PDCD1 and autoimmune hepatitis: A significant number of PD‐1+CD8+ T cells with an effector memory phenotype and function are present in the peripheral blood of healthy adults, which is markedly different from the traditional concept of HIV‐induced exhausted T cells.[4] There is limited research on PD‐1+CD8+ T cells in autoimmune liver diseases, but recent studies have found a significant expansion of PD‐1+CD8+ T cells in the livers of patients with autoimmune hepatitis (AIH).