title: Blood T-lymphocyte functions in healthy adults in relation to age.
abstract: Blood T-lymphocyte functions were studied in 167 healthy adults (age range 19-91 years). Lymphocyte DNA synthesis induced by concanavalin A, pokeweed mitogen and PPD antigen declined with age while the spontaneous DNA synthesis remained essentially unchanged. Relative and total T-cell counts but not total lymphocyte counts were moderately decreased in elderly persons. The lymphocyte response to mitogens correlated with the PPD-induced activation in vitro. Lymphocyte and T-cell counts did not show any association with the response to mitogens and antigen. A few subjects were tested on several occasions during 2-7 years confirming a good reproducibility of the techniques employed. Thus ageing is associated with diminished number of T-cells and impairment of lymphocyte activation by T-cell mitogens and PPD antigen. The clinical importance of this general age-related T-cell deficiency remains largely unresolved.
mesh_terms: D000328:Adult; D000375:Aging; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D005260:Female; D006801:Humans; D037102:Lectins / Q000494:pharmacology; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000187:drug effects / Q000502:physiology*
chemical_list: D037102:Lectins; D004247:DNA