Stony Brook team aids effort to make polio vaccine
No disease in the first half of the 20th century struck fear the way polio did.
Highly contagious, paralytic, crippling and, in some instances, deadly, it was a seasonal menace that required a titanic scientific effort to identify the tiny virus and contain its spread through vaccines.
Now, scientists at Stony Brook University stand to play a role in what could be polio's last years on the planet.
Dr. Eckard Wimmer and a team of Stony Brook researchers have genetically engineered a strain of the pathogen that lacks the extreme virulence factor of the so-called wild type virus -- the one that arose many millennia ago in nature.
Wimmer's lab is providing the seed viral material for a candidate vaccine to be produced by Janssen Pharmaceuticals Inc., a division of Johnson & Johnson. The World Health Organization asked Wimmer and other experts to aid in the last big push to snuff out polio -- formally known as poliomyelitis -- forever.
"The World Health Organization asked us scientists who have made viruses for various reasons to work on this," Wimmer said.
"They said it's got to grow very well like the wild type and it should have a coat protein like the wild type," he said, "but it should not cause disease if it gets out of the production facility."
Seeking total eradication
Essentially, the WHO was asking scientists to design a nonvirulent poliovirus that possessed all of the other features of the real thing.
It was a tall order but could set the final stage for worldwide eradication of a formidable foe.
Only two other viral scourges have been eradicated worldwide: smallpox, a deadly disease, was declared eliminated in 1977.
In 2011, rinderpest, a horrific viral disease of even-toed ungulates -- cattle, buffalo, giraffes and deer, was officially announced eradicated.
Wimmer, who holds the title of distinguished professor, has worked on a variety of poliovirus studies for nearly half a century.
In 2002 he became the first scientist in the world to create a poliovirus from scratch, generating viral particles that were capable of successfully infecting living cells in the lab. Those viruses were constructed from genetic-sequencing information pulled from the scientific literature and followed like a recipe.
The new strain that will provide the seed stock for the Janssen vaccines is a highly engineered microbe with special features, said Dr. Jeronimo Cello, Wimmer's Stony Brook collaborator. "The wild type poliovirus causes disease by destroying the body's motor neurons," Cello said of nerve cells that serve the muscles. "We engineered the virus so that it has lost the capacity to cause damage in the central nervous system.
Causing immune response
Even though the Stony Brook virus is devoid of its virulence factor, Cello said, it still possesses the same surface proteins, which would allow a vaccine made from the particles to stimulate a vigorous immune response.
The WHO put out the call for a new type of vaccine because it plans to retire those based on the Sabin oral vaccine, which has live viral particles. The Sabin, along with the Salk vaccine, which is made of three inactivated wild type viruses, helped eradicate polio in most of the world.
The WHO estimates polio cases have dramatically plummeted -- by about 99 percent -- since the 1988 launch of the Global Polio Eradication Initiative.
The virus is largely spread from feces via contaminated food or water. Direct contact with an infected person also can cause polio.
Through the ongoing eradication initiative, only 222 confirmed cases were caused by the wild type virus in 2012, according to the WHO.
Some experts estimate polio -- with the aid of new vaccines -- could be eradicated in as few as six years.
Yet an independent monitoring board of the global eradication initiative warned in a recent report of a significant risk that polio could make a stunning resurgence this year.
Two vaccinators working as part of the global campaign were killed by political factions last month in Pakistan, according to news reports. Five were killed there in December. News reports last week indicated 10 vaccinators were killed in Nigeria by religious extremists who believe the polio vaccine causes sterility in girls.
"We're trying to do all we can. It's a tricky little virus," Wimmer said of the wild type strain.
"I have been working on it for 44 years. I was working on it before I came to Stony Brook and I would really like to see the end of this disease in the entire world."