Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study shows prions stick around in certain soils

11.09.2003


Dirt may help scientists answer a question that has baffled them for decades: How does chronic wasting disease (CWD) in deer and elk spread from animal to animal?

By turning to the land, University of Wisconsin-Madison researchers show that prions - infectious proteins considered to be at the root of the disease - literally stick to some soil types, suggesting that the landscape may serve as an environmental reservoir for the disease.

The findings will be discussed during a poster presentation on Wednesday, Sept. 10, in New York City at the 226th national meeting of the American Chemical Society.



Extraordinarily resistant to a range of environmental conditions and decontamination measures, prions are abnormally folded proteins that can make an animal’s brain as holey as a sponge. They’ve been implicated as the cause of diseases such as mad cow and scrapie in sheep.

Once infected, deer and elk, for example, experience a number of neurological and behavioral problems - staggering, shaking and excessive salivation, thirst and urination - until they waste away, many times dying in fields or woods. The disease is always fatal, and, to date, there is no cure.

Even though chronic wasting disease was first detected in free-ranging deer and elk in Colorado and Wyoming during the mid-1980s, it received a charge in scientific and public interest in February 2002, when the first evidence of the disease in Wisconsin appeared.

"The route by which CWD is transmitted from animal to animal is not understood," says Joel Pedersen, an environmental chemist and lead investigator on the soil study. "Strong circumstantial evidence suggests an environmental reservoir exists." Reports show, for instance, that healthy elk placed in pens where animals infected with CWD had once lived developed the fatal disease.

With funding from a recently awarded five-year, $2.4 million grant from the Department of Defense’s National Prion Research Program, Pedersen and his colleagues are examining the ability of the infectious agent to associate with or be absorbed by certain soil particles.

"Soil is a candidate [as an environmental reservoir] because grazing animals ingest it both inadvertently, as part of feeding, and on purpose, as part of certain deer behaviors," explains Pedersen.

To begin to understand how the disease stays in the environment, Pedersen and his colleagues turned to sand and clay - common components found in soils. Because of differences in surface area and mineral composition, Pedersen says sand and clay represent different ends of the spectrum in the ability to absorb proteins.

From the study’s results, the capacity of sand and clay to take up abnormally folded proteins, says the lead researcher, "differs dramatically."

Pedersen and his colleagues determined this by taking samples of sand and clay and adding infectious prions taken from hamsters, as well as a water-based solution representing one found naturally in soils. After removing the water and doing further analysis, they noticed that many of the prions in the sand mixture remained in the water solution, whereas those in the clay mixture stuck to the particles’ surface.

"Almost all the prions in the clay mixture associated with the clay, not the water," says Pedersen, adding that this finding suggests that the movement of prions through the landscape depends on the soil environment.

Understanding how the infectious agent moves - or, in the case of soils with high clay concentrations, stays put - could lead to new information on disease transmission or techniques for managing CWD. For instance, Pedersen says, "If we decide to bury infected carcasses, a clay liner underneath the landfill may be a good idea."

But while clay soils may work to contain infection, they may also help spread it. Whereas prions in sandy soils either may wash away or travel deeper into the ground, says Pedersen, those in clay soils may remain near the surface. "Because the material may be more available for ingestion by animals," he explains, "the rate of infection may be greater."

Analyzing the absorption capacity of sand and clay is just the first step, says Pedersen. In addition to quantifying the ability of prions to bind to these two soil components, they’ll consider other soil materials, additional soil minerals and organic matter. Also under way are studies to determine the degree to which prions in different soil types remain infectious.

"What we’ll be getting at is if prions are more likely to persist in some environments," says Pedersen, adding that results from all these studies will help natural resource managers and other experts perform risk assessments for the spread of CWD and similar diseases across the landscape. "Understanding the role of soil in the spread of CWD is critical in designing and implementing effective disease strategies."


###
- Emily Carlson 608-262-9772, emilycarlson@wisc.edu

Joel Pedersen | EurekAlert!
Further information:
http://www.wisc.edu/

More articles from Life Sciences:

nachricht Bolstering fat cells offers potential new leukemia treatment
17.10.2017 | McMaster University

nachricht Ocean atmosphere rife with microbes
17.10.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Plant escape from waterlogging

17.10.2017 | Life Sciences

Study suggests oysters offer hot spot for reducing nutrient pollution

17.10.2017 | Life Sciences

Breaking: the first light from two neutron stars merging

17.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>