Stanley B Prusiner
by Peter Ellis

Many people today are wary of eating beef because they fear that they may catch CJD, the human form of "mad-cow disease". News from France and Germany admitting that BSE (the scientific name of the disease) is present in cattle in those countries means that the problem will remain in public view. It is nearly thirty years since Stanley Prusiner became interested in CJD and related illnesses and started the work for which he received the Nobel Prize for Medicine in 1997.

To San Francisco
Stanley Prusiner was born just as the USA entered the Second World War in 1942, and his father was drafted into the Navy. Stanley was the grandson of Russian Jews who emigrated in the last years of the nineteenth century. After the war the family settled in Cincinnati where Stanley's father was an architect. After school, Stanley studied chemistry at Pennsylvania University and he also took courses in philosophy, and Russian history. He decided to train in medicine and became interested in bio-medical research. In 1968 he moved to San Francisco to complete a year working nights in hospital before taking up a research post. The hospital work was difficult but he found time to meet his wife Sandy. Three years later he was back at the University of California in San Francisco studying diseases of the nervous system.

A strange disease
One of the first patients Stanley met was suffering from Creutzfeldt-Jakob Disease (CJD). This distressing illness slowly destroys the memory of the sufferer stopping them from carrying out even simple tasks. The fatal disease was thought to be caused by a slow acting virus. Stanley's interest grew when he found that there were other similar diseases in humans and animal. The Fore people of New Guinea suffered from "kuru", the laughing death, because they ceremonially ate the brains of their elders. Scrapie caused sheep and goats to lose coordination and develop an itch, which they scraped at so losing their wool or hair. All these diseases resulted in parts of the brain becoming spongy the nerve cells replaced by holes.

Infectious diseases are caused by organisms such as bacteria and viruses, which like all living things, contain DNA or RNA that they pass on to their descendents. Stanley found that some researchers in England had failed to find traces of DNA from an infectious agent in the brains of scrapie-affected sheep. This excited Stanley and he embarked on his life's work to find the cause of these diseases.

Prions
By 1982 Stanley and his team had proved, at least to themselves, that the cause of CJD, scrapie and kuru was a strange molecule that they named a prion. Although it contained no DNA or RNA and was in fact simply a protein molecule, it was able to make cells reproduce it. In fact cells usually contained a harmless form of the prion, which could be turned into the deadly kind simply by changing shape if they came into contact with the disease variety. Stanley and his partners had performed thousands of experiments on hamsters infected with scrapie but other scientists didn't believe the results when they were announced. How could a simple protein reproduce and cause the devastating effects that Stanley said prions produced. The media joined the controversy and the attacks of critics became distressing to Stanley, his wife and two young daughters Helen and Leah.

Mad cows
BSE or "mad-cow disease" was first observed in English cattle in 1985 and soon grew to be an epidemic that caused panic amongst farmers, government and shoppers. It is thought that the disease spread because cattle were given feed that contained bits of infected cows. Farmers were encouraged to use this cattle feed as it was cheaper than feed grown from plants. In 1992 alone, 37,000 cattle were found to have the disease. The British Government has tried to end the epidemic by slaughtering all cows over 30 months old and by ensuring that brains and spinal cords which may contain the infection are removed when beef is processed. Despite government reassurances it became clear that there was a small chance that the infection could be passed to humans where it causes a new variant of CJD. Stanley's work showed that BSE and vCJD like scrapie were prion diseases. Stanley had found out a great deal more about how prions were formed, their properties and the chances of infection so with BSE and CJD making headlines across the world it was not surprising that the Nobel committee should award him the 1997 prize. However the prize was unusual because some scientists still argue about Stanley's research believing that while prions may exist, an unknown virus is involved in their formation. Many aspects of the diseases are still uncertain and still there is no cure.

On the Web
You can find out more about Stanley Prusiner and his work at : www.nobel.se/medicine/laureates/1997/press.html
This is the press release from the Nobel committee announcing the award of the prize to Stanley Prusiner

www.nobel.se/medicine/laureates/1997/prusiner-autobio.html
This is Stanley Prusiner's autobiography that accompanies the Nobel site.

www.nmia.com/~mdibble/prion.html
A more detailed description of the work on prion diseases by Stanley Prusiner

There is still controversy about Prusiner's work and Gary Taubes gives the opposing view at:
www.slate.com/HeyWait/97-10-10/HeyWait.asp

To find out more about BSE then go to
www.mad-cow.org
This site gives access to a very large number of other sites on all aspects of BSE and related topics.
(Good places to start are the news item for October 23rd 2000 about the Phillips Inquiry. A full story of BSE is given at the site listed under "Mad Scientists", Lacey:How Now Mad Cow.)

An account of CJD and prions is given by Melissa Ehlert at: www2.Kenyon.edu/depts/biology/slonc/bio38/ehlert/prion.htm

More on this site!
Go to questions on Prusiner's life and discoveries.
Go to Teacher's Notes for more and answers to the Web activity.
Go to the Scientist of the Month Archive