The tyrosine-containing cytoplasmic tail of CD1b is essential for its efficient presentation of bacterial lipid antigens

Immunity. 1998 Mar;8(3):341-51. doi: 10.1016/s1074-7613(00)80539-7.


CD1b is an antigen-presenting molecule that mediates recognition of bacterial lipid and glycolipid antigens by specific T cells. We demonstrate that the nine-amino acid cytoplasmic tail of CD1b contains all of the signals required for its normal endosomal targeting, and that the single cytoplasmic tyrosine is a critical component of the targeting motif. Mutant forms of CD1b lacking the endosomal targeting motif are expressed at high levels on the cell surface but are unable to efficiently present lipid antigens acquired either exogenously or from live intracellular organisms. These results define the functional role of the CD1b targeting motif in a physiologic setting and demonstrate its importance in delivery of this antigen-presenting molecule to appropriate intracellular compartments.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Antigen Presentation*
  • Antigens, Bacterial / immunology*
  • Antigens, Bacterial / metabolism
  • Antigens, CD1 / genetics
  • Antigens, CD1 / immunology*
  • Antigens, CD1 / metabolism
  • Biological Transport
  • Cell Compartmentation
  • Cell Line
  • Endosomes / immunology
  • Endosomes / metabolism
  • Fluorescent Antibody Technique
  • Humans
  • Lipids / immunology*
  • Lymphocyte Activation
  • Microscopy, Immunoelectron
  • Molecular Sequence Data
  • Mutagenesis
  • Mycobacterium tuberculosis / immunology
  • Protein Sorting Signals
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • T-Lymphocytes / immunology


  • Antigens, Bacterial
  • Antigens, CD1
  • Lipids
  • Protein Sorting Signals
  • Recombinant Fusion Proteins