Gross morphological changes in the distal colon assessed in H&E stained cross sections.

<p>An intact epithelial lining and systematic arrangement of colonic layers were evident in sections from sham-treated animals at all time points <b>(A-A</b>^<b>II</b><b>)</b>. Immune infiltrate, flattening of the glands, disruption to the epithelial lining and destruction of mucosal epithelium, goblet cell loss and muscular edema were observed in colon tissues from TNBS-administered <b>(B-B</b>^<b>II</b><b>)</b> and UCM-treated <b>(E-E</b>^<b>II</b><b>)</b> guinea-pigs at all time points. Sections from MSC and CM-treated animals revealed initiation of colonic repair at 6 hours post induction of colitis <b>(C-D)</b>. Restoration of colonic architecture was observed at 24 <b>(C</b>^<b>I</b><b>-D</b>^<b>I</b><b>)</b> and 72 hours <b>(C</b>^<b>II</b><b>-D</b>^<b>II</b><b>)</b>. <i>n</i> = 4/group/time point. Scale bars = 50μm.