Toll-like receptor activated human and murine hepatic stellate cells are potent regulators of hepatitis C virus replication

作者:Wang, Bo; Trippler, Martin; Pei, Rongjuan; Lu, Mengji; Broering, Ruth; Gerken, Guido; Schlaak, Joerg F.*
来源:Journal of Hepatology, 2009, 51(6): 1037-1045.
DOI:10.1016/j.jhep.2009.06.020

摘要

Background/Aims: While hepatic stellate cells (HSC) are known to be key mediators of liver fibrosis, only little is known about their functional role in the innate immune system of the liver. @@@ Methods:To address this question, murine HSC were isolated from livers of C57BL/6J mice and human HSC were isolated from liver samples obtained from resections and liver explants. HSC were stimulated with Toll-like receptor (TLR) 1-9 ligands for 20 h. Supernatants were harvested and used in virus protection assays (encephalomyocarditis virus, EMCV) as well as in human and murine hepatitis C virus (HCV) replicon systems. Expression of interferon (IFN), retinoic acid-inducible gene-l (RIG-1), and interferon-stimulated genes (ISGs) was assessed by quantitative reverse transcription polymerase chain reaction. @@@ Results: While all TLRs were detectable in HSC, in murine HSC only TLR 3 and -4 agonists could induce cytokines that had an antiviral effect upon EMCV and HCV replication. IFN-beta was the main cytokine mediating the antiviral activity of TLR 3-stimulated HSC whereas other cytokines of undefined nature were involved in TLR 4-mediated antiviral effects. In human HSC, only TLR 3 stimulation led to production of antiviral cytokines. The antiviral effect was related to the up-regulation of ISGs and RIG-I in target cells. @@@ Conclusions: These data demonstrate that murine and human HSC have as yet unrecognized antiviral properties when activated through the TLR-system and TLR 3/HCV in particular. This sheds new light on their role in the innate immune system of the liver and their participation in the control of HCV replication.