Today would have been the 99th birthday of Frank Burnet, an Australian immunologist and virologist who explained how the body's immune system distinguishes between "self" and "nonself." Burnet studied viruses and bacteriophages (viruses that infect bacteria). In 1933, he developed a method for cultivating viruses on chicken embryos--an important breakthrough that greatly enhanced the ability of researchers to study viruses, which were notoriously difficult to grow in the lab. Burnet's subsequent studies led him to a theory about how the vertebrate immune system develops, acquiring the ability to recognize its own cells and to produce specific chemical antibodies against foreign invaders. For this work, Burnet received the Nobel Prize in physiology or medicine in 1960.
[Source: Emily McMurray, Ed., Notable Twentieth Century Scientists (Gale Research Inc., ITP, 1995).]