Title:
Exosome-based nucleic acid drug delivery system

 

Speaker:
Dr. Yoshinobu Takakura
Graduate School of Pharmaceutical Sciences, Kyoto University

 

Abstract:
A variety of nucleic acid drugs have been studied as promising drug candidates for the treatment of a wide range of diseases, including cancer, viral diseases and other incurable diseases. For a successful therapy with these nucleic acid drugs, it is important to establish a rational strategy for the delivery of the nucleic acid drugs. Exosome are extracellular vesicles secreted from most types of cells. As exosomes are endogenous delivery vehicles responsible for intercellular transport of biomolecules including nucleic acids, natural and genetically engineered exosomes are expected to become potent delivery systems for nucleic acid therapeutics. We have developed novel methods of labeling exosomes with luciferase and 125I using fusion proteins to study pharmacokinetics of exogenously administered exosomes, one of the most important issues for the development of exosome-based delivery systems. Based on the findings, we recently developed a novel exosome-based antigen-adjuvant co-delivery system using genetically engineered tumor cell-derived exosomes containing endogenous tumor antigens and CpG DNA, a potent adjuvant. Vaccination with CpG DNA-modified exosomes exhibited a strong antitumor immunity, indicating that our novel exosome-based antigen-adjuvant co-delivery system can be a useful approach in cancer immunotherapy.

 

References:
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3.Charoenviriyakul C, Takahashi Y, Morishita M, Matsumoto A, Nishikawa M, Takakura Y. Cell type-specific and common characteristics of exosomes derived from mouse cell lines: yield, physicochemical properties, and pharmacokinetics. Eur J Pharm Sci, 96, 316-322, 2017.
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