Quantitation of Plasmacytoid Dendritic Cells in Chronic Hepatitis B Patients with HBeAg Positivity during PEG-IFN and Entecavir Therapy

Plasmacytoid dendritic cells (pDCs) are crucial for control of chronic hepatitis B (CHB) virus infection. In this study, we evaluated the frequencies of pDCs and expression of functional molecules on pDCs in patients treated with PEG-IFN-α-2a or entecavir (ETV) and investigated changes during treatment. The mean fluorescence intensity of CD86 (CD86MFI) on the surface of pDCs and frequencies of pDCs and CD86⁺ pDCs in peripheral blood were measured. Compared with baseline, CD86⁺ pDC% and CD86MFI increased obviously after PEG-IFN-α-2a treatment for 12 and 24 weeks. For patients treated with ETV, only pDC% increased observably after treatment weeks 12 and 24 (P < 0.001) compared with baseline. Hepatitis B surface antigen (HBsAg) decline was significantly associated with elevated CD86⁺ pDC% (r = 0.348, P = 0.015) during PEG-IFN-α-2a treatment. In the HBsAg response group, CD86⁺ pDC% and CD86MFI (P < 0.001) increased observably after PEG-IFN-α-2a therapy, whereas only CD86MFI had a statistically significant difference after therapy compared with baseline (12 weeks versus 0 weeks, P = 0.022; 24 weeks versus 0 weeks, P = 0.015) in the HBsAg nonresponse group. CD86⁺ pDC% between the 2 groups had statistically significant differences at baseline (P = 0.001) and at the treatment time points of 12 and 24 weeks (P < 0.001), respectively. For patients receiving ETV therapy, pDC% increased observably, but CD86⁺ pDC% decreased significantly (P < 0.001) in the HBV DNA nonresponse group during early treatment with ETV. In CHB patients, HBsAg response in PEG-IFN-α-2a therapy correlated with the increase of CD86⁺ pDC% and HBV DNA nonresponse in ETV treatment correlated with the decrease of CD86⁺ pDC%.