Th1-type cytokines, gamma interferon (IFN-γ) especially[12], secreted from CD4+ Th1 cells can subsequently activate CD8+ Tc cells to turn into major cytotoxic effector cells for lysing tachyzoite-infected cells, limiting parasite dissemination during the phase of acute infection[11] as well as inhibiting cyst formation during chronic infection[7]. Here, IFNG is linked to cyst.