Figure 4

Histological analysis of the distal colon on day 7 of control mice (no dextran sulfate sodium (DSS)), umbilical cord mesenchymal stem cell-treated mice, DSS + phosphate-buffered saline-treated mice and DSS + umbilical cord mesenchymal stem cell-treated mice. Hematoxylin and eosin (H&E) staining showed improvement after umbilical cord mesenchymal stem cell (UCMSCs) treatment because it reduced the extent of the inflamed area, crypt damage, edema of submucosa and infiltration of inflammatory cells. Periodic acid–Schiff (PAS) staining detected goblet cells that displayed a strong purple/magenta color when stained with PAS reagent. There was complete depletion of goblet cells in the crypts of the dextran sulfate sodium (DSS) + phosphate-buffered saline mice. In contrast, DSS + UCMSCs mice showed retention of some goblet cells. Masson’s trichrome staining showed increased deposition of collagen after DSS treatment (blue/green-stained areas represent collagen deposits).