The calcium response of human T lymphocytes is decreased in aging but increased in Alzheimer's dementia

Background: A significant increase in the [Ca2+](i) response of single T ly mphocytes to mitogenic stimulation with phytohemagglutinin is reported for 27 Alzheimer patients compared with 27 healthy gender- and age-marched cont rol subjects, regardless of gender. Methods: The [Ca2+](i) signals of T lymphocytes were assessed using the Fur a-2-AM method. Results: In Alzheimer's disease (AD) the reaction pattern is similar to tha t seen in a group of 27 young healthy control subjects who exhibited a mark ed [Ca2+](i) rise after stimulation. During normal aging the reaction patte rn of T cells is significantly attenuated in comparison to that found in yo ung subjects. In healthy control subjects differences in age-related change s in calcium homeostasis are highly significant among women, young women sh owing the most intense cell response. Conclusions: The elevation of [Ca2+](i) appears to be a prerequisite for ap optosis, which is suggested to be involved in the neuronal death occurring in AD. An increased [Ca2+](i) in AD is consistent with processes leading to neurodegeneration in AD. (C) 1999 Society of Biological Psychiatry.