Study Suggests Blood-Cell Role in Cow Disease

The rogue proteins that cause mad cow disease and its human equivalent need help from particular blood cells to reach the brain from elsewhere in the body, an animal study suggests.

It’s not clear whether B cells actually carry prion proteins, researcher Dr. Adriano Aguzzi said.

But if they do, blood banks could guard against transmitting the rare prion disorder called Creutzfeld-Jakob disease by removing B cells and other white blood cells from blood for transfusion, he said.

There’s no evidence that CJD has ever been transmitted by transfusion. Nonetheless, blood and blood products collected from people who are later diagnosed with CJD are now routinely discarded.

Aguzzi, a professor of neuropathology at the University of Zurich in Switzerland, and Swiss colleagues report their study in the Dec. 18 issue of the journal Nature.

They inoculated various strains of mice with prions, which cause the brain-destroying disease scrapie in those animals. Mice that lacked mature B cells were protected, indicating that the B cells play some crucial role in getting prions into the brain.

Scientists are now studying whether B cells carry prions, Aguzzi said.