Three scientists were awarded the Nobel Prize in Physiology or Medicine for discoveries on how the immune system self-regulates, which have led to potential therapies for cancer and autoimmune diseases.

Mary Brunkow, Fred Ramsdell and Shimon Sakaguchi will share the 11 million-krona ($1.2 million) award, the Nobel Assembly at Karolinska Institutet in Stockholm said in a statement Monday. Brunkow and Ramsdell are based in the U.S., while Sakaguchi hails from Japan.

The scientists’ work laid the foundation for a new field of research and potential treatments by identifying “the immune system’s security guards” that prevent the body from harming itself, the Nobel Committee said.

The work took place over several decades. Sakaguchi paved the way with his discovery of a new class of T cells — the white blood cells that play a crucial role in our defenses. These regulatory T cells help turn the immune response down after it eliminates an invader and prevent other T cells from attacking healthy ones.

Brunkow and Ramsdell built on his findings as they looked for explanations to autoimmune diseases. Working together at Celltech Chiroscience, a biotech in Washington state, the pair found a faulty gene on mice with severe autoimmune disease caused by a mutation after radiation. They named it Foxp3, and it turned out to be key to regulating T cell function as well as the cause of a rare inherited autoimmune disease called IPEX syndrome. Two years later, Sakaguchi was able to show that the Foxp3 gene controls the development of regulatory T cells.

Potential treatments

The findings spurred the development of potential new medical treatments. “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,” according to the Nobel Committee.

Researchers are looking at ways to dismantle a wall of regulatory T cells that shields cancer tumors from the immune system, while in autoimmune diseases, they’re trying to promote the formation of more regulatory T cells.

Brunkow, who was born in 1961, has worked at Institute for Systems Biology in Seattle since 2009 on a number of projects, including family genomics in a wide variety of disease areas, the systems biology of Lyme disease and sepsis biomarkers, according to the non-profit biomedical research organization’s website. She holds a PhD in molecular biology from Princeton University.

Ramsdell, 64, is a founder and former chief scientific officer of Sonoma Biotherapeutics Inc with a doctoral degree in microbiology and immunology from the University of California, Los Angeles. His previous employers include Darwin Molecular and Novo Nordisk A/S, the Danish maker of blockbuster obesity and diabetes medications. At Novo, Ramsdell helped establish a new Inflammation Research Center in Seattle.

Sakaguchi, 74, is an immunologist at Osaka University’s Immunology Frontier Research Center. He has a PhD from Kyoto University in Japan and has studied at Johns Hopkins University and Stanford University.

Annual prizes for achievements in physics, chemistry, medicine, literature and peace were established in the will of Alfred Nobel, the Swedish inventor of dynamite, who died in 1896. A prize in economic sciences was added by Sweden’s central bank in 1968.

Last year’s medicine Nobel was awarded to two American scientists for their discovery of a fundamental principle governing how gene activity is regulated via tiny RNA molecules. Other notable discoveries to have earned the honors include insulin in 1923, penicillin in 1945 and the molecular structure of DNA in 1962.

The laureates are announced through Oct. 13 in Stockholm, with the exception of the Nobel Peace Prize, whose recipients are selected on Friday by the Norwegian Nobel Committee in Oslo.

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