title: Implications of the E-selectin S128R mutation for drug discovery.
abstract: The C-type lectin E-selectin mediates the rolling of circulating leukocytes on vascular endothelial cells during the inflammatory process. In numerous studies, the S128R mutation of the E-selectin was associated with cardiovascular and autoimmune diseases. There is evidence that the S128R E-selectin mutation leads to a loss in ligand specificity, thus increasing leukocyte recruitment. Apart from the natural tetrasaccharide ligand sialyl Lewis(x) (sLe(x)), it has previously been proposed that non-fucosylated carbohydrates also bind to S128R E-selectin. To evaluate the therapeutic potential of the antagonism of the E-selectin mutant, ligand specificity was reinvestigated on a molecular basis. We determined the ligand specificity of wild-type and S128R E-selectin in a target-based competitive assay, a glycan array screen and cell-based binding assays under static and flow conditions. Regarding ligand-specificity, the binding properties of S128R E-selectin were identical to those of wt E-selectin, i.e., no mutant-specific binding of 3'-sialyl-N-acetyllactosamine, heparin, fetuin and K562 cells was observed. Additionally, the binding affinities of glycomimetic E-selectin antagonists were identical for wt and S128R E-selectin. Overall, the previous reports on carbohydrate ligand promiscuity of S128R E-selectin could not be confirmed.
authors.affiliation: Institute of Molecular Pharmacy, Pharmacenter.
authors.forename: Roland C
authors.initials: RC
authors.lastname: Preston
authors.affiliation: Institute of Molecular Pharmacy, Pharmacenter.
authors.forename: Said
authors.initials: S
authors.lastname: Rabbani
authors.affiliation: Institute of Molecular Pharmacy, Pharmacenter.
authors.forename: Florian P C
authors.initials: FP
authors.lastname: Binder
authors.affiliation: Department of Biochemistry, Biocenter, University of Basel, Klingelbergstrasse 50, CH-4056 Basel, Switzerland.
authors.forename: Suzette
authors.initials: S
authors.lastname: Moes
authors.affiliation: GlycoMimetics, Inc., Gaithersburg, MD 20879, USA.
authors.forename: John L
authors.initials: JL
authors.lastname: Magnani
authors.affiliation: Institute of Molecular Pharmacy, Pharmacenter beat.ernst@unibas.ch.
authors.forename: Beat
authors.initials: B
authors.lastname: Ernst
mesh_terms: D000606:Amino Sugars / Q000494:pharmacology; D000818:Animals; D016466:CHO Cells; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D055808:Drug Discovery / Q000379:methods*; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism*; D060748:Fetuins / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D008024:Ligands; D046228:Microarray Analysis; D020125:Mutation, Missense; D009844:Oligosaccharides / Q000494:pharmacology; D011485:Protein Binding; D000080506:Sialyl Lewis X Antigen
chemical_list: D000606:Amino Sugars; D019040:E-Selectin; D060748:Fetuins; D008024:Ligands; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; C032269:sialyl-N-acetyllactosamine; D006493:Heparin
keywords: E-selectin; S128R; sLex mimic; selectin antagonists; single-nucleotide polymorphism