NR AWFA
AU Fournier,J.G.; Adjou,K.T.; Ouidja,I.; Ruchoux,M.M.; Deslys,J.P.
TI Ependymal cells in scrapie infection
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions CE-15
PT Konferenz-Poster
AB During the course of infection in the hamster scrapie model, the ependyma epithelium shows immunostaining of PrPsc in the subependymal layer and at the apical ependymal cell borders. In order to specify the interaction of ependymal cells with the scrapie agent, we used electron microscopy in combination with PrP immuno-detection in hamsters infected with the 263K scrapie strain. In this model we have previously shown that reactive astrocytes localized at the injection site appear to be the first cells propagating the agent in the brain. They contained lysosomal-like organelles positive for PrP. Interestingly, similar PrP-positive organelles were detected in ependymal cells suggesting an interaction between this cell type and the scrapie agent. In addition, PrP labelling associated with vesicular and multivesicular endosomal structures was observed in the ependymal cell cytoplasm close to the apical cell membrane. Examining the relationship between ependymal cell microvillosities and PrPsc, immunogold PrP labelling was found to be associated with either morphologically intact microvillosities and altered structures having a relationship with PrP fibrillar elements present in the intraventricular space. In contrast, ependymal cell cilia were completely devoid of PrP immunogold labelling. Following a careful morphological analysis, small electron-dense particles were observed in close association with the membrane of ependymal cell microvillosities and fibrillar elements. Particles could also be observed in subependymal plaque-like accumulations of PrPsc. These structures of about 15 nm in diameter showing a coma shape were present intracellularly in the apical zone of the ependymal cell cytoplasm but were never observed in ependymal cells of non-infected brains. They could represent a morphological aspect of the infectious agent in situ in the brain. These findings suggest a strong implication of the ependymal cells in the production of the scrapie agent in the central nervous system, indicating that this particular glial cell type is involved in the pathophysiological mechanisms of scrapie infection.
AD J.G. Fournier, M.M. Ruchoux, J.-P. Deslys: CEA/DSV/DRM/GIDTIP,Fontenay aux Roses 92260 France; K. Adjou: Ecole Vétérinaire Maison Alfort France; I. Ouidja: CEA/DSV/DRM/GIDTIP,Fontenay aux Roses 92260 France, and Ecole Vétérinaire Maison Alfort France. E-mail: jeanguy.fournier@cea.fr
SP englisch
PO Italien