Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Nov 14, 2006; 12(42): 6818-6827
Published online Nov 14, 2006. doi: 10.3748/wjg.v12.i42.6818
Promoted differentiation of cynomolgus monkey ES cells into hepatocyte-like cells by co-culture with mouse fetal liver-derived cells
Ko Saito, Masahide Yoshikawa, Yukiteru Ouji, Kei Moriya, Mariko Nishiofuku, Shigehiko Ueda, Noriko Hayashi, Shigeaki Ishizaka, Hiroshi Fukui
Ko Saito, Kei Moriya, Mariko Nishiofuku, Shigehiko Ueda, Hiroshi Fukui, Department of Gastroenterology and Hepatology, Nara Medical University, Kashihara, Nara, Japan
Masahide Yoshikawa, Yukiteru Ouji, Noriko Hayashi, Shigeaki Ishizaka, Division of Developmental Biology, Department of Parasitology, Nara Medical University, Kashihara, Nara, Japan
Author contributions: All authors contributed equally to the work.
Correspondence to: Masahide Yoshikawa, Division of Developmental Biology, Department of Parasitology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan. myoshika@naramed-u.ac.jp
Telephone: +81-744-298857 Fax: +81-744-247122
Received: July 24, 2006
Revised: September 5, 2006
Accepted: September 12, 2006
Published online: November 14, 2006
Abstract

AIM: To explore whether a co-culture of cynomolgus monkey embryonic stem (cES) cells with embryonic liver cells could promote their differentiation into hepatocytes.

METHODS: Mouse fetal liver-derived cells (MFLCs) were prepared as adherent cells from mouse embryos on embryonic d (ED) 14, after which undifferentiated cES cells were co-cultured with MFLCs. The induction of cES cells along a hepatic lineage was examined in MFLC-assisted differentiation, spontaneous differentiation, and growth factors (GF) and chemicals-induced differentiations (GF-induced differentiation) using retinoic acid, leukemia inhibitory factor (LIF), FGF2, FGF4, hepatocyte growth factor (HGF), oncostatin M (OSM), and dexamethasone.

RESULTS: The mRNA expression of α-fetoprotein, albumin (ALB), α-1-antitrypsin, and hepatocyte nuclear factor 4α was observed earlier in the differentiating cES cells co-cultured with MFLCs, as compared to cES cells undergoing spontaneous differentiation and those subjected to GF-induced differentiation. The expression of cytochrome P450 7a1, a possible marker for embryonic endoderm-derived mature hepatocytes, was only observed in cES cells that had differentiated in a co-culture with MFLCs. Further, the disappearance of Oct3/4, a representative marker of an undifferentiated state, was noted in cells co-cultured with MFLCs, but not in those undergoing spontaneous or GF-induced differentiation. Immunocytochemical analysis revealed an increased ratio of ALB-immunopositive cells among cES cells co-cultured with MFLCs, while glycogen storage and urea synthesis were also demonstrated.

CONCLUSION: MFLCs showed an ability to induce cES cells to differentiate toward hepatocytes. The co-culture system with MFLCs is a useful method for induction of hepatocyte-like cells from undifferentiated cES cells.

Keywords: Primate embryonic stem cells; Fetal liver; Hepatic differentiation; Co-culture