Scientists Mary Brunkow, Fred Ramsdell and Shimon Sakaguchi were honored with the 2025 Nobel Prize in Physiology and Medicine for “their discoveries concerning peripheral immune tolerance,” announced the Nobel Committee. “This year’s Nobel Prize in Physiology or Medicine focuses on how we control our immune system, so that we can fight any potential microbe while avoiding autoimmune diseases,” explained Marie Warren-Gash, professor at the Karolinska Institute.
BREAKING NEWS
The 2025 #NobelPrize in Physiology or Medicine has been awarded to Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi “for their discoveries concerning peripheral immune tolerance.” pic.twitter.com/nhjxJSoZEr— The Nobel Prize (@NobelPrize) October 6, 2025
The Nobel Prize winners in Medicine are selected by the Nobel Committee of Sweden’s Karolinska Institute and receive a monetary prize of 11 million Swedish kronor ($1.2 million), as well as a gold medal presented by the King of Sweden.
Nobel Prize in Medicine: What the three scientists discovered
The award winners identified “regulatory T cells,” which function as security guards of the immune system and prevent immune cells from attacking our own body.
“Their discoveries were crucial for understanding how the immune system works and why we don’t all develop serious autoimmune diseases,” said Olle Kämpe, chairman of the Nobel Committee.
Our immune system is an evolutionary masterpiece. Every day it protects us from the thousands of different viruses, bacteria and other microbes that attempt to invade our bodies. Without a functioning immune system, we would not survive.
One of the immune system’s marvels is its… pic.twitter.com/TzBWuIrTgn
— The Nobel Prize (@NobelPrize) October 6, 2025
