Figure 8. Impact of C. jejuni formic acid metabolism and perception on cytokine responses in “humanized” mice.

Hfa mice were generated as described (see methods) and orally infected with the C. jejuni wildtype strain (B2 WT), or with isogenic mutants deficient in the formate dehydrogenase subunit D (B2ΔfdhD) or the formic acid receptor (B2Δcj0952c). Secretion of (A) IL-6, (B) NO and (C) IFN-γ was determined in supernatants of ex vivo colon cultures obtained from infected (B2 WT: filled circles; B2ΔfdhD: grey circles; B2Δcj0952c: crossed circles) mice at d12 p.i.. Numbers of analyzed animals are given in parentheses. Means (black bars) and levels of significance (P-values) as compared to the respective groups (determined by Student's t-test) are indicated. Data shown are representative for three independent experiments.