Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Aug 14, 2006; 12(30): 4859-4865
Published online Aug 14, 2006. doi: 10.3748/wjg.v12.i30.4859
Augmenter of liver regeneration promotes hepatocyte proliferation induced by Kupffer cells
Chun-Ping Wang, Lin Zhou, Shu-Hui Su, Yan Chen, Yin-Ying Lu, Fei Wang, Hong-Jun Jia, Yong-Yi Feng, Yong-Ping Yang
Chun-Ping Wang, Lin Zhou, Shu-Hui Su, Yan Chen, Yin-Ying Lu, Fei Wang, Hong-Jun Jia, Yong-Yi Feng, Yong-Ping Yang, Department of Gastroenterology, 302 Hospital of Chinese PLA, Beijing 100039, China
Author contributions: All authors contributed equally to the work.
Supported by the National High Technology Research and Development Program of China (863 Program), No. 2003 AA208106; Medical Outstanding Talent Foundation of the Army, No. 04J020
Correspondence to: Yong-Ping Yang, MD, PhD, Department of Gastroenterology, 302 Hospital of Chinese PLA, 100 Xisihuan Middle Road, Beijing 100039, China. yongpingyang@hotmail.com
Telephone: +86-10-66933429 Fax: +86-10-63879193
Received: March 16, 2006
Revised: April 1, 2006
Accepted: April 21, 2006
Published online: August 14, 2006
Abstract

AIM: To observe the effects of augmenter of liver regeneration (ALR) on Kupffer cells and to determine whether ALR promotes hepatocyte proliferation induced by Kupffer cells.

METHODS: Kupffer cells and hepatocytes were cultured in vitro and various concentrations of recombinant rat ALR (rrALR) were added. 3H-thymidine, BrdU and 3H-leucine incorporation was determined in cultured Kupffer cells and hepatocytes, in hepatocytes conditioned by Kupffer cells, and in associated medium. rrALR was labeled by iodination and used to determine its binding activity by Scatchard analysis in Kupffer cells and primarily cultured rat hepatocytes.

RESULTS: rrALR stimulated DNA replication in Kupffer cells and protein synthesis both in cells and in medium in a non-concentration-dependent manner. The effect was significant at the concentration of 1 μg/L ALR. However, rrALR had no effect on primarily cultured hepatocytes, when hepatocytes were cultured with the Kupffer cell medium conditioned by ALR, DNA replication and protein synthesis in hepatocytes increased significantly at the concentration of 1 μg/L ALR. When the ALR concentration was increased, its effect on hepatocyte proliferation decreased to the basal level. Scatchard analysis indicated the presence of a single class of high affinity receptors with a dissociation constant (Kd) of 0.883 nmol/L and a maximum binding capacity (Bmax) of 126.1 pmol/g protein in the rat Kupffer cells.

CONCLUSION: ALR can promote hepatocyte pro-liferation induced by Kupffer cells, which is associated with the concentration of ALR, suggesting that Kupffer cells play a dual role in liver regeneration.

Keywords: Liver regeneration; Augmenter of liver regeneration; Kupffer cell