title: Harnessing the exosome-induced immune response for cancer immunotherapy.
abstract: In recent years exosomes have emerged as potent stimulators of immune responses and as agents for cancer therapy. Exosomes can carry a broad variety of immunostimulatory molecules depending on the cell of origin and in vitro culture conditions. Dendritic cell-derived exosomes (dexosomes) have been shown to carry NK cell activating ligands and can be loaded with antigen to activate invariant NKT cells and to induce antigen-specific T and B cell responses. Dexosomes have been investigated as therapeutic agents against cancer in two phase I clinical trials, with a phase II clinical trial currently ongoing. Dexosomes were well tolerated but therapeutic success and immune activation were limited. Several reports suggest that multiple factors need to be considered in order to improve exosomal immunogenicity for cancer immunotherapy. These include antigen-loading strategies, exosome composition and exosomal trafficking in vivo. Hence, a better understanding of how to engineer and deliver exosomes to specific cells is crucial to generate strong immune responses and to improve the immunotherapeutic potential of exosomes.
authors.affiliation: Translational Immunology Unit, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Ulf
authors.initials: U
authors.lastname: Gehrmann
authors.affiliation: Translational Immunology Unit, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Tanja I
authors.initials: TI
authors.lastname: Näslund
authors.affiliation: Translational Immunology Unit, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Hiltbrunner
authors.affiliation: Translational Immunology Unit, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Pia
authors.initials: P
authors.lastname: Larssen
authors.affiliation: Translational Immunology Unit, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden. Electronic address: susanne.gabrielsson@ki.se.
authors.forename: Susanne
authors.initials: S
authors.lastname: Gabrielsson
mesh_terms: D000818:Animals; D017321:Clinical Trials, Phase I as Topic; D017322:Clinical Trials, Phase II as Topic; D003713:Dendritic Cells / Q000276:immunology; D055354:Exosomes / Q000276:immunology*; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D008213:Lymphocyte Activation / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D009369:Neoplasms / Q000276:immunology* / Q000628:therapy*
keywords: Adaptive immunity; Cancer immunotherapy; Dendritic cells; Exosomes; Innate immunity