Niels Jerne

Niels Kaj Jerne was born on December 23, 1911 in London, England. His family had lived on the Danish island Fano since the seventeenth century. His father, Hans Jerne and mother, Else Lindberg, moved to London, England in 1910, the year before his birth. During the World War I the family lived in Rotterdam, Netherlands, where he spent his youth and earned his bachelors degree in 1928. After spending two years studying physics in Lieden, he moved to Copenhagen where he studied medicine, earning a medical degree in 1947 and a doctorate in 1951.

From 1943 to 1956 Jerne worked at the Danish National Serum Institute. During this time he proposed the theory of antibody selection, that the immune system produced a multitude of antibodies and through interactions with antigen (a molecule recognized by antibodies) antibodies were selected and the immune system produced more of them. This theory was later refined by David Talmadge and Frank Macfarlane Burnet, who separately proposed the genetic mechanism by which antibody producing cells each pick the DNA that will code for the cell's antibodies. Antibody producing cells are part of the body's humoral immune response. Antibodies are protein molecules that recognize and bind a particular antigen. Because they have multiple binding sites antibodies, when bound to antigen, can form large clumps. In a addition to their binding sites, antibodies have a site recognized by phagocytic cells. When large clumps of antibody/antigen complex form these recognition sites serve to signal phagocytic cells to devour it.

Starting in 1956 Jerne worked for the World Health Organization in Geneva. In 1962 he moved to the University of Pittsburg in Pittsburgh, Pennsylvania. From 1966 to 1969 he was director of the Paul-Erlich Institute and from 1969 to his retirement in 1980 he ran his own institute as director of the Basel Institute of Immunology. While there Jerne was the first to speculate about the role of the major histocompatability complex. This is a protein complex produced by cells that presents antigens on the cells surface. This is recognized by T-lymphocytes. When the antigen is recognized it means that it is foreign to the body and stimulates an immune response from the T-cell. T-cells then activate and secrete chemicals to stimulate the immune response.

Jerne's other major contribution to immunology was the idea that the immune system functions as a network, each part influencing the others. This is how the immune system is viewed today, where immune cells secrete an array of cytokines, hormones that influence the functions of the other cells of the body and the immune system. This paradigm has allowed immunologists to better understand immune cell dysfunction and the effects of the viral infection of immune cells in HIV infection. For his contributions to our understanding of immunology Jerne was awarded the 1984 Nobel Prize in Medicine, with Georges Kohler and Cesar Milstein.

Jerned died on October 7, 1994.


References:

Hoffmann, Geoffrey, W.; "Niels Jerne, Immunologist: 1911-1994"; Vaccine Research (1994)3

Nobel autobiography

Neils Gerne Wikipedia entry