Elevated levels of interleukin-8 in serum are associated with hepatitis C virus infection and resistance to interferon therapy

Hepatitis C virus (HCV), a major cause of liver disease worldwide, is frequ ently resistant to the antiviral alpha interferon (IFN). We have recently f ound that the HCV NS5A protein induces expression of the proinflammatory ch emokine IL-8 to partially inhibit the antiviral actions of IFN in vitro. To extend these observations, in the present study we examined the relationsh ip between levels of IL-8 in serum, HCV infection, and biochemical response to IFN therapy. Levels of IL-8 were significantly elevated in 132 HCV-infe cted patients compared to levels in 32 normal healthy subjects and were als o significantly higher in patients who did not respond to IFN therapy than in patients who did respond to therapy. This study suggests that HCV-induce d changes in levels of chemokine and cytokine expression may be involved in HCV antiviral resistance, persistence, and pathogenesis.