Meet Brunkow, Ramsdell and Sakaguchi — the Nobel Prize-winning trio who taught the world how the immune system knows when to stop

Shimon Sakaguchi, Mary E. Brunkow, and Fred Ramsdell received the 2025 Nobel Prize in Medicine for decoding peripheral immune tolerance. Sakaguchi discovered regulatory T cells, while Brunkow and Ramsdell identified the Foxp3 gene controlling them. Their groundbreaking work transformed immunology, offering new avenues for treating autoimmune disorders, cancer, and transplant rejection.