Serum levels of interleukin-22 and hepatitis B core-related antigen are associated with treatment response to entecavir therapy in chronic hepatitis B

Aim: We sought to clarify the associations between serum cytokines and chemokines, hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg), and hepatitis B virus (HBV) DNA and response to entecavir therapy in chronic hepatitis B. Methods: We analyzed six cytokines (interleukin [IL]-2, IL-6, IL-10, IL-12p70, IL-21 and IL-22) and five chemokines (CCL2, CCL3, CXCL9, CXCL10 and CXCL11) before and at 6, 12 and 24 months during entecavir therapy in 48 chronic hepatitis B patients. Quantitative measurement of HBsAg, HBcrAg and HBV DNA was performed. A virological response (VR) was defined as serum HBV DNA of less than 2.1 log copies/mL by treatment month 24. Results: Thirty-nine patients (81%) achieved a VR. Serum IL-6 (P = 0.031), CXCL-9 (P = 0.002), and CXCL-10 (P = 0.001) were high in chronic HBV and correlated positively with transaminases and bilirubin. Before treatment, elevated IL-22 (P = 0.031) and lower HBsAg (P = 0.001) and HBcrAg (P < 0.001), but not HBV DNA, were associated with a favorable treatment outcome. In multivariate analysis, high IL-22 (hazard ratio = 13.67, P = 0.046) and low HBcrAg (hazard ratio = 10.88, P = 0.048) were independently associated with a VR. The levels of IL-22 (P < 0.001), HBsAg (P < 0.001), and HBcrAg (P < 0.001) all decreased from baseline to 24 months of treatment in virological responders. Conclusion: Serum IL-22 and HBcrAg are predictive markers of a VR to entecavir therapy in patients with chronic hepatitis B.