HEPATITIS-C VIRUS-RNAS IN PLASMA AND IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS OF HEMOPHILIACS WITH CHRONIC HEPATITIS-C - EVIDENCE FOR VIRAL REPLICATION IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS

Hemophiliacs who have been exposed to unheated and/or dry heated poole d clotting factor concentrates are at high risk of chronic hepatitis C . Although the mechanism and site of hepatitis C virus (HCV) replicati on are not yet known, HCV is thought to replicate through a complement ary negative RNA strand, as has been shown for flaviviruses. The detec tion of negative RNA strands has therefore been regarded as a marker o f replication. We investigated the prevalence of HCV-RNA and of negati ve HCV-RNA strands in peripheral blood mononuclear cells (PBMC) and pl asma of hemophiliacs. Forty-three of 47 patients studied (91%) had ant i-HCV antibodies and in 36 patients HCV-RNA was detectable in PBMC. In one group of 20 patients negative HCV-RNA strands were present in PBM C and 10 of these patients also had negative HCV-RNA strands in plasma . In another group of nine patients HCV-RNA was detected in PBMC, alth ough cDNA synthesis was carried out in the absence of primers. Only in two of these nine patients negative and positive HCV-RNA strands were demonstrated specifically in PBMC using a modified reverse transcript ion step. If the presence of negative HCV-RNA strands can be considere d as marker of viral replication, the findings indicate that HCV can r eplicate in PBMC. Furthermore, in certain patients it is impossible to use the currently available technique to detect selectively positive or negative HCV-RNA strands. (C) 1994 Wiley-Liss, Inc.