Two human iPS cell lines (Fetch and Lollipop) were differentiated into endoderm cells by addition of 100 ng/mL activin A for 5 days, and then into hepatocytes by the addition of 1% DMSO for 7 days. The hepatocytes were then matured by the addition of 10 ng/mL HGF, 20 ng/mL OSM, and 10−7 M DEX for 9 days. For the final 4 days, the cells were cultured in modified Lanford medium alone, without HGF, OSM, or DEX.