GPT and autoimmune hepatitis: So far, autoantibodies against nuclear antigens (ANA) or smooth muscle antibodies (ASMA), combination of liver kidney type 1 (LKM1) and other liver biochemical indexes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma globulin and immunoglobulin G (IgG) are widely used as biomarkers for AIH diagnosis.