Efficacy of extracellular vesicles derived from mesenchymal stromal cells in regulating senescence: In vitro and in vivo insights

Table 1 The critical quality control points of clinical-grade extracellular vesicles derived from mesenchymal stromal cells

	Parameter	Method	Release criteria
MSCs	Security
	Sterility	BacT/ALERT	Negative
	Endotoxin (EU/mL)	According to Chinese pharmaceutics	< 0.5
	Mycoplasma	qPCR	Negative by qPCR
	Biological activity and characterization
	Cell viability (%)	Trypan blue staining	≥ 90%
	Marker profile	Flow cytometry	CD90, CD105, CD73, CD 44 ≥ 95%; CD45, CD34, CD11b, CD HLA-DR ≤ 2%
	Trilineal differentiation	Osteogenesis, lipogenesis and chondrogenesis	Positive
EVs	Security
	Sterility	BacT/ALERT	Negative
	Endotoxin (EU/mL)	According to Chinese pharmaceutics	< 0.5
	Mycoplasma	qPCR	Negative by qPCR
	Biological activity and characterization
	Morphology	Transmission electron microscopy	Nonagglomerated saucer-like or cup-like structures with clear edges and membrane structure
	Particle size	NanoFCM	Distributed in a range of < 200 nm with a size peak in this range
	Marker protein	Western blotting	Presence of the surface biomarkers (CD9 and CD81) and interior biomarker TSG101; absence of the negative biomarker GM130
	Purity	Triton X-100/NanoFCM	The phospholipid membranes of EVs can be lysed by Triton X-100

MSCs: Mesenchymal stromal cells; qPCR: Quantitative polymerase chain reaction; NanoFCM: Nano flow cytometry; EVs: Extracellular vesicles; TSG101: Tumor susceptibility gene 101.