Detection of replicative form of hepatitis C virus RNA in peripheral blood mononuclear cells

Paired samples of plasma and peripheral blood mononuclear cells (PBMC) from 7 patients with posttransfusion hepatitis C were collected and studied for the presence of replicative forms of hepatitis C virus (HCV). RNA was extracted and tested for both positive and negative strands of HCV RNA by polymerase chain reaction. Positive-strand RNA of HCV was found in both plasma and PBMC of all 7 patients. However, negative-strand RNA was found in PBMC of 3 patients while none was found in the plasma. Levels of negative-strand RNA were about 10-100 times less than those of positive-strand RNA by semiquantification with serial dilution of viral cDNA. The results suggest that active infection and replication of HCV in PBMC is present in patients with posttransfusion hepatitis C and implicate the extrahepatic infection of HCV.