The discoveries have served as the foundation for a new generation of vaccines either in clinical trials or on the horizon, researchers say.
Two scientists – Bruce Beutler of the Scripps Research Institute in La Jolla, Calif., and Jules Hoffmann, who until 2009 headed a lab at the Institute for Molecular Cell Biology in Strasbourg, France – will split half of the 10 million Swedish krona (about $1.46 million US) purse.
The duo was recognized for work conducted in the mid to late 1990s that uncovered genes bearing the blueprint for proteins that sense the presence of invading microorganisms linked to diseases. These sensors trigger an organism's initial immune response.
Dr. Hoffmann identified the mechanism in fruit flies. Dr. Beutler uncovered a similar mechanism in mammals.
The second half of the purse was awarded to Ralph Steinman, until three days ago the director of Rockefeller University's Center for Immunology and Immune Diseases. In 1973, he found a new type of cell that triggers and regulates the second stage of an organism's immune response, which aims to rid the human body of marauding microbes.
Following the announcement of Monday's award, news surfaced that Dr. Steinman passed away three days ago. The award stiplates that the recipients must be alive at the time the winners are announced.
According to Rockefeller University, Steinman's family had not contacted the university about his death until Monday.
"It is incredibly sad news," Nobel committee member Goran Hansson told the AP. "We can only regret that he didn't have the chance to receive the news he had won the Nobel Prize. Our thoughts are now with his family."
For Beutler and Hoffmann, the award is the latest addition to the accolades they have received from the scientific community in recent years.
In 2007, the two won Italy's Balzan Prize in Epigenetics for their work. Earlier this year, they shared Hong Kong's Shaw Prize with Yale University's Ruslan Medzhtov for the insights the trio's work provides on the immune system.
The Nobel Prize in Medicine or Physiology is the first of six annual prizes to be awarded over the next seven days. This week, it will be followed by the prizes for physics, chemistry, literature, and the peace prize. On Oct. 10, the prize for economics will be announced.
The recipients will receive their awards on Dec. 10 at a ceremony in Stockholm.
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