title: Exosomes from plasmacytoma cells as a tumor vaccine.
abstract: Exosomes are membrane-bound vesicles derived from multivesicular bodies that are externalized by cells through fusion with the plasma membrane. Exosomes have been implicated in cell-to-cell signaling, and those derived from immunologic cells may be involved in both direct and cross-presentation of antigens to T cells. The research presented here evaluated their efficacy as a prophylactic cancer vaccine in a mouse plasmacytoma model. Plasmacytoma cells were shown to release exosomes in vitro, and vaccination with a single dose (5 microg) of exosome protein protected 80% of mice against challenge with wild-type tumors. Protection could be linked to the immune system since vaccinated mice generated specific cytotoxic T lymphocytes, the effects were not seen in SCID mice, and immunity was tumor-specific. Several proteins involved in immunity, including two potential tumor antigens (P1A and intracisternal A particle protein) as well as Hsp70, were demonstrated to be present in exosomes. The authors conclude that exosomes can induce tumor-specific immunity and prevent tumor development and are a potential strategy for future therapeutic tumor vaccination.
authors.affiliation: Department of Immunology, Laboratory of Molecular Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Altieri
authors.forename: A Nazmul H
authors.initials: AN
authors.lastname: Khan
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Tomasi
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019496:Cancer Vaccines / Q000276:immunology* / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D005089:Exocytosis; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D007167:Immunotherapy; D051379:Mice; D046529:Microscopy, Electron, Transmission; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D010954:Plasmacytoma / Q000276:immunology* / Q000378:metabolism* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D022142:Secretory Vesicles / Q000276:immunology* / Q000378:metabolism / Q000648:ultrastructure; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D006360:Heat-Shock Proteins; D012333:RNA, Messenger