Prions stay out

New research finds brain cell receptors that let the killer prions in

Published: Saturday 31 January 1998

recently conducted research in Germany and Brazil has revealed how prions -- renegade proteins responsible for transmissible spongiform encephalopathies (certain brain disorders) -- enter brain cells through receptors on their surfaces, eventually destroying them. Prions cause the dreaded mad-cow and Creutzfeltd-Jakob diseases which kill brain cells of the affected patient. If the discoveries hold up, treating and even halting prion-related disorders might be possible by blocking these receptors.

Patrick Bosque, neurologist at the University of San Francisco's School of Medicine, was reported to have said that though the outcome of the research was interesting, the techniques employed to find the receptors had many problems that could often lead to false results. But he agreed that the research is certainly worthwhile.

A protein fragment from a certain prion, which is particularly toxic to brain cells, was artificially copied and used to find a receptor site on normal brain cells. Brain cells use special proteins called cell adhesion molecules, which bind cells in proper alignment for sending signals through the brain, Bosque said. These receptors may play a role in this organising process.

The German team, led by Ernst Winnacker, director of the Gene Centre at University of Munich, used a technique known as "yeast two hybrid screen" to identify the proteins that interact with prions. They found one, identified as the laminin receptor precursor, that is also present on the brain cell membranes. In animal studies, the laminin receptor precursor increases along with infectious prion proteins. However, the researchers stressed that it was impossible to determine whether either of these molecules was the critical receptor for prion infection.

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.