Grass plants can transport infectious prions

May 16, 2015, University of Texas Health Science Center at Houston
A UTHealth team in Houston led by Claudio Soto, Ph.D., has discovered that grass plants can transport infectious prions. Credit: UTHealth

Grass plants can bind, uptake and transport infectious prions, according to researchers at The University of Texas Health Science Center at Houston (UTHealth). The research was published online in the latest issue of Cell Reports.

Prions are the protein-based infectious agents responsible for a group of diseases called transmissible spongiform encephalopathy, which includes () in cattle, scrapie in sheep, variant Creutzfeldt-Jakob in humans and (CWD) in deer, elk and moose. All are fatal brain diseases with incubation periods that last years.

CWD, first diagnosed in mule deer in Colorado in the late 1960s, has spread across the country into 22 states, according to the Centers for Disease Control and Prevention (CDC), including the counties of El Paso and Hudspeth in Texas. In northeastern Colorado and southeastern Wyoming, the disease is endemic. Soto's team sought to find out why.

"There is no proof of transmission from wild animals and plants to humans," said lead author Claudio Soto, Ph.D., professor of neurology at UTHealth Medical School and director of the UTHealth George and Cynthia W. Mitchell Center for Alzheimer's Disease and Other Brain Related Illnesses. "But it's a possibility that needs to be explored and people need to be aware of it. Prions have a long incubation period."

Soto's team analyzed the retention of infectious prion protein and infectivity in wheat grass roots and leaves incubated with prion-contaminated brain material and discovered that even highly diluted amounts can bind to the roots and leaves. When the wheat grass was consumed by hamsters, the animals were infected with the disease. The team also learned that infectious prion proteins could be detected in plants exposed to urine and feces from prion-infected hamsters and deer.

Researchers also found that plants can uptake prions from contaminated soil and transport them to different parts of the plant, which can act as a carrier of infectivity. This suggests that plants may play an important role in environmental prion contamination and the horizontal transmission of the disease.

To minimize the risk of exposure to CWD, the CDC recommends that people avoid eating meat from deer and elk that look sick or test positive for CWD. Hunters who field-dress deer in an affected area should wear gloves and minimize handling of the brain and spinal cord tissues.

"This research was done in experimental conditions in the lab," Soto said of the next step. "We're moving the research into environmental contamination now."

Explore further: Small loop in human prion protein prevents chronic wasting disease

More information: Cell Reports, www.cell.com/cell-reports/abst … 2211-1247(15)00437-4

Related Stories

Recommended for you

How stem cells self-organize in the developing embryo

January 16, 2019

Embryonic development is a process of profound physical transformation, one that has challenged researchers for centuries. How do genes and molecules control forces and tissue stiffness to orchestrate the emergence of form ...

60 percent of coffee varieties face 'extinction risk'

January 16, 2019

Three in five species of wild coffee are at risk of extinction as a deadly mix of climate change, disease and deforestation puts the future of the world's favourite beverage in jeopardy, new research warned Wednesday.

4 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

TopCat22
5 / 5 (1) May 16, 2015
I am not sure if this article is also alluding the possibility that Prions are responsible for Alzheimer and related human brain diseases.
Mike_Massen
3 / 5 (2) May 16, 2015
From someone who has been an Electronic Engineer for many decades & did a post grad in Food Science recently including microbiology & Prions, I can attest to the value of cross-discipline studies bridging concepts to create a paradigm that neither can individually progress by a suitable class

Eg. In mechanics (of which few units were offered in Electronics) one comes to the view, which can be qualified easily that:-

"Any pump can be turned into an engine & any engine is or can be turned into a pump"

Similarly

"All enzymes are proteins & any protein might well become an enzyme when its dynamics re its interactions are well investigated" sorry Vijay J. @Curtin Uni, I did hassle you on catalysts & enzyme aspects ;-)

In respect of prions as peptide sequences, its not clear type of permutations & combinatorial complexity involved in diseases such as Alzheimers & Parkinson's & influence of Beta Amyloid & Tau, suffice it so say, I am developing a hypothesis & testing ;-)
interstellarsurfer
1 / 5 (1) May 23, 2015
I hope further research is done in this area. With human sewage sludge being used to fertilize vegetable crops, there may exist a vector for prion disease to spread through the population, unnoticed.
Mike_Massen
1 / 5 (1) May 23, 2015
interstellarsurfer offered
I hope further research is done in this area. With human sewage sludge being used to fertilize vegetable crops, there may exist a vector for prion disease to spread through the population, unnoticed
This is an interesting issue & especially so given the tough nature of PrPSc as per CJD & other prion diseases

Anecdotal evidence (Not a specific study but, by way of sequential consequence paths) shows bacteria of many types may be quite adept at consuming prions whether infectious or otherwise in the septic environment of waste sludge & thus the chance of complete sequences finding their way up the food chain past soil & into plants & then animals appears negligible & also confirmed by the nature of fungi/bacteria energy exchanges in soils (long after sewage discharge) further denaturing those peptide sequences capable of having enough information content to turn PrP into PrPSc etc

Interestingly copper as metal or salts binds to Prions

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.