title: T cell activation through different membrane structures (T3/Ti, T11, T44) and frequency analysis of proliferating and interleukin-2 producer T lymphocyte precursors in aged individuals.
abstract: It is well known that the proliferative responsiveness of T cells of aged subjects is depressed in both autologous mixed lymphocyte reaction (AMLR) and in PHA-induced cultures. In the present study we analyzed T cell activation through different stimulatory pathways (such as T3/Ti antigen receptor, T11 complex and T44 molecule). Moreover, we studied Interleukin-2 (IL-2) release performing a limiting dilution analysis of the proliferative capability of peripheral blood T cells, employing a high efficiency cloning technique. Our results demonstrate normal proliferation of T3-induced T cells in aged subjects, whereas T11- and T44-induced T cell proliferations are depressed in aged subjects. In addition, studies at clonal level reveal a normal percentage of IL-2 producer T cell in aged individuals. In conclusion, our data suggest that the T cell in aged subjects are normal in number, but they have a decreased capacity of lymphokine production.
authors.affiliation: Department of Internal Medicine, University of Genoa, Italy.
authors.forename: G W
authors.initials: GW
authors.lastname: Canonica
authors.forename: M
authors.initials: M
authors.lastname: Caria
authors.forename: D
authors.initials: D
authors.lastname: Venuti
authors.forename: G
authors.initials: G
authors.lastname: Cipro
authors.forename: G
authors.initials: G
authors.lastname: Ciprandi
authors.forename: M
authors.initials: M
authors.lastname: Bagnasco
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008297:Male; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*
chemical_list: D007376:Interleukin-2; D010835:Phytohemagglutinins