title: The narrowing of the CD8 T cell repertoire in old age.
abstract: Immune function declines progressively with age, resulting in increased susceptibility of the elderly to infection and impaired responses to vaccines. A diverse repertoire of T cells is essential for a vigorous immune response, and an important manifestation of immune aging is the progressive loss of repertoire diversity, predominantly among CD8 T cells in both mice and humans. Importantly, perturbations in the peripheral T cell repertoire, including reduction of the CD4:CD8 ratio and cytomegalovirus-driven T cell clonal expansions, make a major contribution to the 'immune risk phenotype' defined for humans, which predicts two-year mortality in very old individuals.
authors.affiliation: Trudeau Institute, 154 Algonquin Ave, Saranac Lake, NY 12983, USA. mblackman@trudeauinstitute.org
authors.forename: Marcia A
authors.initials: MA
authors.lastname: Blackman
authors.forename: David L
authors.initials: DL
authors.lastname: Woodland
mesh_terms: D019264:Adoptive Transfer; D000368:Aged; D000375:Aging / Q000276:immunology*; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology; D003586:Cytomegalovirus Infections / Q000276:immunology; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D007156:Immunologic Memory; D008231:Lymphopenia / Q000209:etiology*; D038041:Lymphopoiesis; D051379:Mice; D018448:Models, Immunological; D009975:Orthomyxoviridae / Q000276:immunology; D009976:Orthomyxoviridae Infections / Q000276:immunology; D012306:Risk; D037182:T-Cell Antigen Receptor Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013950:Thymus Gland / Q000254:growth & development / Q000276:immunology