Involvement of secretory and endosomal compartments in presentation of an exogenous self-glycolipid to type II NKT cells

J Immunol. 2008 Mar 1;180(5):2942-50. doi: 10.4049/jimmunol.180.5.2942.

Abstract

Natural Killer T (NKT) cells recognize both self and foreign lipid Ags presented by CD1 molecules. Although presentation of the marine sponge-derived lipid alphaGalCer to type I NKT cells has been well studied, little is known about self-glycolipid presentation to either type I or type II NKT cells. Here we have investigated presentation of the self-glycolipid sulfatide to a type II NKT cell that specifically recognizes a single species of sulfatide, namely lyso-sulfatide but not other sulfatides containing additional acyl chains. In comparison to other sulfatides or alphaGalCer, lyso-sulfatide binds with lower affinity to CD1d. Although plate-bound CD1d is inefficient in presenting lyso-sulfatide at neutral pH, it is efficiently presented at acidic pH and in the presence of saposin C. The lysosomal trafficking of mCD1d is required for alphaGalCer presentation to type I NKT cells, it is not important for presentation of lyso-sulfatide to type II NKT cells. Consistently, APCs deficient in a lysosomal lipid-transfer protein effectively present lyso-sulfatide. Presentation of lyso-sulfatide is inhibited in the presence of primaquine, concanamycin A, monensin, cycloheximide, and an inhibitor of microsomal triglyceride transfer protein but remains unchanged following treatment with brefeldin A. Wortmannin-mediated inhibition of lipid presentation indicates an important role for the PI-3kinase in mCD1d trafficking. Our data collectively suggest that weak CD1d-binding self-glycolipid ligands such as lyso-sulfatide can be presented via the secretory and endosomal compartments. Thus this study provides important insights into the exogenous self-glycolipid presentation to CD1d-restricted T cells.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antigen Presentation / immunology*
  • Antigens, CD1 / immunology
  • Antigens, CD1 / metabolism
  • Antigens, CD1d
  • Autoantigens / immunology
  • Autoantigens / metabolism
  • Endosomes / immunology
  • Endosomes / metabolism*
  • Epitopes, T-Lymphocyte / immunology
  • Epitopes, T-Lymphocyte / metabolism
  • Female
  • Galactosylceramides / immunology*
  • Galactosylceramides / metabolism
  • Hybridomas
  • Killer Cells, Natural / classification
  • Killer Cells, Natural / immunology*
  • Killer Cells, Natural / metabolism
  • Ligands
  • Mice
  • Mice, Inbred C57BL
  • Secretory Vesicles / immunology
  • Secretory Vesicles / metabolism*
  • Sulfoglycosphingolipids / immunology*
  • Sulfoglycosphingolipids / metabolism
  • T-Lymphocyte Subsets / classification
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / metabolism

Substances

  • Antigens, CD1
  • Antigens, CD1d
  • Autoantigens
  • Epitopes, T-Lymphocyte
  • Galactosylceramides
  • Ligands
  • Sulfoglycosphingolipids