Volume 15, Number 9—September 2009
Research
Susceptibilities of Nonhuman Primates to Chronic Wasting Disease
Table 2
Monkey no. | PrP genotype† | CWD inoculum | Titer inoculated‡ | Incubation period, mpi§ | Weight change, % |
---|---|---|---|---|---|
303¶ | NT | MD-1 | 1.5 × 109 | 69 | –25 |
360 | A | MD-1 | 1.5 × 109 | NS (69) | +6 |
588 | C | MD-3 | 9.6 × 107 | NS (52) | +5 |
629 | B | MD-3 | 9.6 × 107 | NS (52) | 0 |
631 | A | Elk-1 | 1.9 × 108 | NS (52) | 0 |
335 | NT | Elk-2 | 6.0 × 108 | NS (69) | –5 |
656 | B | Elk-2 | 6.0 × 108 | NS (52) | –5 |
614# | A | Elk-2 | 6.0 × 108 | 44 | –10 |
317 | C | Elk-3 | 3.9 × 108 | NS (69) | 0 |
301** | NT | Elk-3 | 3.9 × 108 | 39 | –14 |
307 | A | WTD-1 | 1.2 × 109 | NS (69) | +8 |
345†† | A | WTD-1 | 1.2 × 109 | 69 | –33 |
626 | NT | WTD-2 | 1.9 × 108 | NS (52) | +11 |
641 | B | WTD-2 | 1.9 × 108 | NS (52) | 0 |
325 | NT | WTD-2 | 1.9 × 108 | NS (69) | –8 |
655 | A | Buffer control | NS (52) | –6 | |
314 | NT | Normal elk | NS (69) | +7 |
*CWD, chronic wasting disease; PrP, prion protein; mpi, months postinfection; NT, not tested (sequenced); NS, no signs.
†See Table 4 for a description of genotypes A, B, and C.
‡Infectivity titers were determined by using endpoint dilution titer in transgenic deer expressing mouse PrP and are listed as the 50% infectious dose/g of brain administered over 5 d at 2–6-d intervals.
§Incubation periods for monkeys with clinical wasting are indicated as mpi in parentheses. NS indicates that these monkeys did not show any clinical signs compatible with transmissible spongiform encephalopathy (TSE) or wasting.
¶Monkey 303 was euthanized at 69 mpi because of signs of wasting, weakness, and anorexia.
#Monkey 614 was euthanized at 44 mpi because of complications arising from anesthesia for routine tuberculosis testing. No signs of TSE were observed before the complications, and Western blot and immunohistochemical results showed that this monkey was negative for protease-resistant PrP (PrPres).
**Monkey 301 was euthanized at 39 mpi after a brief illness with signs of lethargy, anorexia, and dehydration. PrPres was detected in peripheral lymphoid tissues but not in brain.
††Monkey 345 was found dead at 69 mpi. Brain, spleen, and lymph nodes were positive for PrPres by Western blot.