NR AXNX
AU Hamilton,S.; Dagleish,M.P.; Gonzalez,L.; Siso,S.; Hope,J.; Reid,H.W.; Pang,Y.; Eaton,S.L.; Finlayson,J.; Steele,P.J.; Chianini,F.; Jeffrey,M.
TI Degradation of Abnormal PrP in Isolated Gut Loops of Sheep Challenged with Scrapie or BSE
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Pathology and Pathogenesis P03.84
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
It is commonly assumed that the natural transmission of BSE in cattle and scrapie in sheep are both via the oral route. In previous studies we have suggested that substantial amounts of abnormal PrP may be digested in the intestine. The aims of this study were to investigate the temporal degradation and absorption of abnormal PrP after inoculating scrapie and BSE sheep brain homogenates directly into the intestine.
Ileal gut loops (2 or 4 per animal) were isolated surgically and inoculated with either 10% bovine BSE or 10% sheep scrapie brain homogenate (in 0.32M sucrose solution), or with normal cattle or sheep brain homogenate, respectively. Gut loops were either flushed to eliminate gut contents or left with alimentary fluids in place prior to inoculation. Intestine and loop contents were collected after time intervals of 15 minutes to 24 hours and subjected to immunohistochemistry and Western blot analysis to determine the amount of PrPd or PrPres remaining. In agreement with previous studies of sheep scrapie, immunohistochemistry detected absorption of BSE PrPd to submucosal lymphatics. However, the abundance of BSE PrPd and its short survival, suggested most was digested. Less BSE PrPd was detected than scrapie PrPd. When incubated with gut contents, Western blot analyses suggested that the amount of BSE PrPres appeared to be reduced significantly after 15 minutes, while scrapie PrPres levels showed little reduction after 30 minutes. However, a gradual loss of PrPres over longer time periods was found in flushed guts for both cases.
These data suggest that although some abnormal PrP in brain homogenates may undergo transluminal transportation, most is digested by alimentary fluids in situ. Overall, there appeared to be a greater rate of digestion of BSE PrPres compared to scrapie PrPres. These data give a preliminary understanding of what happens to abnormal PrP protein after oral challenge.
AD S. Hamilton, M.P. Dagleish, H.W. Reid, Y. Pang, S.L. Eaton, J. Finlayson, P.J. Steele, F. Chianini, Moredun Research Institute, UK; L. González, S. Sisó, J. Hope, M. Jeffrey, Veterinary Laboratory Agency, Lasswade, UK
SP englisch
PO Schottland
EA pdf-Datei und Poster (Reihenfolge der Posterautoren geändert; Postertitel: Degradation of Scrapie and BSE PrRres in the Isolated Gut Loops of Sheep)