November 25, 2008
4 min read

Karl Landsteiner discovered the four blood groups

Landsteiner’s studies laid the groundwork for important future research in immunology.

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Amidst the grim backdrop of a war-torn Vienna, Karl Landsteiner’s scientific explorations in the areas of hematology, immunology and bacteriology cemented his place in history as one of the most influential figures in modern medicine. Though the environment was not ideal for making significant strides in research, Landsteiner resolutely pursued his theories, eventually relocating to make his investigations possible.

His international sojourns included stints at the Pasteur Institute in Paris; RK Ziekenhuis, Catholic Hospital in The Hague, Holland; and the Rockefeller Institute in New York, where he spent much of his career. All the while, Landsteiner’s innovative conclusions and “chemist’s approach” to immunology earned him worldwide recognition as the premier expert on the mechanisms of immunity, bestowing unwanted fame on the very private man.

Austrian stamp issued to commemorate the 100th year from Landsteiner’s birth
Austrian stamp issued to commemorate the 100th year from Landsteiner’s birth.

Source: S Shulman

Yet, no matter how much he disliked publicity, Landsteiner could not avoid the renown that accompanied his winning the Nobel Prize for discovering the four blood groups. However, Landsteiner’s forays into other immunological and hematological studies greatly contributed to his role as a major, groundbreaking figure in the medical world as well.

A young chemist

Landsteiner was born on June 14, 1868, in Vienna, the sole child of doctor-of-law and famous Viennese journalist, Leopold Landsteiner, and his wife Fanny Hess Landsteiner. When Landsteiner was 6 years old, his father died from a massive heart attack. Landsteiner was then raised by a family friend but maintained a close bond with his mother.

At the age of 17, Landsteiner entered medical school at the University of Vienna. There, he demonstrated a significant interest in chemistry. After taking a year off from school to complete his military service, Landsteiner commenced training at the Second Clinic for Internal Medicine in 1891. Eventually, after graduation from medical school, his passion for chemistry led him to pursue advanced studies in the field of organic chemistry under his mentor Ernst Ludwig.

For the next 10 years, Landsteiner spent time in some of the most renowned laboratories throughout Europe. He worked with the Nobel Prize-winning Emil Fischer, a protein chemist, in Wurzburg; Eugen von Bamberger in Munich; and Arthur Hantzsch and Roland Scholl in Zurich. During this time, Landsteiner published many journal articles with these distinguished scientists and acquired significant knowledge about chemistry that fostered his interest in immunology.

Important discoveries

After serving under Max von Gruber at the University of Vienna’s Institute of Hygiene, Landsteiner transferred to the department of pathological anatomy in 1897 where immunology and serology occupied his independent studies. It was here that Landsteiner made his most famous discovery.

In 1900, Landsteiner published a paper that made the first mention of the isoagglutination of human blood, proposing that the occurrence was linked with the uniqueness of an individual’s blood as opposed to having a pathological cause.

One year later, Landsteiner cross tested sera and red cells from scientists working in his lab, including his own. His findings revealed that blood from certain scientists caused the blood of others to clump, suggesting the existence of at least two antibody classes. Landsteiner promptly dubbed them anti-A and anti-B. Eventually, his valuable conclusions led to the identification of the four blood groups: A, B, O, and AB. Consequently, Landsteiner’s discovery laid the groundwork for the first successful blood transfusions in 1907.

Landsteiner also suggested other uses for his findings. In 1902, he recommended that blood grouping could be used in paternity cases as well as proposing its forensic application in the solving of crimes where blood stains were left on the scene.

During this time, Landsteiner’s intense work schedule afforded him little free time. Even so, in 1916, he married Helene Wlasto with whom he had a son, Ernst Karl, who would later become a doctor as well.

Beyond blood types

In addition to his celebrated revelations regarding blood typing, Landsteiner also labored to devise a polio vaccine. After performing an autopsy on a young boy with polio, he conducted numerous experiments that involved injecting the disease into various animals.

His studies brought him to the Pasteur Institute where he and other scientists were able to connect poliomyelitis to a viral cause. Though a vaccine would not be made until years later, Landsteiner’s research provided the foundation for its creation.

Landsteiner’s work with syphilis during this period also was noteworthy. He not only pioneered the usage of dark-field microscopy to detect the spirochetes of syphilis, but also worked diligently by examining the disease’s human-to-animal transmission, hoping to find antibodies related to immunity.

Additionally, from 1919 to 1922, Landsteiner’s background in chemistry inspired him to investigate haptens to establish the specificity of serological reactions. His examination of these antigen-antibody reactions ultimately led him to explore the chemical and immunological basis of skin sensitization and allergy.

Landsteiner relocated permanently in 1922, finally accepting a position at the Rockefeller Institute. Though Landsteiner officially retired in 1939, he went on to collaborate with Alexander Wiener. The two scientists discovered the Rhesus (Rh) factor in 1940, supplying the “pathophysiological basis for erythroblastosis” and illustrating the relationship between a mother and a fetus’s blood types and antibodies.

Landsteiner suffered a coronary obstruction and died on June 26, 1943. His life’s work was collected and published as The Specificity of Serological Reactions. – by Melissa Foster

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