The dECM insert holder assembly was composed of an insert holder (Figure The growth medium was refreshed every 2-3 days over 7 days of proliferation in a T75 flask. The flask was then rinsed twice with 5 mL PBS prior to adding 5 mL of 37 °C trypsin (25200056, Thermo Fisher, Pittsburgh, PA, USA) and incubated at 37 °C for 10 min.