Standard Scrapie Cell Assay in the presence of various prion inhibitors (ECPA) of AMO10- and 2E4-derived RML prions after propagation in mice.

Swa-resistant AMO10-derived prions, swa-dependent 2E4-derived prions and authentic brain-derived RML prions were propagated in C57BL6 mice and analyzed by ECPA on PK1 cells in the absence (blue line) or presence of either swa (red, dashed line) or kifu (green, dashed line). RIs are the reciprocals of the dilutions required to yield 500 PrP^res positive cells per 20000 cells. Q_drug = RI/RI_+drug indicates the inhibitory effect of the drug on the RI of a prion sample and may be compared with the Q_drug value of brain-derived RML prions. A. Brain-passaged AMO10-derived prions (, ) were sensitive to swa, but semi-resistant to kifu. B. Brain-passaged 2E4-derived prions were inhibited by swa, however, one sample (<2E4-brain-c>) contained prions that were semi-resistant to kifu, one sample (<2E4-brain-b>) contained kifu-sensitive prions, and one sample (<2E4-brain-a>) contained prions that were strongly inhibited by kifu. C. Two experimental control brains (brain1 and brain2) of mice that were inoculated with authentic RML prions and a homogenate of pooled brains (lab stock) were analyzed as controls; the prions were swa-sensitive and strongly inhibited by kifu.