Three scientists awarded Nobel Prize in medicine for immune system research

Osaka University professor Dr. Shimon Sakaguchi receives flowers at a news conference in Suita, near Osaka, on Monday, after he won the Nobel Prize in medicine.

From insulin to the molecular machinery that regulates our genes, the subtle science of the human body has been a source of wonder – and Nobel Prizes – for more than a century.

On Monday, the Nobel Assembly at the Karolinska Institute in Sweden once again gave basic biomedical research a nod of approval by recognizing the discovery of peripheral immune tolerance, a way in which the body keeps its internal defenses from attacking its own tissues.

Three scientists – Mary E. Brunkow and Fred Ramsdell of the United States, and Shimon Sakaguchi of Japan –were awarded the 2025 Nobel Prize in Physiology or Medicine for uncovering the p