Karl Landsteiner was an Austrian-American biologist, physician, and immunologist. He emigrated with his family to New York in 1923 at the age of 55 for professional opportunities, working for the Rockefeller Institute.
He had distinguished the main blood groups in 1901, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the blood. In 1937, with Alexander S. Wiener, he identified the Rhesus factor, thus enabling physicians to transfuse blood without endangering the patient's life. With Constantin Levaditi and Erwin Popper, he discovered the polio virus in 1909. He received the Aronson Prize in 1926. In 1930, he received the Nobel Prize in Physiology or Medicine. He was posthumously awarded the Lasker Award in 1946, and has been described as the father of transfusion medicine.