Graph of survival times (day post inoculation, dpi) and the conformational stability of PrPSc ([GdnHCl]1/2) of human and animal isolates transmitted to bank voles. Mean survival times ± SD after the third passage were: sCJD MM1, 139 ± 9; sCJD MV1, 145 ± 21; gCJD E200K, 135 ± 12; sCJD MV2, 113 ± 6 (second passage); sCJD MM2, 323 ± 24; scrapie SS7, 93 ± 5; scrapie SCR1, 73 ± 4; scrapie SCR10, 74 ± 5; scrapie SCR11, 78 ± 2 ; BSE, 92 ± 8 [28]. The [GdnHCl]1/2 values (mean ± SD) obtained by CSSA were: sCJD MM1, 2.8 ± 0.1 [11]; sCJD MV1, 2.9 ± 0.2 [11]; gCJD E200K, 2.9 ± 0.1 [11]; sCJD MV2, 2.2 ± 0.1; sCJD MM2, 1.6 ± 0.1 [11]; scrapie SS7, 2.0 ± 0.1 [11]; scrapie SCR1, 2.0 ± 0.1; scrapie SCR10, 2.1 ± 0.1; scrapie SCR11, 1.9 ± 0.2 ; BSE, 2.4 ± 0.2.