Combining Piezoelectric Stimulation and Extracellular Vesicles for Cartilage Regeneration

Figure 2

Extraction of DS-EVs and validation of its effect on cartilage regeneration (a) classical spherical structure with phospholipid molecular layer observed by DS-EVs in TEM; (b) NTA particle size analysis: the mean diameter of DS-EVs is 130.6 nm; (c) detection of DANCR + SMSC-EVs surface antigens by Western blotting: CD81 and Syntenin-1 positive; (d) detection of DANCR overexpression plasmid transfection efficiency of SMSCs by qPCR: DANCR + SMSCs were successfully constructed, and their DANCR expression level was 273-fold higher than the MOCK group (,); (e) extracellular vesicles fluorescence tracing experiment: the fluorescently labeled DS-EVs entered the chondrocyte matrix after co-culture with articular chondrocytes for 6 h (bar = 20 µm); (f) cell scratch test: After chondrocytes were treated with 60 µg/mL sterile DS-EVs suspension for 24 h, the cell migration ability was significantly enhanced (bar = 500 µm); (g) MTT experiment: chondrocytes were treated with 60 µg/mL sterile DS-EVs suspension for five consecutive days, and the cells were found to proliferate profoundly; (h) Western blotting results: chondrocytes were continuously treated with 60 µg/mL sterile DS-EVs suspension for 3 and 5 days, and the secretion of type II collagen increased; (i) RT-qPCR results: chondrocytes were continuously treated with 60 µg/mL sterile DS-EVs suspension for 3 and 5 days, and the expression levels of COL2A1 increased(, ; , ).

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