Nobel prize in medicine awarded to scientists for immune system research

Mary E Brunkow, Fred Ramsdell and Shimon Sakaguchi win for work on preventing immune system harming body

The Nobel prize in physiology or medicine 2025 has been awarded to three scientists for their work on how the immune system is prevented from attacking the body.

Mary E Brunkow, now at the Institute for Systems Biology in Seattle, Fred Ramsdell, now at Sonoma Biotherapeutics in San Francisco, and Shimon Sakaguchi, now at Osaka University in Japan, have been awarded the prize “for their discoveries concerning peripheral immune tolerance”.

Announced on Monday by the Nobel assembly at the Karolinska Institute in Stockholm, Sweden, the winners will share a prize of 11m Swedish kronor (about £871,400).

At the time of the announcement, Prof Thomas Perlmann, secretary-general of the Nobel assembly, revealed he had managed to reach only Sakaguchi.