Related Experiment Video
Updated: Jul 12, 2026

Forward Genetics Screens Using Macrophages to Identify Toxoplasma gondii Genes Important for Resistance to IFN-γ-Dependent Cell Autonomous Immunity
Published on: March 12, 2015
GRA7 provides protective immunity in cocktail DNA vaccines against Toxoplasma gondii
E Jongert1, S de Craeye, J Dewit
1Toxoplasma Research Unit, WIV-Pasteur Institute of Brussels (Federal Service of Public Health), Brussels, Belgium. ejongert@pasteur.be
Abstract:
In a previous study, single-gene vaccination with GRA1, GRA7 or ROP2 was shown to elicit partial protection against Toxoplasma gondii. In this study, the contribution of each antigen in the evoked humoral and cellular immune responses was evaluated after vaccination with plasmid mixtures containing GRA1, GRA7 and ROP2. Cocktail DNA vaccinated mice developed high antibody titers against the antigens from two-gene DNA vaccine cocktails, but lower titres when immunized with the three-gene cocktail. High numbers of IFN-gamma secreting splenocytes were generated predominantly against GRA7. Brain cyst burden was reduced by 81% in mice vaccinated with the three-gene mixture and they were completely protected against acute toxoplasmosis. Similar high levels of brain cyst reductions were obtained after vaccination with cocktails composed of GRA1 and GRA7 (89% reduction), or GRA7 and ROP2 (79% reduction), but not with the cocktail composed of GRA1 and ROP2. In low dose single-gene vaccinations, IFN-gamma and strong protection could only be elicited by GRA7. Hence, the presence of GRA7 in the DNA vaccine formulation was important for optimal protection and this was correlated with GRA7-specific IFN-gamma production. We propose GRA7 as a main component in cocktail DNA vaccines for vaccination against T. gondii.
Related Concept Videos
Toxoplasmosis
Bacterial Toxins
Types of Toxins
Air pollutants, primarily gases, pose significant threats to respiratory health, leading to conditions like hypoxia, lung cancer, and in extreme cases, death.
Environmental pollutants like...
Vaccinations
Antigens Involved in Adaptive Immunity
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
Diphtheria

