12/13/2025
Congratulations to Dr. Mary Brunkow on receiving the 2025 Nobel Prize in Physiology or Medicine this week in Stockholm, Sweden! In her acceptance speech on Wednesday, Dr. Brunkow reflected: "As a woman in science I especially want to acknowledge those role models who gave me the courage and incentive to persevere. My hope is that I in turn can be that role model for my own daughters, who are just now launching out into the world, as well as for other young women who are excited about science."
Dr. Brunkow was honored for groundbreaking discoveries concerning peripheral immune tolerance, which prevents our immune system from attacking the body's own tissues. She identified the gene that controls regulatory T cells -- a previously unknown class of immune cells that act as security guards to keep harmful immune responses in check.
The American scientist shared the prize with Fred Ramsdell, also from the United States, and Shimon Sakaguchi from Japan, who made complementary contributions to understanding peripheral immune tolerance. The discoveries have laid the foundation for a new field of research and spurred the development of treatments for autoimmune diseases and cancer. As Olle Kämpe, chair of the Nobel Committee, explained, their research has "been decisive for our understanding of how the immune system functions and why we do not all develop serious autoimmune diseases."
Brunkow received her Ph.D. from Princeton University in 1991 in molecular biology and is currently a senior researcher at the Institute for Systems Biology in Seattle. Her Ph.D. adviser, former Princeton President Shirley M. Tilghman, described her as "incredibly bright" and "bold," noting that as a student, Brunkow was one of the first brave enough to tackle the mysterious H19 gene, which other scientists had dismissed as junk.
Brunkow and Ramsdell conducted their prize-winning research together at Celltech Chiroscience in 2001, when they identified a mutation in the FOXP3 gene in a mouse strain suffering from lethal autoimmunity. They explained why this specific type of mouse was particularly vulnerable to autoimmune diseases and showed that mutations in the human equivalent of this gene cause IPEX syndrome, a serious autoimmune disease. In 2003, Sakaguchi linked their findings to his earlier discovery of regulatory T cells from the 1990s, proving that the FOXP3 gene governs the development of these crucial immune regulators.
Brunkow, who is now the fourteenth woman to have won the Nobel Prize in Physiology or Medicine, described the regulatory T cells as "rare, but powerful, and they're critical for sort of dampening an immune response". She explained that these cells function as a braking system that prevents the body's immune system from tipping over into attacking itself. Their discoveries have led to potential treatments now in clinical trials for autoimmune diseases, cancer, and stem cell transplant complications.
This well-deserved recognition celebrates decades of groundbreaking work -- and shows the value of public investment in basic research -- that will benefit patients for generations to come!
To read Dr. Brunkow's complete acceptance speech, visit https://www.nobelprize.org/prizes/medicine/2025/brunkow/speech/
To introduce kids to many of the trailblazing women scientists who have been awarded the Nobel Prize, we highly recommend "Born Curious: 20 Girls Who Grew Up To Be Awesome Scientists" for ages 6 to 10 (https://www.amightygirl.com/born-curious), "She Can STEM: 50 Trailblazing Women in Science" for ages 7 to 12 (https://www.amightygirl.com/she-can-stem), and "Headstrong: 52 Women Who Changed Science – And The World" for ages 13 and up (https://www.amightygirl.com/headstrong-52-women)
For a picture book about the 2015 Nobel winner Tu Youyou, we recommend "Tu Youyou's Discovery: Finding a Cure for Malaria" for ages 5 and up at https://www.amightygirl.com/tu-youyou-s-discovery
For more books to introduce children and teens to inspiring female scientists from around the world, visit our blog post, "60 Children's Books to Inspire Science-Loving Mighty Girls" at https://www.amightygirl.com/blog?p=13914
If you'd like to encourage your children's interest in science, you can find many girl-empowering science toys and kits in our post, "Top Science Toys for Mighty Girls" at https://www.amightygirl.com/blog?p=10528
