title: Intraepithelial and interstitial deposition of pathological prion protein in kidneys of scrapie-affected sheep.
abstract: Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE). The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrP(Sc). We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep for renal deposition of PrP(Sc) from distinct, geographically separated flocks. By performing Western blot, PET blot analysis and immunohistochemistry we found intraepithelial (cortex, medulla and papilla) and occasional interstitial (papilla) deposition of PrP(Sc )in kidneys of scrapie-affected sheep. Interestingly, glomerula lacked detectable signals indicative of PrP(Sc). PrP(Sc) was also detected in kidneys of subclinical sheep, but to significantly lower degree. Depending on the stage of the disease the incidence of PrP(Sc) in kidney varied from approximately 27% (subclinical) to 73.6% (clinical) in naturally scrapie-affected sheep. Kidneys from flocks without scrapie outbreak were devoid of PrP(Sc). Here we demonstrate unexpectedly frequent deposition of high levels of PrP(Sc) in ovine kidneys of various flocks. Renal deposition of PrP(Sc) is likely to be a pre-requisite enabling prionuria, a possible co-factor of horizontal prion-transmission in sheep.
authors.affiliation: Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy. ciriaco.ligios@izs-sardegna.it
authors.forename: Ciriaco
authors.initials: C
authors.lastname: Ligios
authors.forename: Giovanna Maria
authors.initials: GM
authors.lastname: Cancedda
authors.forename: Ilan
authors.initials: I
authors.lastname: Margalith
authors.forename: Cinzia
authors.initials: C
authors.lastname: Santucciu
authors.forename: Laura
authors.initials: L
authors.lastname: Madau
authors.forename: Caterina
authors.initials: C
authors.lastname: Maestrale
authors.forename: Massimo
authors.initials: M
authors.lastname: Basagni
authors.forename: Mariangela
authors.initials: M
authors.lastname: Saba
authors.forename: Mathias
authors.initials: M
authors.lastname: Heikenwalder
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D017931:DNA Primers; D004847:Epithelial Cells / Q000378:metabolism; D007150:Immunohistochemistry; D007668:Kidney / Q000378:metabolism*; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction; D018620:PrPSc Proteins / Q000378:metabolism*; D012608:Scrapie / Q000378:metabolism*; D012756:Sheep
chemical_list: D017931:DNA Primers; D018620:PrPSc Proteins