[Clinical profiles of circulating plasmacytoid dendritic cells in chronic hepatitis B patients in response to pegylated-interferon alfa-2a treatment].

OBJECTIVE: To investigate the changes in circulating plasmacytoid dendritic cells (pDCs) in patients with chronic hepatitis B (CHB) during the course of treatment with pegylated-interferon alfa-2s (peg-IFNa-2a) and to determine the correlations with therapeutic response. METHODS: Forty-one patients with CHB who were receiving peg-IFNa-2a antiviral treatment for 48 weeks were enrolled in the study.Expression of the Toll-like receptor 9 (TLR9) on and frequency and functionality of the pDCs were analyzed at treatment weeks 0, 2, 12, 24, 36 and 48. RESULTS: All patients exhibited an initially rapid decrease in the numbers of circulating pDCs and showed CpG-induced endogenous IFNa production within the first 2 weeks of treatment.Subsequently, all responders displayed a continuous increase in pDC numbers as well as functionality, both of which peaked around week 12 of treatment; in addition, these treatment responses were accompanied by significantly increased levels of type 1 T helper cytokines (P less than 0.05), which did not occur in the non-responders. CONCLUSION: pDCs are involved in the initial therapeutic immune response stimulated by peg-IFNa-2a treatment.Recovery of blood pDC number and functionality may represent a predictor of favorable response to peg-IFNa-2a antiviral treatment in patients with CHB.