Interleukin-1 inhibits hepatitis C virus subgenomic RNA replication by activation of extracellular regulated kinase pathway.

Interleukin-1 (IL-1) plays an important role in the inflammatory process. Some studies have demonstrated that IL-1 production was impaired in patients with chronic infections of hepatitis C virus (HCV), implying that IL-1 may play a role in viral clearance. Using an HCV subgenomic replicon cell line, we demonstrate that IL-1 can effectively inhibit HCV subgenomic RNA replication and viral protein expression, suggesting that IL-1 has direct antiviral activity. The inhibitory effect is associated with the extracellular regulatory kinase (ERK) activation. In addition, we also show that IL-1 can induce one of the interferon-stimulated genes (ISGs), 1-8U, which exhibits antiviral activity. However, it has no effect on the other ISG, 6-16, suggesting that IL-1 induces novel antiviral pathways within a cell.