Date of Award
Santa Clara : Santa Clara University, 2018.
Master of Science (MS)
Exosomes are naturally secreted nanovesicles derived from mammalian cells that are used for intercellular communication in vivo. As a result, they can potentially be used for intracellular delivery of therapeutics for disease treatment. We have developed an exosome pseudotyping approach using vesicular stomatitis virus glycoprotein (VSVG) to produce protein chimeras that optimize production of modified exosomes containing protein therapeutics and facilitate effective delivery to their target cells. To the VSVG transmembrane scaffold, we have fused both fluorescent and luminescent reporters for exosome tracking/visualization and quantification of activity respectively. Through our design, we have shown the biogenesis of VSVG modified exosomes from transfected producer cells through fluorescence imaging and the production of a VSVG-based stable cell line. In addition, we have characterized isolated engineered exosomes and shown that they exhibited the correct size, distribution, and molecular markers, while retaining the bioactivity of their protein cargo. Furthermore, we show that our engineered exosomes and their protein cargo are internalized by multiple cell lines into the endosomal and lysosomal compartments of those cells. Lastly, these modified exosomes can confer their bioactive cargo, either a luminescent reporter or puromycin resistance into these target cells. In summary, this study presents a novel approach to exosome engineering to enhance therapeutic protein loading and delivery, and more importantly, shows the delivery of modified exosomes to intracellular lysosomal compartments. This aspect leads to the assumption that in future studies, these engineered exosomes can be used as a vehicle for delivery of therapeutic proteins for treatment of lysosomal storage diseases.
Levy, Daniel, "Lysosomal Delivery of Bioactive Proteins to Living Human Cells via Engineered Exosomes" (2018). Bioengineering Master's Theses. 4.