TABLE 2.
Protection of CBA/J mice against T. gondii oral infectiona
| Immunization | Dose (no. of cysts) | Mean no. of brain cysts ± SD | % Reduction |
|---|---|---|---|
| Expt 1 | 70 | ||
| pcDNA3 | 7,059 ± 2,047 | ||
| pMIC3i | 2,966 ± 1,756b | 58 | |
| Expt 2 | 70 | ||
| pcDNA3 | 5,468 ± 1,048 | ||
| pMIC3i | 3,048 ± 911b | 45 | |
| pMIC3i + pGM-CSF | 1,839 ± 781b | 67 | |
| Expt 3 | 70 | ||
| pcDNA3 | 6,109 ± 829 | ||
| pMIC3i | 2,600 ± 936b | 57.5 | |
| pMIC3i + pGM-CSF | 1,652 ± 494b | 73 | |
| Expt 4 | 70 | ||
| pcDNA3 | 5,088 ± 1,064 | ||
| pMIC3i + pGM-CSF | 1,349 ± 362b | 74 |
a
The mice were immunized with 50 μg of pMIC3i alone or combined with 50 μg of pGM-CSF on days 0 and 14 and then boosted with 50 μg of pMIC3i on day 28. The vaccinated mice (nine per group) were orally challenged with 70 cysts of T. gondii strain 76K 2 weeks after the last immunization. The brain cyst load was determined 1 month after the challenge. Mice inoculated with empty plasmid pcDNA3 were used as controls.
b
P < 0.001 with respect to control.