Evidence for immune activation in patients with residual hepatitis C virus RNA long after successful treatment with IFN and ribavirin.

Low-level hepatitis C virus (HCV) RNA may persist in PBMCs after successful treatment of chronic hepatitis C, but the consequences of this phenomenon are unclear. Forty-nine patients who achieved a sustained virological response (SVR) after pegylated IFN and ribavirin therapy were analysed 52-66 months after the SVR. HCV RNA was detected in PBMCs from 18 patients (47.4 %), and PBMCs in two patients stained positive for non-structural protein 3 (NS3). Quantification of various cytokine and chemokine transcripts in PBMCs revealed that levels of IL-6, IL-8, IL-12, TNF-α and macrophage inflammatory protein 1β were significantly higher in HCV-positive patients than in HCV-negative individuals. In conclusion, persistence of HCV RNA in PBMCs of patients with a SVR appears to be associated with immune activation.