Elie Metchnikoff (1845-1916), Russian biologist and Nobel laureate. Metchnikoff, also known as Ilya Ilyich Mechnikov, is best known for his pioneering research into the immune system, for which he won the Nobel Prize in Physiology or Medicine in 1908. He discovered phagocytosis while working at a private laboratory in Messina, Sicily, Italy. This is the process of cells engulfing large particles (such as bacteria or dead cells), and one of the ways that the white blood cells of the immune system fight disease.