scribes the atrophy of the thymus as age advances. It is this atrophy that is thought responsible for the decreasing numbers of T cells as life proceeds and or the change in ratio of nanve vs. antigen activated (memory) T cells. The body is thought to expend a large amount of energy to maintain the health of the thymus and this cost simply gets too great once the aging process advances. Nanve cells produced by the thymus are cells that have not encountered a foreign antigen and therefore have no memory assigned to them. The study did yield results that suggested however that the thymus is able to produce adequate numbers of T cells throughout life and that proper numbers can often be restored if relief is given from concomitant diseases that tend to be present in the latter stages of life, and tend to have their own negative effects on the thymus. Adequate numbers of these lymphocytes however are not the only thing needed for a proper immunological response, as shown by further studies done using populations of T cells. According to work done by Linton et al., (1996) even newly produced nanve cells are unable at times to mount a timely defense and ar
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