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)

Leukemia-growth-promoting factor (LGPF) as we previously reported stimulates the growth of a murine leukemia subline (L17R) extensively. LGPF was isolated and 10(4) fold purified from calf thymuses by a combination of ammonium sulfate precipitation, Sephadex G-100 chromatography, hydroxylapatite chromatography, and Mono S-fast protein liquid chromatography (Mono S-FPLC). The mol. wt of LGPF was estimated to be approximately 25,000 a.m.u. from the elution pattern of Sephadex G-100 chromatography. The activity had high affinity for Mono S beads which are cation exchangers. Mono S fractions of LGPF are effective at a low concentration of 5 ng/ml. The activity was inactivated by heat (56 degrees C, 30 min), 1 mg/ml trypsin (37 degrees C, 1h), and 50 mM dithiothreitol (20 degrees C, 1h). The growth L17R leukemia cells are not only stimulated by LGPF, but also by pituitary and brain fibroblast growth factor (FGF). These data strongly suggest that LGPF is a heat sensitive cationic protein(s) acting as a member of FGF family.
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PMID:Isolation and characteristics of a leukemia-growth-promoting factor from calf thymus. 386 13

A 3-hour-old phenotypically normal girl was transferred to Children's Hospital Medical Center because of skin nodules, hepatosplenomegaly, and marked leukocytosis. The predominant cells in the blood, bone marrow, and dermis were monoblasts consistent with congenital leukemia. Known causes of leukemoid reactions were excluded. The infant received two double-volume exchange transfusions but no chemotherapy. As the white blood cell counts decreased, the monocytic cells became more mature, suggesting that the monoblasts had the ability to differentiate. The proliferative capacity of the marrow appeared to be normal as determined by the ability of marrow cells to form colonies in soft agar. Chromosomal analysis of bone marrow blasts including trypsin--Giemsa banding was normal. Three weeks after birth the patient's CBC and physical examination were normal, and the bone marrow was normal by 4 months of age. The patient has remained in remission for over 3 years.
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PMID:Spontaneous remission of presumed congenital acute nonlymphoblastic leukemia (ANLL) in a karyotypically normal neonate. 386 95

Fibronectin was detected by immunofluorescence on the surface of one fraction of separated normal peripheral blood lymphocytes using FITC-conjugated anti-human fibronectin antibodies. Approximately one fifth of isolated B cells and 7% of O cells contained surface bound fibronectin but T cells failed to stain. There were no detectable free receptors for fibronectin on the surfaces of the lymphocytes in the different subsets isolated from healthy controls as studied using FITC-labelled purified fibronectin. The per cent of B and O cells bearing surface bound fibronectin was markedly decreased in patients with acute and chronic lymphocytic leukemias and non Hodgkin's lymphoma, only 1-4% of B and 1-2% of O cells stained with FITC-labelled antifibronectin immunoglobulins. FITC-conjugated fibronectin was not bound to the different lymphoblasts isolated from patients with leukemia and lymphoma. Treatment of cells with trypsin and EDTA removed fibronectin bound to the cell surfaces. Fibronectin attached to the surfaces of lymphocytes may have an immunoregulatory function.
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PMID:Cell surface fibronectin on peripheral blood lymphocytes in normal individuals and in patients with acute and chronic lymphocytic leukemia and non Hodgkin's lymphoma. 389 Apr 99

To examine the plasma membrane characteristics of an immature monocytic cell capable of proliferation, we have developed a murine monoclonal antibody that identifies an antigen, Mb1, found on the surface of U-937. In immunofluorescence analyses, Mb1 is not expressed by peripheral blood monocytes (freshly isolated, lymphokine-activated, or cultured for seven days), neutrophils, or any other circulating element. It is also absent on human bone marrow mononuclear cells, including the CFU-GM. Among a series of malignant cells from 50 patients with acute myeloid leukemia (including 22 with monocytic or myelomonocytic leukemia), no Mb1 expression was detected. Continuous human cell lines of B or T cell origin were also negative, as were the myeloid lines HL-60 and K562. Apart from U-937, which uniformly expresses Mb1 in high antigen density, only KG-1 (a myeloblastic line) exhibits Mb1 in low antigen density. Exposure of U-937 to phorbol diester (TPA) under conditions that induce features of macrophage differentiation (including the expression of Mo1) results in a significant reduction in Mb1 expression. Mb1 expression is also reduced as a result of culture of U-937 in medium containing anti-Mb1 antibody (antigenic modulation). On sodium dodecyl sulfate-polyacrylamide gel electrophoresis of radiolabeled immunoprecipitates, Mb1 appears to be a dimeric protein with an estimated molecular weight of 80 kd (43 kd under reducing conditions). Antigenic activity on U-937 is destroyed by treatment with trypsin or papain but is regenerated after 24 hours' culture in enzyme-free medium. Mb1 is a constituent plasma membrane protein of U-937, and its degree of expression relates to the state of cellular differentiation.
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PMID:Mb1, a plasma membrane antigen selectively expressed by U-937 cells. 389 Sep 83

Glycopeptides containing individual N-glycosylation sites of the glycoprotein from Friend murine leukemia virus were isolated by digestion of the viral glycoprotein with protease of S. aureus (V8) or with trypsin followed by fractionation of the resulting (glyco)peptides by gel filtration and reversed-phase, high-performance liquid chromatography at pH 6. Isolated glycopeptides were assigned to the known amino acid sequence of the protein by amino acid analysis and by determination of the NH2-termini. The carbohydrate moieties of each glycosylation site were analysed by methylation analysis. A high selectivity of the glycoprotein glycosylation was found with regard to the distribution of oligomannosidic, mixed, and N-acetyl-lactosaminic oligosaccharides.
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PMID:Isolation of glycopeptides containing individual glycosylation sites of Friend murine leukemia virus glycoprotein: studies of glycosylation by methylation analysis. 389 87

The nature of serum factors which participate in the interaction in vitro between dimethylsulphoxide-induced Friend leukaemia erythroblasts (IFLE) and syngeneic mouse peritoneal macrophages was investigated. When heat-inactivated newborn calf serum (HI-NBCS) was depleted of IgG its activity to promote the association of neuraminidase-treated 59Fe-labelled IFLE (59Fe-IFLE) with macrophages was markedly reduced but could be restored by the addition of bovine IgG. Trypsin treatment of macrophages caused incomplete inhibition of their subsequent association with both untreated and neuraminidase-treated 59Fe-IFLE in the presence of HI-NBCS. When spectrin, the major red cell cytoskeleton protein, was added to HI-NBCS there was a dose-related inhibition of the association with macrophages of both untreated and neuraminidase-treated 59Fe-IFLE. Moreover a mouse monoclonal antibody against spectrin promoted the interaction of neuraminidase-treated 59Fe-IFLE with macrophages. Mouse sera which supported the association of neuraminidase-treated 59Fe-IFLE with macrophages were found to contain anti-spectrin antibodies. These results suggest that IgG antibodies mediate the interaction between erythroblasts and macrophages via trypsin-sensitive and trypsin-resistant receptors on the macrophage surface and that at least some of the antibodies show specificity for spectrin.
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PMID:A possible role for antibodies against spectrin in the interaction between erythroblasts and macrophages in vitro. 397 Aug 28

We report here new characteristics of cell surface tubulin from a human leukemia cell line. These cells (CEM cells) possess tubulin that is readily iodinated on the surface of living cells, turns over at a rate identical to that of other surface proteins, and is present throughout the cell cycle. When removed with trypsin, it rapidly returns to the surface. Peptide mapping of iodinated surface tubulin indicates that it possesses a similar, but not identical, primary structure to total CEM and rat brain tubulin. Living CEM cells are able to bind specifically a subfraction of CEM tubulin from metabolically labeled high speed supernatants of lysed CEM cells. Surface tubulin is more basic than the total tubulin pool. The binding, which is saturable, is inhibited by unlabeled CEM high speed supernatants but not by excess thrice-cycled rat or bovine brain tubulin. Surface tubulin is also shown to bind to living nontransformed normal rat kidney cells but not to normal, circulating, mononuclear white cells. Activated lymphocytes produce a tubulin that binds to CEM cells. Since CEM tubulin was detected in the media of 6-h cultures of CEM cells, we must conclude that at least some of the surface tubulin comes from the media. We further conclude that these leukemic cells produce an unusual tubulin that may bind specifically to any membrane. The presence of iodinatable surface tubulin, however, appears to require both the production of a unique tubulin and the presence of a "receptor-like" surface binding component.
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PMID:Cell surface tubulin in leukemic cells: molecular structure, surface binding, turnover, cell cycle expression, and origin. 406 62

Australia antigen [Au(1)], a particle associated with viral hepatitis, was isolated from the plasma of a patient with chronic anicteric hepatitis and leukemia who had received radioactive phosphorus. We have found that the immunoreactivity and appearance of Au(1) in the electron microscope were not altered by treatment with enzymes including trypsin, pronase, lipase, phospholipase C, ribonuclease, deoxyribonuclease, amylase, and neuraminidase. In contrast, other serum constituents were degraded by these enzymes. Therefore, treatment of the patient's plasma with many enzymes was exploited as an initial step for the isolation of Au(1). Subsequently, Au(1) was purified from the enzyme-treated (32)P-labeled plasma by gel filtration through Sephadex G-200 and centrifugation through sucrose and in cesium chloride gradients. There were no detectable human serum components in the purest fractions, as tested by immunoelectrophoresis and immunodiffusion. The density of the purified Au(1) was 1.21 in CsCl. The particle measured about 200 A in diameter, was predominantly spherical in shape and appeared to be composed of subunits. Nucleic acids were not detected by spectrophotometric, radiochemical, and chemical analyses. Immunoreactivity of purified Au(1) was destroyed by heating for 1 hr at 85 degrees C but was stable at 56 degrees C. Treatment with Carnoy's solution (3 parts ethanol:1 part glacial acetic acid) followed by pronase disrupted the particles as seen with the electron microscope. These findings, combined with other published information on Australia antigen and viral hepatitis, suggest that the bulk of Australia antigen in the blood of this patient is an incomplete virus or virus capsid.
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PMID:Australia antigen (a hepatitis-associated antigen): purification and physical properties. 424 40

Primate antiserums to human leukemia cells can detect antigens specific for lymphocytic leukemia cells or antigens present on certain myeloid leukemia cells. The antigen specific for lymphocytic leukemia cells is destroyed by treatment with neuraminidase or trypsin. Tryptic digests of lymphocytic leukemia cells contain the antigen, which has a high molecular weight.
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PMID:Antigens specific for human lymphocytic and myeloid leukemia cells: detection by nonhuman primate antiserums. 462 23

Peritoneal exudate cells (PEC), obtained after the rejection of EL4 leukemia by BALB/c mice, are much more effective in the specific in vitro destruction of (51)Cr-labeled EL4 cells than are spleen, thymus, lymph node, or peripheral blood lymphocytes. The presence of a large number of effector cells at the site of graft rejection is reflected in the potent cytolytic activity seen in vitro. Effector cells temporarily lose cytolytic reactivity when treated with trypsin but regain reactivity with time. This recovery occurs in normal as well as in immune serum. The destructive reactivity of PEC is increased when macrophages are removed. The remaining population of nonadherent PEC is composed primarily of small- to medium-sized lymphocytes. Complex tissue culture media are not needed, but there is a definite requirement for serum. The required serum component is heat stable, nondialyzable, and is not consumed during the reaction. The use of an ascites allograft system made these observations possible and permitted the isolation of those host cells intimately associated with rejection.
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PMID:Rejection of ascites tumor allografts. I. Isolation, characterization, and in vitro reactivity of peritoneal lymphoid effector cells from BALB-c mice immune to EL4 leukosis. 502 38


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