Figure 4.

Engineering targeting strategies. EV targeting can be manipulated by adding targeting ligands using different strategies. (1) Transfection of the cell with a plasmid to generate the target protein within the cell and thereby facilitate secretion in EVs. (2) Modification of the targeting molecule with a lipid that can be anchored to the membrane of the cells and then indirectly secreted on EVs or (3) by directly adding lipid-linked molecules to the surface of EVs. (4) Covalently linking the targeting agent into the surface of EVs. (5) Using a cationic compound to promote electrostatic interactions with the EVs.