How deadly brain disease spreads from gut

Offering hope for early detection of prion disease, a difficult to detect deadly brain condition in humans and farm animals, researchers have found how the proteins that cause the disorder spread from our gut.

Until now, it was not known the proteins - called prions - spread from the gut to the brain after consuming contaminated meat.

"We need a greater understanding of what factors enhance our susceptibility to prion diseases so that we can put in place safeguards to prevent these conditions from spreading in people and farmed animals," said lead researcher Neil Mabbott, professor at University of Edinburgh in Scotland.

It is important to spot the detection early as many people could be carrying infectious prions without showing any symptoms of disease.

For the study, the researchers studied the course of prion infection in mice.

They found that prions must first build up in specialised structures in the lining of the small intestine before they are able to spread throughout the body to the brain.

The structures - called Peyer's patches - are part of the body's immune system and form the first line of defence against contaminated food.

Prions hijack Peyer's patches to cause infection, the findings showed.

Prions did not build up in similar patches in the large intestine until a later stage of infection, the team found. At this stage, prions were also detected in the spleen and lymph nodes.

When prions get into the brain, they destroy nerve cells. This can lead to major neurological symptoms including memory impairment, personality changes, and difficulties with movement.

However, in people, the disease remains very rare - 229 people have died from it since it was first identified almost 20 years ago, the study noted.

The findings appeared in the Journal of Virology.