Mice from Yale helped an international research team discover prions in a variety of organs never before thought to host the protein structures.

Prions are believed to cause diseases that produce irreversible neurodegeneration, including Creutzfeldt-Jakob disease, “mad cow” disease and scrapie, according to the Food and Drug Administration Web site.

While scientists have known prions accumulate in nervous and lymph tissues, the study showed that other tissues are susceptible to prion accumulation when chronically inflamed. The study determined the lymphatic system can introduce prions to inflamed regions, and the prions might have the ability to replicate in the new location.

“This study showed that the prions can accumulate in other organs if those organs are inflamed,” said Nancy Ruddle, a professor of epidemiology and public health. “So if there is some type of chronic disease process going on in other organs, the prions can infect those organs too.”

The study was directed by Dr. Adriano Aguzzi at the University Hospital of Zurich, Switzerland, and published Jan. 20 on the Science Web site.

While the work with prions was done in Switzerland, Ruddle provided the overseas researchers with mice that had several types of chronic inflammation.

— Micah Ziegler