title: Transport of peptide-MHC class II complexes in developing dendritic cells.
abstract: Major histocompatibility complex class II (MHC II) molecules capture peptides within the endocytic pathway to generate T cell receptor (TCR) ligands. Immature dendritic cells (DCs) sequester intact antigens in lysosomes, processing and converting antigens into peptide-MHC II complexes upon induction of DC maturation. The complexes then accumulate in distinctive, nonlysosomal MHC II+ vesicles that appear to migrate to the cell surface. Although the vesicles exclude soluble lysosomal contents and antigen-processing machinery, many contain MHC I and B7 costimulatory molecules. After arrival at the cell surface, the MHC and costimulatory molecules remain clustered. Thus, transport of peptide-MHC II complexes by DCs not only accomplishes transfer from late endocytic compartments to the plasma membrane, but does so in a manner that selectively concentrates TCR ligands and costimulatory molecules for T cell contact.
authors.affiliation: Department of Cell Biology and Section of Immunobiology, Ludwig Institute for Cancer Research, Yale University School of Medicine, 333 Cedar Street, Post Office Box 208002, New Haven, CT 06520-8002, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Turley
authors.forename: K
authors.initials: K
authors.lastname: Inaba
authors.forename: W S
authors.initials: WS
authors.lastname: Garrett
authors.forename: M
authors.initials: M
authors.lastname: Ebersold
authors.forename: J
authors.initials: J
authors.lastname: Unternaehrer
authors.forename: R M
authors.initials: RM
authors.lastname: Steinman
authors.forename: I
authors.initials: I
authors.lastname: Mellman
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D017951:Antigen Presentation; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D051940:B7-2 Antigen; D001692:Biological Transport; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism*; D004705:Endocytosis; D011992:Endosomes / Q000276:immunology / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000276:immunology / Q000378:metabolism; D000949:Histocompatibility Antigens Class II / Q000276:immunology / Q000378:metabolism*; D007700:Kinetics; D008024:Ligands; D008070:Lipopolysaccharides / Q000276:immunology; D008247:Lysosomes / Q000276:immunology / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D009113:Muramidase / Q000276:immunology / Q000378:metabolism*; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D051940:B7-2 Antigen; D019086:Bridged Bicyclo Compounds, Heterocyclic; C497965:Cd86 protein, mouse; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; C111388:I-Ak antigen; C024138:I-E-antigen; D008024:Ligands; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell; D013844:Thiazoles; D053778:Thiazolidines; C066759:hen egg lysozyme peptide (46-61); D009113:Muramidase; C037068:latrunculin B