Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Biotinylated granulocyte/macrophage colony-stimulating factor (GM-CSF) analogues with different linkage chemistries and levels of conjugated biotin were synthesized by reacting recombinant human GM-CSF with sulfosuccinimidyl 6-biotinamidohexanoate or biotin hydrazide/1-[3-(dimethylamino)-propyl]-3-ethylcarbodiimide. These chemically reactive forms of biotin produced derivatives biotinylated at amine or carboxyl groups, respectively. Amine-derivatized analogues of 1.2 and 3.8 mol of biotin/mol of protein (N1-bGM-CSF and N4-bGM-CSF) and a carboxyl-modified analogue of 4.6 mol of biotin/mol of protein (C5-bGM-CSF) were synthesized. These analogues were compared to determine the effect of biotinylation on biological activity and GM-CSF receptor binding characteristics. The biotinylated proteins migrated with the same molecular weight as the native, unmodified protein as determined by SDS-PAGE and could be detected by Western blotting with alkaline phosphatase conjugated streptavidin, thus demonstrating the biotin linkage. All three analogues retained full agonist activity relative to the native protein (EC50 = 10-15 pM) when assayed for the stimulation of human bone marrow progenitor cell growth. Cell surface GM-CSF receptor binding was characterized by the binding of the analogues to human neutrophils, with detection by fluorescein-conjugated avidin and fluorescence-activated cell sorting. The N-bGM-CSFs demonstrated GM-CSF receptor specific binding that was displaceable by excess underivatized protein, with the detected fluorescence signal decreasing with increasing biotin to protein molar ratio. In contrast, C5-bGM-CSF binding above background fluorescence could not be detected using this system, suggesting that this derivative could bind to and activate the receptor, but not simultaneously bind fluorescein-conjugated avidin. The amine-derivatized biotinylated GM-CSF analogues retained biological activity, could specifically label cell surface receptors, and may be useful nonradioactive probes with which to study GM-CSF receptor cytochemistry and receptor modulation by flow cytometry.
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PMID:Biotinylated granulocyte/macrophage colony-stimulating factor analogues: effect of linkage chemistry on activity and binding. 183 6

This study examines the effect of leukemia inhibitory factor (LIF) on preosteoblastic rat calvaria (RCT-1) cells, which acquire osteoblastic properties when treated with retinoic acid (RA). LIF potentiated the increase in alkaline phosphatase (AP) activity produced by RA. The LIF effect was time and dose dependent (EC50, approximately 1 pM). The earliest effects on AP activity were detected at 48 h, and maximal effects were observed after 72 h. RA increased AP mRNA about 2-fold at 3 h and 6-fold at 6 and 12 h. LIF further increased AP mRNA to 18-fold at 12 h. After RA treatment AP mRNA returned to control levels at 24 h, but in the presence of LIF, AP mRNA remained elevated at 24 and 72 h of treatment. When given alone, LIF had no effect on either AP activity or mRNA levels. Tumor necrosis factor-alpha and 1,25-dihydroxyvitamin D3 also potentiated the RA induction of AP, and interleukin-6 had a small effect, whereas granulocyte macrophage colony-stimulating factor had no effect. LIF alone had a small inhibitory effect on type 1 collagen mRNA, but did not oppose the stimulatory effect of RA. Consistent with these biological actions, LIF receptors were demonstrated on these cells. [125I]LIF bound to RCT-1 cells at 0 C with an apparent dissociation constant of 20 pM, and it was found that these cells express an average of 300 receptors/cell. Scatchard analyses showed a single class of high affinity binding site. LIF was internalized with an endocytic rate constant for occupied receptors of 0.03 min-1, and the apparent equilibrium dissociation constant at 37 C was 358 pM. These findings suggest that osteoblast precursor cells are among the target cells of LIF.
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PMID:Leukemia inhibitory factor binds with high affinity to preosteoblastic RCT-1 cells and potentiates the retinoic acid induction of alkaline phosphatase. 211 91

The effects of recombinant cytokines on the ploidy of human megakaryocytes derived from megakaryocyte progenitors were studied using serum-free agar cultures. Nonadherent and T cell-depleted marrow cells were cultured for 14 days. Megakaryocyte colonies were identified in situ by the alkaline phosphatase anti-alkaline phosphatase technique, using monoclonal antibody against platelet IIb/IIIa. The ploidy of individual megakaryocytes in colonies was determined by microfluorometry with DAPI (4',6-diamidino-2-phenylindole) staining. Recombinant human interleukin 3 (rhIL-3) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) supported megakaryocyte colony formation in a dose-dependent manner. However, both rhIL-3 and rhGM-CSF had no definite ability to increase the ploidy values. Recombinant human erythropoietin (rhEpo) or recombinant human macrophage colony-stimulating factor (rhM-CSF) by itself did not stimulate the growth of megakaryocyte progenitors. rhEpo or rhM-CSF, however, stimulated increases in the number, size and ploidy values of megakaryocyte colonies in the presence of rhIL-3 or rhGM-CSF. Recombinant human interleukin 6 (rhIL-6) showed no capacity to generate or enhance megakaryocyte colony formation when added to the culture alone or in combination with rhIL-3. rhIL-6, however, increased the ploidy values in colonies when added with rhIL-3. These results show that rhEpo, rhM-CSF and rhIL-6 affect endomitosis and that two factors are required for megakaryocyte development.
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PMID:The effect of cytokines on the ploidy of megakaryocytes. 220 62

An adherent cell line, termed TC-1, has been isolated from long-term liquid culture of murine marrow cells by repeated exposure of the adherent cells to 0.1% trypsin. This is an alkaline phosphatase-positive cell line showing variable staining with acid phosphatase and alpha-naphthyl acetate esterase. On electron microscopy, the cells have moderate amounts of rough endoplasmic reticulum and variable numbers of polyribosomes. Some cells contain large clusters of laked glycogen particles. Intermediate junctions are present between some cells. Conditioned medium from this cell line produced from 384 to 638 units of CSF-1 per milliliter by radioimmunoassay and a CSF-1-dependent synergistic activity, which stimulates giant macrophage colony formation of marrow cells in soft agar. The conditioned medium also stimulates 3H-TdR incorporation by marrow cells in liquid culture and induces secondary adherent cell lines. The growth factor(s) produced by the TC-1 stromal cell line may be important in the regulation of early stages of hematopoietic differentiation. Two subclones, TC-1-C-11 and TC-1-C-3, have been isolated from passage 25 of the TC-1 cells by a penicylinder separation technique. The TC-1-C-11 is phenotypically like the parent TC-1 line and produces macrophage growth factors. The TC-1-C-3 grows as an epithelioid monolayer with visible junctions among adjacent cells under phase contrast microscopy. This subclone produces retrovirus and is capable of providing anchorage support for hematopoietic stem cells. The TC-1 cell line and its subclones may provide models for the control of early stem cell proliferation and differentiation.
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PMID:Hematopoietic factor production by a cell line (TC-1) derived from adherent murine marrow cells. 241 62

Recent studies have demonstrated by Northern blot analysis that both the c-fms proto-oncogene and the CSF-1 gene are expressed during human monocytic differentiation. In order to examine c-fms and CSF-1 expression at the cellular level, we have applied alkaline phosphatase detection of biotinylated v-fms and CSF-1 cDNA probes in situ. Using this approach, we demonstrate that c-fms and CSF-1 transcripts are detectable in HL 60 cells induced along the monocytic lineage but not in uninduced cells. The specific detection of these transcripts is further supported by the absence of histochemical staining in RNase-treated cells and when using pBR322 plasmid without insert as the biotinylated probe. Finally, the results indicate that most of the induced HL-60 cells have detectable levels of both c-fms and CSF-1 RNA. This approach should be useful for studying expression of these genes in populations of leukemic blasts and normal hematopoietic cells.
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PMID:Detection of c-fms and CSF-1 RNA by in situ hybridization. 244 33

The monocyte, monocyte conditioned media (MoCM), giant cell tumor conditioned media (GCT) and a purified colony-stimulating factor (G-CSF) promote granulocyte-macrophage progenitors (CFU-GM) growth and differentiation along the neutrophil lineage and also induce alkaline phosphatase (NAP) synthesis in the neutrophilic cells of normal subjects and of patients with chronic phase chronic myelogenous leukemia (CML). However, it is not known if granulocyte-macrophage-CSF (GM-CSF), macrophage-CSF (CSF-1) or other cytokines can induce NAP synthesis from the neutrophilic cells of CML patients. The objective of this study were (a) to ascertain which of the three CFU-GM CSFs would induce NAP synthesis, and (b) to test if any of the other cytokines--interleukin-1 (IL-1), interleukin-2 (IL-2), alpha- and gamma-interferons (alpha-INF and r-INF), and phytohemagglutinin-stimulated T-cell conditioned media (TCM) would induce NAP synthesis. Light density cells obtained from the blood of patients with chronic phase CML were depleted of T cells and monocytes. These cells were cultured with various amounts of G-CSF, GM-CSF, CSF-1, IL-1, IL-2, alpha-INF, r-INF, MoCM, GCT and TCM in a suspension culture system over 6-7 days. Evaluation of the cultures indicated that G-CSF, MoCM and GCT, but not the other factors or cytokines, consistently induced NAP synthesis in a dose-dependent manner. Actinomycin-D and puromycin in separate cultures inhibited NAP synthesis without any significant reduction in cell counts. This indicated that NAP is not prepackaged in neutrophilic cells, and its synthesis occurs by a sequential transcription at the DNA level and translation at the ribosomal level. Our results suggest that the molecule which is responsible for promotion of CFU-GM growth and differentiation along the neutrophilic cell lineage is also responsible for derepression of NAP gene and initiation of NAP synthesis.
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PMID:Granulocyte colony-stimulating factor (G-CSF) induces synthesis of alkaline phosphatase in neutrophilic granulocytes of chronic myelogenous leukemia patients. 245 37

We have previously reported that the J774A.1 macrophage-like tumor cell line produces two potent monokines which stimulate the growth of osteoblasts and chondrocytes. These growth factors, which have an affinity for heparin-agarose, have been termed HEP I (a 30 Kd PDGF-like molecule) and HEP II (an approximately 20 Kd molecule), respectively, based on their elution profile. Unlike HEP I, HEP II does not stimulate the growth of fibroblasts. Extensive biological and chromatographic studies disclosed that HEP II appears to be a unique bone cell mitogen unlike any known growth factor, including the FGFs, IL-1s, and TNFs, EGF, IGF-I and -II, TGF-beta, beta 2 microglobulin, G-CSF, CSF-1 and GM-CSF. To characterize more fully the effects of the macrophage-derived monokines on osteoblast growth and function, clones were derived from calvaria explant cultures. Two clones, SDFRC-2.05 and SDFRC-3, were developed and found to exhibit osteoblastic characteristics, including high levels of alkaline phosphatase, synthesis of type I but not type III collagen, and an increased intracellular cAMP production in response to PTH. The SDFRC-3 cells exhibited a polygonal morphology like that of the explant-derived cells while SDFRC-2.05 cells exhibited a more fibroblastic morphology. When tested on the explant cultures and clones, HEP I and HEP II were found to stimulate DNA synthesis and increase protein per culture, but decreased alkaline phosphatase activity. Clone SDFRC-3 was found to be more responsive to HEP II than clone SDFRC-2.05. Both monokines were found to be more potent mitogens for bone cells than TGF-beta. HEP II, but not HEP I or TGF-beta, induced a transformation of bone cells from a polygonal to a fibroblastic morphology, suggesting the induction of migration prior to proliferation. Thus, macrophages may be responsible not only for bone repair but also for ensuring the linkage of bone formation to resorption during physiological remodeling.
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PMID:Monokines produced by macrophages stimulate the growth of osteoblasts. 263 Jan 69

Studies on blood serum from mammary carcinoma (MC) hosts, which promoted gamma-glutamyl transpeptidase (GGT) expression by normal rat bone marrow cells in liquid culture, were extended to various granulocyte-macrophage colony stimulating factors (CSFs). GGT concentration per cell was found to increase (without change in total cell number) by incubation for 48 h with purified CSF-2 gamma and CSF-1 (but not interleukin-3), with human giant cell elaborated GM-CSF and L-cell conditioned medium, as well as with the 3 MC preparations (host serum, MC extract and MC conditioned medium). GGT-inducing ability (per milligram protein) ranked the 7 preparations in the same order as did their proliferative effect (number of colonies per milligram protein) in the standard mouse bone marrow agar culture system. The quantitative correlation between these two kinds of activities (linear for their logarithmic values) was highly significant, r = 0.976, p less than 0.001. The alkaline phosphatase concentration of bone marrow cells in liquid culture was also increased in the presence of the same 7 preparations, and this again was proportional (r = 0.985, p less than 0.001) to their colony stimulating potential.
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PMID:Enhancement of gamma-glutamyl transpeptidase expression in bone marrow cells by colony stimulating factors. 290 68

These data suggest that two types of radioresistant adherent stromal cells are adequate for maintenance of long term hemopoiesis in the Dexter culture system. One cell type appears to be a typical adherent macrophage while the other is an alkaline phosphatase positive epitheloid cell possibly representative of the adventitial reticular cell of the bone marrow. These two cell types seem to be clearly defined by the in-vivo irradiation studies and less clearly defined in the in-vitro irradiation experiments. These data do not exclude other cell types as playing important roles in modulating hemopoiesis but do suggest that these major types are probably playing important roles in maintaining stem cells in long term liquid cultures. In addition, data suggests that the epitheloid cell directly nurtures hemopoietic cells on its surface while the macrophages may serve a separate function. A number of growth factors are produced by these two cell types which appear to include CSF-1, a granulocyte CSA separate from CSF-1 and a megakaryocyte CSA separate from both the GM-CSA and CSF-1 (Table 5). Thus the present data suggest that there are at least three (formula; see text) separate hemopoietic growth factors produced. The FDC-P1 activity produced by irradiated stroma would appear most likely to be GM-CSA-II. The fact that lectins enhanced production of these activities is intriguing but the cell type on which the lectins are acting has not as yet been defined. It appears that lithium also acts upon adherent marrow stromal cells to induce production of myeloid regulatory growth factors. Lithium appears to stimulate both normal and irradiated stroma to produce hemopoietic maintenance and growth factors and the present data suggests that factors active on pre IL-3 cells, HPP-CFC, CFU-D, CFU-meg, and CFU-S are all induced from these stromal cells by lithium. Whether the lithium induced factors and the factors derived from irradiated stroma represent a number of different growth factors or one or two critical regulatory molecules is at present unclear. The synergistic activity derived from the TC-1 cell line is of particular interest in this regard. This CSF-1 dependent activity is capable of acting on a very primitive stem cell to induce impressive proliferation and differentiation. In addition an activity in TC-1 conditioned media which may be synergistic activity appears capable of inducing adherent marrow cell lines which then can subsequently produce more of the same factor, a classic autocrine system.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Bone marrow adherent cell hemopoietic growth factor production. 393 Oct 91

We established a human bone marrow stromal cell line (Saka) by infecting marrow adherent cells from semisolid marrow cultures with a recombinant simian virus-40 (SV40) virus. The cells expressed SV40 large tumor antigen, had a fibroblast-like shape, and expressed fibronectin and vimentin. They did not contain detectable alkaline phosphatase activity; express myeloid, lymphoid, or factor VIII-associated antigens; or develop adipocyte-like characteristics with dexamethasone treatment. Polymerase chain reaction analysis of Saka cell RNA detected expression of messenger RNAs for interleukin-6 (IL-6), IL-1 beta, granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor, stem cell factor, and the 1,25-dihydroxyvitamin D3 receptor. Coculture of Saka cells with human marrow mononuclear cells enhanced formation of osteoclast-like multinucleated cells (MNC) in long term human bone marrow cultures. These MNC expressed calcitonin receptors and formed resorption lacunae on dentine. In contrast, coculture of marrow mononuclear cells with other SV40-transformed human marrow stromal cell lines did not increase MNC formation. Conditioned medium from Saka cells or coculture of bone marrow and Saka cells separated by a Millipore membrane did not enhance MNC formation. Addition of a neutralizing antibody to IL-6 or IL-1 beta blocked the effects of Saka cells on MNC formation. These results suggest that marrow stromal cells enhance osteoclast formation in part through direct cell to cell contact and production of IL-6 and/or IL-1 beta.
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PMID:Development and characterization of a human marrow stromal cell line that enhances osteoclast-like cell formation. 753 99


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