Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Concanavalin A (Con A), wheat germ agglutinin (WGA), and Ricinus communis agglutinin (RCA) bound with either 125I, fluorescent dyes, or fluorescent polymeric microspheres were used to quantitate and visualize the distribution of lectin binding sites on mouse neuroblastoma cells. As viewed by fluorescent light and scanning electron microscopy, over 10(7) binding sites for Con A, WGA, and RCA appeared to be distributed randomly over the surface of differentiated and undifferentiated cells. An energy-dependent redistribution of labeled sites into a central spot occurred when the cells were labeled with a saturating dose of fluorescent lectin and maintained at 37 degrees C for 60 min. Reversible labeling using appropriate saccharide inhibitors indicated that the labeled sites had undergone endocytosis by the cell. A difference in the mode of redistribution of WGA or RCA and Con A binding sites was observed in double labeling experiments. When less than 10% of the WGA or RCA lectin binding sites were labeled, only these labeled sites appeared to be removed from the cell surface. In contrast, when less than 10% of the Con A sites were labeled, both labeled and unlabeled Con A binding sites were removed from the cell surface. Cytochalasin B uncoupled the coordinate redistribution of labeled and unlabeled Con A sites, suggesting the involvement of microfilaments. Finally, double labeling experiments employing fluorescein-tagged Con A and rhodamine-tagged WGA indicate that most Con A and WGA binding sites reside on different membrane components and redistribute independenty of each other.
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PMID:Differences in the redistribution of concanavalin A and wheat germ agglutinin binding sites on mouse neuroblastoma cells. 43 95

Changes in carbohydrate composition of the cell surface related to neuronal maturation have been studied on neuroblastoma and embryonic dorsal root ganglia (DRG) cultures by using fluorescein conjugated lectins. In neuroblastoma cells, it has been found that the surface of the fibers differs from that of the cell body as shown by concanavalin A (Con A) and WGA binding. In primary cultures of embryonic DRG, lectin binding has also shown that the neuron surface undergoes changes during maturation. In fact, lectin binding which is absent at early stages (5--6 day old embryos) becomes first detectable at the 7th day and then increases progressively. At day 7, the Con A binding pattern resembles that observed in neuroblastoma cells. The possibility of correlating these surface changes with cell adhesive properties and cell differentiation is discussed.
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PMID:Cell surface modifications in neuronal maturation. 69 52

In order to investigate a possible role of lectin activity of ricin in its absorption from the small intestine, we prepared two ricin derivatives. BMH-ricin, prepared by crosslinking A and B chains of ricin with 1,6-bismaleimidohexane, was nearly non-toxic but the lectin activity was unaltered. And, NBS-ricin, prepared by the oxidation of tryptophanyl residues of ricin with N-bromosuccinimide, was not only non-toxic but also non-lectinic. After the oral administration of ricin derivatives to rats, their interaction with the digestive tract and absorption into the circulatory systems have been compared with those of ricin, immunochemically and histologically. It was shown by immunostaining that ricin and BMH-ricin could bind to the intestinal mucosa, whereas NBS-ricin could not. No appreciable damage in the small intestine from rats treated with either BMH-ricin or NBS-ricin has been observed, in contrast to ricin treatment where severe impairment of the small intestinal tissues resulted after 5 h. Immunoreactive ricin in the liver has been determined with the ricin enzyme immunoassay (EIA). When compared at 48 h after oral administration, NBS-ricin was not detected, whereas BMH-ricin was found to be 38 micrograms/liver and ricin 100 micrograms/liver. From these results, it was inferred that the lectin activity of ricin plays an important role in the absorption of ricin from the small intestine and that the absorption of ricin protein was enhanced by its high toxicity.
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PMID:Biochemical studies on oral toxicity of ricin. V. The role of lectin activity in the intestinal absorption of ricin. 139 37

We have previously reported the isolation of a 66 kDa melanoma-associated antigen, identified by autologous antibody, in serum and unfractionated spent tissue culture media by Western blot analysis. The antigen, detected by autologous serum S150, was found to be broadly represented on melanoma, glioma, renal cell carcinoma, neuroblastoma and head and neck carcinoma cell lines. S150 did not react with bladder or colon carcinoma, fetal fibroblasts, pooled platelets, lymphocytes and red blood cells, autologous cultured lymphocytes or fetal calf serum. To further characterize the antigen, spent tissue culture media, obtained from autologous melanoma cell line, Y-Mel 84:420, was separated by an isoelectric focusing column. Unabsorbed control serum S150 was noted to have a maximum titer of 1:2040 against autologous melanoma cells as measured by protein A hemadsorption. Following isoelectric focusing the greatest decrease in autologous antibody titer (30-fold) occurred with fractions having a pI between 2 and 3. Further resolution of the antigen was accomplished with high-pressure ion-exchange chromatography. One of these fractions showed a significantly higher concentration of antigen and was distinctly resolved from bulk serum albumin. Subsequent Western blot analysis, with autologous antibody, of the isolated antigen-containing fraction, confirmed the presence of a single 66 kDa band. Exposure of the antigen, purified by high-pressure ion-exchange chromatography, to neuraminidase ablated recognition by autologous antibody and suggests that sialic acid is present on the protein and may be part of the antigenic epitope. Binding of antigen, obtained following DEAE anion exchange chromatography, was noted to lectins derived from Triticum vulgaris, Dolichos biflorus and Lycopersicon esculentum. Preparative purification of the antigen was accomplished by anion exchange followed by lectin affinity chromatography with a Dolichos biflorus column. Antigen obtained following lectin affinity chromatography subjected to SDS-PAGE and silver stain revealed a single band at 66 kDa. We conclude that a melanoma-associated antigen detected by autologous antibody in spent tissue culture media is an unusually acidic glycoprotein (pI 2-3).
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PMID:Purification and partial characterization of a shed 66 kDa melanoma-associated antigen identified by autologous antibody. 193 77

Human neuroblastoma SK-N-SH-SY5Y (SY5Y) and rat pheochromocytoma PC12 cells are model cell lines used in the study of nerve growth factor (NGF) effect. The effects of NGF are initiated by binding to cell surface receptors (NGFR). The amino acid sequence for NGFR has been deduced based on the identification of a single gene for NGFR. However, there are two kinds of NGF binding activities and several reported molecular weights of NGFR. We report here on the demonstration of NGFR-like proteins from PC12 and SY5Y cells by sequential lectin chromatography, reverse-phase HPLC, and SDS-PAGE analysis of immunoprecipitates obtained with NGFR-specific monoclonal antibodies. For both human and rodent NGFR, there was a tendency for the higher molecular-weight species of NGFR-like proteins to be eluted in more hydrophobic fractions. Also, the expression of different species of NGFR could be modified by treatment with retinoic acid (RA). These results are consistent with the hypothesis that the different molecular species of NGFR may result from the generation of a truncated form of NGFR, the presence of sugar residues on the NGFR protein, dimer formation between NGFR, or the association of NGFR with a receptor-associated protein.
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PMID:Reverse-phase high-performance liquid chromatography of nerve growth factor receptor-like proteins identified with monoclonal antibodies. 196 79

A method is described for quantitative measurements of homotypic aggregation by sequential passaging of cells through several gauze nets with different mesh width. This method allows rapid and simple determination of the size distribution of the formed aggregates with little cost. Time course and the effects of divalent cations, sugars and of enzyme treatment on homotypic aggregation were examined in detail for the human colon carcinoma line HT29, but also aggregation of human neuroblastoma, leukemic promyelocytes HL60, and of murine lymphoma cells was studied. Crude membrane fractions prepared from several colon carcinoma cells and from dissociated human colon tumour tissue showed strong aggregation-promoting effects when incubated with HT29 cells. Determination of lectin-induced agglutination of HT29 cells by means of the proposed method demonstrated that HT29 carries high numbers of binding sites for Ricinus communis agglutinin, wheat germ agglutinin, Ulex europeus agglutinin and Griffonia simplicifolia I isolectin A4. These results were supported by direct microanalytical determination of membrane-bound sialic acid and total fucose.
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PMID:A new test to measure homotypic aggregation of human tumour cells. 230 63

Peculiarities of the binding of lectins of castor bean, cochlea, soya bean, lime bean and wheat germs to the surface of differential neuroblastoma C 1300 N 18 cells have been studied using the method electron cytochemistry. It is found that the quantity of the bound lectin conjugates with colloidal gold on the surface of differentiated cells varied considerably from that on the surface of nondifferentiated cells.
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PMID:[The characteristics of lectin binding to the surface of differentiated neuroblastoma C 1300 cells]. 231 32

Normal human bone marrow cells were mixed with neuroblastoma cells from four different human cell lines, and the cell mixtures were separated by differential agglutination with soybean agglutinin (SBA). The unagglutinated cell fraction, previously shown to be highly enriched for the hematopoietic pluripotential stem cells and capable of reconstituting lethally irradiated adult patients with acute leukemia, was further fractionated by affinity chromatography on the lectin conjugated to Sepharose 6MB beads. Two independent assays, one using radiolabeling of the tumor cells and the other based on cloning of the neuroblastoma cells on agar, showed that the agglutination step alone removes 64-76% of the radiolabeled neuroblastoma cells and 85-98% of the clonogenic cells from the tumor/bone marrow cell mixture. Passage of the unagglutinated radiolabeled cells through SBA-Sepharose columns results in further purging of 28-53% of the neuroblastoma cells. Thus a combination of the two methods affords only one-log depletion for the neuroblastoma cells, compared to a three-log depletion achieved for a T-cell leukemia line CEM tested in parallel. It seems therefore that the agglutination technique, or the use of SBA-Sepharose columns, can be used only as a preliminary step for the purging of neuroblastoma cells from involved human bone marrow preparations. Staining with fluorescein isothiocyanate-conjugated SBA of nine different neuroblastoma cell lines, including the four tested in the fractionation studies, showed that more than 98% of the cells, of all the cell lines tested, specifically bind to the lectin, whereas no specific binding can be detected on the stem cell-enriched bone marrow cell fraction. However, the total number of receptors on the neuroblastoma cells is small compared to that of line CEM or normal granulocytes, which are strongly agglutinated by SBA. It seems therefore that the quantitative difference in the total number of SBA receptors is a crucial factor for purging by the agglutination technique or by affinity chromatography. Although these results show limitations to the use of both methods, this study establishes that all neuroblastoma cell lines tested express receptors for the lectin. Improved purging of neuroblastoma cells may possibly be achieved by targeting SBA-bound toxins or magnetic spheres to these receptors.
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PMID:Differential binding of soybean agglutinin to human neuroblastoma cell lines: potential application to autologous bone marrow transplantation. 241 94

The cytochemical properties of intracellular membrane systems which are likely to be subcellular sites of glycoprotein oligosaccharide synthesis and trafficking have been compared in cultured neuroblastoma cells (as a potential model system) and in Purkinje neurons of rat cerebellum. In aldehyde-fixed N18 cells, permeabilized with Triton X-100, concanavalin A (Con A) binding sites were found in the somata, neurites, and growth cones. Con A binding sites in growth cones appeared as a fine, membranous network. Wheat germ agglutinin (WGA) binding sites were restricted to the perinuclear region of the soma and to the distal tips of growing neurites. As shown previously, Purkinje cell somata and presynaptic terminals also contain Con A binding sites. In this study, WGA and succinylated WGA binding sites were observed in the presynaptic terminals of Purkinje cells. Neuraminidase enzyme digestion prior to lectin labeling removed or greatly reduced WGA binding in the neuropil of the deep nucleus but not in presynaptic terminals of Purkinje cells. Succinylated WGA binding sites were not affected by neuraminidase digestion. Neuraminidase digestion also exposed Ricinis communis agglutinin I binding sites in the neuropil and in synaptic terminals of Purkinje cells. These results in combination with previous studies of intracellular lectin cytochemistry of neurons in the central nervous system demonstrate the similarity of these cells to neuroblastoma cells in their intracellular lectin binding characteristics. Results of the lectin cytochemical studies after neuraminidase digestion of presynaptic terminals support the possibility that neurons may use a post- or extra-Golgi system for the addition of peripheral sugars to the oligosaccharides of certain glycoproteins destined for the cell surface.
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PMID:A comparative study of the intracellular lectin binding sites of neurons in culture with neurons in situ. 241 90

The activity of neurotoxin-responsive Na+ channels in mouse neuroblastoma cells, N-18, was examined after treating the cells with compounds that are reported to perturb intracellular traffic. The compounds used have been shown to either alter glycoprotein synthesis and processing, (swainsonine, castanospermine, monensin, and retinoic acid) or receptor mediated endocytosis (mevinolin, 7-ketocholesterol, and chloroquine), or both. All of these compounds inhibited the activity of the neurotoxin-responsive Na+ channel with the exception of retinoic acid which increased the activity. Na+ channel activity was measured by two methods: (a) In vivo, the efflux of 86Rb was measured by use of the cells in monolayer culture, and (b) in vitro, the flux of 86Rb was measured from artificial phospholipid vesicles containing the partially purified Na+ channel. In both cases, 86Rb flux responded to stimulating neurotoxins, veratridine and scorpion venom, and was inhibited by tetrodotoxin as characteristic of excitable membranes. One of the perturbing compounds, swainsonine, was examined in detail. Treatment of N-18 cells with 10 microM swainsonine for 24 h markedly reduced the activity of the neurotoxin-responsive Na+ channel, as shown by the neurotoxin-stimulated efflux of 86Rb in vivo. In addition, after reconstitution into phospholipid vesicles of the partially purified Na+ channel from swainsonine-treated cells, reduced 86Rb flux was observed when compared with that of nontreated cells. Furthermore, the activity was not recovered in other less purified fractions. A comparison of the glycopeptides from the treated and nontreated cells by size, charge, and lectin-binding affinities was consistent with the formation of hybrid oligosaccharides after swainsonine treatment. It is concluded that the oligosaccharide residues of the Na+ channel glycoprotein must be processed to the mature complex-type for full activity. The stimulation of channel activity by treatment with retinoic acid supported this conclusion.
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PMID:Perturbation of glycoprotein processing affects the neurotoxin-responsive Na+ channel in neuroblastoma cells. 242 66


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