Culture, identification of phenotype,and labeling of mesenchymal stem cells in vitro in SD rats

Objective To investigate the methods of isolation,culture,identification and labeling of mesenchymal stem cells(MSCs) in vitro and lay a foundation for further study on intervention of MSCs on immunologic rejection of organ transplantation. Methods MSCs were isolated and cultivated by adherent methods . The expressions of CD90 and CD45 of cells were analyzed by using flow cytometry in order to identify MSCs.The third generation of MSCs were labeled by DAPI,the labeling efficiency was detected.Results Primary cultured MSCs adhered to plastic surface within 48 h and reached 90% confluence within 7-10 d .Flow cytometry showed that the positive rates of CD90 and CD45 of MSCs at third generation were 99.8% and 6.8%. MSCs expressed CD90 but no CD45.All of the MSCs after labeling by DAPI showed blue fluorescence by immunofluoroscope. DAPI labeling was sensitive and highly efficient to MSCs.Conclusion Adherent method is simple and easy to isolate and cultivate MSCs and it can serve as a routine method.DAPI labeling can be used as a efficient method to label MSCs.