However, such molecules should be related to viral

persistence and should be good candidates in the development of new therapies against HCV. The classification of HCV genotypes has been established, and genotype determination has become easier with recent improvements in nucleotide sequencing technology. A new genotype may potentially be found in areas where medical supplies are insufficient. Genetic variability of the virus affects liver cell metabolism and influences the outcome of IFN therapy. Further precise analysis of nucleotide and amino acid sequences of the virus and association with human genome polymorphisms will give us the opportunity to better understand phenomena caused by host and virus interactions. Kinase Inhibitor high throughput screening This work was supported in part by Grants-in-Aid for scientific research and development from the Ministry of Health, Labor and Welfare and Ministry of Education, Culture Sports Science and Technology, Government of Japan. We thank Dr Keiko Arataki of Hiroshima Memorial Hospital and Sakura Akamatsu for their assistance. “
“The origin of fibrogenic cells in liver fibrosis remains controversial. We assessed the emerging concept that hepatocytes contribute to production STAT inhibitor of extracellular matrix (ECM) in liver fibrosis through epithelial-mesenchymal transition (EMT). We bred triple transgenic

mice expressing ROSA26 stop β-galactosidase (β-gal), albumin Cre, and collagen α1(I) green fluorescent protein (GFP), in which hepatocyte-derived cells are permanently labeled by β-gal and type I collagen-expressing

cells are labeled by GFP. We induced liver fibrosis by repetitive carbon tetrachloride (CCl4) injections. Liver sections and isolated cells were evaluated for GFP and β-gal as well as expression of α-smooth muscle actin (α-SMA) and fibroblast-specific protein 1 (FSP-1). Upon stimulation with transforming growth factor β-1, cultured hepatocytes isolated from untreated liver expressed both GFP and β-gal with a fibroblast-like morphological 上海皓元医药股份有限公司 change but lacked expression of other mesenchymal markers. Cells from CCl4-treated livers never showed double-positivity for GFP and β-gal. All β-gal-positive cells exhibited abundant cytoplasm, a typical morphology of hepatocytes, and expressed none of the mesenchymal markers including α-SMA, FSP-1, desmin, and vimentin. In liver sections of CCl4-treated mice, GFP-positive areas were coincident with fibrotic septa and never overlapped X-gal-positive areas. Conclusion: Type I collagen-producing cells do not originate from hepatocytes. Hepatocytes in vivo neither acquire mesenchymal marker expression nor exhibit a morphological change clearly distinguishable from normal hepatocytes. Our results strongly challenge the concept that hepatocytes in vivo acquire a mesenchymal phenotype through EMT to produce the ECM in liver fibrosis. (HEPATOLOGY 2009.