title: CD28(-) T cells: their role in the age-associated decline of immune function.
abstract: The accumulation of CD28(-) T cells, particularly within the CD8 subset, is one of the most prominent changes during T-cell homeostasis and function associated with aging in humans. CD28, a major co-stimulatory receptor, is responsible for the optimal antigen-mediated T-cell activation, proliferation and survival of T cells. CD28(-) T cells exhibit reduced antigen receptor diversity, defective antigen-induced proliferation and a shorter replicative lifespan while showing enhanced cytotoxicity and regulatory functions. Gene expression analyses reveal profound changes of CD28(-) T cells in comparison to their CD28(+) counterparts and corroborate their functional differences. Here we review recent advances in our understanding of CD28(-) T cells and their role in the age-associated decline of immune function.
authors.affiliation: Laboratory of Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA. Wengn@mail.nih.gov
authors.forename: Nan-Ping
authors.initials: NP
authors.lastname: Weng
authors.forename: Arne N
authors.initials: AN
authors.lastname: Akbar
authors.forename: Jorg
authors.initials: J
authors.lastname: Goronzy
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D018106:CD28 Antigens / Q000235:genetics / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007372:Interferons / Q000276:immunology / Q000378:metabolism; D018121:Receptors, Cytokine / Q000276:immunology / Q000378:metabolism; D055607:Receptors, Natural Killer Cell / Q000276:immunology / Q000378:metabolism
chemical_list: D018106:CD28 Antigens; D015815:Cell Adhesion Molecules; D016207:Cytokines; D018121:Receptors, Cytokine; D055607:Receptors, Natural Killer Cell; D007372:Interferons