Significance of T-Cell Subsets for Clinical Response to Peginterferon Alfa-2a Therapy in HBeAg-Positive Chronic Hepatitis B Patients

INTRODUCTION: The adaptive immune response may reflect the immunomodulatory efficacy during peginterferon alfa-2a (PEG-IFN α-2a) treatment in chronic hepatitis B (CHB) patients. We evaluated the predictive efficiency of T-cell subsets on patient’s response to PEG-IFN α-2a treatment. METHODS: The proportions of CD8(+)PD-1(+), CD8(+)Tim-3(+) and CD4(+)CD25(high) T-cells were measured at baseline and week 52 in CHB patients who underwent PEG-IFN α-2a treatment. The proportions of T-cell subsets were compared among different responders and non-responders (determined by biochemical, serological, and virological responses). RESULTS: The baseline proportions of the three T-cell subsets were significantly higher in CHB patients (65 cases) than in healthy controls (28 cases), while the proportions declined significantly after 52 weeks of PEG-IFN treatment. Responders (ALT < 40 IU/L, 89.2% [58/65]; HBV DNA < 2.7 log10 IU/ml, 66.2% [43/65]; and HBeAg seroconversion [SR], 53.9% [35/65]) experienced more pronounced declines in the proportion of T-cell subsets compared to non-responders. In particular, the baseline proportions of CD4(+)CD25(high) T-cells displayed significant difference between SR and non-SR groups. The stepwise logistic regression analysis identified that CD4(+)CD25(high) T-cells combined with baseline HBV DNA and ALT can predict SR and CR (ALT < 40 IU/L, HBV DNA < 2.7 log10 IU/mL and HBeAg seroconversion) after 52 weeks of PEG-IFN treatment with high accuracy. CONCLUSION: PEG-IFN therapy induces significant declines in the proportion of some key T-cell subsets in HBeAg-positive patients. The model constructed with CD4(+)CD25(high) T-cells combined with ATL and HBV DNA may help to predict the efficacy of PEG-IFN α-2a therapy.