NR AWOI
AU Stack,M.J.
TI Discrimination between CWD, BSE and scrapie by molecular profiling
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre, Workshop of the Neuroprion Cervid Group - Chronic Wasting Disease (CWD): Current knowledge and European perspective 2006, 3.10.2006
PT Konferenz-Vortrag
AB If CWD in cervids was discovered in Europe one of the first questions would be whether there could have been contact with the agents of BSE or scrapie. Techniques which can discriminate between experimental BSE in sheep, and natural scrapie cases are now available to examine any positive cases which may arise from extended surveillance. Studies using a modified version of the Prionics(R)Check WESTERN blot have shown differences in the electrophoretic mobility of the PrPres protein bands, in particular the molecular weight of the unglycosylated protein band, which is higher for scrapie samples than for sheep experimentally infected with BSE. Discrimination is also possible by parallel testing using two monoclonal antibodies (mAbs). MAb 6H4, is raised in mice to human PrP (amino acid sequence 144-152) and detects PrPres in cattle and sheep; the second, is mAb P4, (ovine PrP sequence 89-104), which is more selective for scrapie PrPres. The basis for discrimination is the location of the N-terminal cleavage site for proteinase K digestion, whereby a short amino acid sequence remains intact in sheep scrapie samples, but not in the BSE samples. When the molecular profiles for a limited number of CWD samples were examined a different molecular weight profile to scrapie and BSE was obtained with the unglycosylated band molecular weights being higher than both, irrespective of whether they were derived from elk, mule deer or white-tailed deer. Application of a wider range of discriminatory tests which utilise this parallel testing may indicate whether CWD in cervids is a single "strain", independent from BSE and scrapie.
AD TSE Molecular Biology Department, Veterinary Laboratories Agency, Weybridge, United Kingdom. E-mail: m.j.stack@vla.defra.gsi.gov.uk
SP englisch
PO Italien