Born: 29 October 1920, Caracas, Venezuela
Died: 2 August 2011, Boston, MA, USA
Affiliation at the time of the award: Harvard Medical School, Boston, MA, USA
Prize motivation: "for their discoveries concerning genetically determined structures on the cell surface that regulate immunological reactions"
Prize share: 1/3
Our immune system rejects damaged or abnormal cells, allowing our bodies to function properly. During the 1960s Baruj Benaceraff showed through studies of guinea pigs that the immune system's reaction to certain substances is determined by genes that exist in a certain area on a certain chromosome. George Snell and Jean Dausset had previously shown that genes that govern rejection of foreign cells exist in similar areas in mice and in people. Baruj Benaceraff's results shed light on the interplay among different parts of the immune system.