Ralph Steinman is a cell biologist whose research focuses on the immune system including the human immune system in the setting of several diseases. He and his collaborators discovered a previously unknown class of immune cells, called dendritic cells. Dendritic cells are important and unique accessories in the onset of several immune responses including graft rejection, resistance to tumors, autoimmune diseases, and infections such as AIDS.

Ralph Steinman , born in Montreal, Canada, he received a B.S. degree, with honors, from McGill University in 1963, and an M.D., magna cum laude, from Harvard Medical School in 1968. After completing an internship and residency at Massachusetts General Hospital, he joined The Rockefeller University in 1970 as a postdoctoral fellow in the Laboratory Cellular Physiology and Immunology headed by Dr. Zanvil A.Cohn and the late James G. Hirsch. He was named Henry G. Kunkel Professor in 1995, and Director of the Chris Browne Center for Immunology and Immune Diseases in 1998.

Ralph Steinman is editor of the Journal of Experimental Medicine and serves on numerous editorial and advisory boards. He is a member of the National Academy of Sciences USA and has received many international awards including the Freidrich-Sasse, Emil von Behring, and Robert Koch Prizes, the Rudolf Virchow and Coley Medals.