Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Feb 7, 2006; 12(5): 723-730
Published online Feb 7, 2006. doi: 10.3748/wjg.v12.i5.723
GFAP promoter directs lacZ expression specifically in a rat hepatic stellate cell line
Gunter Maubach, Michelle Chin Chia Lim, Chun-Yan Zhang, Lang Zhuo
Gunter Maubach, Michelle Chin Chia Lim, Chun-Yan Zhang, Lang Zhuo, Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, #04-01, 138669, Singapore.
Supported by the Biomedical Research Council and the Institute of Bioengineering and Nanotechnology, the Republic of Singapore
Correspondence to: Dr Lang Zhuo, Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, #04-01, 138669, Singapore. lzhuo@ibn.a-star.edu.sg
Telephone: +65-68247114 Fax: +65-64789080
Received: July 25, 2005
Revised: July 29, 2005
Accepted: August 26, 2005
Published online: February 7, 2006
Abstract

AIM: The GFAP was traditionally considered to be a biomarker for neural glia (mainly astrocytes and non-myelinating Schwann cells). Genetically, a 2.2-kb human GFAP promoter has been successfully used to target astrocytes in vitro and in vivo. More recently, GFAP was also established as one of the several makers for identifying hepatic stellate cells (HSC). In this project, possible application of the same 2.2-kb human GFAP promoter for targeting HSC was investigated.

METHODS: The GFAP-lacZ transgene was transfected into various cell lines (HSC, hepatocyte, and other non-HSC cell types). The transgene expression specificity was determined by X-gal staining of the β-galactosidase activity. And the responsiveness of the transgene was tested with a typical pro-fibrotic cytokine TGF-β1. The expression of endogenous GFAP gene was assessed by real-time RT-PCR, providing a reference for the transgene expression.

RESULTS: The results demonstrated for the first time that the 2.2 kb hGFAP promoter was not only capable of directing HSC-specific expression, but also responding to a known pro-fibrogenic cytokine TGF-β1 by upregulation in a dose- and time-dependent manner, similar to the endogenous GFAP.

CONCLUSION: In conclusion, these findings suggested novel utilities for using the GFAP promoter to specifically manipulate HSC for therapeutic purpose.

Keywords: GFAP; Astrocytes; Hepatic stellate cells; Fibrosis; TGF-β1; LacZ.