Functional impairment of dendritic cells in patients infected with hepatitis C virus genotype 1 who failed peginterferon plus ribavirin therapy.

Although chronic hepatitis C patients have a lower frequency and functions of dendritic cells (DCs) than healthy subjects, little is known about the serial changes in frequency and functions of DCs following anti-viral treatment and the relationship with treatment outcomes. Twenty patients with hepatitis C virus genotype 1 receiving peginterferon (PEG-IFN) and ribavirin for 24 weeks were enrolled. The frequency and functions of DCs were assayed at baseline and 24 weeks post-treatment. Ten sex and age-matched healthy adults served as controls. Nineteen of the 20 chronic hepatitis C patients completed 24 weeks of combination therapy. Fifteen patients achieved rapid virologic response and 12 achieved sustained virologic response (SVR). The baseline frequency of peripheral blood myeloid DCs and plasmacytoid DCs was significantly lower in chronic hepatitis C patients than in healthy controls. In patients who achieved SVR, the frequency of DCs subsets at the end of follow-up increased to a level comparable to healthy controls. Although no functional defects of DCs was found in chronic hepatitis C patients in comparison with healthy controls, in patients without SVR had a lower CD83 expression and higher interleukin-10 production of DCs than SVR patients. The results suggest that low CD83 expression and high IL-10 production of DCs at the baseline may predict a poor virologic response to 24-week PEG-IFN plus ribavirin therapy in HCV genotype 1 patients.