Figure 5. Seeding activity of PrP^Sc seeds of different species in huPrP.

The box plot shows seeding activity of seeds from the species human, cattle, sheep and deer in huPrP obtained from identical replicates of single seeding experiments. Seeding activity was calculated by dividing the average of relative fluorescence of samples with PrP^Sc positive seeds and PrP^Sc negative seeds within 80-100 h (plateau phase). For seeds from CJD (N = 7) or BSE (N = 8) material a high seeding activity is observable. For seeds from scrapie (N = 10) or CWD (N = 8) a strong species barrier is apparent.