Overview

• The Nobel Assembly named Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi the 2025 laureates for defining how the immune system avoids attacking the body.
• Shimon Sakaguchi identified regulatory T cells in 1995, demonstrating a peripheral mechanism that restrains harmful immune responses outside the thymus.
• Mary E. Brunkow and Fred Ramsdell pinpointed the FOXP3 gene around 2001 as essential for Treg development, with mutations causing scurfy in mice and IPEX in humans.
• Later work connected FOXP3 directly to the Treg lineage, underpinning therapeutic strategies for autoimmune disease, cancer and transplant tolerance that the committee says are in clinical trials.
• The three winners will share 11 million Swedish kronor following the announcement in Stockholm, along with the traditional medal and diploma.