3 get Nobel Prize in medicine for work on immunity

Discoveries could spur new treatments for autoimmune diseases, cancer

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Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi have won the Nobel Prize in medicine for their discoveries concerning peripheral immune tolerance.

Peripheral immune tolerance is one way the body helps keep the immune system from getting out of whack and attacking your own tissues instead of foreign invaders.

Last year's prize was shared by Americans Victor Ambros and Gary Ruvkun for their discovery of microRNA, tiny bits of genetic material that serve as on and off switches inside cells that help control what the cells do and when.