Rapid PrP super(Sc) Detection in Lymphoid Tissue and Application to Scrapie Surveillance of Fallen Stock in Japan: Variable PrP super(Sc) Accumulation in Palatal Tonsil in Natural Scrapie

Rapid western blot (WB) procedure for an abnormal isoform of prion protein (PrP super(Sc) ) detection in lymphoid tissues was established and has been applied to the surveillance of fallen stock. In this program, brain and palatal tonsil were examined by WB and three cases of sheep scrapie were detected. While one clinically scrapie-infected sheep harbored PrP super(Sc) in the brain and palatal tonsil, the two sheep in the pre-clinical stage harbored PrP super(Sc) in the brain, but not in the palatal tonsil. This study shows that PrP super(Sc) accumulation in palatal tonsil is variable in natural scrapie, even among genetically susceptible sheep.