Thymic selection

Thymic selection is a process in the thymus gland where immune cells called T cells are tested for their ability to recognize the body's own proteins without attacking them. During this process, T cells that strongly react to the body’s own tissues are eliminated to prevent autoimmunity, while those that do not recognize them are also discarded because they can’t effectively defend against infections. The remaining T cells are those that can recognize harmful pathogens but tolerate the body's own tissues, helping the immune system distinguish between self and non-self safely.