Development of an in vitro Model to Study Hepatitis C virus-induced Fibrosis

Abstract

Aim: To investigate the mechanism of liver fibrosis in chronic hepatitis C virus (HCV) infection we developed an in vitro model. Methods: Huh7 cells were transfected with HCV (JFH1 or Jc1) or sub-genomic replicons and expression of pro-fibrotic cytokines determined by qPCR. Media from infected cells was transferred onto LX2 cells or primary rat stellate cells and expression of pro-fibrotic genes measured by qPCR. Results: Replication competent HCV, but not sub-genomic replicons, induced expression of TGF-β1 and CTGF. Supernatant from infected cells induced α-SMA and COL1A1 expression and stellate cell migration, confirming functional activation. Conclusion: Infected cells produce pro-fibrogenic cytokines TGF-β1 and CTGF and activate stellate cells. This mechanism could be targeted to prevent or treat HCV-induced fibrosis.

Plain language summary

We developed a new laboratory model to study why people with hepatitis C develop liver damage. We plan to use this model to develop new treatments. We found that cells infected with whole hepatitis C virus release chemicals that cause inflammation in the liver, which can lead to liver damage and scarring. We confirmed that these chemicals act on other cells in the liver (‘stellate cells’), causing them to become active and to move around. Active stellate cells are known to cause liver damage and scarring, explaining why hepatitis C causes liver damage. Our results provide new ideas to develop drugs that can prevent liver damage in people with hepatitis C.

Keywords:

• cirrhosis
• hepatitis C virus
• in vitro models
• liver fibrosis
• viral pathogenesis

Author contributions

All authors have read and agree to the published version of the manuscript. Conceptualization: B Rauff, MW Douglas and J George. Methodology: B Rauff, M Ramezani-Moghadam and ESE Tay. Formal analysis: B Rauff and MW Douglas. Resources: J George. Writing – original draft preparation: B Rauff. Writing – review and editing: MW Douglas and J George. Visualization: B Rauff and MW Douglas. Supervision: MW Douglas and J George. Funding acquisition: B Rauff, MW Douglas and J George.

Financial disclosure

This study was supported by Program and Project Grants from the National Health and Medical Research Council (NHMRC) of Australia (nos. 1003767, 1047417 and 1053206) and the Robert W Storr bequest to the Sydney Medical Foundation, University of Sydney. B Rauff was supported by an International Postgraduate Research Scholarship (IPRS) funded by the Australian Commonwealth Government and an Australian Postgraduate Award (APA) funded by the University of Sydney, Australia. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Competing interests disclosure

The authors have no competing interests or relevant affiliations with any organization or entity with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Writing disclosure

No writing assistance was utilized in the production of this manuscript.