Protective Effect of a naked DNA vaccine cocktail against lethal Toxoplasmosis in mice

FACHADO, A.; RODRIGUEZ, A.; SERGIO OSCAR ANGEL; PINTO, D.; VILA, I.; ACOSTA, A.; AMENDOEIRA, MRR; LANNES-VIEIRA, J.

VACCINE

ELSEVIER SCI LTD

Año: 2003 vol. 21 p. 1327 - 1335

0264-410X

BALB/c mice were intramuscularly immunized with low doses (25-50microg) of DNA cocktail containing plasmids encoding the full-length SAG1/P30 and the 196-561 terminal sequence of ROP2 genes. This immunization resulted in a Th1-type response with predominance of IgG2a and a specific T-cell proliferation with high levels of interferon-gamma (IFN-gamma) secretion, whereas no IL-4 was detected. Moreover, DNA cocktail immunization induced a long-lasting protection against a lethal challenge with the highly virulent Toxoplasma gondii RH strain, whereas low doses of single genes were not protective. These results support further investigations to achieve a multigene anti-T. gondii DNA vaccine.