The 2011 Nobel Prize in Physiology or Medicine was jointly awarded to three pioneers in immunology: one-half to Ralph M. Steinman, M.D. ’68, senior physician, Kunkel professor, and head of the Laboratory of Cellular Physiology and Immunology at Rockefeller University; and one-half jointly to Jules A. Hoffmann of Strasbourg University and Bruce A. Beutler of the Scripps Research Institute.
Breaking News Updates 10:35 a.m. and 11:20 a.m., 4:45 p.m.:
The New York Times is carrying an Associated Press report that Steinman died on September 30, of pancreatic cancer, possibly throwing the award of the Nobel Prize into doubt, as the Nobel Foundation rules prohibit posthumous awards; an update by Times science reporters, with an explanation of the scientific discoveries, appears here. Rockefeller University's announcement of the award and of Steinman's passing is here. The Nobel announcement that Steinman would be honored posthumously, in light of the unique circumstances surrounding the awarding of the prize and subsequent disclosure of his death.
According to the Nobel news release:
Ralph Steinman discovered, in 1973, a new cell type that he called the dendritic cell. He speculated that it could be important in the immune system and went on to test whether dendritic cells could activate T cells, a cell type that has a key role in adaptive immunity and develops an immunologic memory against many different substances. In cell culture experiments, he showed that the presence of dendritic cells resulted in vivid responses of T cells to such substances. These findings were initially met with skepticism but subsequent work by Steinman demonstrated that dendritic cells have a unique capacity to activate T cells.
Further studies by Steinman and other scientists went on to address the question of how the adaptive immune system decides whether or not it should be activated when encountering various substances. Signals arising from the innate immune response and sensed by dendritic cells were shown to control T cell activation. This makes it possible for the immune system to react towards pathogenic microorganisms while avoiding an attack on the body's own endogenous molecules.
According to the Rockefeller University description of Steinman's laboratory:
Dendritic cells, which were originally codiscovered by Dr. Steinman with Zanvil A. Cohn at Rockefeller, are pivotal to the adaptive and innate branches of the immune system. Dr. Steinman’s research focuses on the mechanisms employed by dendritic cells to regulate lymphocyte function in tolerance and immunity, as well as the use of dendritic cells to understand the development of immune-based diseases and the design of new therapies and vaccines.
The immune system contains a system of dendritic cells, which captures, processes and presents antigens and provides additional controls on the development of antigen-specific immunity and tolerance. Because of these functions, dendritic cells (DCs) are providing an important means to monitor and manipulate immune function in several disease states.
