The Russian physiologist and bacteriologist Élie Metchnikoff (1845-1916) is best noted for his phagocytic theory of immunity. He also made contributions to comparative pathology, evolutionary embryology, and microbiology.

On May 15, 1845, Élie Metchnikoff was born in the Ukrainian village of Ivanovka. At the age of 17 he entered Kharkov University; the following year he produced his first scientific work, "Some Facts from the Life of Infusoria"; and he completed his studies in the natural sciences by the time he was 19. In 1864 he left for Germany to expand his knowledge of zoology, studying under Rudolf Leuckart, the father of modern parasitology.

Metchnikoff went on to the universities of Göttingen and Munich. He returned to Russia in 1867, received his master's degree in zoology after presenting his thesis, The History of the Embryonal Development of Sepiola, and was appointed dozent at Novorossiisk University in Odessa. In 1868 he successfully defended...