Figure 3. Defective early trypanosomacidal mechanism in TLR4-deficient macrophages.

(A) Resident macrophages from C3H/HePas (wt) and C3H/HeJ (Tlr4^d/d) mice were infected with blood form trypomastigotes of the Y strain in the presence of L-NMMA (1 mM) and/or DFO (100 µM), according to the legend and as detailed in the Materials and Methods section. After 4 h of culture, cells were fixed and stained with Giemsa. Asterisk (*) indicates that the percentage of infected MO is significantly different (p<0.05) between WT and TLR4-deficient cultures without treatment. (B) Resident peritoneal macrophages from B6 and Tlr4^−/− mice were infected with blood form trypomastigotes of the Y strain, as described in Fig. 1, with (closed symbols) or without (open symbols) L-NMMA (1 mM). The number of trypomastigotes released into the supernatants was assessed daily from day 5 on. Each data point is expressed as the mean ± SEM of triplicates and experiments shown are representative of at least two independent ones.