Abstract: Objective The aim of this study was to investigate the balance of peripheral blood regulatory T lymphocytes (Treg)/helper T cell 17 (Th17) in patients with chronic hepatitis B (CHB) and its impact on response to telbivudine treatment.Methods 123 patients with CHB, 112 hepatitis B viral carriers and 95 healthy persons were recruited in this study in our hospital between February 2019 and March 2020, and all CHB patients received telbivudine treatment for 48 weeks. Peripheral blood Treg and Th17 cell percentages were detected by FCM. The multivariate Logistic regression was applied to analyze the impacting factors of non-response to nucleotide analogue treatment in patients with CHB. The area under the receiver operating characteristic curve (AUROC) was applied to analyze the efficacy of Treg/Th17 ratio in predicting the response to antiviral treatment.Results The percentages of Treg cells and Th17 cells as well as Treg/Th17 ratio in patients with CHB were (4.8±1.1)%, (6.1±1.7)% and (0.8 ± 0.1)], significantly higher than [(1.1±0.3)%, (2.5±0.8)% and (0.4±0.0), P<0.05] in HBV carriers, or [(0.9±0.2)%, (2.1±0.6)% and (0.4±0.0), P<0.05] in healthy persons; at the end of week 12, week 24 and week 48, the normalization rates of serum ALT levels were 65.9%, 77.2% and 93.5%, serum HBV DNA loss were 61.8%, 72.3% and 82.9%; at the end of week 48, 21 patients (17.1%) failed to response to antiviral treatment; the percentages of re-treated patients, poor medication compliance, low baseline serum ALT and HBV DNA loads, Treg cells and Treg/Th17 ratios in non-responders were significantly different as compared to those in response group (all P<0.05); the Logistic regression analysis showed that re-treatment, baseline HBV DNA load and ALT levels, and Treg/Th17 ratio were the independent factors for non-response to nucleotide analog treatment in patients with CHC (OR=3.695, OR=3.232, OR=3.866, OR=4.039, all P<0.05); the ROC analysis showed that the optimal cut-off value of blood Treg/Th17 ratio for predicting non-response to nucleotide analogues treatment in patients with CHB was 0.83, with the AUC of 0.923 (95% CI: 0.860-0.963), ant its sensitivity of 81.0%, the specificity of 87.3%, and the accuracy of 91.1%.Conclusion The percentages of peripheral blood Treg cells increase in patients with CHB, which might impact on the response to antiviral therapy and need further investigation.

Key words: Hepatitis B, Telbivudine, Regulatory T lymphocytes, Helper T cells 17, Therapy