Paul Ehrlich

Science / Scientists' Datebook: March 14

 

Brief biography of Paul Ehrlich, German scientist in the fields of immunology, chemotherapy and hematology. He introduced the word chemotherapy, the chemical that kills cancerous cells.Famous for discovery of Salvarsan, NeoSalvarsan, and Chemotherapy.

 

 

Nobel laureate Paul Ehrlich was a German bacteriologist who worked on immunization. His search for a “magic bullet” against disease and discovery of salvarsan, a chemical effective against syphilis microbes, introduced the modern era of chemotherapy, a term Ehrlich coined.

Profile in a Nutshell  

Paul Ehrlich was born in Strehlen, Upper Silesia, Germany, on March 14 1854. He received his doctorate of medicine in 1878. Four years later, he published his methods for staining the bacteria that Robert Koch had identified as being the cause of tubercolosis.

In 1890, he was 36 years old, Koch invited him to move to the newly established Insititute for Infectious Diseases in Berlin. There, he eventually became the first director of the Institute for the Control of Therapeutic Sera.

He shared the 1908 Nobel Prize for Physiology/Medicine with Ilya Ilyich Mechnikov.  Ehrlich died of a second stroke while on holiday in Bad Homburg, on August 20, 1915.

Robert Koch Inspires Paul Ehrlich

In his late 20s, Ehrlich attended a lecture given by microbiologist Robert Koch. Koch was talking about the bacillus that causes tuberculosis, saying it was difficult to recognize. Inspired by Koch, Ehrlich set out to solve the problem. What was required was a stain that bound to these strange bacteria. He tried numerous different dyes but was unsuccessful at this point.

Diphtheria, Toxins and Anti-Toxins

In 1890, upon Koch’s invitation he joined the Institute for Infectious Diseases in Berlin. Working with Emil Behring, he turned his attention to diphtheria. His tests showed that the disease was not caused by the diphtheria bacteria, but by chemicals released from the bacteria. These toxins destroyed blood cells and consequently killed the infected animal.

Further observation showed that not all animals died. Some were immune, and Behring realized that they were producing a chemical that could neutralize the bacterial toxin – they were in fact, making an anti-toxin. More important, Ehrlich found ways of isolating the anti-toxin and using it to treat people affected by diphtheria.

Thinking about the way toxins work, Ehrlich came up with the idea that part of the toxin molecule locks on to cell walls in the host, while another part of the molecule causes the damage. He suggested that if the cell survived the attack, it would produce more receptors (or antibodies) and let them fall off into the blood stream. The toxin would then bind to these free-floating antibodies, and consequently not be able to bind to any cell.  

Dyes and Magic Bullets

In 1896, Ehrlich focused in his search for the “magic bullet.” His theory was that if the body could produce antibodies that neutralized toxins there must be a way of making chemicals artificially that would have a similar effect.

Ehrlich and his Japanese assistant, Kiyoshi Shiga, found that one particular red dye was capable of destroying these parasites in the laboratory, and this proved that the concept of finding killer chemicals was viable.

Salvarsan as Syphilis Cure

His next target was the bug that causes syphilis, a spirochete. At the time he was working to develop a series of compounds that incorporated arsenic, and he started testing them one by one. The first 605 didn’t have any effect, but compound 606 did.  After performing numerous experiments to make sure that the chemical really did kill the syphilis bug but didn’t harm humans, he announced the new wonder drug, calling it “Salvarsan.” The drug worked, but was difficult to manufacture, so he started looking for another.

Compound 914 proved a winner. It was not as potent but was much easier to make, he named it “Neosalvarsan” and launched it on the market. His search for “magic bullets” had led to the era of  chemotherapy – the chemical designed to cure cancerous cells.   

Contribution of Dr. Paul Ehrlich

In the late 1800s, diseases such as cholera, typhoid, tuberculosis, and diphtheria were prevalent. Dr. Paul Ehrlich sought ways how to combat these diseases. He was convinced that he could find “magic bullet” chemicals that would fill the bacteria without harming the person infected.

After finding the chemicals that could treat syphilis and sleeping sickness, Ehrlich successfully worked out the concept of fighting malignant diseases with chemicals he coined as “chemotherapy,” in particular, designed to cure the cells of cancer.      

 

Photo Credit:

Paul Ehrlich.  Wikipedia Commons / Public Domain

 

Resources:

Farndon, John, et al. The Great Scientists. Capella / Arcturus, 2005

Moore, Pete. E=MC²: The Great Ideas That Shaped Our World. London: Quintet Publishing, 2002

Paul Ehrlich. en.wikipedia.org. 

(c) March 2010. Updated March 10, 2024. Tel Asiado. Inspired Pen Web. All rights reserved.