Among cytotoxic T cell responses, cells directed against the non-structural immediate early antigen (pUL122/123), and the structural tegument protein pp65 (pUL83) predominate and can account for up to 20 and 27 % of the total CD8+ T cells in a normal host in the absence of apparent infection or reactivation (Khan et al., 2007). Here, CD8A is linked to infection.