Table 2.
Prion load in brains and spleens of individual tg640 mice
|
|
|
Transmission of brain to indicator mice |
Transmission of spleen to indicator mice |
||||
|---|---|---|---|---|---|---|---|
| Mouse genotypes |
Days after inoculation; route of infection |
Brain infectivity (logLD50 per gram) |
Attack rate (mean ± SD days) |
Spleen infectivity (logLD50 per gram) |
Attack rate (mean ± SD days) |
||
| MBP-PrP | 35 d; intraperitoneal | <1.5 | 0/4 | <1.5 | 0/4 | ||
| <1.5 | 0/4 | <1.5 | 3/4 (99,148,150)a | ||||
| 140 d; intraperitoneal | <1.5 | 0/4 | <1.5 | 0/4 | |||
| <1.5 | 0/4 | <1.5 | 0/4 | ||||
| 210 d; intracerebral | <1.5 | 0/4 | <1.5 | 0/4 | |||
| <1.5 | 0/3 | <1.5 | 0/4 | ||||
| Prnp+/+ | 35 d; intraperitoneal | <1.5 | 0/4 | 5.0 | 4/4 (73 ± 5) | ||
| <1.5 | 0/4 | 5.1 | 4/4 (72 ± 4) | ||||
| 140 d; intraperitoneal | 5.3 | 4/4 (68 ± 6) | 4.0 | 3/3 (84 ± 4) | |||
| 4.9 | 4/4 (74 ± 7) | 5.1 | 4/4 (72 ± 8) | ||||
| 167 d; intracerebral | 6.3 | 4/4 (58 ± 6) | 5.1 | 4/4 (72 ± 5) | |||
| 6.1 | 4/4 (60 ± 7) | 5.3 | 4/4 (70 ± 2) | ||||
| Prnpo/o | 42 d; intraperitoneal | <1.5 | 0/4 | <1.5 | 0/4 | ||
|
|
|
<1.5 |
0/4 |
<1.5 |
1/4 (99) |
||
Wild-type (Prnp+/+) and tg640 mice homozygous for the MBP-PrP transgenic cluster were inoculated intraperitoneally and intracerebrally and killed for analysis at the time points indicated.
a
Prion disease in three of four tga20 indicator mice that had received spleen extracts from a 35 dpi-challenged tg640 mouse is most likely a result of prions persisting from the inoculum.