Molecular profiles of the cell membrane bound and cytoplasmic forms of the human MHC class-II associated invariant polypeptides.
Several sub-types of histocompatibility class-II molecules are known to exist, including DR, DQ and DP, each subset organized in alpha and beta heterodimers. These molecules play a central role in immunorecognition via direct noncovalent binding of degraded nonself immunogenic peptides followed by ligand-interaction with T cells. In the cytoplasm the class-II alpha and beta chains associate, in addition with a third backbone molecule known as the invariant chain. In this study we show that all class-II subsets associate with the invariant chain probably from the same pool and that a subset of invariant chain is expressed as a cell surface subunit. This sub-unit, whose function is still unknown, was detected by flow-cytometry and by two-dimensional gel analysis followed by antibody-mediated immunoprecipitations.
Department of Biology, University of Essex, Colchester, UK.
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Fernandez
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Klidis
D000911:Antibodies, Monoclonal; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D003593:Cytoplasm / Q000276:immunology; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005455:Fluorescent Antibody Technique; D006681:HLA-D Antigens / Q000032:analysis*; D006801:Humans
D000911:Antibodies, Monoclonal; D006681:HLA-D Antigens; D016650:Fluorescein-5-isothiocyanate