Landsteiner

Karl Landsteiner was an Austrian immunologist and pathologist whose work laid the foundations of modern transfusion medicine. Born in 1868 in Vienna, he studied medicine at the University of Vienna and earned his medical degree in 1891, beginning a career focused on pathology and immunology.

In 1901, Landsteiner identified the human blood group system, demonstrating that blood could be divided into distinct types and that transfusion compatibility depended on blood type. This discovery, known as the ABO blood group system, greatly improved the safety of blood transfusions. Landsteiner’s Law, describing the antibodies present in plasma against antigenic determinants not expressed by an individual, became a central concept in immunohematology.

In the 1920s Landsteiner continued his research, eventually emigrating to the United States to work at the Rockefeller Institute for Medical Research. In 1940, he and Alexander S. Wiener described the Rh blood-group system, explaining additional factors that influence transfusion reactions and the risk of hemolytic disease in newborns.

For his discovery of human blood groups, Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930. His work established the scientific basis for blood typing, transfusion safety, and transplantation immunology. Landsteiner died in 1943 in New York City, leaving a lasting legacy in hematology and immunology through the standardized blood typing systems and the broader understanding of immune recognition in transfusion medicine.