The monoclonal antibody CHO-131 binds to a core 2 O-glycan terminated with sialyl-Lewis x, which is a functional glycan ligand for P-selectin

Blood. 2002 Jun 1;99(11):4063-9. doi: 10.1182/blood-2001-12-0265.


Core 2 O-glycans terminated with sialyl-Lewis x (sLe(X)) are functionally important oligosaccharides that endow particular macromolecules with high-affinity glycan ligands for the selectin family. To date, antibodies that recognize these structures on leukocytes have not been described. We characterize such a monoclonal antibody (mAb) here (CHO-131). The binding specificity of CHO-131 was directly examined by means of synthetic glycopeptides containing precise O-glycan structures. CHO-131 bound to sLe(X) extended from a core 2 branch (C2-O-sLe(X)), but CHO-131 demonstrated no reactivity if this oligosaccharide lacked fucose or if sLe(X) was extended from a core 1 branch. Using transfected cell lines, we found that CHO-131 binding required the functional activity of the glycosyltransferases alpha2,3-sialyltransferase, alpha1,3-fucosyltransferase-VII, and core 2 beta1,6 N-acetylglucosaminyltransferase (C2GnT). The C2-O-sLe(X) motif occurs primarily on sialomucins and has been directly shown to contribute to high-affinity P-selectin glycoprotein ligand-1 binding by P-selectin. Indeed, CHO-131 staining of neutrophils was diminished following sialomucin removal by O-glycoprotease, and its reactivity with transfected hematopoietic cell lines correlated with the expression of P-selectin ligands. CHO-131 also stained a small population of lymphocytes that were primarily CD3(+), CD4(+), and CD45RO(+) and represented a subset (37.8% +/- 18.3%) of cutaneous lymphocyte-associated antigen (CLA) T cells, distinguished by the mAb HECA-452, which detects sLe(X)-related glycans. Unlike anti-sLe(X) mAbs, CHO-131 binding also indicates C2GnT activity and demonstrates that CLA T cells are heterogeneous based on the glycan structures they synthesize. These findings support evidence that differential C2GnT activity results in T-cell subsets that express ligands for E-selectin, P-selectin, or both.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology*
  • Binding Sites
  • CHO Cells
  • Cell Line
  • Cricetinae
  • Enzyme-Linked Immunosorbent Assay / methods
  • Epitopes / immunology
  • Glycopeptides / chemistry
  • Glycopeptides / immunology
  • Hexosyltransferases / immunology
  • Humans
  • Ligands
  • Mice
  • Molecular Sequence Data
  • N-Acetylglucosaminyltransferases / immunology
  • Oligosaccharides / immunology*
  • P-Selectin / chemistry
  • P-Selectin / immunology*
  • Rats
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / immunology
  • Sialyl Lewis X Antigen
  • Transfection


  • Antibodies, Monoclonal
  • Epitopes
  • Glycopeptides
  • Ligands
  • Oligosaccharides
  • P-Selectin
  • Recombinant Proteins
  • Sialyl Lewis X Antigen
  • Hexosyltransferases
  • N-Acetylglucosaminyltransferases
  • beta-1,3-galactosyl-O-glycosyl-glycoprotein beta-1,6-acetylglucosaminyl transferase