Upregulation of endogenous intrahepatic interferon stimulated genes during chronic hepatitis C virus infection

The success of interferon-alpha and ribavirin combination therapy for the treatmeht of chronic hepatitis C viral infection differs between patients. In an attempt to identify predictors of host response to therapy, the levels of mRNA for interferon (IFN) stimulated genes: MxA, PKR, 2'5' OAS, ISG15, and interleukin 8 (IL-8), were examined in liver by real-time RT-PCR prior to commencement of therapy, The levels of intrahepatic classical IFN stimulated genes, but not IL-8, in chronic HCV disease (n=44) were found to be significantly upregulated (P<0.001) compared to the control cohort (n=12). The genotype of the infecting HCV strain did not influence IFN stimulated gene expression. These results suggest that the endogenous type 1 IFN antiviral effector pathway is broadly activated during chronic HCV disease, although the levels of mRNA for any of the IFN-stimulated genes tested did not predict the outcome of combination therapy.