Basic Research
Copyright ©2008 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. May 7, 2008; 14(17): 2740-2747
Published online May 7, 2008. doi: 10.3748/wjg.14.2740
Hepatic reconstruction from fetal porcine liver cells using a radial flow bioreactor
Yuji Ishii, Ryota Saito, Hideki Marushima, Ryusuke Ito, Taro Sakamoto, Katsuhiko Yanaga
Yuji Ishii, Ryota Saito, Hideki Marushima, Ryusuke Ito, Taro Sakamoto, Katsuhiko Yanaga, Department of Surgery, the Jikei University School of Medicine, Tokyo 105-8461, Japan
Author contributions: Saito R, Marushima H, Ito R, Sakamoto T, and Yanaga K contributed equally to this work.
Correspondence to: Yuji Ishii, MD, PhD, Department of Surgery, the Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan. yujiyunayuta@jikei.ac.jp
Telephone: + 81-3-34331111
Fax: + 81-3-54724140
Received: October 11, 2007
Revised: February 25, 2008
Published online: May 7, 2008
Abstract

AIM: To examine the efficacy of the radial flow bioreactor (RFB) as an extracorporeal bioartificial liver (BAL) and the reconstruction of liver organoids using embryonic pig liver cells.

METHODS: We reconstructed the liver organoids using embryonic porcine liver cells in the RFB. We also determined the gestational time window for the optimum growth of embryonic porcine liver cells. Five weeks of gestation was designated as embryonic day (E) 35 and 8 wk of gestation was designated as E56. These cells were cultured for one week before morphological and functional examinations. Moreover, the efficacy of pulsed administration of a high concentration hepatocyte growth factor (HGF) was examined.

RESULTS: Both cell growth and function were excellent after harvesting on E35. The pulsed administration of a high concentration of HGF promoted the differentiation and maturation of these fetal hepatic cells. Microscopic examination of organoids in the RFB revealed palisading and showed that bile duct-like structures were well developed, indicating that the organoids were mini livers. Transmission electron microscopy revealed microvilli on the luminal surfaces of bile duct-like structures and junctional complexes, which form the basis of the cytoskeleton of epithelial tissues. Furthermore, strong expression of connexin (Cx) 32, which is the main protein of hepatocyte gap junctions, was observed. With respect to liver function, ammonia detoxification and urea synthesis were shown to be performed effectively.

CONCLUSION: Our system can potentially be applied in the fields of BAL and transplantation medicine.

Keywords: Liver organoid; Radial flow bioreactor; Bioartificial liver; Fetal porcine liver; Hepatocyte growth factor