Mesenchymal Stem Cell Therapy Stimulates Endogenous Host Progenitor Cells to Improve Colonic Epithelial Regeneration
Figure 8
Iterative injection of MSC on established radiation-induced colic ulcer increases the ability of epithelial cells to proliferate.
This effect is associated with an increase in SOX9 positive cells and a boosted WNT4 molecule expression by epithelial cells. (A) Representative pictures of PCNA immunostaining (blue staining) 8 weeks after irradiation and quantification of PCNA-positive cells per total number of crypt cells. Original magnification, x600. Irradiation reduces the proliferative ability of epithelial cells while the proliferative process is maintained at a basal level after MSC treatment. (B) Representative SOX9 immunostaining 8 weeks after irradiation. Irradiation drastically reduces the number of SOX9-high cells that are restored after MSC treatment. (C) Representative pictures of WNT4 immunostaining in colonic mucosa and quantification of the number of WNT4 expressing epithelial cells per crypt. Eight weeks after irradiation, WNT4 expression was not different from controls in all analyzed rats, while WNT4 expression in colonic mucosa of MSC treated rats was higher than in the control group. All analyses were performed on tissues located inside the irradiated field. In all experiments n = 6 for each group. Results were compared between groups by one-way ANOVA followed by a Tukey test. *p<0.001 versus control groups. Original magnification, x800.