Quasispecies of hepatitis C virus in serum and in three different parts ofthe liver of patients with chronic hepatitis

Hepatitis C virus (HCV) has been known to infect hosts as a quasispecies. S everal reports have shown this using serum samples, but there is little inf ormation about quasispecies in the liver. In this study, we evaluated quasi species in serum and in 3 different parts of the liver in 8 patients with v arying severity of chronic hepatitis C by calculating nucleotide diversity, entropy, type of substitution and by phylogenetic analysis. Nucleotide div ersity of HCV was different in each sample and ranged from 0.37% +/- 0.31% to 4.10% +/- 1.06%. However, the degree of HCV diversity in serum correlate d with that in the liver in each patient (P <.01). Common HCV clones were f ound both in serum and liver samples in all 6 noncirrhotic patients, but al l serum clones were different from the clones from the 2 cirrhotic livers. Phylogenetic analysis showed that the degree of genetic diversity of HCV am ong the 3 liver samples was significantly high in the 4 patients with fibro sis. These genetic compartmentalizations of HCV did not depend on the type of substitution or the viral load of each liver sample. HCV quasispecies wi thin the liver may be closely related to the viral life cycle and the patho genesis of persistent infection of HCV.