Important personalitiesBack

Niels Kaj Jerne (December 23, 1911 – October 7, 1994) was a Danish immunologist. He shared the Nobel Prize in Physiology or Medicine in 1984 with Georges J. F. Köhler and César Milstein "[f]or theories concerning the specificity in development and control of the immune system and the discovery of the principle for production of monoclonal antibodies".

Jerne is known for three significant ideas. Firstly, instead of the body producing antibodies in response to an antigen, Jerne postulated that the immune system already has the specific antibodies it needs to fight antigens. Secondly, it was known that the immune system learns to be tolerant to the individual's own self. Jerne postulated that this learning takes place in the thymus. Thirdly, it was known that T cells and B cells communicate with each other. Jerne's network theory proposed that the active sites of antibodies are attracted to both specific antigens (idiotypes) and to other antibodies that bind to the same site. The antibodies are in balance, until an antigen disturbs the balance, stimulating an immune reaction.


Research positions

From 1943 to 1956 Jerne was a research worker at the Danish National Serum Institute and during this time he formulated a theory on antibody formation. It is said that Jerne got his revolutionary scientific idea while bicycling across the Langebro bridge in Copenhagen on his way home from work. The antibody formation theory gave Jerne international recognition and in 1956 Jerne went to work for the World Health Organization in Geneva, where he served as the Head of the Sections of Biological Standards and of Immunology. He held this post for six years until moving to the United States and the University of Pittsburgh in 1962 to work as Professor of Microbiology and Chairman of the Department of Microbiology for four years. Jerne continued to do work for the World Health Organization as a member of the Expert Advisory Panel of Immunology from 1962 and onwards.

In 1966 Jerne moved back to Europe and took up the position of Professor of Experimental Therapy at the Johann Wolfgang Goethe University in Frankfurt. From 1966 to 1969 he was the Director of the Paul-Ehrlich-Institut, also in Frankfurt. In 1969 Jerne again switched jobs, this time to Basel in Switzerland, where he was the Director of the Basel Institute for Immunology until his retirement in 1980. During the 1970s and 1980s Jerne was a pioneer in the development of immune network theory.

According to Jerne's biographer Thomas Söderqvist, Jerne was not a bench scientist, could not pipette accurately, and did not enjoy experimental work. His Nobel Prize was awarded for theories, rather than discoveries. Jerne developed the "natural selection theory of immunology," proposed by Paul Ehrlich 50 years earlier, although he was missing the clonal selection element proposed by David Talmage and then by Frank Macfarlane Burnet. James Watson told Jerne that his theory "stinks."