Medicine and chemistry
Landsteiner graduated in medicine at Vienna in 1891, pursued further training in chemical laboratories and returned to research in pathology and immunology. He applied chemical methods to questions about the specificity of antigens, antibodies and sera.
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Agglutination and blood groups
Mixing serum and red blood cells from different people produced agglutination in some combinations but not others. Landsteiner’s 1901 research organized these differences into blood groups, providing a foundation for understanding transfusion compatibility. His 1930 Nobel Prize recognized the discovery of human blood groups.
Later immunological research
After the First World War, Landsteiner worked in The Hague and then at New York’s Rockefeller Institute for Medical Research. He continued investigating blood groups and the chemistry of antigens, collaborating with Philip Levine, Alexander Wiener and others. He died in New York in 1943.