Biological features of primarily cultured marrow stromal cells and marrow mesenchymal stem cells of monkey

AIM: To culture primarily marrow stromal cells and marrow mesenchymal cells of monkey and to make a comparative study on the difference between the two kinds of cells in morphology and growth. METHODS: The adherent cells were selected as marrow stromal cells when marrow suspension were cultured. Marrow mesenchymal stem cells were isolated from marrow suspension by discontinuous gradient centrifugation on percoll (mass concentration: 1073 g·L -1 ). The two kinds of cells were primarily cultured on the DMEM medium containing 100 mL·L -1 fetal boving serum. RESULTS: The cultured marrow stromal cells proliferated into uniform fibroblast like cells rapidly. Cells from the stromal cells grew confluent 1 wk later and calcification nodes formed 3 wk later. The marrow mesenchymal stem cells slowly grew into cells with many kinds of morphotype. Some mesenchymal stem cells survived without significant proliferation during the 4 week culture. Some of these cells were round and unspread, whereas some cells were lamellar and well spread. Neurocyte like cells could be found when the marrow mesenchymal stem cells were cultured, though the number of them was very small. There were also some cells from mesenchymal stem cells which had significant proliferation 2 wk after the primary culture. They grew into cell polarity which looked like a clone or a band. CONCLUSION: The proliferation and differentiation of the marrow stromal cells and the marrow mesenchymal stem cells were different during the primary culture under non induction condition. Cells from the marrow stromal cells were homomorphic and could differentiate into osteoblast like cells without induction. And the potential of multi differentiation showed that mesenchymal stem cells grew into heteromorphic cells without induction during the primary culture .