Sequential deletion of CD63 identifies topologically distinct scaffolds for surface engineering of exosomes in living human cells.

Exosomes are cell-derived extracellular vesicles that have great potential in the field of nano-medicine. However, a fundamental challenge in the engineering of exosomes is the design of biocompatible molecular scaffolds on their surface to enable cell targeting and therapeutic functions. CD63 is a hallmark protein of natural exosomes that is highly enriched on the external surface of the membrane.

AAV-based dual-reporter circuit for monitoring cell signaling in living human cells.

Background: High-throughput methods based on molecular reporters have greatly advanced our knowledge of cell signaling in mammalian cells. However, their ability to monitor various types of cells is markedly limited by the inefficiency of reporter gene delivery. Recombinant adeno-associated virus (AAV) vectors are efficient tools widely used for delivering and expressing transgenes in diverse animal cells in vitro and in vivo.

Pseudotyping exosomes for enhanced protein delivery in mammalian cells.

Exosomes are cell-derived nanovesicles that hold promise as living vehicles for intracellular delivery of therapeutics to mammalian cells. This potential, however, is undermined by the lack of effective methods to load exosomes with therapeutic proteins and to facilitate their uptake by target cells. Here, we demonstrate how a vesicular stomatitis virus glycoprotein (VSVG) can both load protein cargo onto exosomes and increase their delivery ability via a pseudotyping mechanism.

Development of exosome surface display technology in living human cells.

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.