Detection of replicative intermediates of viral RNA in peripheral blood mononuclear cells from chronic hepatitis C virus carriers.

Clinical and experimental evidence suggests the possible existence of one or more extrahepatic sites of HCV infection. In order to demonstrate the "in vivo" infection of lymphoid cells by HCV, we applied a nested PCR to total cytoplasmic RNA extracted from fresh or cultured peripheral blood mononuclear cells (PBMCs) of HCV chronically infected patients, using primers derived from the highly conserved 5' untranslated region of the HCV genome. The presence of virions in PBMCs occurs frequently, if not always, and is often accompanied by active viral replication. Moreover, the appearance of replicative intermediates after stimulation of cellular growth with mitogens suggests that latent genomes could undergo replication upon cellular activation and/or proliferation.