Abstract: Objective The aim of this study was to explore the implications of peripheral blood NKp46⁺ILC3 cells and Th17 cells in patients with autoimmune hepatitis (AIH). Methods 43 patients with AIH were encountered in our hospital between February 2016 and February 2020. The percentages of peripheral blood NKp46⁺ILC3 and Th17 positive mononuclear cells were detected by flow cytometry, and the area under receiver operating characteristic (ROC) curve (AUC) was adopted to analyze the efficacy of NKp46⁺ILC3 cells and Th17 cells in judging the liver histological activity grading in patients with AIH. Results The percentages of NKp46⁺ILC3 cells and Th17 cells in 10 patients with severe AIH were(0.2±0.2)% and (1.3±0.4)%, significantly lower or higher than [(0.5±0.2)% and (0.8±0.3)%, respectively, P<0.05] in 33 patients with mild to moderate AIH; the percentages of NKp46⁺ILC3 cells and Th17 cells in 12 AIH patients with liver histological activity G3 to G 4 were(0.3±0.2)% and (1.3±0.4)%, significantly lower or higher than [(0.5±0.2)% and (0.8±0.3)%, respectively, P<0.05] in 31 AIH patients with G1 to G2; the AUC was 0.774(95% CI:0.592-0.957), with the sensitivity (Se) of 75.0% and specificity (Sp) of 87.1% when the peripheral blood NKp46⁺ILC3 cells ≤0.3% was set as the cut-off-value, and the AUC was 0.853(95% CI:0.734-0.973), with Se of 66.7% and Sp of 90.3% when the peripheral blood Th17 cells ＞1.1% was set as the cut-off-value in judging severe liver histological activity grading. Conclusion The peripheral blood NKp46⁺ILC3 cells decrease, and that of Th17 cells increase in patients with AIH, and application of them might help judge the liver histological activity changes.

Key words: Autoimmune hepatitis, NKp46⁺ILC3 cells, Th17 cells, Clinical implication