India, Oct. 6 -- Scientists Mary Brunkow, Fred Ramsdell and Shimon Sakaguchi were awarded the Nobel Prize in Physiology or Medicine for 'their discoveries concerning peripheral immune tolerance', the award-giving body said on Monday.

The awarded scientists identified the immune system's security guards, regulatory T cells, which prevent immune cells from attacking our own body.

"Their discoveries have been decisive for our understanding of how the immune system functions and why we do not all develop serious autoimmune diseases," says Olle Kampe, chair of the Nobel Committee.

In a statement issued by the award-giving body, it said Shimon Sakaguchi was swimming against the tide in 1995, when he made the first key discovery.

At the time...