title: Dendritic cell-derived exosomes stimulate stronger CD8+ CTL responses and antitumor immunity than tumor cell-derived exosomes.
abstract: Exosomes (EXO) derived from dendritic cells (DC) and tumor cells have been used to stimulate antitumor immune responses in animal models and in clinical trials. However, there has been no side-by-side comparison of the stimulatory efficiency of the antitumor immune responses induced by these two commonly used EXO vaccines. In this study, we selected to study the phenotype characteristics of EXO derived from a transfected EG7 tumor cells expressing ovalbumin (OVA) and OVA-pulsed DC by flow cytometry. We compared the stimulatory effect in induction of OVA-specific immune responses between these two types of EXO. We found that OVA protein-pulsed DCOVA-derived EXO (EXODC) can more efficiently stimulate naïve OVA-specific CD8+ T cell proliferation and differentiation into cytotoxic T lymphocytes in vivo, and induce more efficient antitumor immunity than EG7 tumor cell-derived EXO (EXOEG7). In addition, we elucidated the important role of the host DC in EXO vaccines that the stimulatory effect of EXO is delivered to T cell responses by the host DC. Therefore, DC-derived EXO may represent a more effective EXO-based vaccine in induction of antitumor immunity.
authors.affiliation: Research Unit, Division of Health Research, Saskatchewan Cancer Agency, Department of Oncology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 4H4, Canada.
authors.forename: Siguo
authors.initials: S
authors.lastname: Hao
authors.forename: Ou
authors.initials: O
authors.lastname: Bai
authors.forename: Jinying
authors.initials: J
authors.lastname: Yuan
authors.forename: Mabood
authors.initials: M
authors.lastname: Qureshi
authors.forename: Jim
authors.initials: J
authors.lastname: Xiang
mesh_terms: D000818:Animals; D019496:Cancer Vaccines / Q000276:immunology / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002478:Cells, Cultured; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D004195:Disease Models, Animal; D005089:Exocytosis; D007109:Immunity; D016130:Immunophenotyping; D008175:Lung Neoplasms / Q000276:immunology / Q000556:secondary / Q000628:therapy*; D008213:Lymphocyte Activation; D008546:Melanoma, Experimental / Q000276:immunology / Q000556:secondary / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009368:Neoplasm Transplantation; D010047:Ovalbumin / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*; D013945:Thymoma / Q000276:immunology* / Q000378:metabolism; D022161:Transport Vesicles / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation
chemical_list: D019496:Cancer Vaccines; D010047:Ovalbumin