Liver Research Project Center

Hiroshima-shi, Japan

Liver Research Project Center

Hiroshima-shi, Japan
SEARCH FILTERS
Time filter
Source Type

Chayama K.,Hiroshima University | Chayama K.,Liver Research Project Center | Hayes C.N.,Hiroshima University | Hayes C.N.,Liver Research Project Center | And 8 more authors.
Journal of Gastroenterology and Hepatology (Australia) | Year: 2011

Human hepatitis B virus (HBV) and hepatitis C virus (HCV) infect only chimpanzees and humans. Analysis of both viruses has long been hampered by the absence of a small animal model. The recent development of human hepatocyte chimeric mice has enabled us to carry out studies on viral replication and cellular changes induced by replication of human hepatitis viruses. Various therapeutic agents have also been tested using this model. In the present review, we summarize published studies using chimeric mice and discuss the merits and shortcomings of this model. © 2010 Journal of Gastroenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd.


Chayama K.,Hiroshima University | Chayama K.,Liver Research Project Center | Hayes C.N.,Hiroshima University | Hayes C.N.,Liver Research Project Center
Journal of Gastroenterology and Hepatology (Australia) | Year: 2011

As an RNA virus, hepatitis C virus (HCV) shows a characteristically high level of nucleotide diversity. Accumulation of nucleotide substitutions in the virus has resulted in diversification into quasispecies, subtypes and distinct genotypes. Pathobiological studies linking nucleotide and amino acid sequences with clinical findings have identified relationships between certain genotypes and characteristic biological properties. Genotype 3 HCV infection was found to be associated with a high level of liver steatosis. Genotypes 1 and 4 were found to be more resistant to interferon (IFN) based therapies than genotypes 2 and 3. Studies of genotype 1 sequences obtained from patients treated with IFN have identified a relationship between favorable response to interferon therapy and amino acid substitutions in the NS5A region (interferon response determining region; ISDR). Further studies have identified a relationship between the effect of IFN therapy and other regions of the NS5A protein. More recently, a relationship has been found between poor response to peg-IFN plus ribavirin combination therapy and substitutions at amino acid 70 and 91 in the core protein. Furthermore, a correlation between human genetic variation in the IL28B (IFN-lamda 3) locus and core amino acid substitutions has been characterized.In this review we briefly summarize the discovery, classification and nomenclature of HCV genotypes and subtypes. We also discuss amino acid substitutions within specific regions that have been reported to be associated with outcome of IFN and peg-IFN plus ribavirin combination therapy. © 2011 Journal of Gastroenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd.

Loading Liver Research Project Center collaborators
Loading Liver Research Project Center collaborators