[The role of hepatitis C virus core protein on liver fibrogenesis: a study using an in vitro co-culture system].
OBJECTIVE
The study of liver fibrogenesis by hepatitis C virus (HCV) has been limited due to the lack of an efficiency in vitro culture systems. In the present study, we investigated whether or not HCV core protein is directly related to liver fibrogenesis through stimulation of hepatic stellate cells (HSC).


METHODS
Human and rat HSC were isolated and we established an in vitro co-culture system of a stable HepG2-HCV core cell line which was transfected with HCV core gene and primary HSC. We performed immunocytochemical staining and Western and Northern blot analysis in the stimulated HSC by HCV core protein to identify the expression of transforming growth factor beta1 (TGF-beta1), transforming growth factor beta receptor II (TGFbeta R II), alpha-smooth muscle actin (alpha-SMA) and connective tissue growth factor (CTGF). The expression of matrix metalloproteinase-2 (MMP-2) and collagen type I (Col I) in the culture media were measured by zymogram and ELISA, respectively.


RESULTS
The expression of TGF-beta1 and CTGF was significantly higher in the stable HepG2-HCV core cell line than in HepG2 cells. Furthermore, the makers related to fibrosis such as alpha-SMA, TGF-beta1, Col I, TGFRII and MMP-2 were highly expressed in the co-culture of stable HepG2-HCV core with HSC.


CONCLUSIONS
HCV core protein may play a direct role in the fibrogenesis of chronic liver disease with HCV infection.
Shin
Ju Yeop
JY
Department of Internal Medicine, The Catholic University of Korea College of Medicine, 505 Banpo-dong, Seocho-gu, Seoul 137-040, Korea.
Yoon
Seung Kew
SK
Wang
Jin Sang
JS
Hur
Wonhee
W
Ryu
Jong Soon
JS
Bae
Si Hyun
SH
Choi
Jong Young
JY
Yang
Jin Mo
JM
Yang
Se-Hwan
SH
Sung
Young Chul
YC
Chung
Kyu Won
KW
Sun
Hee Sik
HS
D000199:Actins / Q000378:metabolism; D000818:Animals; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D055513:Connective Tissue Growth Factor; D005355:Fibrosis; D018936:Hepatitis C Antigens / Q000502:physiology*; D006801:Humans; D017874:Immediate-Early Proteins / Q000378:metabolism; D015151:Immunoblotting; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D017346:Protein Serine-Threonine Kinases; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D053773:Transforming Growth Factor beta1; D014758:Viral Core Proteins / Q000502:physiology*
D000199:Actins; C526317:CCN2 protein, human; C526316:CCN2 protein, rat; D018936:Hepatitis C Antigens; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D018125:Receptors, Transforming Growth Factor beta; C508960:TGFB1 protein, human; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D014758:Viral Core Proteins; C069130:nucleocapsid protein, Hepatitis C virus; D055513:Connective Tissue Growth Factor; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II