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)

A membrane glycoprotein, Mr = 20,000, has been purified from human neuroblastoma cells (IMR-5) with the use of monoclonal antibody selected for binding capacity to human neuroblastoma cell lines. The antigen was extracted with 0.5% Nonidet P-40 from cells metabolically labeled with L-[3H]fucose or D-[3H]glucosamine. A double antibody affinity column was used to purify the membrane glycoprotein. Goat anti-mouse IgM was coupled to cyanogen bromide-activated Sepharose 4B. The absorption of the monoclonal antibody contained in ascites fluid completed the affinity column. Appropriate controls of similar material from other cell types and another monoclonal antibody demonstrated the specificity of the affinity column. Glycopeptides from the surface of human neuroblastoma cells, IMR-5 and CHP-134, had antigenic activity, as radioactive pronase-digested material bound to the affinity column and inhibited complement-mediated cytolysis. Glycolipids extracted from the cells had no antigenic activity. It was concluded that the carbohydrate residues of the glycoprotein conferred the antigenic specificity. Three methods were devised to aid in detection and purification of the antigen. These were: 1) an assay for the detection of complement-mediated cytolysis by measuring the enzyme creatine phosphokinase in the nonlysed target cells; 2) precipitation of the antigen . antibody complex with 4% polyethylene glycol; and 3) removal of the antibody by a wheat germ agglutinin-agarose column.
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PMID:A membrane glycoprotein from human neuroblastoma cells isolated with the use of a monoclonal antibody. 616 Jan 55

Immunoprecipitation studies with application of monoclonal antibody F11 originally made to a partially purified spent medium antigen of melanoma cells, made it possible to delineate the molecular profiles of both the cell associated and spent medium antigens recognized on melanoma cells intrinsically labeled with glycoprotein precursors. F11 distinguishes a glycoprotein of Mr 100,000 (100 K) in the spent media of melanoma cells while a parallel analysis of detergent lysates of cells reveals a pattern of three glycoproteins of Mr 75, 77, and 100 K. Pulse-chase analysis of the biosynthesis of these antigens indicated that F11 first recognizes the 75 and 77 K antigens in the absence of a 100K component suggesting strongly that these molecules contain an antigenic site recognized by F11. The 100 K antigen appears later in the pulse-chase analysis with kinetics that suggest some of the 75 and 77 K antigens are biosynthetic precursors of the 100 K antigen. This molecule is ultimately secreted into the extracellular media and appears to be a sialoglycoprotein judging from its sensitivity to neuraminidase. A cross-reactive species with an approximate Mr 90 K is also recognized by F11 in indirect immunoprecipitation analysis of spent media from a neuroblastoma cell line indicating that a common antigenic site exists on this secreted but structurally different neuroblastoma antigen. Thus, a combination of immunochemical and biosynthetic analyses of cell-associated and secreted antigens recognized by monoclonal antibody F11 demonstrate such molecules can differ structurally when isolated from the same or different tumor cells. These findings indicate the necessity to establish molecular profiles of melanoma-associated glycoprotein antigens recognized by monoclonal antibodies to characterize and define their potential biological functions within tumor cells.
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PMID:Immunochemical and biosynthetic analysis of monoclonal antibody-defined melanoma-associated antigen. 620 29

L-Fucose and D-galactose in low concentrations (0.27 or 2.7 mM) inhibited the induction of active Na+ channels in mouse and human neuroblastoma cells when the monosaccharides were added to the culture medium for 4 days with the inducing agent dimethyl sulfoxide. Active Na+ ionophores were determined by measurement of the toxin-stimulated efflux of 86Rb from the cells. At the same time, the amount of a radioactive glycoprotein (Mr 200,000), which was shown previously to be associated with neurite and membrane preparations from cells with active Na+ channels, was decreased. Cell growth and viability were not affected. The nonphysiological isomer D-fucose or the addition of D-glucose in the same concentration did not inhibit differentiation. Vibrio cholerae neuraminidase, added to the cells prior to the stimulation of 86Rb efflux by veratridine and scorpion venom, was inhibitory. The implications of these findings, which suggest a key role for glycoproteins in at least a portion of the excitability process, are discussed.
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PMID:Specific monosaccharide inhibition of active sodium channels in neuroblastoma cells. 626 60

Temperature-sensitive mutant G31 of vesicular stomatitis virus induces mouse neuroblastoma N-18 cells to fuse during infections that are nonpermissive for virus replication, but BHK-21 cells do not undergo the viral glycoprotein-mediated cell fusion. The viral glycoprotein was expressed at the cell surface of both N-18 and BHK-21 cells; therefore, the host cell specificity did not stem from an absence of the viral glycoprotein at the surface of BHK-21 cells. Cell fusion readily occurred between infected and uninfected N-18 cells in mixed cultures, demonstrating that the viral glycoprotein was interacting with an uninfected cell for the initial cell-cell interaction of the cell fusion. Mixing infected BHK-21 cells with uninfected N-18 cells resulted in cell fusion initiated by BHK-21 cell-synthesized viral glycoprotein, but 88% of the nuclei in polykaryocytes were N-18 nuclei. The N-18 cell fusion specificity was readily apparent when infected N-18 cells were mixed with uninfected BHK-21 cells; 98% of the nuclei in polykaryocytes were N-18 nuclei. Similar results also were obtained with mixed cultures of N-18 cells and primary astroglial cells. Thus, the viral glycoprotein synthesized in any of the cell types could initiate cell fusion, but the properties of plasma membranes of neuroblastoma cells appeared to be much more suitable for cell-cell fusion.
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PMID:Neuroblastoma cell membranes: specificity for cell fusion mediated by a temperature-sensitive mutant of vesicular stomatitis virus. 628 86

Addition of 50 micrograms/ml chloroquine to neuroblastoma cells 1 h before infection with temperature-sensitive mutant ts G31 (III) of vesicular stomatitis virus (VSV) prevented virus-induced cell fusion from occurring. Interestingly, addition of chloroquine after infection still inhibited cell fusion. Based on the number of fusion events required to produce the polykaryocytes observed, cell fusion was inhibited 92% when chloroquine was added 1 h post-infection and 77% when chloroquine was added 2 h post-infection. The inhibition of virus-induced cell fusion could not be accounted for by an inhibition of virus protein synthesis because the virus protein synthesis measured 6 h post-infection was 90% of that in untreated, infected cells with chloroquine added 1 h post-infection, and the same as untreated, infected cells when chloroquine was added 2 h post-infection. No virus proteins were made, however, when chloroquine was added before infection, which is consistent with a chloroquine-mediated inhibition of virus uncoating. The release of infectious virions was completely inhibited when chloroquine was added before infection or 1 or 2 h post-infection, which indicated an inhibition of virus maturation in the later stages of virus assembly. By indirect immunofluorescence the virus glycoprotein (G protein) could not be detected on the surface of chloroquine-treated, infected cells, but the G protein was present inside the treated cells. With 125I-labelled anti-G protein IgG, 16% of the G protein found on the surface of untreated, infected cells was on the cell surface when chloroquine was added 2 h post-infection. When chloroquine was removed from infected cells, the G protein accumulated at the cell surface, and this accumulation could not be prevented by tunicamycin, an inhibitor of glycosylation. Furthermore, galactose was incorporated into the G protein in the presence of chloroquine. Therefore, the VSV G protein was being synthesized and glycosylated in the presence of chloroquine but the drug prevented the expression of the glycoprotein at the cell surface during the final stages of G protein assembly.U
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PMID:Inhibition of vesicular stomatitis virus glycoprotein expression by chloroquine. 629 May 97

A Mr 58 000 subunit of the opiate receptor has been identified using tritiated fentanyl isothiocyanate, a potent opiate alkylating reagent with specificity for the delta-opiate receptor subclass. The subunit is alkylated in the presence of dextrorphan but not levorphanol. The specifically labelled protein was retained on columns of immobilized wheat germ agglutinin and is therefore presumably a glycoprotein. Partial purification of the Mr 58 000 opiate receptor subunit from neuroblastoma X glioma NG108-15 hybrid cell membranes is described.
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PMID:Identification of a Mr 58 000 glycoprotein subunit of the opiate receptor. 629 66

Glycoproteins were purified from a clonal cell line of mouse neuroblastoma, N-18, labeled metabolically with L-[3H]fucose. The purified radioactive glycoproteins were reconstituted into artificial phosphatidylcholine vesicles. When the vesicles were preloaded with cesium acetate and treated with neurotoxins to activate the Na+ channel, a shift in intravesicular density was observed to a less dense position after centrifugation on sucrose gradients. This shift was partially inhibited by tetrodotoxin, which prevents the activation of the Na+ channel. A similarly derived fraction of [14C]fucose-containing glycoproteins from a neuroblastoma cell line that does not possess excitable membranes, N1A-103, was reconstituted into phospholipid vesicles, and, after preloading with cesium ions, the fraction was combined with those of the 3H-labeled glycoproteins of the differentiated cells, N-18, which have excitable membranes. Only the 3H-labeled glycoprotein-containing vesicles were responsive to the neurotoxins, as shown by a shift in intravesicular density on sucrose gradients. These results are interpreted as a demonstration of the reconstitution of glycoproteins to form the activated Na+ channel. Comparison of the radioactive glycoprotein profiles after polyacrylamide gel electrophoresis showed that glycoproteins of Mr 200,000, Mr 165,000, and Mr 65,000 were common to the reconstituted fractions that were biologically active.
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PMID:Reconstitution in vitro of neurotoxin-responsive ion efflux by using membrane glycoproteins of neuroblastoma cells. 630 28

The protein synthesis of VSV infected CNS of mice was analysed by SDS-PAGE. Cellular and viral protein synthesis in the CNS were also compared to VSV infected neuroblastoma cells (clone NS 20) and fibroblasts (BHK21). Inhibition of host protein synthesis was observed in the three systems tested. However, this inhibition was shown to occur faster in neuroblastoma cells than in BHK cells, whereas it proceeded progressively in the brain. Thus the shut off of host cell protein synthesis by VSV seems to be a general phenomenon that occurs in vivo as well as in vitro. VSV protein from the CNS, or from neuroblastoma cells and fibroblasts were found to migrate similarly in SDS-PAGE. The viral L protein synthesis was found to be particularly active in the CNS, with respect to that observed in NS20 and BHK cells. The viral glycoprotein failed to be detected in the VSV infected mouse brain in our experimental conditions. The results show that VSV infection in vivo occurs with some difference with that of non neuronal cells, and that in vivo studies suggest the existence of cellular modulation that should be taken in account in the pathogenesis of this rhabdovirus.
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PMID:Protein synthesis in VSV infected CNS, neuroblastoma and BHK cell lines. 631 75

Laminin and fibronectin, the major noncollagenous matrix glycoproteins, were studied in connection with normal brain cells and neuroectodermal cell lines. Laminin, a Mr 900,000 dalton matrix glycoprotein and an essential component of basement membranes, was found to be produced by cultured cells of several malignant cell lines of neuroectodermal origin. In cultured mouse C1300 neuroblastoma line cells laminin was localized, by immunoelectron microscopy, to the rough endoplasmic reticulum and, to sites of cell-to-cell and cell-to-substratum adhesion. Further experiments on the intracellular transport of this glycoprotein in C1300 cells confirmed that laminin is, at least partially, transported through the Golgi pathway. These results favor a role for laminin in attachment and cellular interactions of malignant neuronal cells. Laminin was also found in connection with neurons and glial cells from mammalian brain. In primary cultures from developing rat brain the vast majority of non-neuronal cells (80%) expressed immunoreactivity for the glial fibrillary acidic protein, a cytoskeletal protein specific for astrocytes. During the first week in culture all the glial fibrillary acidic protein-positive cells, with the exception of mature-looking star-shaped astrocytes, exhibited immunoreactivity for laminin. The intracellular laminin disappeared gradually after a few weeks in culture, but an extensive laminin matrix persisted and seemed to be localized on the upper surface of the non-neuronal cells. The neurofilament-positive neurons were negative for laminin. Pretreatment of the cultures with the ionophore monensin, caused accumulation of laminin-immunoreactivity within the Golgi region, which confirmed that laminin is, indeed, produced by cultured astrocytes and secreted through the Golgi complex. No fibronectin immunoreactivity was found in the majority of glial cells. However, under culture conditions where fibronectin was omitted from the culture medium there was, in the primary cultures, a minor population of glial fibrillary acidic protein-positive flat glial cells that exhibited intracytoplasmic immunofluorescence for fibronectin. In the presence of fibronectin in culture medium no fibronectin-positive glial cells could be detected. It thus appears that laminin, and to a minor extent fibronectin, are proteins that normal glial cells are capable of producing under specific conditions. Laminin and fibronectin were localized in adult rat brain in capillary and meningeal structures.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Laminin and fibronectin in normal and malignant neuroectodermal cells. 638 23

Mouse monoclonal antibodies to several cell surface antigens of human ovarian and endometrial carcinomas have been produced. The distribution of the antigens was determined by mixed hemagglutination assays on 153 normal and malignant cell cultures of various types and by immuno-peroxidase staining of frozen sections of 27 normal adult and 24 fetal tissues. Five distinct antigens were characterized. MD144 antigen was detected on only a single ovarian carcinoma cell line and has the biochemical properties of a lipid. MH55 antigen is weakly expressed on ovarian and uterine cancer cell lines but not on other cells and tissues tested. MF61 antigen was detected on an ovarian carcinoma and some renal carcinoma cell lines but not on other cell lines tested. It was also detected by immunoperoxidase staining in the noncellular follicles of the thyroid and in uterine glandular epithelial cells. This antigen also has the properties of a lipid. MF116 antigen was detected on a proportion of ovarian, uterine, renal, and bladder carcinoma and neuroblastoma cell lines and on normal kidney epithelial cell cultures but not on other cell lines tested. It was not detected in sections of any normal tissue tested using the immunoperoxidase method. MF116 was readily detected in the spent culture medium but not in detergent-solubilized extracts of metabolically radiolabeled cells. This shed antigen is a glycoprotein of Mr 105,000 and isoelectric point lower than pH 4.0. MH94 antigen was detected on a proportion of ovarian, uterine, colon, breast, lung, cervical, and pancreatic carcinoma cell lines. In tissue sections it was detected in many but not all epithelia, predominantly in secretory epithelial cells. Antibody MH94 did not immunoprecipitate a detectable antigen.
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PMID:Cell surface antigens of human ovarian and endometrial carcinoma defined by mouse monoclonal antibodies. 658 12


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