Fig. 1. Cyclophosphamide disrupts gut mucosal integrity.

(A–B). Hematoxilin-eosin staining of the small intestine epithelium at 48h post-NaCl (Co) or CTX or doxorubicin (Doxo) therapy in C57BL/6 naïve mice (A). The numbers of inflammatory foci depicted/mm (B, left panel, indicated with arrowhead on A), thickness of the lamina propria reflecting edema (B, middle panel, indicated with # on A) and the reduced length of villi (B, right panel, indicated with arrowhead in A) were measured in 5 ilea on 100 villi/ileum from CTX or Doxo -treated mice. (C). A representative microphotograph of an ileal villus containing typical mucin-containing goblet cells is shown in vehicle- and CTX or Doxo-treated mice (left panels). The number of goblet cells/villus was enumerated in the right panel for both chemotherapy agents. (D). Specific staining of Paneth cells is shown in two representative immunofluorescence microphotographs (D, left panels). The quantification of Paneth cells was performed measuring the average area of the lysozyme-positive clusters in 6 ilea harvested from mice treated with NaCl (Co) or CTX at 24–48 hours. (E). Quantitative PCR (qPCR) analyses of Lysozyme M and RegIIIγ transcription levels in duodenum and ileum lamina propria cells from mice treated with CTX at 18 hours. Means±SEM of normalized deltaCT of 3–4 mice/group concatenated from three independent experiments. (F). In vivo intestinal permeability assays measuring 4 kDa fluorescein isothiocyanate (FITC)-dextran plasma accumulation at 18 hours post-CTX at two doses. Graph showing all data from four independent experiments, each dot representing one mouse (n=13–15). Data were analyzed with the t-test. *, p<0.05, **, p<0.01, ***, p<0.001.