Sir Macfarlane Burnet

Sir Macfarlane Burnet (1899-1985), Australian virologist and cowinner, with British biologist Sir Peter Medawar, of the 1960 Nobel Prize in physiology or medicine, for their discoveries concerning acquired immunological tolerance.

Burnet was born in Traralgon, in the state of Victoria, Australia. He earned a B.S. degree and an M.D. degree from the University of Melbourne. He then became a pathologist at Royal Melbourne Hospital and a researcher at the Walter and Eliza Hall Institute for Medical Research. In 1926 Burnet traveled to London, England, to spend a year at the Lister Institute of Preventive Medicine. While in England, he earned a Ph.D. degree from the University of London. During a second trip, Burnet returned to England in 1932 to work at the National Institute for Medical Research, London, where he developed an improved technique for cultivating viruses using chick embryos. In 1944 he was appointed director of the Hall Institute of Medical Research in Melbourne and professor at the University of Melbourne.

Burnet explained how the body's immune system recognizes and attacks foreign invaders, such as viruses and bacteria, but ignores the body's own tissue. The immune system's ability to distinguish “self” from “non-self” tissue, suggested Burnet, arose during the late stages of embryonic development. He hypothesized that any substance present in the body before this critical period was recognized as self and tolerated, whereas any substance that presented an antigen (structures on foreign substances capable of initiating an immune response) not encountered during early development was subject to antibody assault and elimination.

Medawar proved Burnet correct in several experiments. In one, Medawar injected spleen cells from one strain of mouse into a mouse of another strain before that animal's immune system was fully developed. The injected mouse accepted a skin graft from mice of the other strain, when normally it should have rejected this foreign tissue. The work of Burnet and Medawar laid a foundation for the successful surgical transplantation of the liver, kidneys, pancreas, heart, skin, and other organs.

Burnet was knighted by King George VI of Britain in 1951, and received his nation's Order of Merit in 1958. He won the Royal Medal of the Royal Society in 1947, its Copley Medal in 1959, and the Albert Lasker Basic Medical Research Award in 1952.