Cerebral histopathological changes following acute ileitis induction. C57BL/6 wildtype (WT; black circles) and TLR-9 deficient (TLR-9-/-; white circles) mice were perorally infected with 100 cysts of T. gondii ME49 strain on day 0 to induce acute ileitis. Naïve mice served as negative controls (N). Intracerebral (A) IFN-γ, (B) TNF-α, and (C) IL-6 mRNA expression levels were measured in ex vivo brain biopsies applying quantitative RT-PCR. Numbers of analyzed mice (in parentheses), means (black bars), and levels of significance (P-values) determined by Mann–Whitney-U test are indicated. Data shown were pooled from three independent experiments.