A DNA Origami-Based Cobweb Facilitates Precise and Receptor-Interference Free Modification of Extracellular Vesicle Mimetic for Enhanced Delivery Efficacy

The approach of tailoring ligands on the surface of extracellular vesicle (EV)-based drugs has been pivotal in achieving an effective EV-based therapeutic delivery. However, indiscriminate modifications to the membranes can diminish efficacy due to uncontrollable binding affinities and disruptions in the EV membrane functionality, often caused by disordered ligand coverage. In this study, we present an approach for affinity-tunable and receptor-interference-free extracellular vesicle mimetic (EVM) functionalization. We employ a soft wireframe DNA origami-based "cobweb" to achieve a customized spatial distribution of targeting ligands on the EVM surface, allowing for precise control over the cellular affinity and subsequent EVM uptake. Moreover, by utilizing the hollow structure of the DNA origami cobweb, we are able to program EVM without compromising the native functions of their membrane proteins such as CD47-mediated immune evasion. We believe that our strategy will provide a versatile platform for the targeted delivery of EVM-based drugs with high efficiency.