The biological characteristics of SD rat bone marrow-derived mesenchymal stem cells isolated and cultured with attachment method

objective To establish a simple and effective method of isolation,purification and cultivation of SD rat bone marrow-derived mesenchymal stem cells(MSCs) in vitro,and explore their biological characteristics.Methods MSCs were isolated and purified for culture in vitro and serial passage by the attachment culture method.The morphological changes of the MSCs were continuously observed under the inverted microscope.The cell growth curve was measured by MTT method, and membrane antigens were detected with flow cytometry(FCM).Results The MSCs in primary culture which were adhered to plastic surface within 48 h after displacement took the oval,asteroid,short and fusiform shapes.7 to 12 days after culture in DMEM medium containing 10%FBS,the cells reached 90%confluence in single layers,taking a long and fusiform shape.Further purification was achieved by expansion at serial passages.MSCs were in latency for 2 days, converted into growth period on the 3rd day and entered the stationary phase on the 5th day.FCM results indicated that the positive rate of CD45,CD90 and CD29 was 1.50%,99.18%,97.70%,respectively.Conclusions The attachment culture method can be effectively used to isolate and purify SD rat MSCs.The cultured MSCs are stable in growth with active proliferation and share the general biological characteristics of MSCs,which will further make them ideal seed cells for tissue engineering.