NR AORP
AU Davis,L.A.; Chaplin,M.J.; Terry,L.A.; Clark,J.K.; Bramwell,J.E.; Webb,P.; Stack,M.J.
TI Correlation study of results obtained using immunohistochemistry and a sodium phosphotungstate-based Western immunoblotting technique, as applied to non-neural tissues from scrapie-affected sheep
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - DG-66
PT Konferenz-Poster
AB
Western immunoblotting (WB) techniques are routinely, and successfully, applied to brain tissue to detect PrPsc for the diagnosis of transmissible spongiform encephalopathies (TSE's). Several WB protocols have shown promising results for non-neural tissues from sheep-scrapie tissue and preliminary studies on tonsils, spleen, lymph nodes and distal ileum suggest that although PrPsc can be detected sporadically, low test sensitivity is a limiting factor. Sodium phosphotungstate (NaPTA) precipitation has been shown to enhance PrPsc extraction for some applications (Safar et al 1998, Wadsworth et al, 2001) and at VLA we have successfully developed a WB method incorporating a NaPTA precipitation step (NaPTA-WB). As immunohistochemistry (IHC) is considered the current gold standard method for the detection of PrPsc in non-neural tissues a correlation study of the results obtained for NaPTA-WB and IHC was instigated.
Results were compared for spleen, mesenteric lymph node and distal ileum from a total of 286 sheep (206 suspect scrapie submissions and 80 negative control sheep derived from New Zealand). The clinically suspect sheep were of various breed, age and genotype and all but six sheep were positive by statutory testing of the brain tissue by histopathology, IHC and WB.
Our results showed 100% correlation between the two methods where tissue was available for both tests. The results suggest that genotype may have an effect on the pathogenesis of scrapie. Sheep with the VRQ/ARR genotype had reduced lymphoreticular involvement compared to other genotypes. However, the possibility of a different agent strain in these sheep cannot be entirely dismissed.
AD L.A. Davis, M.J. Chaplin, L.A. Terry, J.K. Clark, J.E. Bramwell, P. Webb, M.J. Stack, Veterinary Laboratories Agency (VLA), UK
SP englisch
PO Deutschland