TOX and viral infectious disease: Besides the detection of TOX in the LCMV mouse model, upregulation of TOX has also been demonstrated in human viral infectious diseases such as chronic hepatitis B (HBV) (34), human immunodeficiency virus (35), HCV (11, 28), Epstein-Barr virus (34, 35), cytomegalovirus (34, 35), and influenza (FLU) (11, 28).