title: mRNA-transfected Dendritic Cells Expressing Polypeptides That Link MHC-I Presentation to Constitutive TLR4 Activation Confer Tumor Immunity.
abstract: Recently, we have developed a novel genetic platform for improving dendritic cell (DC) induction of peptide-specific CD8 T cells, based on membrane-anchored β2-microglobulin (β2m) linked to a selected antigenic peptide at its N-terminus and to the cytosolic domain of toll-like receptor (TLR)4 C-terminally. In vitro transcribed mRNA transfection of antigen presenting cells resulted in polypeptides that efficiently coupled peptide presentation to cellular activation. In the present study, we evaluated the immunogenicity of such constructs in mRNA-transfected immature murine bone marrow-derived DCs. We show that the encoded peptide β2m-TLR4 products were expressed at the cell surface up to 72 hours and stimulated the maturation of DCs. In vivo, these DCs prompted efficient peptide-specific T-cell activation and target cell killing which were superior to those induced by peptide-loaded, LPS-stimulated DCs. This superiority was also evident in the ability to protect mice from tumor progression following the administration of B16F10.9 melanoma cells and to inhibit the development of pre-established B16F10.9 tumors. Our results provide evidence that the products of two recombinant genes encoding for peptide-hβ2m-TLR4 and peptide-hβ2m-K(b) expressed from exogenous mRNA can cooperate to couple Major Histocompatibility Complex (MHC-I) peptide presentation to TLR-mediated signaling, offering a safe, economical and highly versatile genetic platform for a novel category of CTL-inducing vaccines.
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel; Laboratory of Immunology, MIGAL, Kiryat Shmona, Israel.
authors.forename: Gal
authors.initials: G
authors.lastname: Cafri
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Sharbi-Yunger
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Esther
authors.initials: E
authors.lastname: Tzehoval
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Zoya
authors.initials: Z
authors.lastname: Alteber
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Tamar
authors.initials: T
authors.lastname: Gross
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Ezra
authors.initials: E
authors.lastname: Vadai
authors.affiliation: Laboratory of Immunology, MIGAL, Kiryat Shmona, Israel; Department of Biotechnology, Tel-Hai College, Upper Galilee, Israel.
authors.forename: Alon
authors.initials: A
authors.lastname: Margalit
authors.affiliation: Laboratory of Immunology, MIGAL, Kiryat Shmona, Israel; Department of Biotechnology, Tel-Hai College, Upper Galilee, Israel.
authors.forename: Gideon
authors.initials: G
authors.lastname: Gross
authors.affiliation: Department of Immunology, Weizmann Institute of Science, Rehovot, Israel. Electronic address: lea.eisenbach@weizmann.ac.il.
authors.forename: Lea
authors.initials: L
authors.lastname: Eisenbach
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000166:cytology; D000951:Antigens, Neoplasm / Q000737:chemistry; D000970:Antineoplastic Agents / Q000737:chemistry; D001854:Bone Marrow Cells / Q000166:cytology; D019496:Cancer Vaccines / Q000276:immunology; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D003470:Culture Media; D003600:Cytosol / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology*; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000737:chemistry; D008546:Melanoma, Experimental; D051379:Mice; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism*; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000378:metabolism*; D001613:beta 2-Microglobulin / Q000378:metabolism*
chemical_list: D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D019496:Cancer Vaccines; D003470:Culture Media; D015395:Histocompatibility Antigens Class I; D008070:Lipopolysaccharides; D010455:Peptides; D012333:RNA, Messenger; C495345:TLR4 protein, human; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D001613:beta 2-Microglobulin