Glycosylation-dependent inhibition of cutaneous lymphocyte-associated antigen expression: implications in modulating lymphocyte migration to skin

Blood. 2003 Jan 15;101(2):602-10. doi: 10.1182/blood-2002-06-1736. Epub 2002 Sep 5.

Abstract

Constitutive E-selectin expression on dermal microvascular endothelial cells plays a critical role in mediating rolling adhesive interactions of human skin-homing T cells and in pathologic accumulation of lymphocytes in skin. The major E-selectin ligand on human skin-homing T cells is cutaneous lymphocyte-associated antigen (CLA), a specialized glycoform of P-selectin glycoprotein ligand-1 (PSGL-1) defined by monoclonal antibody HECA-452. Since HECA-452 reactivity, and not PSGL-1 polypeptide itself, confers the specificity of human T cells to enter dermal tissue, inhibition of HECA-452 expression is a potential strategy for modulating lymphocyte migration to skin. In this study, we examined the efficacy of several well-characterized metabolic inhibitors of glycosylation and of a novel fluorinated analog of N-acetylglucosamine (2-acetamido-1,3,6-tri-O-acetyl-4-deoxy-4-fluoro-D-glucopyranose [4-F-GlcNAc]) to alter HECA-452 expression on human CLA(+) T cells and prevent cell tethering and rolling on selectins under shear stress. At concentrations that did not affect PSGL-1 expression, we found that swainsonine (inhibitor of complex-type N-glycan synthesis) had no effect on HECA-452 expression or selectin ligand activity, whereas benzyl-O-N-acetylgalactosamide (BAG; inhibitor of O-glycan biosynthesis) ablated HECA-452 expression on PSGL-1 and significantly lowered selectin ligand activity. We found that 4-F-GlcNAc (putative inhibitor of poly-N-acetyllactosamine biosynthesis) was more potent than BAG at lowering HECA-452 expression and selectin binding. In addition, we show that 4-F-GlcNAc was directly incorporated into native CLA expressed on T cells, indicating direct inhibition on poly-N-acetyllactosamine elongation and selectin-binding determinants on PSGL-1 O-glycans. These observations establish a potential treatment approach for targeting pathologic lymphocyte trafficking to skin and indicate that 4-F-GlcNAc may be a promising agent for treatment of dermal tropism associated with malignancies and inflammatory disorders.

Publication types

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

MeSH terms

  • Acetylglucosamine / analogs & derivatives*
  • Acetylglucosamine / pharmacology
  • Antigens, Differentiation, T-Lymphocyte
  • Antigens, Neoplasm
  • Chemotaxis, Leukocyte / drug effects
  • Glycosylation / drug effects
  • Humans
  • Leukocyte Rolling / drug effects*
  • Lymphocytes / cytology
  • Lymphocytes / drug effects*
  • Membrane Glycoproteins / antagonists & inhibitors*
  • Membrane Glycoproteins / biosynthesis
  • Membrane Glycoproteins / drug effects
  • Membrane Glycoproteins / physiology
  • Polysaccharides / biosynthesis
  • Skin Diseases / drug therapy
  • Skin Diseases / immunology
  • Structure-Activity Relationship
  • Swainsonine / pharmacology
  • Tunicamycin / pharmacology

Substances

  • Antigens, Differentiation, T-Lymphocyte
  • Antigens, Neoplasm
  • CTAGE1 protein, human
  • Membrane Glycoproteins
  • P-selectin ligand protein
  • Polysaccharides
  • Tunicamycin
  • 2-acetamido-1,3,6-tri-O-acetyl-4-deoxy-4-fluoroglucopyranose
  • poly-N-acetyllactosamine
  • Swainsonine
  • Acetylglucosamine