Identification of the key autoantigen in AIH-2 has led to the establishment of models with liver expression of human CYP2D6, delivered by an adenovirus (Ad-2D6) [105], leading to persistent AIH-like disease with interface hepatitis, and liver infiltration of CD4 and CD8 T cells, B cells, as well as neutrophils, macrophages and dendritic cells, and positive anti-LKM1 antibody [120–122]. This evidence concerns the gene CD4 and autoimmune hepatitis.