Increased antigen presentation efficiency by coupling antigens to MHC class I trafficking signals.
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.
Kreiter
Sebastian
S
Department of Internal Medicine III, Johannes-Gutenberg University, Mainz, Germany.
Selmi
Abderraouf
A
Diken
Mustafa
M
Sebastian
Martin
M
Osterloh
Phillip
P
Schild
Hansjörg
H
Huber
Christoph
C
Türeci
Ozlem
O
Sahin
Ugur
U
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
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