Viruses that 'come back to life' could lead to vaccines that last longer, are cheaper and easier to transport, and most importantly—save lives.
VIRUSES GET A BAD RAP. Yes, they give us colds and the flu, they infect our bodies and in many parts of the world, they can kill. They spread like crazy, which is how malicious computer bugs got their name. But viruses also play positive roles in nature. They kill bacteria, for one, and they form the basis of many life-saving vaccines. So while it's sometimes good to kill viruses, at other times it's better to save them.
Biology professor Ken Stedman (left) and graduate student James Laidler have found a way to save them.
They found that coating viruses in a silicate shell can keep them in a state of suspended animation. The shell dissolves and the virus becomes active again when exposed to water. Stedman nicknamed the process "zombification" because the "undead" viruses come back to life once the coating has been removed.
The discovery is important because the technique could extend the shelf life of vaccines and allow for storage at room temperatures. Vaccines preserved in this way could be given orally or injected into a patient, and the glassy coating would harmlessly melt away.
This could alleviate a longstanding problem with vaccines: They are often extremely fragile and will spoil quickly if they're not stored at a cold temperature. Nearly half of vaccines produced every year spoil due to inadequate refrigeration during transport.
"It's really hard to put a fridge on the back of a donkey," says Stedman. "This process has the potential to stabilize vaccines so that they can get to more places and more people more often. Six million people per year—mostly children—die from diseases that could be helped with vaccination."
The process could save the pharmaceutical companies that make vaccines about $2.3 billion per year by cutting product losses, Stedman adds. It would also reduce the cost of shipping and encourage the development of new markets.
STEDMAN AND LAIDLER discovered zombie viruses while taking samples from bubbling hot springs in the American West. They found that silica from the hot springs protected the viruses from drying out and allowed them to stay viable outside their natural environment.
Back in the lab, they were able to replicate the coating process. The work involves placing a liquid solution containing viruses into a membrane bag, and putting the bag into a prepared solution of sodium metasilicate, also known as water glass. The membrane's microscopic pores are large enough to let the water glass pass through, but small enough to keep the viruses contained. After a while, the scientists take out the bag and put it in a fresh solution to do another coating. They do this again and again to slowly build the shell.
Taking this initial discovery and turning it into something for widespread use will require five to 10 more years of experiments. Fortunately computational equipment funded by Duane and Barbara McDougall '75 helps process the massive amount of data required in Stedman's research. The equipment translates complex substances collected by Stedman and other Portland State scientists into mathematical data that can be analyzed and modeled.
While Stedman and Laidler continue their experiments, PSU students in a senior year capstone course are looking into the business possibilities of zombie viruses.
"This has amazing and profound potential," says professor Ted Khoury, who teaches the class. Working with PSU's Center for Innovation and Entrepreneurship, Khoury and his students are examining nonprofit funding ideas, patenting and strategies for the best way to bring the idea to market.
Another class taught by engineering professor Antonie Jetter, is also looking at the zombie viruses' market potential, but from a little different angle.
"My students are engineering graduates, and they're strong in technology analysis," she says. Her students are talking to potential end users of the technology, including clinicians who know how to store vaccines. They're also looking at how the vaccine market is structured, and may point out business possibilities that Stedman and others hadn't thought of.
"It could inform Ken on what to do for his next round of experiments," says Jetter.
NOT ONLY could the discovery result in safe transit of more vaccines to the developing world, but it could also give clues to the origins of life on Earth and the possibility of life on other planets, including Mars. NASA provided funding for Stedman's research because of this extraterrestrial possibility.
Water, and perhaps oceans, once coated the surface of Mars, according to data from several NASA missions. "Whether microbes were in the supposed Martian water is still up for debate," states an article about Stedman's research in the November 2013 issue of Astrobiology Magazine. If they were, then they might be fossilized on the Martian landscape. But Stedman says scientists don't even know how to look for viruses in the geologic record of Earth, let alone Mars.
"I'm convinced there are viruses in the rock record, but we don't have the technology to detect them," Stedman says in the article. "We really need to develop the technology here before we can even think about going to look there. We're trying to do just that."
Here on Earth, it's clear that once viruses are covered in silica, they are extremely resistant to drying out. They might also survive deep freezes and other harsh conditions. Stedman says that when viruses are encapsulated this way, they can be disbursed for many miles by geysers, fumaroles, or even volcanic explosions.
Knowing that, is it possible that viruses could be transported by meteorite from one planet to another? As enticing as that idea is, Stedman doesn't think so—although questions like that are always on the minds of people who study the stars.
For now, his big goal is to be able to transport preserved vaccines to the developing world—by donkey if need be.
John Kirkland is a staff member in the PSU Office of University Communication.
Caption: Ken Stedman, biology faculty, experiments with viruses such as the T4 bacteriophage depicted in the illustration (copyright Russell Kightley). Coating the virus in a silicate shell keeps it in a state of suspended animation until it is revived with water, which dissolves the shell. He nicknamed the process "zombification."