Extracellular Vesicle Loading Via pH-Gradient Modification.

Extracellular vesicles (EVs) have emerged as key mediators of intercellular communication and consequently have the potential to be potent therapeutic vectors. Beyond their endogenous function, EVs are also being harnessed as drug delivery vehicles with possible benefits over synthetic nanoparticle systems. Despite advances in loading exogenous molecules into extracellular vesicles, efficient incorporation of nucleic acids remains a challenge due to aggregation and degradation. In this chapter, we detail a method to load EVs with negatively charged cargo, in particular nucleic acids, by modifying the internal pH of the vesicles to be acidic. This approach demonstrates that pH modification of EVs enables efficient loading of nucleic acids with functional cargo.