title: Development of exosome surface display technology in living human cells.
abstract: Surface display technology is an emerging key player in presenting functional proteins for targeted drug delivery and therapy. Although a number of technologies exist, a desirable mammalian surface display system is lacking. Exosomes are extracellular vesicles that facilitate cell-cell communication and can be engineered as nano-shuttles for cell-specific delivery. In this study, we report the development of a novel exosome surface display technology by exploiting mammalian cell secreted nano-vesicles and their trans-membrane protein tetraspanins. By constructing a set of fluorescent reporters for both the inner and outer surface display on exosomes at two selected sites of tetraspanins, we demonstrated the successful exosomal display via gene transfection and monitoring fluorescence in vivo. We subsequently validated our system by demonstrating the expected intracellular partitioning of reporter protein into sub-cellular compartments and secretion of exosomes from human HEK293 cells. Lastly, we established the stable engineered cells to harness the ability of this robust system for continuous production, secretion, and uptake of displayed exosomes with minimal impact on human cell biology. In sum, our work paved the way for potential applications of exosome, including exosome tracking and imaging, targeted drug delivery, as well as exosome-mediated vaccine and therapy.
authors.affiliation: Department of Bioengineering, Santa Clara University, 500 El Camino Real, Santa Clara, CA CA95053, USA. Electronic address: zstickney@scu.edu.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Stickney
authors.affiliation: Department of Bioengineering, Santa Clara University, 500 El Camino Real, Santa Clara, CA CA95053, USA. Electronic address: jlosacco@scu.edu.
authors.forename: Joseph
authors.initials: J
authors.lastname: Losacco
authors.affiliation: Department of Bioengineering, Santa Clara University, 500 El Camino Real, Santa Clara, CA CA95053, USA. Electronic address: smmcdevitt@scu.edu.
authors.forename: Sophie
authors.initials: S
authors.lastname: McDevitt
authors.affiliation: Department of Bioengineering, Santa Clara University, 500 El Camino Real, Santa Clara, CA CA95053, USA. Electronic address: zzhang@scu.edu.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Bioengineering, Santa Clara University, 500 El Camino Real, Santa Clara, CA CA95053, USA. Electronic address: blu2@scu.edu.
authors.forename: Biao
authors.initials: B
authors.lastname: Lu
mesh_terms: D061505:Cell Surface Display Techniques / Q000379:methods*; D055354:Exosomes / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D053758:Nanoparticles; D054730:Protein Interaction Domains and Motifs; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D059010:Single-Cell Analysis / Q000379:methods; D060149:Tetraspanin 30 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D022161:Transport Vesicles / Q000378:metabolism; D000097573:Red Fluorescent Protein
chemical_list: D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D060149:Tetraspanin 30; D000097573:Red Fluorescent Protein; C554586:CD63 protein, human
keywords: CD63; CD81; CD9; Exosome; Surface display