An appreciation of Ralph Marvin Steinman (1943–2011).

Ralph Steinman, an editor at the Journal of Experimental Medicine since 1978, shared the 2011 Nobel Prize in Physiology or Medicine for his discovery of dendritic cells (DCs) and their role in immunity. Ralph never knew. He died of pancreatic cancer on September 30, 3 days before the Nobel announcement. Unaware of his death at the time of their announcement, the Nobel Committee made the unprecedented decision that his award would stand. Ralph was the consummate physician-scientist to the end. After his diagnosis, he actively participated in his 4.5 years of treatments, creating experimental therapies using his own DCs in conjunction with the therapies devised by his physicians, all the while traveling, lecturing, and most of all pursuing new investigations in his laboratory. For 38 years—from his discovery of DCs to his Nobel Prize—Ralph pioneered the criteria and methods used to identify, isolate, grow, and study DCs. He and his colleagues demonstrated that DCs are initiators of immunity and regulators of tolerance. In his most recent studies, Ralph was harnessing the specialized features of DCs to design improved vaccines. The following synopsis describes some of his seminal discoveries.