title: Age-related changes in CD8 T cell homeostasis and immunity to infection.
abstract: Studies of CD8 T cell responses to vaccination or infection with various pathogens in both animal models and human subjects have revealed a markedly consistent array of age-related defects. In general, recent work shows that aged CD8 T cell responses are decreased in magnitude, and show poor differentiation into effector cells, with a reduced arsenal of effector functions. Here we review potential mechanisms underlying these defects. We specifically address phenotypic and numeric changes to the naïve CD8 T cell precursor pool, the impact of persistent viral infection(s) and inflammation, and contributions of the aging environment in which these cells are activated.
authors.affiliation: Department of Immunobiology and the Arizona Center on Aging, University of Arizona College of Medicine, Tucson, AZ 85724, United States. nikolich@email.arizona.edu
authors.forename: Janko
authors.initials: J
authors.lastname: Nikolich-Žugich
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Uhrlaub
authors.forename: Kristin R
authors.initials: KR
authors.lastname: Renkema
authors.forename: Megan J
authors.initials: MJ
authors.lastname: Smithey
mesh_terms: D000375:Aging; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D006706:Homeostasis; D006801:Humans; D007113:Immunity, Innate; D007239:Infections / Q000276:immunology*; D010641:Phenotype