(622n) Hepatic Differentiation of Controlled-Size Embryonic Bodies Derived By Inverted Colloidal Crystal Scaffolds

Embryonic stem (ES) cells hold promising potential as a renewable cell source for tissue regeneration and cell-based therapy. ES cell-derived specific cell lineages were strongly influenced by the control of the microenvironment, such as the size of embryoid bodies (EBs). Several microscale engineering approaches have been developed to control the size and shape of EBs and to direct embryonic stem cell fate for cardiogenesis and neurogenesis. However, desirable microenvironment for directed differentiation of ES cells to hepatocyte-like cells are still unknown. Here, we used Inverted Colloidal Crystal with highly uniform porous structure to regulate EBs and differentiate them into hepatic fate. Murine ES (mES) cells were aggregated within the scaffolds, and their aggregate sizes were controlled by varying diameters of pores in scaffold (90 µm, 170 µm, 200 µm, 270 µm and 400 µm). Differentiation of murine ES cells into early hepatocytes was assessed by analyzing gene expression. We found that hepatic differentiation of ES cells were strongly regulated by the EB size, showing that EB equals to and larger than 179.6±26.9 µm maintained the functionality to differentiated to specific lineage and with the diameter of 201.7± 29.6 µm induced highest yield of hepatic differentiation where the optimal pore size of scaffolds is 270 µm.