Overview

• The Nobel Assembly at the Karolinska Institute named Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi the 2025 laureates in physiology or medicine on October 6.
• In 1995, Sakaguchi identified regulatory T cells that suppress harmful immune responses outside the thymus, establishing a peripheral mechanism of control.
• Brunkow and Ramsdell discovered FOXP3 in 2001 and showed that its mutations drive severe autoimmunity in mice and humans, with FOXP3 later confirmed as the master regulator of Treg development.
• The committee said the discoveries were decisive for understanding immune regulation and noted that multiple approaches derived from this field are being tested in patients.
• The three winners will share 11 million Swedish kronor, with affiliations cited including the University of Osaka, Princeton University, UCLA, the Institute for Systems Biology and Sonoma Biotherapeutics.