Elie Metchnikoff

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Elie Metchnikoff


Russian Biologist, Bacteriologist and Pathologist

Noble laureate Elie Metchnikoff made significant contributions to biology and medicine. He won the Nobel Prize in medicine (with Paul Ehrlich) in 1908 for his theory of immunity. Metchnikoff was the first to discover that immunity stems from the action of white corpuscles in the blood that devour foreign bodies such as bacteria, and that inflammation in infected parts of the body is the tissue's defensive reaction to irritation and germs. Metchnikoff also demonstrated key similarities in the embryonic development of invertebrate and vertebrate animals and is considered one of the founders of comparative pathology and evolutionary embryology.

Metchnikoff was born on May 15, 1845, in the western area of the Russian Empire known as Ukraine. The son of a noble landowner, he demonstrated from an early age a passionate interest in science. He used his first microscope at age fifteen, and thereby began a lifetime study of microorganisms. By the time he was nineteen, he was a published author and a university graduate. Upon completion of Kharkov University in 1864, he went abroad to work with leading scientists in Germany and in Italy, where he helped develop a new field—comparative evolutionary embryology.

After receiving both a master's and a doctoral degree from St. Petersburg University, Metchnikoff taught zoology from 1870 to 1882 at the University of Novorossiia in Odessa. In 1886 Metchnikoff was appointed director of the first Russian bacteriological station, an institution established to study and prepare inoculations for infectious diseases such as rabies, tuberculosis, and cholera. Two years later Metchnikoff joined the Pasteur Institute, which was founded in Paris by the famous bacteriologist Louis Pasteur (1822-1895), and here he spent the rest of his life teaching and conducting research.

Metchnikoff devoted much of his time after 1881 to developing and then defending his groundbreaking phagocytic, or cellular, theory of immunity. Contrary to established theories, which linked immunity with chemical properties of blood serum, Metchnikoff demonstrated that it was phagocytosis—the absorption and digestion of microbes by amoeba-like specialized cells (phagocytes) in animals—along with inflammation that produce recovery and immunity from disease. Despite early opposition, Metchnikoff's theory is now a basic principle of immunology; moreover, his findings deepened understanding of how and why natural and artificial vaccinations work.

Metchnikoff believed deeply in public service and public health. He gave lectures and wrote popular articles on hygiene and medicine. He developed broad research interests, including a study of the aging process and senility, and contributed to the development of gerontology in Russia. Metchnikoff proposed that old age and death occur prematurely in humans due to the intoxication of the body by intestinal bacteria, and he recommended that people sterilize food, limit meat consumption, and use fermented milk products. His studies on aging led him to investigate arteriosclerosis and diseases caused by intestinal microbes, including typhoid fever, infantile cholera, and syphilis. In 1903 he and a fellow researcher at the Pasteur Institute, M. Roux, were the first to produce syphilis experimentally in monkeys, which enhanced the ability of researchers to diagnose the disease and test potential treatments and vaccines. The study of syphilis, which until this time had remained purely clinical, could now become an experimental science.

While abroad Metchnikoff stayed in close contact with Russian scientists, and many leading Russian microbiologists and epidemiologists came to the Pasteur Institute for training. He is credited with building the first Russian school of microbiologists, immunologists, and pathologists. In addition to the Nobel Prize, Metchnikoff received numerous awards, including an honorary doctorate from Cambridge University, and was elected to various international academies of science, scientific societies, and institutes.

On July 15, 1916, Metchnikoff died in Paris at the age of seventy-one.