Nobel Prize in Medicine 2025 Honors Discoverers of the Mechanism of 'Self-Regulation' in the Immune System

Three scientists have won the Nobel Prize in Physiology or Medicine for 2025, in recognition of their discovery of critical mechanisms that enable the immune system to restrain itself and prevent it from attacking healthy body tissues, known as peripheral immune tolerance.
The Nobel Committee announced that the prize was awarded to:
Mary E. Branco from the Institute of Systems Biology in Seattle (United States),
Fred Ramsdell from Sonoma Biotherapeutics in San Francisco,
Shimon Sakaguchi from Osaka University in Japan.
The committee praised the research that led to a "deeper understanding of how the immune system balances protecting the body from infection and preventing excessive responses that could cause autoimmune diseases."
These discoveries open the door to the development of new treatments for diseases such as type 1 diabetes, multiple sclerosis, and cancers, where the mechanisms of 'immune checkpoints' can be utilized to control immune responses.
This achievement is considered a significant milestone in the field of modern immunology, as it highlights the intricate complexity of the immune system and its role in maintaining the body's balance.