Enhancement of protective immune responses induced by Toxoplasma gondii dense granule antigen 7 (GRA7) against toxoplasmosis in mice using a prime-boost vaccination strategy

► T. gondii GRA7 was a prominent vaccine antigen against toxoplasmosis. ► The recombinant plasmids of pEGFP-GRA7 and pET30-GRA7 were constructed. ► A heterologous DNA prime-protein boost enhanced humoral and Th1 immune responses to GRA7. ► Mice immunized with DNA prime-protein boost regime showed significant survival rate.