Résumé
Objective:To study the characteristics and clinical significance of mitochondrial injury of T lymphocyte subsets in patients with autoimmune hepatitis (AIH).Methods:The clinical data of 57 patients with AIH (AIH group) from June to December 2021 in Hangzhou Xixi Hospital were retrospectively analyzed, while 60 healthy physical examiners were included as healthy group. The peripheral blood T lymphocyte subsets (CD 8+ T lymphocyte count and CD 4+ T lymphocyte count) were detected by flow cytometry, and matched mitochondrial staining value according to certain algorithm was used to determine the mitochondrial damage of helper T lymphocyte (Th cell) and suppressor T lymphocyte (Ts cell). The levels of IgG, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured using a Roche E170 automatic electrochemiluminescence immunoassay. Anti-nuclear antibody (ANA) titer was measured by immunofluorescence. Multivariate Logistic regression was used to analyze the independent risk factors of mitochondrial damage of Th cell and Ts cell in patients with AIH. Results:The ALT, AST, IgG, positive rate of ANA titer, CD 4+ T lymphocyte count, CD 8+ T lymphocyte count, rate of Th cell mitochondrial injury and rate of Ts cell mitochondrial injury in AIH group were significantly higher than those in healthy group: (118.90 ± 37.61) U/L vs. (30.96 ± 14.37) U/L, (102.40 ± 36.51) U/L vs. (31.12 ± 14.06) U/L, (18.40 ± 3.71) g/L vs. (13.89 ± 1.98) g/L, 96.49% (55/57) vs. 16.67% (10/60), 438 (323, 637) × 10 6/L vs. 398 (272, 469) × 10 6/L, 296 (211, 296) × 10 6/L vs. 270 (193, 322) × 10 6/L, 61.40% (35/57) vs. 8.33% (5/60) and 82.46% (47/57) vs. 11.67% (7/60), and there were statistical differences ( P<0.01 or <0.05). Multivariate Logistic regression analysis result showed that the AST elevated and CD 8+ T lymphocyte count reduced were the independent risk factors of Ts cell mitochondrial injury in patients with AIH ( OR = 1.06 and 0.99, 95% CI 1.01 to 1.10 and 0.99 to 1.00, P<0.05); the ALT elevated and IgG elevated were the independent risk factors of Th cell mitochondrial injury in patients with AIH ( OR = 1.08 and 1.66, 95% CI 1.02 to 1.14 and 1.11 to 2.48, P<0.05). Conclusions:It is of positive clinical significance to measure the T lymphocyte subtype mitochondrial injury in patients with AIH. The probability of mitochondrial injury of T lymphocyte subtype can be predicted by biochemical indexes such as ALT, AST and IgG, so as to indirectly evaluate the liver cell necrosis.