Prions are a modified form of normal proteins, the prion proteins, which become infectious and accumulate in the nervous system causing fatal neurodegenerative disease. Variant CJD results from eating contaminated beef products from cattle infected with mad cow disease. To date, 155 cases of confirmed and probable vCJD in the world have been reported, and it is unclear how many others are carrying the infection.
According to the study's senior author Neena Singh, M.D., Ph.D., associate professor of pathology, little is known about the mechanism by which prions cross the human intestinal barrier, which can be a particularly difficult obstacle to cross.
"The mad cow epidemic is far from over, and the continuous spread of a similar prion disease in the deer and elk population in the U.S. raises serious public health concerns," said Singh. "It is therefore essential to understand how this disease is transmitted from one species to another, especially in the case of humans where the infectious prions survive through stages of cooking and digestion."
Using brain tissues infected with the spontaneously occurring version of CJD which is also caused by prions, the researchers simulated the human digestive process by subjecting the tissue to sequential treatment with digestive fluids as found in the
Contact: George Stamatis
Case Western Reserve University