title: Increased antigen presentation efficiency by coupling antigens to MHC class I trafficking signals.
abstract: Genetic modification of vaccines by linking the Ag to lysosomal or endosomal targeting signals has been used to route Ags into MHC class II processing compartments for improvement of CD4+ T cell responses. We report in this study that combining an N-terminal leader peptide with an MHC class I trafficking signal (MITD) attached to the C terminus of the Ag strongly improves the presentation of MHC class I and class II epitopes in human and murine dendritic cells (DCs). Such chimeric fusion proteins display a maturation state-dependent subcellular distribution pattern in immature and mature DCs, mimicking the dynamic trafficking properties of MHC molecules. T cell response analysis in vitro and in mice immunized with DCs transfected with Ag-encoding RNA showed that MITD fusion proteins have a profoundly higher stimulatory capacity than wild-type controls. This results in efficient expansion of Ag-specific CD8+ and CD4+ T cells and improved effector functions. We used CMVpp65 and NY-ESO-1 Ags to study preformed immune responses in CMV-seropositive individuals and cancer patients. We show that linking these Ags to the MITD trafficking signal allows simultaneous, polyepitopic expansion of CD8+ and CD4+ T cells, resulting in distinct CD8+ T cell specificities and a surprisingly broad and variable Ag-specific CD4+ repertoire in different individuals.
authors: Department of Internal Medicine III, Johannes-Gutenberg University, Mainz, Germany.
authors: Sebastian
authors: S
authors: Kreiter
authors: Abderraouf
authors: A
authors: Selmi
authors: Mustafa
authors: M
authors: Diken
authors: Martin
authors: M
authors: Sebastian
authors: Phillip
authors: P
authors: Osterloh
authors: Hansjörg
authors: H
authors: Schild
authors: Christoph
authors: C
authors: Huber
authors: Ozlem
authors: O
authors: Türeci
authors: Ugur
authors: U
authors: Sahin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017951:Antigen Presentation; D000941:Antigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology / Q000637:transplantation; D000939:Epitopes / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D021382:Protein Sorting Signals / Q000235:genetics; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D014162:Transfection; D014611:Vaccination; D014763:Viral Matrix Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D000941:Antigens; D000951:Antigens, Neoplasm; C104948:CTAG1B protein, human; D000939:Epitopes; D015395:Histocompatibility Antigens Class I; D008565:Membrane Proteins; D010750:Phosphoproteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D014763:Viral Matrix Proteins; C065418:cytomegalovirus matrix protein 65kDa