title: Differential post-translational modification of CD63 molecules during maturation of human dendritic cells.
abstract: The capacity of dendritic cells to initiate T cell responses is related to their ability to redistribute MHC class II molecules from the intracellular MHC class II compartments to the cell surface. This redistribution occurs during dendritic cell development as they are converted from an antigen capturing, immature dendritic cell into an MHC class II-peptide presenting mature dendritic cell. During this maturation, antigen uptake and processing are down-regulated and peptide-loaded class II complexes become expressed in a stable manner on the cell surface. Here we report that the tetraspanin CD63, that associates with intracellularly localized MHC class II molecules in immature dendritic cells, was modified post-translationally by poly N-acetyl lactosamine addition during maturation. This modification of CD63 was accompanied by a change in morphology of MHC class II compartments from typical multivesicular organelles to structures containing densely packed lipid moieties. Post-translational modification of CD63 may be involved in the functional and morphological changes of MHC class II compartments that occur during dendritic cell maturation.
authors.affiliation: Basel Institute for Immunology, Basel, Switzerland.
authors.forename: Anneke
authors.initials: A
authors.lastname: Engering
authors.forename: Lotte
authors.initials: L
authors.lastname: Kuhn
authors.forename: Donna
authors.initials: D
authors.lastname: Fluitsma
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hoefsmit
authors.forename: Jean
authors.initials: J
authors.lastname: Pieters
mesh_terms: D017951:Antigen Presentation; D015703:Antigens, CD / Q000096:biosynthesis* / Q000737:chemistry; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism; D002455:Cell Division; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D058851:GPI-Linked Proteins; D005802:Genes, MHC Class II; D006031:Glycosylation; D006801:Humans; D007150:Immunohistochemistry; D010980:Platelet Membrane Glycoproteins / Q000096:biosynthesis* / Q000737:chemistry; D011233:Precipitin Tests; D020033:Protein Isoforms; D011499:Protein Processing, Post-Translational; D013347:Subcellular Fractions / Q000378:metabolism; D060149:Tetraspanin 30
chemical_list: D015703:Antigens, CD; C554586:CD63 protein, human; D015816:Cell Adhesion Molecules, Neuronal; D058851:GPI-Linked Proteins; D010980:Platelet Membrane Glycoproteins; D020033:Protein Isoforms; D060149:Tetraspanin 30; C095362:limbic system-associated membrane protein