“…Presently remarkable progress has been made in understanding the differentiation of ES cells into neural [Hancock et al, 2000], hematopoietic [Baron, 2001;Perlingeiro et al, 2001;Feng et al, 2005], endothelial , vascular [Sone et al, 2003;Yurugi-Kobayashi et al, 2003;Suzuki et al, 2005], and pancreatic stem/progenitor cells and then various mature cells. However, limited knowledge has been acquired for the differentiation of hepatic progenitor/stem cells, although hepatic differentiation from murine and human ES cells both in vitro and in vivo has been reported in recent studies [Hamazaki et al, 2001;Chinzei et al, 2002;Choi et al, 2002;Ishizaka et al, 2002;Jones et al, 2002;Miyashita et al, 2002;Yamada et al, 2002;Yin et al, 2002;Yamamoto et al, 2003;Kania et al, 2004;Ogawa et al, 2005;Teramoto et al, 2005;Teratani et al, 2005]. These hepatic cells from ES cells expressed some typical markers of mature hepatocytes and showed sufficient functions to rescue experimental liver injury when transplanted in vivo, which raised the hope to generate a transplantable cell source for the treatment of end-stage liver diseases.…”