Shimon Sakaguchi

Facts

Shimon Sakaguchi

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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