title: acDCs enhance human antigen-specific T-cell responses.
abstract: Detection of human Ag-specific T cells is limited by sensitivity and blood requirements. As dendritic cells (DCs) can potently stimulate T cells, we hypothesized that their induction in PBMCs in situ could link Ag processing and presentation to Ag-specific T-cell activation. To this end, unfractionated PBMCs (fresh or frozen) or whole blood were incubated for 48 hours with protein or peptide Ag together with different DC-activating agents to rapidly and sequentially induce, pulse, and mature DCs. DC activation was therefore lined up with Ag recognition by neighboring T cells, thus telescoping the sequential steps of T-cell activation. Efficient processing of protein Ags made prior knowledge of epitopes and HLA restrictions dispensable. While reducing stimulation time, manipulation and blood requirements, in situ DC induction specifically amplified Ag-specific T-cell responses (cytokine secretion, proliferation, CD137/CD154 up-regulation, and binding of peptide-HLA multimers). IL-1β, although released by DCs, was also secreted in an Ag-specific fashion, thus providing an indirect biomarker of T-cell responses. These accelerated cocultured DC (acDC) assays offered a sensitive means with which to evaluate T-cell responses to viral and melanoma Ag vaccination, and may therefore find application for immune monitoring in viral, tumor, autoimmune, and transplantation settings.
authors.affiliation: Inserm U986, Diabetes & Autoimmunity Research Laboratory, Paris, France.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Martinuzzi
authors.forename: Georgia
authors.initials: G
authors.lastname: Afonso
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Gagnerault
authors.forename: Gaetano
authors.initials: G
authors.lastname: Naselli
authors.forename: Diana
authors.initials: D
authors.lastname: Mittag
authors.forename: Béhazine
authors.initials: B
authors.lastname: Combadière
authors.forename: Christian
authors.initials: C
authors.lastname: Boitard
authors.forename: Nathalie
authors.initials: N
authors.lastname: Chaput
authors.forename: Laurence
authors.initials: L
authors.lastname: Zitvogel
authors.forename: Leonard C
authors.initials: LC
authors.lastname: Harrison
authors.forename: Roberto
authors.initials: R
authors.lastname: Mallone
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D000941:Antigens / Q000008:administration & dosage; D019496:Cancer Vaccines / Q000008:administration & dosage; D049109:Cell Proliferation; D018920:Coculture Techniques; D016207:Cytokines / Q000096:biosynthesis / Q000097:blood; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D000939:Epitopes / Q000008:administration & dosage; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006680:HLA Antigens / Q000008:administration & dosage; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology; D008213:Lymphocyte Activation; D008545:Melanoma / Q000276:immunology / Q000628:therapy; D058950:Melanoma-Specific Antigens / Q000008:administration & dosage; D051379:Mice; D011994:Recombinant Proteins; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D014611:Vaccination
chemical_list: D000941:Antigens; D019496:Cancer Vaccines; D016207:Cytokines; D000939:Epitopes; D006680:HLA Antigens; D058950:Melanoma-Specific Antigens; D011994:Recombinant Proteins; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor