeLV-KT), an exogenous anemia-inducing retrovirus, induced significant macrothrombocytosis and thrombocytopenia during acute infections of cats. The geometric mean platelet volumes of both freshly isolated fixed platelets and ethylenediamine tetraacetic acid-sphered platelets from infected cats were increased, but the ratio of fresh-fixed to ethylenediamine tetraacetic acid-sphered platelet volumes, an estimate of ethylenediamine tetraacetic acid-induced isovolumetric shape change, was normal. Total plasma membrane increased as the platelet volumes increased in FeLV-KT-infected cats, but estimated surface connected canalicular system surface area did not. Platelet concentrations were decreased 2 to 6 weeks after inoculation, but marked macrothrombocytosis resulted in a trend toward increased platelet mass on weeks 5 and 6 after inoculation. Thus, FeLV-KT-induced macrothrombocytosis may serve as a model of impaired platelet volume regulation. The platelet volume and platelet membrane surface area abnormalities found suggest that this model would allow studies of the megakaryocyte/platelet axis, particularly in the area of membrane formation and territorial demarcation.
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PMID:Feline leukemia virus-induced thrombocytopenia and macrothrombocytosis in cats. 300 2

Among nine cases of early erythroblastic leukemia previously diagnosed using a panel of antibodies, two patients have erythroid blasts expressing glycophorin A, seven patients have blasts with a more immature phenotype. These immature blasts were labeled by the FA6-152 monoclonal antibody when studied with the immunogold technique. The blasts exhibited large nucleoli, and their cytoplasm contained numerous ribosomes and large mitochondria. In the Golgi apparatus several granules resembled the theta granules as previously described and contained ferritin molecules in the absence of rhopheocytosis. A large proportion of these blasts exhibited a platelet peroxidase (PPO)-like activity. As the blasts from the two other patients with a more mature phenotype and glycophorin A reactivity lacked this PPO, this enzyme seems to be restricted to the more immature cells. Since in these leukemic samples immature erythroid blasts were admixed to promegakaryoblasts, immunogold labeling was also performed with antiplatelet antibodies. This latter population which was labeled with C17, a monoclonal antibody to platelet glycoprotein IIIa, showed strong PPO activity but lacked theta granules and ferritin. In the normal bone marrow enriched by panning for CFU-E (8%) and depleted in progenitors of other lineages, blast cells showing characteristics similar to leukemic erythroid blasts were seen. They exhibited theta granules and ferritin and a proportion of them also had a PPO-like activity. Thus, a PPO reaction is not restricted to the platelet-megakaryocyte line. In conclusion, a PPO-like activity and ferritin molecules were present in immature leukemic erythroid blasts. Similar cells could be identified from normal bone marrow.
Leukemia 1987 Mar
PMID:Ultrastructural and cytochemical characterization of blasts from early erythroblastic leukemias. 311 5

Ten cases in which leukemic cells contained numerous cytoplasmic granules were examined by using a panel of cytochemical reactions. The diagnoses in the 10 cases were mast cell leukemia, chronic basophilic leukemia, and acute myeloid leukemia with basophilic differentiation in one case each, acute promyelocytic leukemia in two cases, acute megakaryoblastic leukemia in two cases, and blastic hairy cell leukemia in three cases. The cytochemical panel consisted of peroxidase, toluidine blue, chloroacetate esterase, aminocaproate esterase, tartrate-resistant acid phosphatase, and immunoalkaline phosphatase for platelet/megakaryocyte-specific antigen. The unusual cytologic features of leukemic cells in cases similar to our 10 cases have caused considerable diagnostic difficulties. In our 10 cases, however, the effective use of cytochemical studies helped to achieve accurate identification of the various types of leukemic cells. We conclude that the intelligent application of cytochemical techniques continues to be useful for the accurate cytodiagnosis of hematopoietic neoplasms.
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PMID:Cytochemical characterization of leukemic cells with numerous cytoplasmic granules. 311 18

Primary polycythaemia (PP), idiopathic myelofibrosis (MF), essential thrombocythaemia (ET) and chronic granulocytic or myeloid leukaemia (CGL) are clonal disorders of the pluripotent haemopoietic stem cells. We have studied granulocyte, megakaryocyte and erythroid progenitors from the peripheral blood of 7 patients with PP, 9 with ET, 19 with MF and 6 with CGL in order to characterise similarities and differences at the committed progenitor cell level. Spontaneous megakaryocytic and erythrocytic growth was characteristic of MF, PP and ET but was not seen in CGL. Circulating erythroid (BFU-E) and granulocyte/macrophage (CFU-GM) progenitors were markedly increased in MF and CGL, less raised in ET and closest to normal in PP. Erythropoietin-independent erythroid bursts (EIBFU-E) grew from the blood of patients with MF, PP and ET but spontaneous growth of megakaryocytes occurred in only MF and ET. These results suggest a progression of increasing abnormality from PP, where EIBFU-E occurred with relatively normal numbers of circulating progenitors, to ET where both EIBFU-E and megakaryocyte precursors regularly occur with elevated numbers of progenitors, to MF where spontaneous BFU-E, CFU-Mk and CFU-GM occur at high levels.
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PMID:Primary polycythaemia, essential thrombocythaemia and myelofibrosis--three facets of a single disease process? 312 58

Ten leukemia and four aplastic anemia cases were clinicopathologically studied in autopsies from patients who had been administered the contrast medium, Thorotrast, three to five decades previously. The short period from the appearance of hematological symptoms to death, the relatively low percentage of leukemic cells in the peripheral blood, the high frequency of erythroleukemia, i.e., 50% of leukemia patients, and a case of atypical megakaryocyte proliferation were revealed in leukemia patients. Leukemic cell infiltration in the spleen tended to become slight or minimal with the progress of fibrosis. As a result, the degree of spleen swelling was mild or lacking in leukemia patients who had been administered Thorotrast. On the other hand, cases such as hyperplastic or normoplastic bone marrow, an increase in immature granulocytic series or no decrease in the number of megakaryocytes were observed in aplastic anemia of Thorotrast-administered patients. It was thought that fibrosis in the bone marrow as well as in the spleen was induced by Thorotrast deposition. Thus, in hematological disorders of Thorotrast-administered patients, both leukemia and aplastic anemia cases were considered to be mainly of the atypical type, and it was speculated that the damage due to Thorotrast may affect the hemopoietic stem cell level and hemopoietic microenvironment.
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PMID:Clinicopathological study of hematological disorders after Thorotrast administration in Japan. 316 98

In this report, we have described three cases of acute megakaryoblastic leukemia (AMKL) which were demonstrated by the presence of megakaryocyte-platelet-related cell-surface antigens detected by utilizing flow cytometry and monoclonal antibodies in addition to both PPO activity which was shown by ultrastructural cytochemistry and emergence of differentiation antigens while culturing these leukemic cells. The blasts of one case possessed both platelet GpIb and GpIIb/IIIa cell-surface antigens detected by 5F1 (CD36), AN51 (CDw42), and J15, P2 and HPL2 (CDw41), respectively, whereas the remaining two cases almost completely lacked Gp1b cell-surface antigen. Hence, the former was diagnosed as immature (pro) megakaryocytic leukemia and the latter as AMKL from the viewpoint of immunophenotypic analysis as discussed in this article.
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PMID:Flow cytometric analysis of peroxidase negative acute leukemias by monoclonal antibodies--II. Acute megakaryoblastic and acute pro-megakaryocytic leukemias. 316 41

Expression of major histocompatibility complex class II Ags HLA-DR, HLA-DP, and HLA-DQ on human BM granulocyte-erythroid-macrophage-megakaryocyte CFU (CFU-GEMM), BFU-E, and CFU-GM was examined by indirect immunofluorescence, cell sorting, and complement-mediated cytotoxicity. BM, highly enriched for progenitor cells by depletion of mature hematopoietic elements, was further separated by sterile sorting into HLA-DR (-), low, intermediate, and high intensity HLA-DR (+), as well as HLA-DP (+) and HLA-DP (-) cell fractions and assayed for progenitor cell content. In addition, in the case of HLA-DR, CFU-GM response to inhibition by prostaglandin E was determined. Cell sorting and cytotoxicity data confirm that approximately 95% of assayable erythroid, myeloid, and multipotential progenitor cells expressed HLA-DR, whereas HLA-DQ Ags were undetectable. HLA-DR and HLA-DP Ags were co-expressed on 61% of these progenitor cells, predominantly those expressing HLA-DR at high intensity. Day 7 and 14 CFU-GM showed a trend toward segregation to the high HLA-DR (+) cell fractions, especially when recombinant human G-CSF was used to stimulate clone formation. Both day 7 and day 14 CFU-GMs were found predominantly in the HLA-DP (+) cell fraction. In contrast, BFU-E and CFU-GEMM were found in the low intensity HLA-DR cell fraction and predominantly in the HLA-DP (-) fraction. Both eosinophil CFU and cells giving rise to basophil/mast cells in suspension culture were found in the low and intermediate intensity HLA-DR fractions, but could be segregated into HLA-DP (+) and HLA-DP (-) cell fractions, respectively. Functional analysis of day 7 CFU-GM segregated, based upon HLA-DR intensity, indicated a positive correlation between increasing HLA-DR intensity and responsiveness to inhibition by prostaglandin E. Furthermore, only those CFU-GM expressing HLA-DR at high intensity could be removed by cytolytic treatment using a mAb anti-HLA-DR previously shown to be selective for CFU-GM responsive to PGE and in S phase of the cell cycle.
Leukemia 1988 Oct
PMID:Differential expression of class II MHC antigens in subpopulations of human hematopoietic progenitor cells. 317 44

A new human megakaryocytic cell line (Dami) has been established from the blood of a patient with megakaryoblastic leukemia. The Dami cells grow primarily in suspension with a doubling time of 24 to 30 hours. By light and electron microscopy, the Dami cells range in size from 12 to 120 micron in diameter and have lobulated nuclei characteristic of megakaryocytes. At least 89% of the cells react with monoclonal antibodies against platelet glycoproteins (GP) Ib and IIB/IIIa, and glycophorin. The cells do not react with antibodies against lymphoid, monocyte, granulocyte, or macrophage antigens. Thirteen percent of the cells become polyploid, spontaneously achieving greater than 4N DNA ploidy levels. In response to phorbol myristate acetate (PMA), the proportion of cells with ploidy levels greater than 4N increased threefold and could be separated into discrete ploidy groups. PMA also increased the expression of GPIb, the GPIIb/GPIIIa complex,l and von Willebrand factor. Cytogenetic analysis revealed a human male hyperdiploid karyotype with a modal chromosome number of 54 to 64 and several consistent clonal chromosomal abnormalities. These included a partial deletion of chromosome 5 and a translocation involving chromosome 3. In contrast to other megakaryocytic cell lines in which only a small portion of the cells express the megakaryocytic phenotype, nearly all of the Dami cells express platelet glycoproteins. Thus, the Dami cells provide a superior model in which to study human megakaryocyte biochemistry and differentiation.
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PMID:Characterization of a new megakaryocytic cell line: the Dami cell. 319 74

A factor that stimulates the incorporation of 75Selenomethionine into the newly formed platelets of recipient mice (thrombopoietin, TPO) has been partially purified from the plasma of thrombocytopenic patients. The activity was precipitated at 60-80% ammonium sulfate saturation and further purified with hydrophobic interaction chromatography. Thrombopoietin was retained by concanavalin-A-Sepharose. Using HPLC size-exclusion chromatography, an approximate molecular weight of 40,000 dalton was calculated. The overall purification factor was about 2,100-fold. TPO was stable in a pH range from 5 to 9 and was heat-sensitive, and the biological activity was destroyed by trypsin treatment and by dithiothreitol. The partially purified molecule did not stimulate the proliferation of megakaryocyte progenitors in vitro and had no effect on the growth of erythroid or granulocyte-macrophage colonies; when administered in-vivo, TPO significantly affected the mean platelet volume and increased the number of small acetylcholinesterase cells in the bone marrow. TPO appears to be specific for the megakaryocytic lineage and active on the postmitotic compartment of megakaryocytes.
Leukemia 1988 Apr
PMID:Partial purification and biochemical characterization of human plasma thrombopoietin. 336 51


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