Nestled beneath the sternum, the thymus gland—named by the Greeks who believed it housed the soul—shrinks with age and has long been considered obsolete after childhood. However, recent research suggests it may play a crucial role in immunity and longevity.

The thymus is where T lymphocytes (T cells) mature. These white blood cells originate from stem cells in the bone marrow and travel to the thymus to become functional immune cells that hunt infected or cancerous cells.

According to Professor Paola Bonfanti of University College London, the thymus begins shrinking in childhood, accelerates during puberty, and continues throughout adulthood. This reduces the production of new T cells, weakening the immune system over time.

A 2023 study found that people whose thymus was removed had a threefold higher risk of death and double the risk of cancer. In March, Harvard Medical School researchers published a study in Nature showing that adults with a healthy-appearing thymus lived longer and had lower rates of cardiovascular disease and cancer.

However, Bonfanti cautions that these findings are correlational: healthier individuals may simply preserve thymic tissue better. Whether regenerating the thymus can directly improve health or extend lifespan remains unproven.

Scientists note the thymus can regenerate naturally, as it atrophies during pregnancy and recovers after childbirth. Philadelphia-based biotech company Tolerance Bio is developing an antibody to slow thymus shrinkage, with clinical trials planned for next year.

Bonfanti believes that if thymus regeneration proves safe, it will first be used in patients with severe medical needs, where benefits outweigh risks, rather than in healthy individuals seeking to slow aging.

Source: www.aljazeera.com