Age-related susceptibility of naive and memory CD4 T cells to apoptosis induced by IL-2 deprivation or PHA addition.

The increased age-associated incidence of infectious and cancer diseases has been related to the alteration of immune functioning found in the elderly (immunosenescence). The reduction of naive T cells, which determine an impaired ability to mount immune responses to new antigens, represents a hallmark of the aging process. The aim of this study was to evaluate the susceptibility to apoptosis of purified naive and memory CD4(+) T cells from peripheral blood of healthy people ranging in age from 20 to 98 years.