title: Naïve and memory CD8 T cell pool homeostasis in advanced aging: impact of age and of antigen-specific responses to cytomegalovirus.
abstract: Alterations in the circulating CD8+ T cell pool, with a loss of naïve and accumulation of effector/effector memory cells, are pronounced in older adults. However, homeostatic forces that dictate such changes remain incompletely understood. This observational cross-sectional study explored the basis for variability of CD8+ T cell number and composition of its main subsets: naïve, central memory and effector memory T cells, in 131 cytomegalovirus (CMV) seropositive subjects aged over 60 years. We found great heterogeneity of CD8+ T cell numbers, which was mainly due to variability of the CD8 + CD28- T cell subset regardless of age. Analysis, by multiple regression, of distinct factors revealed that age was a predictor for the loss in absolute number of naïve T cells, but was not associated with changes in central or effector memory CD8+ T cell subsets. By contrast, the size of CD8+ T cells specific to pp65 and IE-1 antigens of CMV, predicted CD28 - CD8+ T cell, antigen-experienced CD8+ T cell, and even total CD8+ T cell numbers, but not naïve CD8+ T cell loss. These results indicate a clear dichotomy between the homeostasis of naïve and antigen-experienced subsets of CD8+ T cells which are independently affected, in human later life, by age and antigen-specific responses to CMV, respectively.
authors: Department of Clinical and Experimental Medicine, University of Parma, via Gramsci 14, 43126, Parma, Italy, rosanna.vescovini@unipr.it.
authors: Rosanna
authors: R
authors: Vescovini
authors: Francesco Fausto
authors: FF
authors: Fagnoni
authors: Anna Rita
authors: AR
authors: Telera
authors: Laura
authors: L
authors: Bucci
authors: Mario
authors: M
authors: Pedrazzoni
authors: Francesca
authors: F
authors: Magalini
authors: Adriano
authors: A
authors: Stella
authors: Federico
authors: F
authors: Pasin
authors: Maria Cristina
authors: MC
authors: Medici
authors: Adriana
authors: A
authors: Calderaro
authors: Riccardo
authors: R
authors: Volpi
authors: Daniela
authors: D
authors: Monti
authors: Claudio
authors: C
authors: Franceschi
authors: Janko
authors: J
authors: Nikolich-Žugich
authors: Paolo
authors: P
authors: Sansoni
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003430:Cross-Sectional Studies; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D006706:Homeostasis / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D010641:Phenotype
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral