title: Extended presentation of specific MHC-peptide complexes by mature dendritic cells compared to other types of antigen-presenting cells.
abstract: Dendritic cells are known as the most potent antigen-presenting cells for the induction of T cell-mediated immune responses. To discriminate between the presentation of antigens and the co-stimulatory aspects of this high immunostimulatory capacity, we used recombinant antibodies with T cell receptor-like specificity to detect defined MHC-peptide complexes on living cells. Mature human dendritic cells (mDC) were compared with immature DC (iDC), monocytes, CD4(+) T lymphocytes, melanoma cells, T2 cells and B lymphoblastoid cells for their capacity to present MHC class I-restricted tumor-associated T cell epitopes and were found to display the specific peptides two to six times longer than other cells. The most short-lived peptide had an average half-life of 8.7 h on mDCvs. 3.5 h on B lymphoblastoid cells, while the most long-lived peptide had a half-life of 118.5 h vs. 20.7 h on these two cell types. The decay kinetics of specific MHC-peptide complexes on iDC were among the fastest observed. The high potency of dendritic cells to induce specific T cell responses is thus based, in addition to the expression of co-stimulatory molecules, on an extended antigenic memory, which increases the likelihood and the extent of contacts between dendritic cells and antigen-specific T cells.
authors.affiliation: Department of Dermatology, Charité, University Medicine Berlin, Humboldt University, Berlin, Germany.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Zehn
authors.forename: Cyril J
authors.initials: CJ
authors.lastname: Cohen
authors.forename: Yoram
authors.initials: Y
authors.lastname: Reiter
authors.forename: Peter
authors.initials: P
authors.lastname: Walden
mesh_terms: D017951:Antigen Presentation / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D045744:Cell Line, Tumor / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D015234:HLA-A Antigens / Q000276:immunology*; D006801:Humans; D007700:Kinetics; D018613:Microscopy, Confocal; D009000:Monocytes / Q000276:immunology; D010446:Peptide Fragments / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D019810:Sodium Azide
chemical_list: D000939:Epitopes; D015234:HLA-A Antigens; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell; D011994:Recombinant Proteins; D019810:Sodium Azide