Figure 7. Il18r1^−/− mice are highly susceptible to infection with T. cruzi and display lower frequency and absolute numbers of Th1 cells.

(A) Parasitemia curve, (B) survival and (C) parasite load in the myocardium at day 14 pi of Il18r1^−/−, Myd88^−/− and WT B6 mice infected with 2 × 10³ blood trypomastigotes of the Y strain. Survival curves are statistically different (p<0.05). (D–I) Mean frequencies and absolute numbers of (D, G) IFN-γ⁺CD4⁺(E, H) IFN-γ⁺CD8⁺ and (F, I) GzB⁺CD8⁺ cells, gated on CD4⁺ or CD8⁺ T splenocytes from 4 to 8 individually analyzed mice at day 14 pi. Data are representative of 3 independent experiments. Error bars = SEM; ns = non significant; *p≤0.05; **p≤0.01; ****p≤0.0001 (two-tailed Student t-test).