To test which host cell signaling pathway was being used by atypical Toxoplasma strains to activate IRF3, we infected wild type, Unc93B1 3 d mutant (which are defective in intracellular TLR trafficking and activation) or MyD88 and TRIF double knockout immortalized macrophages with COUGAR and performed qPCR analysis for Rsad2 20 h post infection. Here, UNC93B1 is linked to infection.