OBJECTIVE: To investigate the role of adult cardiomyocytes in the differentiation of mesenchymal stem cells (MSCs) into cardiomyocytes. METHODS: Rat MSCs were isolated by a Percoll's gradient solution and cultured in low-glucose Dulbecco' s modified Eagle' s medium (DMEM). After 2 passages, cell-surface antigen CD34, CD71 and CD90 for rat MSCs were determined by flow cytometry, and these MSCs were transfected with pEGFP-N3 by Lipofectamine2000. Then those MSCs labeled with GFP, were cultured in contacted, nocontacted and conditioned with adult rat myocardiocytes. Immunofluorescence staining against alpha-actin, desmin, and troponin-T were performed after 1 week. RESULTS: Immunofluorescence staining was positive against alpha-actin, desmin, and troponin-T on MSCs in contacted culture group. In contrast, no alpha-actin, desmin, and troponin-T expression on MSCs were observed in the noncontacted culture group and the conditioned culture group. CONCLUSION: Direct cell-to-cell contact between MSCs and adult cardiomyocytes may induce differentiation of MSCs into cardiomyocytes.
OBJECTIVE: To investigate the role of adult cardiomyocytes in the differentiation of mesenchymal stem cells (MSCs) into cardiomyocytes. METHODS:Rat MSCs were isolated by a Percoll's gradient solution and cultured in low-glucose Dulbecco' s modified Eagle' s medium (DMEM). After 2 passages, cell-surface antigen CD34, CD71 and CD90 for rat MSCs were determined by flow cytometry, and these MSCs were transfected with pEGFP-N3 by Lipofectamine2000. Then those MSCs labeled with GFP, were cultured in contacted, nocontacted and conditioned with adult rat myocardiocytes. Immunofluorescence staining against alpha-actin, desmin, and troponin-T were performed after 1 week. RESULTS: Immunofluorescence staining was positive against alpha-actin, desmin, and troponin-T on MSCs in contacted culture group. In contrast, no alpha-actin, desmin, and troponin-T expression on MSCs were observed in the noncontacted culture group and the conditioned culture group. CONCLUSION: Direct cell-to-cell contact between MSCs and adult cardiomyocytes may induce differentiation of MSCs into cardiomyocytes.