Overview

• The Nobel Committee awarded the 2025 Physiology or Medicine prize to Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi for discoveries concerning peripheral immune tolerance.
• In 1995, Sakaguchi identified a previously unknown class of regulatory T cells that protect against autoimmune disease.
• In 2001, Brunkow and Ramsdell tied mutations in the Foxp3 gene to severe autoimmunity in mice and to the human disorder IPEX.
• Later research showed that Foxp3 directs the development of regulatory T cells, linking the genetic mechanism to the cell type.
• The discoveries founded a field driving new treatments for autoimmune disease, cancer and transplantation, with many approaches now in clinical trials.