CD4 and autoimmune hepatitis: For example, substantial infiltration of CD4+ T cells and the release of excessive levels of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), along with consequent hepatocyte necrosis, have been extensively reported in the liver tissues of patients with autoimmune hepatitis (AIH) 2.