WIF1 and infection: To validate the efficacy and specificity of these Wnt membrane complex inhibitors at the concentrations used to characterize infection, DKK-1, WIF-1, and Dvl-PDZ II were used to treat 293T cells transfected with TF and stimulated with Wnt3A for 20 h (gray bars) or RVFV MP12 for 5 h (blue bars) (Fig. 5A).