Autophagy promotes MHC class II presentation of peptides from intracellular source proteins

Proc Natl Acad Sci U S A. 2005 May 31;102(22):7922-7. doi: 10.1073/pnas.0501190102. Epub 2005 May 13.


MHC-peptide complexes mediate key functions in adaptive immunity. In a classical view, MHC-I molecules present peptides from intracellular source proteins, whereas MHC-II molecules present antigenic peptides from exogenous and membrane proteins. Nevertheless, substantial crosstalk between these two pathways has been observed. We investigated the influence of autophagy on the MHC-II ligandome and demonstrated that peptide presentation is altered considerably upon induction of autophagy. The presentation of peptides from intracellular and lysosomal source proteins was strongly increased on MHC-II in contrast with peptides from membrane and secreted proteins. In addition, autophagy influenced the MHC-II antigen-processing machinery. Our study illustrates a profound influence of autophagy on the class II peptide repertoire and suggests that this finding has implications for the regulation of CD4(+) T cell-mediated processes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antigen Presentation / immunology*
  • Autophagy / immunology*
  • B-Lymphocytes / immunology
  • Cadaverine / analogs & derivatives*
  • Cysteine Endopeptidases / metabolism
  • Gene Expression / immunology*
  • Histocompatibility Antigens Class II / immunology*
  • Histocompatibility Antigens Class II / metabolism
  • Humans
  • Ligands
  • Lysosomes / immunology
  • Lysosomes / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Peptides / genetics
  • Peptides / immunology*
  • Peptides / metabolism


  • Histocompatibility Antigens Class II
  • Ligands
  • Peptides
  • Cysteine Endopeptidases
  • monodansylcadaverine
  • Cadaverine