Karl Landsteiner
Austrian-American immunologist who classified blood groups and discovered the Rhesus factor.
Karl Landsteiner, an Austrian-American biologist, physician, and immunologist, is best known for his groundbreaking work on blood. In 1901, he identified the main blood groups by detecting agglutinins in the blood, creating the foundation for the modern blood group classification system. Later, in 1937, he worked with Alexander S. Wiener to discover the Rhesus factor, a breakthrough that made blood transfusions much safer. Alongside Constantin Levaditi and Erwin Popper, Landsteiner also isolated the polio virus in 1909. For his contributions, he received the Nobel Prize in Physiology or Medicine in 1930 and is often called the father of transfusion medicine.
Born into a Jewish family in Vienna, Landsteiner lost his father, a prominent journalist, at age six and grew close to his mother. After finishing secondary school, he studied medicine at the University of Vienna, earning his doctorate in 1891. Even as a student, he published an essay on how diet affects blood composition. He then spent several years studying chemistry under notable scientists in Würzburg, Munich, and Zurich, producing a number of papers, some co-authored with his professors.
Returning to Vienna, Landsteiner worked as an assistant at the Hygienic Institute, focusing on immunity and antibodies. From 1897 to 1908, he was at the pathological-anatomical institute, where he published 75 papers on serology, bacteriology, virology, and pathology, and performed around 3,600 autopsies. He qualified as a lecturer in 1903 and later served as a prosector at the Wilhelminenspital. During this period, he and Erwin Popper proved that polio was infectious and isolated the virus, a discovery that later earned him a posthumous place in the Polio Hall of Fame.
In 1900, Landsteiner observed that blood from different people would clump together, and by 1901 he traced this to contact between blood and blood serum. This led him to identify three blood groups—A, B, and O (which he initially called C). He showed that transfusions between people of the same group were safe, while mixing different groups caused destruction of blood cells. The first successful transfusion based on his findings was performed in 1907. Today, his work explains why people with type AB blood can receive red cells from any group (universal recipients) and those with type O-negative can donate to anyone (universal donors), since O-negative lacks A and B antigens.
After World War I, Austria’s poor economy forced Landsteiner to move to the Netherlands, where he worked as a prosector at a hospital in The Hague and took a job at a small factory making tuberculin. Finding conditions still difficult, he accepted an invitation from the Rockefeller Institute in New York, arriving in 1923. There, he studied immunity and allergy, and in 1927 he discovered additional blood groups—M, N, and P—which soon found use in paternity cases. Landsteiner also received the Aronson Prize in 1926 and, after his death, the Lasker Award in 1946.
- born
- 14 June 1868
- died
- 26 June 1943
- field
- Biology, medicine, immunology
- nationality
- Austrian-American
- known_for
- Classification of blood groups, discovery of the Rhesus factor, discovery of the
Verified Timeline
Lore & Background
Karl Landsteiner was born into a Jewish family on 14 June 1868. His father Leopold, a renowned Viennese journalist and editor-in-chief of Die Presse, died when Karl was six. He became very close to his mother Fanny. After graduating with the Matura exam from a Vienna secondary school, he studied medicine at the University of Vienna, writing his doctoral thesis in 1891. From 1891 to 1893, he studied chemistry in Würzburg under Hermann Emil Fischer, in München under Eugen Bamberger, and in Zürich under Arthur Rudolf Hantzsch. Returning to Vienna, he became an assistant to Max von Gruber at the Hygienic Institute. From November 1897 to 1908 he was an assistant at the pathological-anatomical institute under Anton Weichselbaum, publishing 75 papers and performing some 3,600 autopsies. In 1909, with Constantin Levaditi and Erwin Popper, he discovered the polio virus. From 1908 to 1920 he was prosector at the Wilhelminenspital in Vienna, and in 1911 he was sworn in as an associate professor of pathological anatomy. After World War I, he moved to the Netherlands, working as a prosector at St. Joannes de Deo hospital in The Hague. In 1923 he emigrated with his family to New York to work for the Rockefeller Institute. He converted from Judaism to Christianity in 1890 and was baptised into the Catholic Church. In 1916, he married Leopoldine Helene Wlasto, a Greek Orthodox woman who converted to his Catholic faith.
Reader's Guide
Landsteiner's significance lies in his foundational contributions to transfusion medicine. In 1900 he found that blood of two people under contact agglutinates, and in 1901 he identified the three blood groups A, B and O (which he labelled C). He also found that blood transfusion between persons with the same blood group did not lead to the destruction of blood cells, whereas this occurred between persons of different blood groups. Based on his findings, the first successful blood transfusion was performed by Reuben Ottenberg at Mount Sinai Hospital in New York in 1907. In 1937, with Alexander S. Wiener, he identified the Rhesus factor, enabling physicians to transfuse blood without endangering the patient's life. In 1909, with Constantin Levaditi and Erwin Popper, he discovered the polio virus, which proved to be the basis for the fight against polio. For his work on blood groups, he received the Nobel Prize in Physiology or Medicine in 1930. He was posthumously awarded the Lasker Award in 1946, and has been described as the father of transfusion medicine. Since 2005, World Blood Donor Day is celebrated on Landsteiner's birthday anniversary.
Did You Know?
- Landsteiner performed some 3,600 autopsies in ten years while at the pathological-anatomical institute of the University of Vienna.
- He discovered the polio virus in 1909 with Constantin Levaditi and Erwin Popper.
- He was posthumously inducted into the Polio Hall of Fame at Warm Springs, Georgia, in January 1958.
- Landsteiner converted from Judaism to Christianity in 1890 and was baptised into the Catholic Church.
- World Blood Donor Day is celebrated on Landsteiner's birthday anniversary since 2005.
Frequently Asked Questions
Who is Karl Landsteiner?
Karl Landsteiner was an Austrian-American immunologist and physician born in 1868 who became one of the most influential figures in modern medicine. He is celebrated for mapping the major human blood groups and for his foundational work on viruses.
What discovery made Karl Landsteiner famous?
In 1901, Landsteiner identified the distinct blood group types present in human blood, a breakthrough that made safe transfusions possible for the first time. This work earned him the Nobel Prize in Physiology or Medicine in 1930.
What is the Rhesus factor and how did Landsteiner discover it?
The Rhesus factor is a protein marker on red blood cells that determines transfusion compatibility, and Landsteiner identified it in 1937 alongside Alexander S. Wiener. This finding explained why certain transfusions failed and reshaped both prenatal and transfusion medicine.
Did Karl Landsteiner discover the polio virus?
Yes, in 1909 Landsteiner worked with Constantin Levaditi and Erwin Popper to isolate the poliovirus for the first time. This was a landmark moment in virology, though a practical vaccine would not arrive until decades later.
How did Karl Landsteiner's life end?
Landsteiner passed away on 26 June 1943, just over a month after his 75th birthday, while living in the United States. He had emigrated from Austria in the 1930s and spent his final years as a researcher at Rockefeller University in New York.
More in Pioneers Of Medicine 1-24
Spotted an error? Know more?
This is a living reference — every entry is fact-audited, and reader corrections feed straight into our audit queue. Suggest an edit · See this site's audit record