Conversely, in the thalamus, while preclinical scrapie-affected animals showed a trend towards upregulation of SPP1 , a significant upregulation ( p -value = 0.033) was evident in the clinical stage of the disease, compared to healthy controls.
As expected, PrP Sc immunostaining was absent in healthy animals and markedly increased in all CNS regions of clinical sheep, with significant accumulation already evident in the preclinical stage, particularly in the obex, cerebellum, hippocampus and frontal cortex, and a close-to-significant increase also observed in the thalamus of preclinical scrapie-affected sheep.
Spongiosis followed a similar pattern, showing highly significant differences between scrapie-affected and healthy animals across all regions.