Migration of Mesenchymal Stem Cells of Bursal Tissue after Rotator Cuff Repair in Rats.

Purpose  The purpose of this study is to verify migration of mesenchymal stem cells of bursal tissue into the healing site after rotator cuff repair in rats. Methods  Fischer rats and green fluorescent protein (GFP)-transgenic rats were used. Bursal tissue from GFP rats was isolated and transplanted into tendon repair sites in Fischer rats. We examined the histology of the rotator cuff and the proportion of GFP-positive cells in the repaired rotator cuff 1, 3, and 6 weeks after surgery. Results  Cell migration was observed during the third and sixth week after surgery. We also found mesenchymal stem cells and formed bursal cluster patterns in the repaired rotator cuff tendons. Conclusion  Mesenchymal stem cells migrated from bursal tissue and infiltrated the repaired rotator cuff tendons. Clinical Relevance  Mesenchymal stem cells from bursal tissue can contribute to the healing progress of the repaired rotator cuff.