Overview

• The Karolinska Institute announced the 2025 Nobel Prize in Physiology or Medicine on October 6, naming three laureates.
• The official prize motivation cites the discovery of peripheral immune tolerance.
• Shimon Sakaguchi identified regulatory T cells and clarified how they prevent the immune system from attacking the body's own tissues.
• Mary Brankow and Fred Ramsdell discovered a mutation in an autoimmune‑prone mouse strain, and Sakaguchi showed the mutation blocks regulatory T‑cell development.
• The award ceremony is scheduled for December 10 in Stockholm with a prize of 11 million Swedish kronor.