Abstract: Objective To investigate the changes of peripheral blood lymphocyte programmed death-1 (PD-1) and PD-ligand 1 (PD-L1) expression in patients with autoimmune hepatitis (AIH) receiving tripterygium wilfordii polyglycosides and magnesium iso-glycyrrhizate. Methods 76 patients with AIH were randomly divided into control (n=38) and observation group (n=38). The patients in the control group were treated with magnesium isoglycyrrhizate, and those in the observation group were treated with tripterygium wilfordii polyglycosides and magnesium combination. The regimen lasted for 24 weeks in both groups. The expression of PD-1 and PD-L1 percentages on peripheral blood T lymphocytes were detected by CyFlow Counter flow cytometry, including PD-L1⁺/CD4⁺, PD-L1⁺/CD8⁺, PD-1⁺/CD4⁺ and PD-1⁺/CD8⁺, and serum γ-interferon (IFN-γ) was assayed by ELISA. Results At the end of 24 week treatment, serum alanine aminotransferase (ALT) level in the observation group was (48.9±9.7) U/L, significantly lower than that in the control group (77.5±11.2) U/L, P<0.05), serum aspertate aminotransferase (AST) level was (45.5±7.3) U/L, significantly lower than that in the control group ((81.3±9.5) U/L, P<0.05), and serum alkaline phosphatase (ALP) levels was (65.5±2.3) U/L, significantly lower than that inthe control group (91.3±5.8) U/L, P<0.05); the percentage of peripheral blood lymphocyte PD-L1⁺/CD4⁺ was (15.4±4.5) %, significantly lower than that in the control group , the PD-L1⁺/CD8⁺ percentage was (6.5±2.7) %, significantly lower than that in the control group , the PD-1⁺/CD4⁺ was (7.4±2.6) %, significantly lower than that in the control group , and the peripheral blood lymphocyte PD-1⁺/CD8⁺ percentage was (7.5 ± 1.7)%, significantly lower than that in the control group ; serum globulin level was (13.4±1.5) g/L, significantly lower than that in the control group [(18.3±1.8) g/L, P<0.05), serum IgG level was (10.9±2.4) mg/mL, significantly lower than that in the control group [(13.6±2.9) mg/mL, P<0.05), and serum IFN-γ level was (13.0±2.4) ng/mL, significantly lower than [(18.1±2.8) ng/mL, P<0.05) in the control group.Conclusion The combination of tripterygium wilfordii polyglycosides and magnesium iso-glycyrrhizate in treatment of patients with AIH have a short-term efficacy, which might be related to the reduction of PD-1 and PD-L1 expression on peripheral blood T lymphocytes, and restoration of immune dysfunction.

Key words: Autoimmune hepatitis, Tripterygium wilfordii polyglycoside, Magnesium iso-glycyrrhizate, Programmed death -1, Programmed death -1 ligand, Therapy