Figure 6. Trem1^−/− mice develop smaller inflammatory lesions and show decreased cellular infiltrates at L. major infection sites.

(A) Trem1^+/+ and Trem1^−/− mice were inoculated with 3×10⁶ L. major promastigotes s.c. in the footpad and lesion development was measured over time. Each data point represents the mean lesion size ± SEM of n = 5 mice analysed per group. (B) Parasite load was assessed at 35 days post infection (p.i.) by limiting dilution analysis. (C) Infected footpads from Trem1^+/+ and Trem1^−/− mice (n = 4–5 mice per group) were isolated 21 days p.i., digested and the cellular content was analysed by flow-cytometry. Data show mean values ± SEM and are representative of two independent experiments. (D) Draining lymph node cells from Trem1^+/+ and Trem1^−/− mice (n = 4 mice per group) were isolated 35 days p.i.; the frequency of CD4⁺ IFNγ⁺ T cells was analysed by intracellular FACS staining or cells were re-stimulated with UV-treated L. major parasites and IFNγ levels in the supernatants were assessed by ELISA. Data show mean values ± SEM of triplicate measurements. Representative data from one out of three independent experiments are shown. ***, p<0.001; **, p<0.01; *, p<0.05.