Exosome-Mediated Targeted Delivery of miRNAs.

Many types of cells release phospholipid membrane vesicles that are thought to play key roles in cell-cell communication, antigen presentation, and the spread of infectious agents. These membrane vesicles, derived from the late endosomes, are called exosomes. Various proteins, messenger RNAs (mRNAs), and microRNAs (miRNAs) are carried by exosomes to cells in remote locations, like a message in a bottle. Because they can protect encapsulated small RNAs from ribonucleases (RNases) in body fluid, exosomes represent ideal carriers for nucleic acid drugs. In addition, because exosomes are constructed from self components, they are predicted to have low antigenicity and toxicity, extremely important properties for carriers used in drug delivery. This article describes a protocol for using exosomes as carriers for RNA drug delivery systems.