Table 3.

Comparison of cell membrane vesicles and extracellular vesicles.

	Cell membrane vesicles	Extracellular vesicles
Source	Extrusion of cell membrane	Secretion by cells
Size (diameter)	100–400 nm	20 nm–2 μm
Separation	Separation process of membrane and intramembrane mixture	Separation of extracellular vesicles and source cells
Cargo loading	Nanoparticles or direct loading of drugs	Drugs are usually loaded directly.
Source of cells	Red blood cell, white blood cell, platelet, cancer cell, fibroblast, bacterial, etc.	Dendritic cell, stem cell, macrophage, cancer cell, HEK293 cell, bacterial outer membrane vesicles, etc.
Advantages	Long-term circulation; Good biological barrier permeability; Efficient cell fusion; Large production.	Low immunogenicity, non-cytotoxicity, high biocompatibility; Intrinsic tumor targeting; Efficient cellular uptake.