Background:Cytokines play an important role in occurrence and recovery of hepatitis B virus (HBV) infection.The aim of this study was to investigate the changes of cytokines concentration and its correlation to alanine aminotransferase (ALT),HBV deoxyribonucleic acid (HBV-DNA),hepatitis B envelope antigen (HBeAg),and HBV surface antigen (HBsAg) in the development of chronic hepatitis B (CHB).Methods:Thirteen healthy individuals (HI),30 chronic HBV-infected patients in immune tolerant (IT) phase,and 55 CHB patients were enrolled between August 2015 and May 2017.The peripheral blood samples were collected from all individuals.The levels of interferon (IFN)-α2,interleukin (IL)-1 0,transforming growth factor (TGF)-β1,HBV-DNA,HBsAg,and HBeAg and liver function were measured.The quantitative determinations of cytokines levels,including IFN-α2,IL-10,and TGF-β1 were performed using Luminex multiplex technology.The correlation of cytokines to ALT,HBV-DNA,HBsAg,and HBeAg was analyzed by linear regression analysis.Results:IFN-α2 levels were similar between HI and IT groups (15.35 [5.70,67.65] pg/ml vs.15.24 [4.07,30.73] pg/ml,Z =-0.610,P =0.542),while it elevated significantly in CHB group (35.29 [15.94,70.15] pg/ml vs.15.24 [4.07,30.73] pg/ml;Z =-2.522,P =0.012).Compared with HI group (3.73 [2.98,11.92] pg/ml),IL-10 concentrations in IT group (5.02 [2.98,10.11] pg/ml),and CHB group (7.48 [3.10,18.00] pg/ml) slightly increased (x2 =2.015,P =0.365),and there was no significant difference between IT and CHB group (Z=-1.419,P =0.156).The TGF-β1 levels among HI (3.59 ± 0.20 pg/ml),IT (3.62 ± 0.55 pg/ml),and CHB groups (3.64 ± 0.30 pg/ml) were similar (x2 =2.739,P =0.254).In all chronic HBV-infected patients (including patients in IT and CHB groups),the elevation of IFN-α2 level was significantly associated with ALT level (β =0.389,t =2.423,P =0.018),and was also negatively correlated to HBV-DNA load (β =-0.358,t =-2.308,P =0.024),HBsAg (β =-0.359,t =-2.288,P =0.025),and HBeAg contents (β =-0.355,t =-2.258,P =0.027).However,when both ALT level and cytokines were included as independent variable,HBV-DNA load,HBsAg,and HBeAg contents were only correlated to ALT level (β =-0.459,t =-4.225,P =0.000;β =-0.616,t =-6.334,P =0.000;and β =-0.290,t =-2.433,P =0.018;respectively).Conclusions:IFN-α2 elevation was associated with ALT level in patients with chronic HBV infection.However,in CHB patients,only ALT level was correlated to HBV-DNA,HBsAg and HBeAg contents.