A team of researchers from the University of Navarra, formed by biologists Zuberoa Marcos, Laura Guembe, María Pilar Sesma and María Elena Bodegas, has detected the presence of the prion protein in the digestive tract of three animal species: the native Pyrenean cow, primate and rat. This study is the first to describe the exact location of the "healthy" form of the prion (PrPc), a protein necessary for the development of prion diseases in these three species.

data The results obtained by the Navarre researchers provide new information on the propagation of the prion (and thus the jump from one species to another) and the development of encephalopathies through the ingestion of contaminated food. It is important to note that these findings could be extrapolated to other species, including humans, since the three species studied have a practically identical patron saint .

As is well known, most of the cases of bovine spongiform encephalopathy (BSE) detected in the Autonomous Community of Navarra in the period 2001-2004 correspond to cows of the Pyrenean breed. In addition, the ingestion of contaminated beef is considered to be the most probable cause of development of the new variant of Creutzfeldt-Jakob disease in humans. The research on prions is still scarce although it intensified in the wake of the mad cow problem.

Localization of prions, first phase of the study

Prions are proteins that are the causative agent of transmissible spongiform encephalopathies (TSEs), a group of neurodegenerative diseases, currently without cure, that affect both animals and humans. Prion diseases are characterized by the accumulation in the brain of the pathogenic form (PrPsc) of a normal protein (PrPc) present in all mammals. For the disease to develop and manifest, the presence of PrPc in the host tissues is indispensable. In addition, in TSEs of infectious origin, it is necessary for the pathogen to enter the organism. Although there are several possible routes of entrance of the pathogen, it has always been suggested that the main route is oral via ingestion of contaminated food. Once the pathogenic form has entered, it spreads and accumulates, transforming the existing PrPc. However, it is still unknown how exactly this process takes place, i.e. how the protein manages to cross the digestive wall, contact the PrPc, transform it and finally reach the brain, where it causes damage. In order to decipher the keys to this process, it is very important to know the exact location of PrPc in the digestive wall, and this is what the work researchers have done.

The results obtained in rat have been recently published in the American Journal of Histochemistry and Cytochemistry. Those obtained in monkey and cow have been presented at the congress European Comparative Endocrinology Meeting and have been accepted for publication in the Annals of the New York Academy of Sciences.

The work, which responds to an express request from the Department of Agriculture of the Government of Navarra to the University of Navarra, has been carried out at the department of Histology and Pathology Anatomy and has been co-funded by both institutions.