The thymus's role in keeping the body healthy and in illness

Thymic involution leads to decreased T-cell development and increased susceptibility to infectious diseases and autoimmune disorders.

• The thymus, essential for T-cell development, decreases in size and cellularity with age, a process known as thymic involution.
• Thymic involution results in fewer naive T cells being produced and a higher proportion of memory T cells in circulation.
• Alterations in the T-cell receptor repertoire occur due to thymic involution, impacting immune responses.
• Increased susceptibility to infections, such as COVID, along with a higher risk for autoimmune disorders and cancers, is associated with changes in the T-cell pool from thymic involution.
• The mechanisms behind thymic involution involve structural loss and genetic mutations that contribute to immunosenescence.

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