Seattle scientist Mary Brunkow wins Nobel Prize for immune system research

A Seattle scientist, Mary E. Brunkow, was named among three Nobel Prize winners Monday for their advancements and discoveries related to the human immune system.

Brunkow, Fred Ramsdell, and Dr. Shimon Sakaguchi won the Nobel Prize in Physiology or Medicine, the first of many 2025 Nobel Prize announcements made at the Karolinska Institute in Stockholm, Sweden, according to The Associated Press.

“Their discoveries have been decisive for our understanding of how the immune system functions and why we do not all develop serious autoimmune diseases,” said Olle Kämpe, Chair of the Nobel Prize Committee.

Brunkow, 64, is a senior program manager at the Institute for Systems Biology in Seattle. Ramsdell, 64, is a scientific adviser for Sonoma Biotherapeutics in San Francisco. Sakaguchi, 74, is a professor at the Immunology Frontier Research Center at Osaka University in Japan.

Seattle Nobel Prize winners’ first reaction to the victory

Brunkow was in her Seattle home when she learned of her victory from a photographer with The Associated Press who arrived early Monday morning. She said she ignored a call from the Nobel Prize Committee earlier, thinking, “That’s spam of some sort.”

“When I told Mary she won, she said, ‘Don’t be ridiculous,'” Ross Colquhoun, Brunkow’s husband, said.

The three Nobel Prize winners have been awarded 11 million Swedish kronor, nearly $1.2 million, to be split amongst the trio.

The research began with a key discovery by Sakaguchi in 1995, which uncovered a previously unknown class of immune cells that protect the body from autoimmune diseases.

Years later, Brunkow and Ramsdell made the other pivotal discovery in 2001, finding that a specific mouse strain was vulnerable to autoimmune diseases. The two discovered that the mice have a mutation in a gene they named “Foxp3.” They later demonstrated that mutations in the human equivalent of the gene can lead to a severe autoimmune disease, IPEX.

Two years later, Sakaguchi linked the two discoveries, proving that the Foxp3 gene governs the development of the cells he identified in his 1995 discovery. The cells, now known as T Cells, monitor other immune cells to ensure that our immune system tolerates our own tissues.

Other Nobel Prizes to be announced

The physics prize winner will be announced on Tuesday, the chemistry prize winner on Wednesday, and the literature prize winner on Thursday. Additionally, the Nobel Peace Prize will be announced on Friday, and the Nobel Memorial Prize in economics will be announced on Oct. 13.

All Nobel Prize winners will be invited to the award ceremony on Dec. 10, the anniversary of the death of Alfred Nobel, the founder of the achievement. Nobel was a Swedish industrialist who invented dynamite. He died in 1896.

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