Figure 2.

The flow of the production of drug-loaded EVs. EV-based drug delivery requires the correct choice of source cell type for the specific application, and should ideally be patient-derived to avoid triggering immune response. The therapeutic cargo can include different types of siRNA, miRNA, proteins or small molecule compounds such as curcumin or chemotherapeutics. Drug loading can be carried out either endogenously or exogenously. Endogenous loading is achieved by loading source cell with a therapeutic agent or transfecting source cell with drug-encoding gene which is then released in EVs upon collection. Exogenous loading allows the isolation of EVs before their loading with therapeutic cargo with the help of electroporation, simple incubation, chemical transfection, or other approaches. Importantly, the generation process should meet the quality requirements.