Protective effect of a naked DNA vaccine cocktail against lethal toxoplasmosis in mice.
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.
Fachado
Alberto
A
Laboratory of Autoimmunity and Immunoregulation, Department of Immunology, Oswaldo Cruz Institute, Fiocruz. Av Brasil, 4365, Rio de Janeiro 21045-900, Brazil.
Rodriguez
Alexandro
A
Angel
Sergio O
SO
Pinto
Diamar C
DC
Vila
Iviane
I
Acosta
Armando
A
Amendoeira
Regina R
RR
Lannes-Vieira
Joseli
J
D000818:Animals; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016052:Protozoan Vaccines / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000517:prevention & control*; D014611:Vaccination; D019444:Vaccines, DNA / Q000276:immunology*
D016052:Protozoan Vaccines; D019444:Vaccines, DNA; D007371:Interferon-gamma