October 6, 2025
UW alum Mary E. Brunkow awarded the 2025 Nobel Prize in Physiology or Medicine
Mary Brunkow sitting at her dining table at 4:30 a.m. Pacific Time during the first-reaction interview.Ross Colquhoun
The Nobel Assembly at the Karolinska Institute on Monday awarded the 2025 Nobel Prize in Physiology or Medicine jointly to Mary E. Brunkow — an alum of the University of Washington — along with Frederick J. Ramsdell and Shimon Sakaguchi “for groundbreaking discoveries concerning peripheral immune tolerance that prevents the immune system from harming the body.”
Brunkow is a senior program manager at the Institute for Systems Biology in Seattle, and received her bachelor’s degree in molecular and cellular biology from the UW in 1983. Brunkow went on to earn her doctoral degree from Princeton University in 1991.
Brunkow’s award-winning research comes from when she was working with Ramsdell at Celltech Chiroscience in Bothell, Washington. The two researchers identified a mutation in a gene called foxp3, which makes mice susceptible to a type of skin disorder. Mutations in the human equivalent of the foxp3 gene are also responsible for IPEX syndrome, which has symptoms including intestinal problems, diabetes and scaly, itchy skin.
Sakaguchi later described the role of the wild-type foxp3 gene in the development of certain white blood cells known as regulatory T cells. These cells, which Sakaguchi discovered, keep other T cells from mistakenly attacking normal tissues. Regulatory T cells also call a cease-fire once the body gets an infection under control.
These findings provided insights into the concept of “peripheral immune tolerance,” which keeps the immune system in check by avoiding autoimmune responses that can damage healthy tissues. The field, which was honored by this year’s Nobel Prize, holds promise in advancing therapies for cancers and autoimmune diseases, and for improvements in treatments to reduce transplant rejection.
Brunkow did not immediately know that she had been awarded the Nobel Prize. She only found out when the family dog alerted them to someone at their door this morning — it was an AP reporter who wanted to interview her.
Brunkow is the sixth UW alumnus to win a Nobel Prize after Jeffrey C. Hall, George Hitchings, George Stigler, Martin Rodbell and Linda B. Buck. Hitchings, Stigler and Buck all earned their bachelor’s degrees from UW, graduating in 1927, 1931 and 1975, respectively. Rodbell and Hall earned their doctoral degrees from UW in 1954 and 1971, respectively.
The previous Nobel prize for a scientist working in Seattle went to David Baker, professor of biochemistry at the UW School of Medicine and director of the UW Medicine Institute for Protein Design. Baker received the 2024 Nobel Prize in chemistry.
Tag(s): College of Arts & Sciences • Department of Biology • Mary Brunkow • Research Makes America