FIG. 3.

Ex vivo killing and restriction of parasite replication by TNFR1/2^−/−macrophages. CPS-primed PECs from WT and TNFR1/2^−/− mice were infected with GFP-PTG ex vivo at an MOI of 0.5. (A) Infection rate expressed as a percentage of GFP-positive macrophages, as monitored by flow cytometry. (B) Kinetics of GFP-PTG replication expressed as intracellular parasite growth (number of tachyzoites per vacuole), determined by light microscopy at 0, 13, and 26 h postinfection. Over 400 macrophages from three individual mice per group were counted per time point. (C) Comparison of frequencies of CD154⁺ T cells, CD40⁺ macrophages, and IGTP⁺ macrophages for naïve mice (n = 2) and primed WT and TNFR1/2^−/− mice (n = 3). KO, knockout.