Protective efficacy of Toxoplasma gondii GRA12 or GRA7 recombinant proteins encapsulated in PLGA nanoparticles against acute Toxoplasma gondii infection in mice

Background Toxoplasma gondii is an apicomplexan parasite that affects the health of humans and livestock, effective vaccine urgently required. Nanoparticles can modulate improve cellular humoral immune responses. Methods In current study, poly (D, L-lactic-co-glycolic acid) (PLGA) nanoparticles were used as a delivery system for T. dense granule antigens GRA12 GRA7. BALB/c mice injected with vaccines protective efficacy was evaluated. Results Mice immunized PLGA+GRA12 exhibited significantly higher IgG, noticeable predominance IgG2a over IgG1 also observed. There 1.5-fold level lymphocyte proliferation in PLGA+GRA12-injected compared to Alum+GRA12-immunized mice. Higher levels IFN-g IL-10 lower IL-4 detected, indicating Th1 Th2 responses induced but predominant response Th1. no significant differences between Alum+GRA7-immunized PLGA+GRA7-immunized groups. Immunization these four resulted reduced loads, they lowest PLGA+GRA12-immunized The survival times longer than those other vaccinated Conclusion study indicated recombinant protein encapsulated PLGA promising against acute toxoplasmosis, almost useless enhancing by GRA7 protein.