Memory T cell homeostasis and senescence during aging.
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 concerning immunity is whether certain specific pools of memory T cells are driven to exhaustion in elderly subjects, a pertinent point in view of increasing human life expectancy. An emerging consensus is that cytomegalovirus (CMV), a beta-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 answered is whether this can explain why CMV seropositivity and the presence of highly differentiated CMV-specific T cells are included in a cluster of immune parameters that have been shown recently to predict the early mortality of elderly humans.
Akbar
Arne N
AN
Department of Immunology and Molecular Pathology, Division of Infection and Immunity, University College London, UK. aakbar@ucl.ac.uk
Fletcher
Jean M
JM
D000375:Aging; D000818:Animals; D002454:Cell Differentiation; D003587:Cytomegalovirus / Q000276:immunology; D003586:Cytomegalovirus Infections / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D012307:Risk Factors; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000821:virology