Detection of hepatitis C virus RNA in serum and peripheral blood mononuclear cells.

Hepatitis C virus (HCV) RNA is the most reliable marker of HCV infection. However, because of HCV genome heterogeneity and the procedures used to isolate the viral genome and to perform the amplification steps, results do not accurately reflect the actual rate of HCV infection. In this study, several isolation procedures and sets of primers to perform PCR were compared for the detection of HCV-RNA in serum and peripheral blood mononuclear cells (PBMC) of patients with HCV infection. It was found that the extraction with guanidinium isothiocyanate prior to cDNA synthesis followed by PCR amplification of the 5'-UTR region gave the best results in serum and PBMC. The presence of the viral genome in PBMC is a frequent event during HCV infection and this has important consequences for the understanding of the viral pathogenesis.