“The discoveries provide many new perspectives”
The balance of the immune system is the focus of this year's Nobel Prize in Physiology or Medicine. The discoveries provide new perspectives on future treatments, says Marianne Quiding-Järbrink, professor of infectious immunology at the University of Gothenburg.
The 2025 Nobel Prize in Physiology or Medicine is awarded to Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi for groundbreaking discoveries concerning peripheral immune tolerance, which prevents the immune system from harming the body.
Every day, the immune system protects us from thousands of different microbes that try to invade our bodies. All of these microbes look different and many have developed similarities to human cells, as a kind of camouflage.
The question is what the immune system should attack and what it should protect. The fundamental discoveries awarded to the laureates concern something called peripheral immune tolerance. The laureates identified the immune system's sentinels, regulatory T cells, which prevent immune cells from attacking our own bodies.
Crucial for the immune balance
Marianne Quiding-Järbrink is a professor of infectious immunology at the Sahlgrenska Academy at the University of Gothenburg:
“Regulatory T cells are absolutely crucial for maintaining the balance of the immune system. We must be able to react to foreign substances, but not our own molecules. If the regulatory T cells do not function at all, you get very serious autoimmune diseases, that is, diseases where the immune system attacks our own tissue, even as a baby,” she says.
Regulatory T cells are also important for us not to react to harmless but foreign substances in our environment, from, for example, the normal flora of the intestine or substances that cause allergies. These are complex processes, explains Marianne Quiding-Järbrink, but the regulatory T cells are at the center of maintaining this tolerance, as it is called.
Better understanding of many diseases
Her own research group works, among other things, with regulatory T cells in tumors. There are often more regulatory T cells in the tumor than in the surrounding tissue. In the tumor, their activity can lead to tolerance to the tumor, and a reduced ability for the immune system to attack the tumor.
“As an immunologist, it is fantastic to see that the discovery of a central mechanism for maintaining balance in the immune system is being awarded the Nobel Prize. This knowledge has increased our understanding of many different diseases, but also of how the healthy immune system works,” says Marianne Quiding-Järbrink.
“The discoveries being praised have not yet led to any treatment that is used on a large scale, but they provide many new perspectives on what such therapies could look like, and several clinical trials are underway based on the laureates’ discoveries,” concludes Marianne Quiding-Järbrink.
They understood how the immune system is kept in check (The Nobel Assembly)
