GENERAL HISTOLOGY

Detailed explanation-1: -The thymus is special in that, unlike most organs, it is at its largest in children. Once you reach puberty, the thymus starts to slowly shrink and become replaced by fat. By age 75, the thymus is little more than fatty tissue. Fortunately, the thymus produces all of your T cells by the time you reach puberty.

Detailed explanation-2: -Summary: A critical immune organ called the thymus shrinks rapidly with age, putting older individuals at greater risk for life-threatening infections. A new study reveals that thymus atrophy may stem from a decline in its ability to protect against DNA damage from free radicals.

Detailed explanation-3: -Age-related regression of the thymus is associated with a decline in naïve T cell output. This is thought to contribute to the reduction in T cell diversity seen in older individuals and linked with increased susceptibility to infection, autoimmune disease, and cancer.

Detailed explanation-4: -Thymic involution is the genetically programmed aging process via which the thymus undergoes a progressive reduction in size due to the loss of thymic epithelial cells and decrease in thymopoiesis (Bar-Dayan, Afek, Bar-Dayan, Goldberg, & Kopolovic, 1999; Taub & Longo, 2005).