Fig. 2

Spontaneous spheroid formation from oral mucosa- and skin-derived cells. a Phase-contrast images of spheroids. In medium containing serum, oral mucosa-derived cells and skin-derived cells spontaneously aggregate and form compact multicellular spheroids within 24 h after cell seeding. b The size of spheroids from oral mucosa- and skin-derived cells. The difference was significant at 120 h; n = 10. c The number of spheroids from oral mucosa- and skin-derived cells. A significant difference was observed only at 120 h; n = 10. d The effect of additives on the size of spheroids. Spheroid size was significantly larger in medium containing bFGF, EGF, and B27 supplement than in medium without these additives; n = 20. e The effect of additives on the number of spheroids. A larger number of spheroids were observed in medium containing bFGF, EGF, and B27 supplement than in medium without these additives; n = 6. Scale bars = 100 μm. The data are presented as the mean ± SEM; *p < 0.05; ***p < 0.001