title: Negative regulation by HLA-DO of MHC class II-restricted antigen processing.
abstract: HLA-DM is a major histocompatibility complex (MHC) class II-like molecule that facilitates antigen processing by catalyzing the exchange of invariant chain-derived peptides (CLIP) from class II molecules for antigenic peptides. HLA-DO is a second class II-like molecule that physically associates with HLA-DM in B cells. HLA-DO was shown to block HLA-DM function. Purified HLA-DM-DO complexes could not promote peptide exchange in vitro. Expression of HLA-DO in a class II+ and DM+, DO- human T cell line caused the accumulation of class II-CLIP complexes, indicating that HLA-DO blocked DM function in vivo and suggesting that HLA-DO is an important modulator of class II-restricted antigen processing.
authors.affiliation: Section of Immunobiology, Howard Hughes Medical Institute, Yale University School of Medicine, 310 Cedar Street, New Haven, CT 06510, USA.
authors.forename: L K
authors.initials: LK
authors.lastname: Denzin
authors.forename: D B
authors.initials: DB
authors.lastname: Sant'Angelo
authors.forename: C
authors.initials: C
authors.lastname: Hammond
authors.forename: M J
authors.initials: MJ
authors.lastname: Surman
authors.forename: P
authors.initials: P
authors.lastname: Cresswell
mesh_terms: D000595:Amino Acid Sequence; D017951:Antigen Presentation; D000944:Antigens, Differentiation, B-Lymphocyte / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology*; D006681:HLA-D Antigens / Q000378:metabolism*; D015803:HLA-DR3 Antigen / Q000378:metabolism; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D013601:T-Lymphocytes / Q000276:immunology*; D015534:Trans-Activators / Q000235:genetics; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; C416186:H-2O antigen; C416189:H2-M antigens; D006681:HLA-D Antigens; C084245:HLA-DM antigens; C046148:HLA-DO antigens; D015803:HLA-DR3 Antigen; D000949:Histocompatibility Antigens Class II; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D015534:Trans-Activators; C045084:invariant chain