[1] Univ Tokyo, Inst Med Sci, Ctr Stem Cell Biol & Regenerat Med, Div Stem Cell Therapy,Minato Ku, Tokyo 1088639, Japan
[2] Japan Sci & Technol Agcy, ERATO, Nakauchi Stem Cell & Organ Regenerat Project, Minato Ku, Tokyo 1088639, Japan
[3] Natl Inst Nat Sci, Natl Inst Physiol Sci, Ctr Genet Anal Behav, Okazaki, Aichi 4448585, Japan
[4] Grad Univ Adv Studies, Sch Life Sci, Okazaki, Aichi 4448585, Japan
[5] Kings Coll Hosp London, Inst Liver Studies, London SE5 9RS, England