title: Fucosylation of disaccharide precursors of sialyl LewisX inhibit selectin-mediated cell adhesion.
abstract: We showed previously that HL-60 and F9 mouse embryonal carcinoma cells will take up and deblock peracetylated Galbeta1-4GlcNAcbeta-O-naphthalenemethanol (Galbeta1-4GlcNAc-NM) and use the disaccharide as a primer of oligosaccharide chains (Sarkar, A. K., Fritz, T. A., Taylor, W. H., and Esko, J. D. (1995) Proc. Natl. Acad. Sci. U. S. A. 92, 3323-3327). We now report that another disaccharide, acetylated GlcNAcbeta1-3Gal-naphthalenemethanol (GlcNAcbeta1-3Gal-NM), has even greater potency and that both compounds will inhibit sialyl LewisX (sLex)-dependent cell adhesion. When fed to U937 cells, acetylated forms of Galbeta1-4GlcNAc-NM and GlcNAcbeta1-3Gal-NM primed oligosaccharides in a dose-dependent manner. Analysis of compounds assembled on Galbeta1-4GlcNAc-NM showed only one product, namely Galbeta1-4(Fucalpha1-3)GlcNAc-NM. In contrast, GlcNAcbeta1-3Gal-NM generated Galbeta1-4GlcNAcbeta1-3Gal-NM, Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-3Gal-NM, NeuAcalpha2-3Galbeta1-4GlcNAcbeta1-3Gal-NM, and NeuAcalpha2-3Galbeta1-4(Fucalpha1-3)GlcNAcbeta1- 3Gal-NM. Both compounds decreased the incorporation of [3H]fucose into cellular glycoconjugates, without affecting the incorporation of [3H]mannosamine, a precursor of sialic acid residues. Moreover, the overall extent of sialylation was not affected based on the reactivity of cells to fluorescein isothiocyanate-conjugated Maackia amurensis lectin. Priming inhibited expression of sLex on cell surface glycoconjugates, which reduced E-selectin-dependent cell adhesion to tumor necrosis factor-alpha-activated human umbilical vein endothelial cells. GlcNAcbeta1-3Gal-NM and Galbeta1-4GlcNAc-NM represent starting points for making enzyme-specific, site-directed inhibitors of glycosyltransferases that could act in living cells.
authors.affiliation: Division of Cellular and Molecular Medicine, Glycobiology Program, UCSD Cancer Center, University of California, San Diego, La Jolla, California 92093-0687, USA.
authors.forename: A K
authors.initials: AK
authors.lastname: Sarkar
authors.forename: K S
authors.initials: KS
authors.lastname: Rostand
authors.forename: R K
authors.initials: RK
authors.lastname: Jain
authors.forename: K L
authors.initials: KL
authors.lastname: Matta
authors.forename: J D
authors.initials: JD
authors.lastname: Esko
mesh_terms: D000107:Acetylation; D000818:Animals; D002240:Carbohydrate Sequence; D002448:Cell Adhesion / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004187:Disaccharides / Q000378:metabolism*; D019040:E-Selectin / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000378:metabolism; D005643:Fucose / Q000378:metabolism*; D006801:Humans; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen / Q000378:metabolism; D051379:Mice; D008956:Models, Chemical; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism; D000080506:Sialyl Lewis X Antigen; D014407:Tumor Cells, Cultured
chemical_list: D004187:Disaccharides; D019040:E-Selectin; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; D009844:Oligosaccharides; D012794:Sialic Acids; D000080506:Sialyl Lewis X Antigen; D005643:Fucose