[1] Univ Tokyo, Inst Med Sci, Ctr Stem Cell Biol & Regenerat Med, Minato Ku, Tokyo 1088639, Japan
[2] Juntendo Univ, Fac Med, Dept Coloproctol Surg, Tokyo, Japan
[3] Univ Tokyo, Inst Med Sci, Ctr Stem Cell Biol & Regenerat Med, Dept Stem Cell Dynam, Tokyo 1088639, Japan
[4] Tohoku Univ, Grad Sch Med, United Ctr Adv Res & Translat Med, Sendai, Miyagi 980, Japan
[5] Juntendo Univ, Sch Med, Atopy Allergy Ctr, Tokyo 113, Japan