Wang, Y.; Leaker, B.; Qiao, G.; Sojoodi, M.; Eissa, I. R.; Epstein, E. T.; Eddy, J.; Dimowo, O.; Mullen, A. C.; Lauer, G. M.; Chung, R. T.; Qadan, M.; Lanuti, M.; Fuchs, B. C.; Tanabe, K. K.

Background: Precision-Cut Liver Slices (PCLS) are an ex vivo culture model developed to study hepatic drug metabolism. One of the main benefits of this model is that it retains the structure and cellular composition of the native liver. PCLS also represents a potential model system to study liver fibrosis in a setting that more closely approximates in vivo pathology than in vitro methods. The aim of this study was to assess whether responses to antifibrotic interventions can be detected and quantified with PCLS. Methods: PCLS of 250 m thickness were prepared from four different murine fibrotic liver models: choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD), thioacetamide (TAA), diethylnitrosamine (DEN), and carbon tetrachloride (CCl4). PCLS were treated with 5 M Erlotinib for 72 hours. Histology and gene expression were then compared with in vivo murine experiments and TGF-{beta}1 activated hepatic stellate cells (HSC). These types of PCLS characterization were also evaluated in PCLS from human cirrhotic liver. Results: PCLS viability in culture was stable for 72 hours. Erlotinib treatment significantly inhibited the expression of profibrogenic genes Il6, Col1a1 and Timp1 in PCLS from CDAHFD-induced cirrhotic mice, and Il6, Col1a1 and Tgf-{beta} in PCLS from TAA-induced cirrhotic rats. Erlotinib treatment of PCLS from DEN-induced cirrhotic rats inhibited the expression of Col1a1, Timp1, Tgf-{beta} and Tnf-, which was consistent with the impact of erlotinib on Col1a1 and Tgf-{beta} expression in in vivo DEN-induced cirrhosis. Erlotinib treatment of PCLS from CCl4-induced cirrhosis caused reduced expression of Timp1, Col1a1 and Tgf-{beta}, which was consistent with the effect of erlotinib in in vivo CCl4-induced cirrhosis. In addition, in stellate cells at PCLS from normal mice, TGF-{beta}1 treatment upregulated Acta2 (SMA), while treatment with erlotinib inhibited the expression of Acta2. Similar expression results were observed in TGF-{beta}1 treated HSC cell lines. Expression of MMPs and TIMPs, key regulators of fibrosis progression and regression, were also significantly altered under erlotinib treatment in PCLS. Expression changes under erlotinib treatment were also corroborated with PCLS form human cirrhosis samples. Conclusion: The responses to antifibrotic interventions can be detected and quantified with PCLS at the gene expression level. PCLS from murine cirrhotic livers after treatment with an antifibrotic drug are consistent with those observed in vivo and in vitro. These PCLS characterizations were also observed in PCLS from human cirrhosis. PCLS is an excellent model to assess antifibrotic therapies that is aligned with the principles of Replacement, Reduction and Refinement (3Rs).