Inflammatory and immune cell responses following <i>C. jejuni</i> infection of infant mice.

<p>Conventionally colonized 3-weeks-old infant mice were orally infected with <i>C. jejuni</i> strain ATCC 43431 (crossed circles) or B2 (solid circles) as described in Methods. The average numbers of apoptotic cells (positive for caspase-3, panel <b>A</b>), neutrophilic granulocytes (neutrophils, positive for MPO-7, panel <b>B</b>), macrophages (positive for F4/80, panel <b>C</b>), T-lymphocytes (positive for CD3, panel <b>D</b>), regulatory T-cells (Tregs, positive for FOXP3, panel <b>E</b>) and B-lymphocytes (positive for B220, panel <b>F</b>) from at least six high power fields (HPF, ×400 magnification) per animal were determined microscopically in immunohistochemically stained colon sections at day 6 p.i. Uninfected mice (Naïve, open circles) served as negative controls. Numbers of analyzed animals are given in parentheses. Means (black bars) and levels of significance (<i>P</i>-values) determined by the Student’s <i>t</i>-test are indicated. Data shown are representative for three independent experiments.