Hepatic differentiation of mouse embryonic stem cells in three-dimensional polymer scaffolds.

Embryonic stem cells (ESCs) can have unlimited proliferation potential and the capability to differentiate into almost all types of tissues. The use of ESCs as a novel source of hepatocytes has therefore recently received much attention. To date, however, the efficient and mass differentiation of ESCs into hepatocytes in vitro has been proven to be difficult. In this study, we investigated a three-dimensional (3D) mouse ESC hepatic differentiation system. Cells derived from 5-day-old embryoid bodies were mixed with Matrigel and immediately seeded in a biodegradable polymer scaffold composed of poly-l-lactic acid and polyglycolic acid. Exogenous growth factors and hormones were added sequentially for 20 days to promote hepatic histogenesis. The system enabled spontaneous spheroid formation and mass cultivation of embryoid body-derived cells. The 3D differentiated hepatocyte-like cells were able to express several liver-specific markers and proteins, secrete albumin, store glycogen, and allow the uptake of low-density lipoproteins. These findings suggest that this supportive 3D environment with appropriate inducing factors could provide mouse ESC-derived cells with an environment closely mimicking that of hepatogenesis in vivo.