Association of distinct tetraspanins with MHC class II molecules at different subcellular locations in human immature dendritic cells.
Dendritic cells have the capacity to trigger T cell responses in lymphoid organs against antigens captured in the periphery. T cell stimulation depends on the ability of MHC class II molecules to present peptides at the cell surface that are acquired in MHC class II compartments. The high capacity of dendritic cells to stimulate T lymphocytes is related to their ability to regulate the distribution of MHC class II molecules intracellularly. To analyze the molecular components involved in the generation of MHC class II-peptide complexes in human immature dendritic cells, mAb were raised against purified MHC class II compartments. One of the antigens turned out to be CD63, a member of the tetraspanin superfamily. CD63 localized exclusively intracellularly where it associated with peptide-loaded class II molecules. In contrast, the tetraspanins CD9, CD53 and CD81 associated with class II molecules at the plasma membrane. Selective association of distinct tetraspanins may be involved in the regulation of MHC class II distribution in human dendritic cells.
Engering
A
A
Basel Institute for Immunology, Grenzacherstrasse 487, CH-4005 Basel, Switzerland.
Pieters
J
J
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism; D002454:Cell Differentiation / Q000276:immunology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000378:metabolism*; D006801:Humans; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism; D017434:Protein Structure, Tertiary; D013347:Subcellular Fractions / Q000276:immunology / Q000378:metabolism; D060149:Tetraspanin 30
D015703:Antigens, CD; C554586:CD63 protein, human; C554587:Cd63 protein, mouse; D015815:Cell Adhesion Molecules; D000949:Histocompatibility Antigens Class II; D008562:Membrane Glycoproteins; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30