IFNG and infection: To resolve the extent to which the fetal hematopoietic response to maternal T. gondii infection was driven by IFNγ, the primary cytokine mediating immune clearance in T. gondii infection (Suzuki et al, 1988), we compared fetal hematopoiesis after prenatal exposure to both IFNγ and infection with two strains of T. gondii of increasing virulence.