Nobel Prize in Physiology or Medicine 2020

Harvey J. Alter, Michael Houghton, and Charles M. Rice

Nobel Media

Today, Monday, the Nobel Assembly at the Karolinska Institute in Stockholm announced this year’s winners of the Nobel Prize in Physiology or Medicine. Harvey J. Alter, Michael Houghton and Charles M. Rice received the award for the discovery of the hepatitis C virus. All three scientists had made decisive contributions to the fight against hepatitis C, an infected blood-borne disease, the jury said. in your statement. Hepatitis C is one of the main global epidemics. The virus causes cirrhosis of the liver and can later lead to liver cancer. People all over the world had to struggle with the consequences of the disease, according to the Nobel Assembly at the press conference.

One of the most common causes of liver cancer and liver transplants.

There are three hepatitis viruses: Hepatitis A is spread through contaminated food or water, for example, and is usually cured within a few weeks. It looks completely different with hepatitis B and C. These are transmitted through blood and other body fluids. They can cause chronic inflammation of the liver that destroys the liver for years and, if left untreated, can lead to liver cancer and cirrhosis. If the liver is so damaged, the only way to treat the disease is with a liver transplant.

Patients suffering from chronic inflammation had often received blood transfusions. Baruch Blumberg identified the hepatitis B virus in the 1960s (and received the Nobel Prize for this discovery in 1976). This virus could explain some, but not all, of chronic inflammation of the liver: the tests carried out reduced part of the inflammation of the liver, but not all.

This is where Harvey Alter and his colleagues come in: they were able to show that there had to be another variant of the virus besides hepatitis A and B. At the time, Alter was working in a large blood bank and investigating the incidence of liver inflammation. in transfused patients. The researchers showed that blood from patients who were not infected with the hepatitis A virus or the hepatitis B virus, but nevertheless suffered from hepatitis, could trigger the disease in monkeys. Further investigation led the researchers to conclude that it was a still unknown virus that caused hepatitis.

This was the starting point of the work for which the three researchers were awarded the Nobel Prize in Physiology or Medicine today.

Michael Houghton, who was working for the Chiron pharmaceutical company at the time, identified the genome sequence of the previously unknown virus. Together with his colleagues, he isolated DNA fragments from the blood of an infected chimpanzee. Many of them came from the chimpanzee himself, but some, the researchers suspected, must also come from the as-yet unknown virus that caused hepatitis. Because antibodies against the virus circulate in the blood of an infected person. So the researchers tested fragments of genetic material that contain the genetic information of viral proteins with the blood of hepatitis patients, and they were successful. In 1989, researchers were able to identify a new RNA virus from the flavivirus family. This was eventually called the hepatitis C virus.

For a long time, blood transfusions were associated with a high risk of infection. We also owe the fact that they are safe today to the work of Alter, Houghton and Rice, the newly crowned Nobel Prize winners.

The question remained: was the new virus the only cause of liver disease? Charles M. Rice (Washington University in St. Louis) discovered a previously uncharacterized genomic sequence of the virus, which he suspected might be important for the replication of the pathogen. In other variants of the virus, on the other hand, he found sites in the genome that could interfere with the reproduction of the virus. Using genetic engineering methods, he constructed a version of the virus that contained the newly characterized sequence, but none of the suspected interfering sequences. When this virus was injected into the liver of a chimpanzee, it multiplied, could be detected in the blood, and symptoms of disease and pathological changes similar to those seen in human patients appeared. It was proof that the hepatitis C virus alone was capable of causing blood transfusion-induced inflammation of the liver that had not been explained before it was discovered.

Thanks to the researchers’ discoveries, there are now highly sensitive blood tests that can be used to screen donated blood for the pathogen. In many regions of the world, this has virtually eradicated chronic liver inflammation transmitted by blood transfusions, writes the Nobel Committee. In addition, the work allowed the development of new drugs that would cure the disease.

Corona also changes the festivities around the Nobel Prize

Harvey J. Alter was born in New York, USA in 1935 and works at the National Institutes of Health in Bethesda, Maryland. Michael Houghton (* 1949) is British and is currently doing research at the University of Alberta in Edmonton, Canada. Charles M. Rice was born in Sacramento, California in 1952 and works at the Rockefeller University in New York. The three researchers each receive one-third of the prize money.

The highest award for scientists this year is endowed with SEK 10 million per category, one million more than last year. Converted, the prize money corresponds to just over a million Swiss francs or almost a million euros. The ceremony to honor the new winners will take place on December 10, the anniversary of the death of founder Alfred Nobel.

However, due to the corona pandemic, this year there will not be a large banquet with around 1,300 guests. The press conference at the Karolinska Institute was poorly attended: In years without a pandemic, the room is packed with journalists from around the world when the winners are announced.

Last year, William Kaelin, Sir Peter Ratcliffe and Gregg Semenza, two Americans and one British, received the Nobel Prize in Medicine or Physiology. (This corresponds exactly to the cliché: all three are male, white, and of retirement age.) His work deals with the question of how cells handle different concentrations of oxygen. Researchers have found a molecular sensor that also plays a role in anemia or cancer.