Abstract: Objective This study was conducted to explore the clinical implications of serum leptin level, and peripheral blood regulatory T cells (Tregs) and helper T 17 (Th17) cells in patients with autoimmune hepatitis (AIH). Methods 69 patients with AIH were enrolled in our hospital between March 2018 and March 2023, and all underwent liver biopsies and received standardized prednisone and azathioprine combination therapy. Serum cytokine levels were assayed by ELISA, and the percentages of peripheral blood Tregs and Th17 cells were detected by FCM. Results Serum leptin, IL-17, IL-22 and TNF-α, and percentage of blood Th17/CD4⁺ cells and the Th17/Tregs cell ratio in 22 patients with severe AIH were (335.6±84.2)ng/mL, (18.5±4.1)pg/mL, (48.7±11.4)pg/mL, (5.6±0.9)ng/mL, (3.3±1.2)% and (20.1±3.0), all significantly higher than [(66.9±13.8)ng/mL,(6.9±2.5)pg/mL, (13.8±3.3)pg/mL, (1.1±0.4)ng/mL, (2.5±0.3)% and (12.4±1.5), respectively, P<0.05], while blood platelet count, serum IL-10 level and percentage of blood Tregs/CD4⁺ cells were (129.8±29.4)×10⁹/L, (2.3±0.7)pg/mL and (1.6±0.4)%, all much lower than [(174.2±35.6)×10⁹/L, (4.8±0.9)pg/mL and (2.0±0.8)%, P<0.05]in 47 patients with mild/moderate AIH; the histo-pathological examination showed G1-2 histological activity in 42 cases and G3-4 in 27 cases; serum leptin, IL-17, IL-22 and TNF-α levels, percentage of blood Th17/CD4⁺ cell and the Th17/Tregs cell ratio in patients with G3-4 were significantly higher than, while the platelet count, percentage of Tregs/CD4⁺ cells and serum IL-10 level were much lower than in those with G1-2(P<0.05); all patients in our series obtained complete response (CR) after immunosuppression therapy, and the CR occurred less than three months in 35 cases, three to six months in 23 cases and longer than six months in 11 cases; the patients with increased serum leptin levels, percentages of blood Tregs/CD4⁺ and Th17/CD4⁺ cells, and the Th17/Tregs cell ration cost longer period for CR (P＜0.05). Conclusion The surveillance of serum leptin levels and peripheral blood Tregs and Th17 cells might predict the efficacy of immunosuppression therapy, which needs further clinical verification.

Key words: Autoimmune hepatitis, Prednisone, Leptin, Regulatory T cells, Helper T cells, Therapy