STOCKHOLM: US scientists Mary Brunkow and Fred Ramsdell and Shimon Sakaguchi from Japan won the 2025 Nobel Prize for medicine Monday for work shedding light on how the immune system spares healthy cells, creating openings for possible new cancer and autoimmune disease treatments.Their work laid the foundation for a new research field identifying so-called regulatory T cells, “the immune system’s security guards” that prevent the body from harming itself, the Nobel committee said.The discoveries relate to peripheral immune tolerance, or “how we keep our immune system under control so we can fight microbes and still avoid autoimmune disease”, said Marie Wahren-Herlenius, professor at Sweden’s Karolinska Institute, whose Nobel panel selects the winners.The institute’s Thomas Perlmann said therapies based on the discoveries had yet to win market clearance but over 200 trials on humans were ongoing. AgenciesSakaguchi says time will come when cancer is no longer scary, but curableSakaguchi, a professor at Osaka University, told a press conference in Japan that he hoped the award would “serve as an opportunity for this field to develop further… in a direction where it can be applied in actual bedside and clinical settings”. The Nobel committee was unable to reach the two US-based laureates to break the news to them in person.Brunkow is senior programme manager at the Institute for Systems Biology in Seattle, while Ramsdell is scientific adviser at Sonoma Biotherapeutics in San Francisco.Sakaguchi got a congratulatory phone call from Japanese PM Shigeru Ishiba during the presser, who asked him how effective immunotherapy could be for cancer treatment in the future. “I believe the time will come when cancer is no longer a scary disease, but a curable one,” said Sakaguchi.The Nobel jury earlier said, “The hope is to be able to treat or cure autoimmune diseases, provide more effective cancer treatments and prevent serious complications after stem cell transplants.”Brunkow later told the Nobel Foundation she had been sleeping when the call came. “My career in science has changed quite a bit since that work was done, and I don’t actually even work in that particular field anymore,” she said in an interview on the foundation’s website. “It’s an honour to have been a part of that.”Ramsdell had still not been contacted hours after the announcement.
