Figure 1

From: Engineering exosomes as refined biological nanoplatforms for drug delivery

Figure 1

Exosome generation, secretion and cargo transfer from the donor cells to the recipient cells. Exosome are small membrane vesicles secreted by most cell types. Internal vesicles form by the inward budding of the cellular compartments known as multivesicular body (MVB). When MVB fuse with the plasma membrane, these internal vesicles are released as exosomes, which can transfer the DNA, RNA and proteins to the distant recipient cells, and influent various aspects of cell behavior and physiology. The inset shows a typical ultracentrifugation protocol. In consecutive rounds of centrifugation and pouring off, the RCF (g) and the centrifugation time are increased to pellet smaller particles. After first 200×g and 2000×g centrifugations, pellets that contain dead cells and cell debris are discarded, and the supernatant is kept for the next step. In contrast, after the 100 000×g centrifugations, pellets (containing EVs) are kept, and supernatants are discarded. The pellets are resuspended in phosphate buffered saline (PBS) for further analysis.