Table 1.

Release testing of SCEV

Assay	Results
Sterility	Negative
Endotoxin	< 0.5 EU/kg body weight
Mycoplasma	Negative
Particle concentration per mL	3.74 × 1011 ± 9.28 × 109
Particle mode size: between 50 and 200 nm	137.0
Protein content	0.48 mg/mL
Characterization by flow cytometry analysis	CD81 90.5% CD63 95.5%

EU: Endotoxin units, CD81 and CD63 are tetraspanins known to be enriched in exosomal membranes; SCEV: Schwann cell extracellular vesicles.