The disease-associated form of prion protein (PrPres) has been found in lymphoreticular tissues in patients with variant Creutzfeldt-Jakob disease (vCJD).
In this study, investigators from France assessed the transmissibility of bovine spongiform encephalopathy (BSE) both intravenously and orally.
The team infected cynomolgus macaques with brain homogenates from first-passage animals with BSE.
|The disease-associated form of prion protein occurred in the gut from the duodenum to the rectum.|
Tissue samples were analyzed by sandwich ELISA and immunohistochemistry to give a quantitative and qualitative assessment of their PrPres content.
The investigators found that incubation periods after intravenous transmission of BSE were much shorter than after oral infection.
They established that PrPres was present in lymphoreticular tissues such as spleen and tonsils, as well as in the gut from the duodenum to the rectum.
The team found that PrPres occurred in Peyer's patches, in the enteric nervous system and in the nerve fibers of the intestinal mucosa.
The investigators determined that the amount of PrPres ranged between 0.02% and > 10% of that recorded in the brain.
Dr Herzog's team concluded, "Our findings suggest that the possible risk of vCJD linked to endoscopic procedures might be currently underestimated".
"Human iatrogenic vCJD cases infected intravenously raise the same public-health concerns as primary cases and need the same precautionary measures with respect to blood and tissue donations and surgical procedures".