(a) WT, Myd88−/−, and mice with cell type-specific inactivation of MyD88 in DCs, epithelial cells (E), macrophages (M), T cells (T), DCs and epithelial cells (DC&E), DCs and macrophages (DC&M), and DCs and T cells (DC&T) were infected orally with 20 cysts per mouse of the ME49 strain of T. gondii. Mesenteric lymph nodes (mLNs) were harvested on day 7 post-infection, and IFN-γ production by CD4+ T cells was analyzed by flow cytometry. The data shown are representative of five independent experiments each involving 4–6 mice per group. (b) Average frequency and (c) absolute quantification of TH1 cells (CD4+IFN-γ+) in the mLNs of mice infected orally with the parasite. The data shown are representative of five independent experiments each involving 4–6 mice per group. * P< 0.01; ** P< 0.001.