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STOCKHOLM, Oct 3 (Reuters) - Three scientists who uncovered
key secrets of how the body's immune system works have won the
2011 Nobel prize for medicine or physiology, the prize-awarding
institute said on Monday.
Sweden's Karolinska Institute said in a statement that the
prize went to U.S. scientist Bruce Beutler, Luxembourg-born
Jules Hoffmann, based in France, and Canadian-born Ralph
Steinman, based in the United States.
"This year's Nobel Laureates have revolutionised our
understanding of the immune system by discovering key principles
for its activation," the institute said.
Beutler and Hoffmann shared one half of the prize of 10
million Swedish crowns ($1.46 million) and Steinman won the
The work of the three scientists has been pivotal to the
development of improved types of vaccines against infectious
diseases and novel approaches to fighting cancer. The research
has helped lay the foundations for a new wave of so-called
"therapeutic vaccines" that stimulate the immune system to
Better understanding of the complexities of the body's
immune system has also provided clues for treating inflammatory
diseases, such as rheumatoid arthritis, where the components of
the self-defence system end up attacking the body's own tissues.
Medicine is traditionally the first of the Nobel prizes
awarded each year. Prizes for achievements in science,
literature and peace were first awarded in 1901 accordance with
the will of dynamite inventor and businessman Alfred Nobel.
The award citation said scientists had long been researching
the immune response by which man and other animals defend
themselves against attack by bacteria and other microorganisms.
Beutler and Hoffmann discovered receptor proteins that can
recognize microorganisms attacking the body and which activate
"innate immunity", the first step in the body's immune response,
the statement said.
"Ralph Steinman discovered the dendritic cells of the immune
system and their unique capacity to activate and regulate
adaptive immunity, the later stage of the immune response during
which microorganisms are cleared from the body," it added.
($1 = 6.868 Swedish Crowns)
(Reporting by Patrick Lannin and Anna Ringstrom in Stockholm
and Ben Hirschler in London; Editing by Alastair Macdonald)
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