Exosome-Based Transfection

Exosomes are mammalian extracellular vesicles that are involved in intracellular communication. The discovery of RNA in exosomes established their capacity to function as RNA delivery vehicles in gene therapy applications. The main obstacle to the gene therapy approach is finding suitable vehicles to deliver therapeutic genetic molecules. Conventional delivery methods employ viruses or liposomes, however, the clinical applications of these vehicles are limited by shortcomings such as cytotoxicity and immunogenicity. On the other hand, exosomes could represent a more effective delivery vehicle because they are natural transporters of RNA. The purpose of the research presented in this thesis was to investigate the transfection ability and cytotoxicity of exosomes. Exosomes were used to transfect mouse embryonic fibroblasts (MEFs) in vitro with mRNA for Ascl1, Brn2 and Myt1l (ABM), a combination of transcription factors that reprograms fibroblasts into neurons. The exosomes were prepared by isolating them from the supernatant of MEFs transfected with ABM plasmids using bulk electroporation (BEP). Exosome cytotoxicity was compared to that of a commercial liposome formulation by incubating them with MEFs and determining cell viability. The results indicate that exosomes successfully transfected MEFs with ABM mRNA. In addition, the exosomes were less cytotoxic than the liposomes. In fact, viability of MEFs was minimally impacted by incubation with the exosomes. Further research in exosome-based transfection could one day allow researchers to harness their intrinsic properties with the purpose of delivering RNA for gene therapy.No embargoAcademic Major: Chemical Engineerin