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Volume 31, Number 12—December 2025

Research

Silent Propagation of Classical Scrapie Prions in Homozygous K222 Transgenic Mice

Natalia Fernández-Borges1, Alba Marín-Moreno1, Juan Carlos Espinosa, Sara Canoyra, Olivier Andréoletti, and Juan María TorresComments to Author 
Author affiliation: Centro de Investigación en Sanidad Animal (CISA-INIA-CSIC), Madrid, Spain (N. Fernández-Borges, A. Marín-Moreno, J.C. Espinosa, S. Canoyra, J.M. Torres); Interactions Hôte Agent Pathogène–École Nationale Vétérinaire de Toulouse, Toulouse, France (O. Andréoletti)

Main Article

Table 1

Isolates used in study of classical scrapie prions in homozygous K222 transgenic mice*

Category Isolate Species Origin Goat PrP genotype† Description Supplier
I
 198/9
 Sheep
 Italy
 wt; S240S
 Classical scrapie isolate from a naturally infected sheep
 ISS
II S2 Goat Spain wt; S240P Classical scrapie isolate from a naturally infected goat UNIZAR
CP060146 (22) Goat France wt Classical scrapie isolate from an experimentally infected goat ENVT
CP060146/K222 (22)
 Goat
 France
 K222
 Classical scrapie isolate from an experimentally infected goat
 ENVT
II + III UKA2 Goat United Kingdom wt; S240P Classical scrapie isolate from a naturally infected goat APHA
F14
 Goat
 France
 wt; I142M, S240P
 Classical scrapie isolate from a naturally infected goat
 INRA
IV F10 Goat France wt; S240P Classical scrapie isolate from a naturally infected goat INRA
C1
 Goat
 Cyprus
 wt
 Classical scrapie isolate from a naturally infected goat
 VS
Negative control Healthy goat brain Goat France wt Brain from a noninfected goat INRA

*Isolates were classified as previously described (31) on the basis of prion biochemical features when transmitted in transgenic mice expressing the bovine PrP (Bo-Tg110) and biologic features transmitted in mice expressing the ovine PrP (Q222-Tg501). APHA, Animal and Plant Health Agency, Surrey, United Kingdom; ENVT, École Nationale Vétérinaire Toulouse, Toulouse, France; INRA, French National Institute for Agricultural Research, Nouzilly, France; ISS, Istituto Superiore di Sanitá Animal, Rome, Italy; UNIZAR, Universidad de Zaragoza, Spain; VS, Veterinary Services, Nicosia, Cyprus; wt, wild-type. †The wt goat prion protein genotype is A136R154P240/A136R154P240. S240S, S240P and I142M refer to polymorphisms at specific codons of the PRNP gene.

Main Article

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1These first authors contributed equally to this article.

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