TRIIM Regenerated Thymus, Reversed Clocks

Researchers tested whether rebuilding the thymus, an immune organ that shrinks and fills with fat with age, could shift immune ageing in healthy older men. Nine men aged 51-65 received a year of a three-drug regimen. In seven, chest MRI showed a rise in the thymus's fat-free fraction; the smaller change in breastbone marrow supports a tissue effect localized to the thymus. Naïve T cells, newly made cells that have not met an infection, also increased. All four DNA-methylation clocks, tests that estimate biological age from chemical marks on DNA, moved younger by a mean 6.48 years per year. One clock retained a 2.1-year gain six months later. This small pilot links tissue restoration with immune and epigenetic measurements, but cannot show that one caused the others.