Figure 5.

Apoptotic and proliferating epithelial cell as well as immune cell responses in the ileum and colon following peroral MDR P. aeruginosa challenge of mice with a human gut microbiota suffering from subacute ileitis. At day 5 following subacute ileitis induction, mice with a human gut microbiota were either perorally challenged with MDR P. aeruginosa (+Psae, dissolved in PBS) or with PBS alone (Mock). Uninfected mice with a human gut microbiota but without ileitis served as control animals (Naive). 96 h following Psae challenge, the average numbers of apoptotic (Casp3+; A,E) and proliferating (Ki67+; B,F) epithelial cells as well as of T lymphocytes (CD3+; C,G), and regulatory T cells (FOXP3+; D,H) in at least six high power fields (HPF) were quantitatively assessed in ileal (A–D) and colonic (E–H) paraffin sections applying in situ immunhistochemistry. Box plots represent the 75th and 25th percentiles of the median (black bar inside the boxes). The total range and significance levels determined by one-way ANOVA test followed by Tukey post-correction test for multiple comparisons are shown. The total numbers of analyzed animals are given in parentheses. Data were pooled from four independent experiments.