The Nobel Prize for 2025 in Physiology or Medicine has been awarded to the trio Mary E. Brunkow, Fred Ramsdell, and Shimon Sakaguchi for “their discoveries concerning peripheral immune tolerance,” the Royal Swedish Academy of Sciences announced in Stockholm on Monday. The three researchers will split a prize of 11 million Swedish Kroner, which is around $1.17 million.

The laureates identified the immune system’s security guards, regulatory T cells, which prevent immune cells from attacking our own body, according to a press release by the academy.

Shimon Sakaguchi, born in 1951, is an expert in immunology at Osaka University, Japan, and is a distinguished professor at the Immunology Frontier Research Center.

Mary E. Brunkow, 64, researches genomics and autoimmune diseases at the Institute for Systems Biology, Seattle.

Fred Ramsdell, 64, is a scientific advisor at Sonoma Biotherapeutics, a biotechnology company in San Francisco.

Brunkow and Ramsdell performed the research in the Seattle area for Celltech Chiroscience, a British-owned biotechnology company at the time. The discoveries launched the field of peripheral tolerance. Their work is now being used to develop new treatments for autoimmune diseases and cancer.

Source: The Week - October 6, 2025