Isolation and Characterization of Infrapatellar ADSCs

Infrapatellar fat pad in the knee joint cavity of New Zealand white rabbits (1 month) was extracted according as established previously [14 (link)]. In brief, fat were cut into small pieces (~ 2 mm) and enzymatically dissociated using a 0.05% collagenase II solution (Worthington, Columbus, OH, USA) for 30 min at 37 °C. After neutralization of the enzyme, cells were centrifuged at 500×g for 5 min and filtered through a 70-μm nylon mesh (Merck Millipore, Danvers, MA). ADSCs at passage 3 were used. ADSCs were characterized using flow cytometry with stem cells markers: CD105, CD45, CD73 and CD34. Moreover, ADSCs were characterized based on their adipogenic, osteogenic, and chondrogenic capacities.