Immunization of BALB/c Mice with Killed Tachyzoites of against Acute Toxoplasmosis.

BACKGROUND

with widespread distribution infects over one third of human populations in the world and can cause serious life-threatening diseases especially for the immunodeficient patients in acute toxoplasmosis. As the clinical pharmaceutical drugs with severe side effects for treatment and non-ideal extant vaccines for prevention, more work starves to be done for keeping advantages in the athletics.

METHODS

Aluminum adjuvant and hybrid formaldehyde-killed tachyzoites of RH and GT1 isolates were prepared to intramuscularly immunize BALB/c mice for five times at 0, 3, 7, 14 and 21 days post first injection. The triggered humoral and cellular immune responses at two weeks post the last immunization and the survival times of infected mice were examined for the hybrid immunization scheme judgement.

RESULTS

The anti-RH and anti-GT1 specific antibodies were both increased at one week prior to challenge ( < 0.05), and the survival times of immunized mice (7.33 ± 0.71 d for RH, 7.22 ± 0.97 d for GT1) against acute toxoplasmosis were significantly prolonged by the immunizations performed in the study compared to blank control (6.67 ± 0.50 d for RH, 6.33 ± 0.71 d for GT1; < 0.05), with the higher IFN-γ, IL-2 and IL-12p70 in sera, the elevated CD3eCD4 T and CD3eCD8a T cells, and the enhanced lymphocyte proliferation in spleen ( < 0.05).

CONCLUSION

The hybrid killed tachyzoites with aluminum adjuvant induced humoral and cellular immune responses of mice, and offered mildly protective efficacy against acute toxoplasmosis.