Even though trace amounts of GRA3 mRNA were detected in ΔGRA3 cysts, the marked reduction of the cyst burden in the ΔGRA3-infected SCID mice after receiving CD8+ immune T cells indicates that GRA3 plays an important role in the capability of T. gondii cysts to persist in the presence of anti-cyst CD8+ immune T cells. Here, CD8A is linked to cyst.