Peripheral mononuclear cells of haemophiliacs with chronic liver disease are infected with replicating hepatitis C virus.

Most haemophiliacs treated with non-virally inactivated concentrates have been infected with the hepatitis C virus (HCV). 19/21 (90%) patients with HCV antibody were found to have HCV RNA in their serum and in 16 of these it was also detected in peripheral blood mononuclear cells (PBMC). We used specific primers to detect the negative (replicative) strand of this single positively stranded virus. The negative strand was detected in the serum or PBMC of 16 patients indicating active replication outside the liver. The detection of replicating HCV RNA in the cells of HIV negative haemophiliacs could explain at least some of the immunological abnormalities previously reported in these patients and attributed to clotting factor concentrates.