Shimon Sakaguchi
Facts
Ill. Niklas Elmehed © Nobel Prize Outreach
Shimon Sakaguchi
Nobel Prize in Physiology or Medicine 2025
Born: 19 January 1951, Nagahama, Shiga, Japan
Affiliation at the time of the award: The University of Osaka, Osaka, Japan
Prize motivation: “for their discoveries concerning peripheral immune tolerance”
Prize share: 1/3
Work
The body’s powerful immune system must be regulated, or it may attack our own organs. In 1995, Shimon Sakaguchi discovered a class of immune cells, regulatory T cells, which protect the body from autoimmune diseases. Following Mary Brunkow and Fred Ramsdell’s discovery, six years later, that mutations in a gene cause autoimmune diseases, Sakaguchi was able to show that the gene controls the development of the cells he had identified. The discoveries can help the development of medical treatments for cancer and autoimmune diseases and lead to more successful transplantations.
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