Americans win Nobel Prize in medicine for work on human immune system

A trio of scientists — two of them American and one Japanese — have won the Nobel Prize in medicine for their discoveries concerning peripheral immune tolerance, a mechanism by which the body helps prevent itself from attacking its own tissues instead of foreign invaders

A trio of scientists — two of them American and one Japanese — have won the Nobel Prize in medicine for their discoveries concerning peripheral immune tolerance, a mechanism by which the body helps prevent itself from attacking its own tissues instead of foreign invaders.

Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi will share the prize for discoveries that "launched the field of peripheral tolerance, spurring the development of medical treatments for cancer and autoimmune diseases,” the Nobel Assembly said in a news release. The trio will share the prize money of 11 million Swedish kronor (nearly $1.2 million).

"This may also lead to more successful transplantations. Several of these treatments are now undergoing clinical trials," it added.

Autoimmune diseases can be triggered when T cells, our body's primary defense mechanism against harmful pathogens, malfunction.

Together, the trio's discoveries lay a crucial foundation for understanding another way our immune system keeps itself in check, known as peripheral tolerance — a key to understanding why some people suffer from certain autoimmune diseases while others don't.