Detection of genomic- and minus-strand of hepatitis C virus RNA in the liver of chronic hepatitis C patients by strand-specific semiquantitative reverse-transcriptase polymerase chain reaction.

Studies aimed at correlating the intrahepatic hepatitis C virus (HCV)-RNA level and anatomo-clinical features have been difficult because of sensitivity and specificity shortcomings of available techniques. We titered the genomic- and minus-strand HCV RNAs by a strand-specific, semiquantitative, genotype-independent reverse-transcriptase polymerase chain reaction (RT-PCR) in the liver tissue of 61 patients with chronic hepatitis C. Findings were correlated with the levels of HCV RNA in the serum, the HCV genotype, the expression of intrahepatic HCV antigens, the histological activity (using separate scores for the lobular and the portal/periportal necroinflammatory activity and for the fibrosis), and the response to interferon alfa (IFN-alpha) treatment. Genomic- and minus-strand HCV RNA were detected in 59 and 57 liver specimens, respectively. The HCV-RNA level in the serum correlated with the genomic-strand, but not with the minus-strand, HCV-RNA titer in the liver. No correlations were found between either strand of the intrahepatic HCV RNA and the level of expression of HCV antigens in the liver, or with the grading/staging of the underlying liver disease. The response to IFN-alpha treatment could be predicted by the serum HCV-RNA level and genotype, but not by the intrahepatic level of genomic- or minus-strand HCV RNA. These results suggest that, although the detection of the minus-strand HCV RNA reliably identifies the presence of replicating HCV in its target organ, the quantitative measurement of viremia remains the clinically meaningful "golden standard" for assessing the level of HCV replication.