title: Trafficking of MHC class II molecules in the late secretory pathway.
abstract: Antigen presenting cells (APCs) alert the immune system to attack by extracellular organisms; APCs achieve this via internalization, degradation, and display of antigenic fragments on the cell surface by MHC class II molecules. These class II molecules bind to an accessory protein, termed the invariant chain, that ensures proper folding of the molecules. Invariant-chain binding also directs class II molecules to lysosomes, which are probably the most important sites for antigen loading. Endosomes are intermediates in the transport of class-II-invariant chain complexes to antigen-processing compartments, whereas trafficking of class II-peptide complexes to the membrane (and beyond) is less-well understood. Unlike other APCs, dendritic cells alter their capacity to present peptides via MHC class II molecules during differentiation, revealing a complex level of regulated antigen-presentation by this APC subtype.
authors.affiliation: Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Hiltbold
authors.forename: Paul A
authors.initials: PA
authors.lastname: Roche
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D003713:Dendritic Cells / Q000276:immunology*; D011992:Endosomes / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D021381:Protein Transport / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000949:Histocompatibility Antigens Class II