On October 6, 2025, Mary E. Brunkow, Fred Ramsdell, and Shimon Sakaguchi were awarded the Nobel Prize in Science for their discoveries on the immune system. Both Brunkow and Ramsdell are 64 years old and reside in the United States. Sakaguchi, on the other hand, is 74 years old and resides in Japan. Brunkow is currently working at the Institute for Systems Biology. Ramsdell is currently working for Sonoma Biotherapeutics, a Seattle-based start-up. Sakaguchi continues to work at Osaka University as a professor. The scientists were surprised when they found out they had won this award, with Brunkow saying that she had ignored earlier calls from the Nobel Committee, thinking that they were scams. They will share the 11 million Swedish kronor, which is roughly $1.1 million in prize money.

Before this discovery, immunologists did not understand the complexity of the body, and they wondered how the body’s immune system knew not to attack itself. This trio of scientists discovered the reason why the immune system knows how to attack malicious bacteria and viruses, and not our bodies, by uncovering a key pathway our body uses to keep the immune system in check, called peripheral immune tolerance. Experts consider this finding critical to understanding autoimmune diseases such as Type 1 diabetes, Crohn’s disease, and Lupus.

These scientists identified a key feature of how the immune system functions and keeps itself in check: regulatory T-cells. These cells prevent other immune cells from harming our bodies. Other scientist have based their own research on the discovery of regulatory T-cells. They are using this to discover better treatments for autoimmune diseases, to improve organ transplant success, and to enhance the body’s ability to fight against cancer. Scientists are doing this through using T-cells, which are also known as T-regs, treatments instead of therapies like chemotherapy, which weakens the immune system. This has not happened yet, but it is inevitable. This is just the tip of the iceberg. 

The American Association of Immunologists said that the winners’ work “has fundamentally reshaped our understanding of immune balance.” Their findings will prompt researchers to consider what in the past has never been seen as possible. Now, new scientists are excited to conduct more research since many illnesses need further research and more treatments. Who knows how many different illnesses can be treated and cured due to these findings?