The thymus (pl.: thymuses or thymi) is a specialized primary lymphoid organ of the immune system . Within the thymus, T cells mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. The thymus gland is an important organ of the lymphatic system located in the chest behind the breastbone. It plays a crucial role in the development and maturation of immune cells known as T cells, which are essential for the body's immune response. Learn about the thymus gland , a soft organ in your chest that produces T cells and hormones for your immune system. Find out what can go wrong with your thymus and how to recognize the signs of thymus problems.
