Which structure is primarily responsible for hormone production crucial for the immune system?

The thymus is primarily responsible for the production of hormones that are crucial for the development and function of the immune system. It specifically produces thymosin and other thymic hormones that play a key role in the maturation of T-lymphocytes (T-cells), which are essential for adaptive immunity. The thymus is especially active during childhood and gradually atrophies with age, but its hormones are vital for establishing a functional immune response.

In comparison, the thyroid gland primarily regulates metabolism and energy levels through the production of thyroid hormones. The pancreas produces insulin and glucagon, which are critical for glucose control and metabolism rather than directly influencing immune function. The adrenal cortex produces corticosteroids, which can modulate immune responses but are not primarily responsible for the development and function of immune cells, making the thymus the most directly involved in immune system hormone production.