NR AWJR
AU Marruchella,G.; Ligios,C.; Uras,P.; Zucca,R.; Lalatta-Costerbosa,G.; Chiocchetti,R.; Clavenzani,P.; Mazzoni,M.; Albanese,V.; D'Agostino,C.; Borroni,R.; Vaccari,G.; De Grossi,L.; Rosone,F.; Aguzzi,A.; Di Guardo,G.
TI Natural and oral experimental scrapie infection in Sarda breed sheep: a comparative pathogenic study on ileal enteric nervous system plexuses
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 PA-35
PT Konferenz-Poster
AB
The enteric nervous system (ENS) plays a key role in the early pathogenesis of sheep scrapie, but no information exists on the ENS cytotypes which are progressively involved during infection, nor on their morphofunctional changes in comparison with those affecting central nervous system neurons. We investigated the ileal myenteric plexuses (MPs) and submucosal plexuses (SMPs) of 49 Sarda breed sheep carrying different PrP genotypes (ARQ/ARQ, ARQ/AHQ, ARQ/ARR, ARR/ARR), 33 of which had been orally dosed with scrapie at either 8 (28 animals) or 1.5 months of age (5 animals) and subsequently euthanized at definite time intervals post-infection (p.i.), while 16 undosed sheep served as normal healthy control animals. The ileal MPs and SMPs from 7 additional ARQ/ARQ Sarda breed sheep clinically affected with natural scrapie were also investigated. PrPsc immunoreactivity (IR), along with neuronal protein Hu C/D, neuronal nitric oxide synthase, calbindin and glial fibrillary acidic protein IR, were evaluated by immunohistochemistry (IHC) and indirect immunofluorescence (IF) on paraffin sections and suitable wholemount preparations. All 7 natural scrapie-affected sheep showed IHC and IF evidence of PrPsc in both their brain tissue (obex region) and ENS plexuses. The same was true, in experimentally infected animals, for 8 clinically healthy ARQ/ARQ sheep euthanized between 12 and 24 months p.i. and for additional 5 ARQ/ARQ (euthanized at 24 months p.i.) and 3 ARQ/AHQ (euthanized at 35, 36.3 and 39.5 months p.i., respectively) clinically affected sheep. PrPsc deposition, mainly involving MPs in experimentally infected animals and SMPs in naturally affected sheep, was compatible with an involvement of enteroglial cells (EGCs) and, in natural scrapie-affected animals, with a simultaneous involvement of neuronal cells, the phenotype of which is currently being characterised. On the basis of the above results, EGCs and neurons of ileal ENS plexuses are likely involved in the pathogenesis of natural and oral experimental scrapie infection in Sarda breed sheep.
Granting Institutions: Italian MIUR (PRIN 2004), University of Teramo, University of Bologna, Italian Ministry of Health.
AD G. Marruchella, V. Albanese, G. Di Guardio: Department of Comparative Biomedical Sciences, University of Teramo, Teramo, Italy; C. Ligios, P. Uras, R. Zucca: Istituto Zooprofilattico Sperimentale (IZS) della Sardegna, Sassari, Italy; G. Lalatta-Costerbosa, R. Chiocchetti, P. Clavenzani, M. Mazzoni: Department of Veterinary Morphophysiology and Animal Productions, Ozzano Emilia (Bologna), Italy; C. D'Agostino, R. Borroni, G. Vaccari: National Institute of Health, Department of Food Safety and Animal Health, Rome, Italy; L. De Grossi, F. Rosone: IZS delle Regioni Lazio e Toscana, Viterbo, Italy; A. Aguzzi: Institute of Neuropathology, University Hospital of Zürich, Zürich, Switzerland. E-mail: gdiguardo@unite.it
SP englisch
PO Italien