title: Scrapie infectivity and proteinase K-resistant prion protein in sheep placenta, brain, spleen, and lymph node: implications for transmission and antemortem diagnosis.
abstract: Probable transmission of bovine spongiform encephalopathy to humans has focused intense interest on all of the transmissible spongiform encephalopathies (TSEs) and how they spread. In all TSEs, an abnormal disease-associated, proteinase K-resistant protein referred to as PrP-res or PrPsc accumulates in brain. In some species, PrP-res accumulates in other tissues as well. Sheep placenta, brain, spleen, and lymph node were analyzed in detail for PrP-res and infectivity. Both were detected in all brain and spleen samples and in placenta and lymph nodes of 80% of the scrapie-infected sheep. A perfect correlation was observed between infectivity and PrP-res detection. These results substantiate the probability that placenta plays an important role in natural transmission of scrapie, suggest that analysis of placenta for PrP-res could be the basis for an antemortem test for sheep scrapie, and show that PrP-res, scrapie infectivity, and scrapie disease are closely associated.
authors.affiliation: Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, 59840, USA. Rrace@atlas.niaid.nih.gov
authors.forename: R
authors.initials: R
authors.lastname: Race
authors.forename: A
authors.initials: A
authors.lastname: Jenny
authors.forename: D
authors.initials: D
authors.lastname: Sutton
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D019286:Endopeptidase K / Q000378:metabolism; D005260:Female; D008198:Lymph Nodes / Q000737:chemistry; D010920:Placenta / Q000737:chemistry*; D018620:PrPSc Proteins / Q000302:isolation & purification* / Q000378:metabolism; D012608:Scrapie / Q000175:diagnosis* / Q000635:transmission*; D012756:Sheep; D013154:Spleen / Q000737:chemistry; D014018:Tissue Distribution
chemical_list: D018620:PrPSc Proteins; D019286:Endopeptidase K