Five days after infection with 106 RH-Δompdc tachyzoites, the parasites in mice peritoneal fluids were almost eliminated, and the levels of IL-12 and IFN-γ had accordingly decreased, which indicated that the effect of a one-time treatment to the 4T1 tumor with RH-Δompdc may be not enough. The gene discussed is IFNG; the disease is neoplasm.