Fig. 2.

Diagram of the 2D and 3D cultures of 3T3-L1 preadipocytes and those differentiated by adipogenic induction. 2D cultured 3T3-L1 preadipocytes without induction of differentiation (DIF-) were further processed under 2D cell culture and 3D spheroid culture conditions for 7 days. In the 3D spheroid culture, approximately 20,000 cells were placed in each well of a drop culture plate for 3D spheroid generation (Day 0), and the 3D spheroids were then maintained as described in the Materials and Methods section (Panel A). To stimulate adipogenic differentiation (DIF+), the culture was supplemented with 250 nM dexamethasone and 10 nM T3 and with 10 mM troglitazone and 1 mg/ml insulin from Day 1 to Day 3 and from Day 1 to Day 7, respectively. Representative lipid Oil-red O (2D) and BODIPY (3D) stainings, and phase contrast (3D) images are shown in panel B. Scale bar: 100 μm.