Ultrasound cavitation: a reliable non-enzymatic method for adipose-derived mesenchymal stem cell (ADSC) isolation

BACKGROUND: Adipose tissue is known to serve as an abundant and readily accessible source of adipose-derived stem cells (ADSCs) as an alternative to bone marrow. Collagenase is one of the most widely used methods for the isolation of ADSCs from adipose tissue, but it takes a long time, and there are also debates about safety. We propose an ultrasonic cavitation-treated method that can significantly reduce time and avoid the problem of using xenogeneic enzymes in ADSCs isolation. METHODS: ADSCs were isolated from adipose tissue using the enzyme treatment method and the ultrasonic cavitation treatment method. Cell proliferation was measured using cell viability assay. The expression levels of the surface markers of ADSCs were estimated by real-time PCR. After, ADSCs were cultured in chondrogenic, osteogenic, or adipogenic differentiation medium; the differentiation potential of ADCSs was analyzed by Alcian blue, Alizarin Red S, Oil Red O, and real-time PCR. RESULTS: The cells treated with collagenase and ultrasound had similar cell yields and proliferation after isolation. The difference in the expression of surface markers of ADSCs was not statistically significant. ADSCs showed differentiation potential into adipocytes, osteocytes, and chondrocytes, and there was no difference between the enzyme treatment method and the ultrasonic cavitation treatment method. The yield of the ADSC increased in time- and intensity dependently. CONCLUSIONS: Ultrasound certainly serves as a promising method in advancing ADSC isolation technology.