FIG. 1.
Outline of scrapie and EAE coinduction experiments. (a) Prion inocula used in coinduction experiments. A 1% brain homogenate (10−2) was inoculated i.c. or i.p. into mice to represent a high-titer prion inoculum. A 10−8 dilution of the initial inoculum was used as the low-titer inoculum. (b) Scheme of coinduction experiments. Mice were first inoculated with the designated prion inoculum (i.c., low and high titers; i.p., high titer). Thirty days later, the same mice were either induced for EAE or left untreated. Control mice were induced for EAE 30 days after inoculation with saline or normal brain homogenate.