A. Akbar

Human memory T cell pools proliferate and differentiate at varying rates that are determined by the frequency of lifelong antigenic re-encounter with different specific antigens. An important question is whether certain specific pools of memory T cells may be driven to exhaustion in elderly subjects, a pertinent point in view of the increasing human life expectancy. An emerging consensus is that cytomegalovirus (CMV), a b-herpesvirus with a prevalence of 60-90% worldwide, is an agent that induces specific T cells to extreme differentiation. The question that begs to be asked is whether this may explain why CMV seropositivity and the presence of highly differentiated CMV-specific T cells are part of a cluster of immune parameters that have been recently shown to predict the early mortality of elderly humans.