In patients with AIH in biochemical remission, serum IL-21 levels were still elevated, despite a reduction in serum IL-18, CCL20, CCR6, CXCL9, and CXCR3 levels (Additional file 2: Figure 1), and significantly and positively correlated with serum IgG levels. Here, CXCL9 is linked to autoimmune hepatitis.