Mary E. Brunkow and Fred Ramsdell of the United States and Japan's Shimon Sakaguchi won the Nobel Prize in Medicine on Monday for research into how the immune system is kept in check, the Nobel jury said.

The three were honoured "for their discoveries concerning peripheral immune tolerance," it said.

"Their discoveries have laid the foundation for a new field of research and spurred the development of new treatments, for example for cancer and autoimmune diseases," it added.

Winner hopes the award will advance patient care

Shimon Sakaguchi, the Japanese immunologist who won this year's Nobel Prize in medicine, said Monday he hoped the award will help further advance research and patient care.

"I sincerely hope that this award will serve as an opportunity for this field to develop further... in a direction where it can be applied in actual bedside and clinical settings," Sakaguchi, a 74-year-old distinguished professor at Osaka University, told a news conference.