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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 3

Transmission of classical scrapie isolates to K222-Tg516 homozygous mice in study of classical scrapie prions in homozygous K222 transgenic mice*

Category Isolate 1st passage
 2nd passage
Mean survival time + SD, d No. diseased and PrPres-positive/no. inoculated Mean survival time + SD, d No. diseased and PrPres-positive/no. inoculated
I
 198/9
 >650
 1/6†
ND
 NA
II S2 >650 3/4† >650 7/7†
CP060146 >650 5/5† >650 5/5†
CP060146/K222 goat
 >650
 4/4†
>650
 6/6†
II + III UKA2 >650 4/4† >650 5/5†
F14
 >650
 4/4†
>650
 5/5†
IV F10 >650 6/6† >650 5/5†
F10/K222-Tg516 >650 5/5† >650 6/6†
C1
 >650
 7/7†
ND
 NA
Negative control Healthy goat brain >650 0/6† >650 0/6†

*NA, not available; ND, not done; PrPres, proteinase K-resistant PrP. †Animals were found dead or euthanized at the end of their lifespan without showing clinical signs of classical scrapie.

Main Article

1These first authors contributed equally to this article.

Page created: November 17, 2025
Page updated: December 23, 2025
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