Nobel Prize for Regulatory T Cell Discoveries

On October 6, 2025 the Nobel Prize in Physiology or Medicine was awarded to Fred Ramsdell, Mary E. Brunkow and Shimon Sakaguchi for discoveries about peripheral immune tolerance and regulatory T cells. Sakaguchi first identified a distinct regulatory T‑cell subtype in 1995, and Brunkow and Ramsdell later showed that mutations in the FOXP3 gene are essential for regulatory T‑cell development. The Nobel Committee said the work has been decisive for understanding why most people do not develop serious autoimmune diseases. Researchers are using the insights to pursue new treatments for autoimmune disorders, improve transplant success and enhance cancer immunotherapy. Ramsdell, an Elmhurst native and San Francisco‑area biotech adviser who co‑founded Sonoma Biotherapeutics and holds a Ph.D. from UCLA, shares the roughly $1.1–1.2 million prize with Brunkow (Institute for Systems Biology, Seattle) and Sakaguchi (Osaka University).