Abstract: Objective To compare the effects of three different culture systems on the proliferation ability, surface marker and differentiation potential of bone marrow stromal stem cells (hBMSCs), and to explore a suitable expansion system for hBMSCs. Methods hBMSCs were obtained and cultured respectively in three culture systems: DMEM, DMEM+basic fibroblast growth factor (bFGF) and Mesenchymal Stem Cell Medium-animal component free (MSCM-acf), to the sixth generation of repeated passages. The cell yield of each culture system for each rate was counted. Cell surface markers of P4-P6 were detected using flow cytometry. At the same time, hBMSCs of P6 in each culture system were induced for chondrogenic differentiation, osteogenic differentiation and adipogenic differentiation. Results The cell yield in MSCM-acf group was far greater than that of the other two groups; The positive indicators of hBMSCs were detected by flow cytometry, in MSCM-acf group, CD73, CD90 and CD105 were all greater than 99%, the sum of negative cocktails was lower than 2%, which showed better results compared with the other two groups, especially DMEM+bFGF group. All of the three groups had the potential of differentiation. Cartilage differentiation in DMEM+bFGF was better. Adipogenic differentiation and osteogenic differentiation in MSCM-acf group were better than the other two expansion systems. Conclusion MSCM-acf expansion system can achieve a large number of hBMSCs amplification, and maintain the activity of cells. Therefore, MSCM-acf can be considered as an ideal hBMSCs expansion system.

Key words: Bone marrow stromal stem cells, Expansion system, Surface marker, Differentiative potential