Tissue-derived extracellular vesicles: Isolation, purification, and multiple roles in normal and tumor tissues

Extracellular vesicles (EVs) are particles released from cells, and their lipid bilayer membrane encloses large amounts of bioactive molecules that endow EVs with intercellular or inter-tissue communicational abilities. Tissue-derived extracellular vesicles (Ti-EVs) are EVs directly separated from the interstitial space of tissue. They could better reflect the actual physiological or pathological state of the tissue microenvironment compared with cell line-derived EVs and biofluid EVs, indicating their potential roles in elucidating the underlying mechanism of pathogenesis and guiding the diagnosis, therapeutic targeting, and cell-free treatment of diseases. However, there have been a relatively limited number of investigations of Ti-EVs. In this review, we have summarized general procedures for Ti-EVs isolation, as well as some caveats with respect to operations after the isolation step, such as purification and storage. In addition, we have also briefly concluded the current research trends on EVs from various normal and tumor tissues, aiming to cast new light on the future research direction of Ti-EVs.

Automated summary

Extracellular vesicles (EVs) released from cells have intercellular or inter-tissue communication abilities due to the bioactive molecules enclosed in their lipid bilayer membrane. Tissue-derived extracellular vesicles (Ti-EVs) directly isolated from the interstitial space of tissue can better reflect the physiological or pathological state of the tissue microenvironment. This review summarizes the isolation procedures of Ti-EVs and discusses their potential roles in understanding pathogenesis, guiding disease diagnosis and therapy, and exploring cell-free treatments.