Signs of EBV-specific T-cell exhaustion included elevated PD-1 and decreased cytotoxic T-cell functions in EBV CD8+ T cells in SLE, diminished T- and B-cell memory response in CFS, and reduced EBV CD8+ T-cell functionality and exhaustion in MS [115,116,117]. The gene discussed is CD8A; the disease is myalgic encephalomeyelitis/chronic fatigue syndrome.