NR AWNS
AU Simmons,M.M.; Simmons,H.A.; Lockey,R.; Konold,T.; Spencer,Y.I.; Spiropoulos,J.; Clifford,D.
TI Phenotype is preserved following experimental transmission of atypical scrapie to sheep
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 PR-30
PT Konferenz-Poster
AB Active surveillance for transmissible spongiform encephalopathies in small ruminants has been an EU regulatory requirement since 2001. A number of European countries have subsequently reported cases of atypical scrapie, similar to previously published cases from Norway (Nor98). These cases have pathological and molecular features which are distinct from classical scrapie. They display a relative absence of PrP immunolabelling in the diagnostic 'obex' region of the brainstem, with pronounced immunolabelling in the cerebellum, together with a distinctive banding profile on Western blot with a prominent low molecular weight band at approximately 12 kD. Most cases have occurred singly in flocks, and are associated with genotypes considered to be more resistant to classical disease (i.e. UK National Scrapie Plan groups 1-3). Experimental transmissibility of such isolates has been reported in certain ovinised transgenic mice, but has not previously been demonstrated in the natural host. This report presents the successful transmission, following intracerebral inoculation, of atypical scrapie (from an AHQ/AHQ fallen stock sample) to a recipient sheep of homologous genotype. Clinical end-stage was reached 378 days post inoculation, and the affected animal presented with weight loss, altered behaviour and compulsive circling, but no pruritis. There was full preservation of both the pathological and molecular characteristics of the donor. The transmission characteristics of this isolate in Tg338 mice are indistinguishable from those reported for Nor98. This finding strengthens the opinion that these cases result from a distinct and stable strain of scrapie agent which may require different regulatory controls.
AD M.M. Simmons, R. Lockey, T. Konold, Y.I. Spencer, J. Spiropoulos: Department of Pathology, Woodham Lane, New Haw, Addlestone, Surrey, UK; H.A. Simmons, D. Clifford: Animal Services Unit, Woodham Lane, New Haw, Addlestone, Surrey, UK. E-mail: m.m.simmons@vla.defra.gsi.gov.uk
SP englisch
PO Italien