Endoscopic Transplantation of Mesenchymal Stem Cell Sheets in Experimental Colitis in Rats.

Owing to the recent progress in regenerative medicine technology, clinical trials that harnessed the regeneration and immune modulation potentiality of stem cells for treating IBD have shown promising results. We investigated the feasibility and utility of intraluminal endoscopic transplantation of rat MSC sheets in murine models of experimental colitis for targeted delivery of stem cells to lesions. We isolated adipose-derived mesenchymal stem cells (AD-MSC) and bone marrow-derived mesenchymal stem cells (BM-MSC) from EGFP-transgenic rats and fabricated the cells in sheet forms using temperature-responsive culture dishes. The MSC sheets were endoscopically transplanted to the inflamed area in electrocoagulation and DNBS colitis model. The effect of the transplantation was verified using endoscopic scoring and histological analysis. In the electrocoagulation model, the AD-MSC group showed significantly decreased ulcer size in the transplanted regions. In the DNBS colitis model, the AD-MSC group showed decreased inflammation and colitis in the transplanted regions. Histologic analysis showed that the MSC sheets had successfully attached to the inflamed mucosa in both the electrocoagulation and DNBS colitis model. Our results show that endoscopic transplantation of MSC sheets could be a new effective mode of stem cell therapy for IBD treatment.