Objective      To elucidate the possible association between serum chemokine levels and virological response to PEGylated interferon (PegIFN) α-2a treatment in patients with chronic hepatitis B.        Methods      Thirty-six patients infected with genotype B hepatitis B virus (HBV) were recruited in this study. The serum levels of CXCL9

CXCL10

CCL3 and CCL5 were measured by ELISA before treatment. All the patients were treated with PegIFNα-2a 180 μg every week and then followed up for 6 months.        Results      The results of binary logistic regression analysis found that the serum levels of CXCL9 and aspartate aminotransferase (AST) before treatment were the independent predictors for early virological response. The patients were then divided into two groups including a high CXCL9 group (serum level of CXCL9≥39.51 ng/L) and a low CXCL9 group (serum level of CXCL939.51 ng/L). After the treatment for 3 months

the rates of early virological response were 78.95% (15/19) in the high CXCL9 group and 23.53% (4/17) in the low CXCL9 group

respectively (P0.05). After the treatment for 6 months

the rates of maintained virological response were 63.16% (12/19) in the high CXCL9 group and 11.76% (2/17) in the low CXCL9 group

respectively (P0.05).       Conclusion      Patients with a high level of CXCL9 have a high rate of virological response to PegIFNα-2a treatment

which may help to improve the efficacy of PegIFNα-2a treatment for patients with chronic hepatitis B.