Abstract: Objective To study the relationship between programmed death 1 (PD-1) and inflammatory response of autoimmune hepatitis (AIH) in liver tissues.Methods A total of 60 AIH patients in our hospital were selected as hepatitis group, and were divided into remission stage group (18 cases) and activity stage group (42 cases) according to the degree of disease activity. Sixty healthy subjects in the same period were selected as healthy control group. The expression of PD-1 was detected by avidin-biotin-peroxidase complex immunohistochemical staining method, and the relationship of its expression with inflammatory response of AIH was analyzed. The correlations between PD-1 and total bilirubin (TB), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were studied. Results The expression of PD-1 in hepatitis group was significantly higher than that in healthy control group (P<0.05), besides, the expression of PD-1 in active stage group was significantly higher than that in remission stage and healthy control group (P<0.05). The expression of PD-1 in grade of liver necroinflammation (G) 0 AIH patients was significantly lower than that in G1-G2 and G3-G4 patients (P<0.05). The expression of PD-1 in G1-G2 AIH patients was significantly lower than that in G3-G4 patients (P<0.05). The expression of PD-1 was positively correlated with TB, AST and ALT (r = 0.853, 0.863, 0.884, P=0.000, 0.000, 0.000). Conclusion There is a certain correlation between PD-1 and the degree of AIH inflammation, suggesting that PD-1 may be involved in the development and progression of AIH, which clinical attention should be paid to.

Key words: Programmed death 1, Autoimmune hepatitis, Inflammation