The thymus is a lymphoid gland localized between the lungs in the anterior superior mediastinum (in the chest). Its cortex (i.e., external layer) is constituted by lymphatic tissue, with the internal portion containing lymphocytes. The thymus has also a thick reticular structure comprised of groups of granular cells enveloped by epithelial cells, known as Hassall's corpuscles. Much remains to be found about the thymus' physiological role and products. Thymine (2,4-Dihydroxy-5-methylpyrimidine), for instance, was first isolated from this organ and seems to be an important nutritional compound against macrocytic anemia. However, the better understood thymic function is related to its role in the preprocessing of stem cells into different lymphocytes, promoting their maturation and specialization (i.e., differentiation) as millions of functional T lymphocytes (where "T" stands for "thymus"). T lymphocytes are a family of white blood cells pertaining to the acquired immunity system that...