Heterogeneity of immune responsiveness in healthy elderly subjects.
We studied a group of healthy elderly subjects (satisfying the SENIEUR Protocol admission criteria), chosen as a model of age-associated immune deficiency on the basis of their reduced skin reactivity to recall antigens. Results show that aged subjects, taken as a whole, display impaired T-cell functions: reduced blastogenetic responses to mitogens, IL-2 production, responsiveness to exogenous IL-2, and percentage of Tac positive blasts. However, the age-associated immune defect shows a wide range of impairment, even in a relatively homogeneous group of anergic/hypoergic subjects. In fact, a considerable proportion of our elderly subjects displays responses comparable with those of adult controls. These observations suggest that (a) immune deficiency is not a characteristic of aging per se; (b) cutaneous delayed hypersensitivity is not a criterion sensitive enough to identify people with age-associated immune deficit; and (c) more than one test is required to evaluate T-cell impairment in aging.
D000375:Aging; D000917:Antibody Formation; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007108:Immune Tolerance; D007109:Immunity; D007111:Immunity, Cellular; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000096:biosynthesis / Q000494:pharmacology; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000145:classification; D008297:Male; D011971:Receptors, Immunologic / Q000378:metabolism; D015375:Receptors, Interleukin-2
D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2