Therapeutic application of extracellular vesicles in human diseases

Extracellular vesicles (EVs) are membrane vesicles released or secreted from almost all cell types. EVs are derived from multivesicular bodies or from the plasma membrane and contain a subset of proteins, lipids, and nucleic acids (e.g., DNA, RNA, and microRNA [miRNA]) derived from the parent cell. EVs play important roles in intercellular communication by efficiently transferring the content between cells both locally and systemically. Given their natural ability to transfer cargo to cells, sometimes in a targeted manner, and their apparent lack of immunogenicity, EVs are being engineered for delivery of therapeutic RNAs, DNAs, miRNAs, viral particles, drugs, and even proteins. In addition, many of the therapeutic effects of stem cell treatments are mediated by stem cell-derived EVs, which are safer and potentially more effective than the parental stem cells. Here we provide an overview of the use of EVs for delivery of different therapeutic nucleic acids, viruses, and drugs, as well as the use of therapeutic stem cell-derived EVs.