The Plain and the Ugly Prion Infected Neuronal Tissue in an Experimental Animal Model; An Electron Microscopic Study.

Abstract

Abstract Transmissible encephalopathy of animals (scrapie and bovine spongiform encephalopathy) and of man (Creutzfeldt-Jacob disease, new variant Creutzfeldt-Jacob disease, Kuru, Gerstmann-Straussler-Scheinker disease and familial fatal insomnia) have been well characterized as progressive neurodegenerative diseases, often associated with spongiform degeneration, neuronal loss, reactive astrocytic gliosis and variable amyloid plaques, without any sign of an immune response or inflammatory infiltrates. Prion proteins are elements that propagate variability through multiple biologically active conformers of a host encoded sialoglycoprotein (PrPc). The agent responsible for transmissible encephalopathies is composed mainly, if not exclusively, of an isoform of PrP, designated PrPSc. Extensive information of post-mortem material has been described at the light microscopic level, where the emphasis has been on spongiform tissue and amyloid plaques. Our study provides ultrastructural observations of the central nervous system, specifically of degenerating neurons and their associated changes during the course of scrapie infection in a hamster model.