Implications of the E-selectin S128R mutation for drug discovery

Glycobiology. 2014 Jul;24(7):592-601. doi: 10.1093/glycob/cwu026. Epub 2014 Mar 31.

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.

Keywords: E-selectin; S128R; sLex mimic; selectin antagonists; single-nucleotide polymorphism.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Sugars / pharmacology
  • Animals
  • CHO Cells
  • Cell Line, Tumor
  • Cricetinae
  • Cricetulus
  • Drug Discovery / methods*
  • E-Selectin / genetics
  • E-Selectin / metabolism*
  • Fetuins / pharmacology
  • Heparin / pharmacology
  • Humans
  • Ligands
  • Microarray Analysis
  • Mutation, Missense*
  • Oligosaccharides / pharmacology
  • Protein Binding
  • Sialyl Lewis X Antigen

Substances

  • Amino Sugars
  • E-Selectin
  • Fetuins
  • Ligands
  • Oligosaccharides
  • Sialyl Lewis X Antigen
  • sialyl-N-acetyllactosamine
  • Heparin