NR AXQW
AU Lantier,F.; Berthon,P.; Lantier,I.; Barc,C.; Sarradin,P.; Rossignol,C.; Bernardet,P.; Leroux,H.; Bernard,S.; Lacroux,C.; Grassi,J.; Simmons,H.A.; Shelcher,F.; Elsen,J.M.; Andreoletti,O.
TI Genetic Susceptibility of Sheep to Experimental BSE Transmission
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Pathology and Pathogenesis P03.38
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
Susceptibility to Transmissible Spongiform Encephalopathy has been shown to be genetically controlled by the PRNP gene in small ruminants, mouse and human. A genetic selection for the resistant A136R154R171 allele is underway in sheep at a European scale. The influence of the PRNP gene on BSE transmission in sheep is strategic for the control of this disease. Experimental BSE inoculations were performed by intracerebral and oral routes in susceptible and resistant New Zealand TSE free sheep at various ages. Possibilities of horizontal and vertical transmission were tested using sentinels or pregnant ewes. Animals were sacrificed in kinetics or at time of clinical disease and their tissues tested by immunohistochemistry, immunochemical assays and inoculation into RIII and Tgbov mice.
The incubation period of ARR/ARR sheep inoculated intracerebrally was much longer (7/10 positives, 1383 days +/- 83) that the one of ARQ/ARQ sheep (9/9 positives, 477 days +/- 33). After oral inoculation at birth, PrPres deposits were detected from 4 months of age in lymphoid and nervous tissues of ARQ/ARQ lambs. Their incubation period was 19 months whereas sheep carrying the ARR allele are still alive at 46 months. However, one 10 months old ARR/ARR sheep had PrPres deposits and carried infectivity in its spleen. Two sentinel ARQ/ARQ ewes contracted the disease with an incubation period of 23 months evidencing the possibility of horizontal transmission of BSE in sheep flocks. Lymphoid and nervous PrPsc positive tissues transmitted the BSE strain in mice with minor modifications of their western blot and lesion profiles.
The results evidence the global stability of the BSE strain after two passages in sheep, its short incubation period in this species even after oral transmission and the relative resistance to TSEs of sheep carrying the ARR allele with the limitation of their possible carrier status.
AD F. Lantier, P. Berthon, I. Lantier, C. Barc, P. Sarradin, C. Rossignol, H. Leroux, S. Bernard, INRA Centre de Tours, France; P. Bernardet, INRA Centre de Tours, Plate-Forme d'Infectiologie Experimentale; C. Lacroux, F. Shelcher, O. Andreoletti, Ecole Nationale Veterinaire de Toulouse, IHAP-UMR INRA/ENVT, France; J. Grassi, CEA-Saclay, France; H.A. Simmons, VLA Weybridge, UK; J.M. Elsen, INRA centre de Toulouse, France
SP englisch
PO Schottland