The cellular prion protein (PrPC) is a membrane-bound
glycoprotein especially abundant in the central nervous system
(CNS). The scrapie prion protein (PrPSc, also termed prions) is
responsible of transmissible spongiform encephalopathies (TSE),
a group of neurodegenerative diseases which affect humans and
other mammal species, although the presence of PrPC is needed
for the establishment and further evolution of prions.
The present work compares the expression and localization
of PrPC between healthy human brains and those suffering from
Alzheimer disease (AD).
In both situations we have observed a rostrocaudal decrease in
the amount of PrPC within the CNS, both by immunoblotting
and immunohistochemistry techniques. PrPC is higher expressed
in our control brains than in AD cases. There was a neuronal loss
and astogliosis in our AD cases. There was a tendency of a lesser
expression of PrPC in AD cases than in healthy ones. And in AD
cases, the intensity of the expression of the unglycosylated band
is higher than the di- and monoglycosylated bands.
With regards to amyloid plaques, those present in AD
cases were positively labeled for PrPC, a result which is further
supported by the presence of PrPC in the amyloid plaques of a
transgenic line of mice mimicking AD.
The work was done according to Helsinki Declaration of
1975, and approved by the Ethics Committee of the Faculty of
Medicine of the University of Navarre