what does thymosin do
1 The thymus gland, located behind your sternum and between your lungs, is only active until puberty. 2  After puberty, the thymus starts to slowly shrink and become replaced by fat. 3  Thymosin is the hormone of the thymus, and it stimulates the development of disease-fighting T cells.he thymus reaches its maximum weight (about 1 ounce) during puberty. Thymosin: The Hormone of the Thymus. Thymosin stimulates the development of T cells. Throughout your childhood years, white blood cells called lymphocytes pass through the thymus, where they are transformed into T cells.