A San Diego researcher helped to discover one of “the greatest benefits on mankind," as Alfred Nobel said of his future prize winners.

Bruce Beutler of the Scripps Research Institute in San Diego shares the Nobel Prize for Medicine this year with two other scientists, the Nobel Prize committee announced Monday. The committee said Beutler is one of the “gatekeepers” of immune responses.

Beutler helped to develop vaccines for infectious diseases as chair of the Department of Genetics at Scripps. He is the fourth Scripps researcher to win the prize. Beutler received his undergraduate degree from UC San Diego, and returned to San Diego after receiving his M.D. from the University of Chicago.

He is responsible for identifying the receptors that inform the body when an infection is present, which helped him and his fellow researchers protect mammals against infections with the use of vaccines, according to a statement from Scripps. The same receptors also initiate inflammation and shock when an infection becomes widespread.

Beutler shares half of the prize with Jules A. Hoffmann. The two studied “the activation of innate immunity," the committee said. The other half goes to Ralph Steinman “for his discovery of the dendritic cell and its role in adaptive immunity.” All three scientists contributed to the creation of better vaccines that can help target tumors.

However the committee is unsure of whether Steinman can receive the prize – the Canadian-born scientist died three days before the announcement of the prize, which is not awarded posthumously.

Nobel committee member Goran Hansson said the Nobel committee didn't know Steinman was dead when it chose him as a winner and was looking through its regulations, according to MSNBC.

"It is incredibly sad news," Hansson said. "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."

Nobel officials said they believed it was the first time that a laureate had died before the announcement without the committee's knowledge.