Therapeutic effect of bone marrow-derived mesenchymal stem cells on injured lung of rats

AIM: To investigate the therapeutic effect of bone marrow-derived mesenchymal stem cells (MSCs) on injured lung of rats. METHODS: MSCs were isolated from SD rats and injected into recipient rats after labeled with 4′-6-Diamidino-2-phenylindole (DAPI). The recipient rats were divided into 4 groups: lung injury group, MSCs treatment group, MSCs control group and normal control group. Lung tissue and bronchoalveolar lavage fluid (BALF) were collected 2 weeks after implantation. Cells which were labeled with DAPI and pan-cytokeratin positive were detected under fluorescence microscope. Lung structure, fibroblasts in interstitium were observed. The contents of hydroxyproline in lung and laminin, hyaluronan in BALF were detected. RESULTS: MSCs from donor could be found in injured lung of recipient rats and some of them were found pan-cytokeratin positive. The thickness of alveolar wall and the number of fibroblast in lung interstitium were reduced significantly in MSCs treatment group. MSCs engraftment could also reduce the contents of laminin and hyaluronan in BALF and hydroxyproline in injured lung (P0.01). CONCLUSION: MSCs could differentiate into alveolar epithelial cells in injured lung induced by bleomycin and ameliorate lung injury and fibrosis.