FIG 4 .
Brain cyst rigidity is dependent on the presence of ppGalNAc-T2 and -T3. BALB/cdm2−/− mice were infected with T. gondii strains as indicated in Materials and Methods. Three weeks postinfection, the brains of infected mice were harvested and homogenized with or without paraformaldehyde fixation to determine the fragility of brain cysts that developed in vivo. The difference between wild-type (WT) and ppGalNAc-Δt2 T. gondii as well as that between WT and ppGalNAc-Δt3 T. gondii was statistically significant (asterisks; one-way ANOVA and Dunnett post hoc test; P < 0.05), demonstrating that glycosylation is necessary for cyst stability. Wild-type T. gondii, black bars; ppGalNAc deletion T. gondii mutants, dark gray bars; ppGalNAc-complemented T. gondii strains, light gray bars.