title: Down-regulation of class II major histocompatibility complex molecules on antigen presenting cells after interaction with helper T cells.
abstract: The recognition of antigenic peptides by CD4+ helper T cells is demonstrated here to result in a dramatic (up to 90%) decrease in expression of major histocompatibility complex (MHC) class II molecules on the surface of antigen-presenting cells (APC). The reduction is selective to the class II isotype presenting the antigen, but if affects both allelic forms of the same isotype in heterozygous APC. The observed MHC down-regulation requires a specific T cell receptor-peptide-class II interaction, a direct contact between T cell and APC, and the involvement of CD2 molecules. These findings have important implications for the regulation of immune response, self tolerance, and autoimmunity.
authors.affiliation: Department of Inflammation/Autoimmune Diseases, Hoffmann-La Roche, Inc., Nutley, New Jersey, 07110-1199, USA.
authors.forename: D
authors.initials: D
authors.lastname: Vidović
authors.forename: F
authors.initials: F
authors.lastname: Falcioni
authors.forename: D R
authors.initials: DR
authors.lastname: Bolin
authors.forename: Z A
authors.initials: ZA
authors.lastname: Nagy
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D000941:Antigens / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology*; D002450:Cell Communication; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D015536:Down-Regulation; D006183:H-2 Antigens / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology; D018089:Superantigens / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000941:Antigens; D000954:Antigens, Surface; D017077:Culture Media, Conditioned; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D010446:Peptide Fragments; D018089:Superantigens