Once we were able to obtain pure, high avidity IgY anti-STAg antibodies, we aimed to verify potential applications of those antibodies in T. gondii model. The standardized immunohistochemical assay using IgY anti-STAg antibodies was able to detect antigenic distinct structures in brain tissue sections, as follows: (i) parasitophorous vacuoles, demonstrated as rounded and compartmentalized structures (Figs. 3A and 3B); (ii) tissue cysts, represented by a wall bright fluorescence (Figs. 3C and 3D); and (iii) free tachyzoites (Fig. 3C) .