Prevention of a lethal CMV organ infection by ACT of virus-specific CD8+ T cells was originally demonstrated in the preclinical model of mice infected with mCMV after sublethal γ-irradiation (22–24), years before ACT with cell culture-propagated CD8+ cytolytic T-cell lines (CTLL) specific for the hCMV tegument protein pUL83/pp65 was shown to control human infection (18, 19). Here, CD8A is linked to infection.