TABLE 2.
Bioassay for rPrP fibrils generated in QUIC reactions in wild-type micea
| Inoculum | Concn of seed PrPSc (pg/μl) | Survival period (dpi)b | Mortality (no. of dead mice/total no. tested) |
|---|---|---|---|
| 1st-rPrP-fibCh | 1 | 185.5 ± 4.0*d | 4/4 |
| Mock 1st QUIC (Ch)c | 1 | 201, 220e | 2/4 |
| 1st-rPrP-fib22L | 1 | 213.0 ± 8.9**d | 6/6 |
| Mock 1st QUIC (22L)c | 1 | 333e | 1/5 |
| 5th-rPrP-fibCh | 1 × 10−8 | >660f | 0/4 |
| Mock 5th QUIC (Ch)c | 1 × 10−8 | >660f | 0/4 |
| 5th-rPrP-fib22L | 1 × 10−8 | >660f | 0/6 |
| Mock 5th QUIC (22L)c | 1 × 10−8 | >660f | 0/6 |
| rPrP-fibspon | 0 | >660f | 0/6 |
| Second passage of 1st-rPrP-fibCh | 152.0 ± 8.5d | 5/5 | |
| Second passage of mock 1st QUIC (Ch)g | 148.4 ± 5.9d | 5/5 | |
| Second passage of 1st-rPrP-fib22L | 153.5 ± 0.6d | 5/5 | |
| Second passage of mock 1st QUIC (22L)h | 149.6 ± 10.4d | 4/4 |
Mice were intracerebrally inoculated with 40 μl of each inoculum. For the second passage, 10% BH was used.
Statistical significance was determined using the log rank test. **, P < 0.01 (compared with the controls); *, P < 0.05 (compared with the controls). dpi, days postinoculation.
After subjecting seed-only mixtures containing the same concentration of PrPSc as 1st- or 5th-rPrP-fibSc to a mock QUIC procedure, the same amount of rPrP was added. The solutions were inoculated into mice as controls for rPrP fibrils.
Data represent means ± standard deviations.
Data represent the survival periods of the TSE-positive mice. All nonsymptomatic mice were negative for PrPSc at 660 dpi.
Data represent the day postinoculation when the experiment was ended.
A sample from a mouse obtained at 201 dpi was used.
A sample from a mouse obtained at 333 dpi was used.