Abstract: Objective To find the seed cells for replacing bone marrow mesenchymal stem cells(BMSCs) to treat bone defects by compared the capacity of osteogenesis from the BMSCs、human umbilical cord mesenchymal stem cells(UC-MSCs) and human placental mesenchymal stem cells(P-MSCs). Methods The Three MSCs were cultured in DMEM/Ham’sF-12 medium containing 10% fetal bovine serum, cell proliferation curve was drawn by CCK8 detected, and the cell surface antigens were measured using flow cytometry. Osteogenic ability was confirmed by the alkaline phosphatase(ALP) staining, alizarin red staining. To further explore the difference in organic components, their underlying genotypes and proteins, including RUNX2, ALP and osteocalcin(OCN), were analyzed by RT-qPCR and Western blot. Results Cell growth curve analysis indicated that three MSCs were in the exponential stage at 3 days following incubation. Flow cytometry analysis showed that more than 98% cells were positive for CD44, CD90 and CD105. ALP and Alizarin red staining displayed that three MSCs presented good mineralizationg ability by osteogenesis induced medium. RT-qPCR and Western blot showed that the three MSCs experiment group higher expression levels of osteogenic markers including RUNX2, ALP and OCN during the initial 9 and 18 days when compared with control(P<0.05). Conclusions The results exhibited that UC-MSCs and P-MSCs have good osteogenic ability, which expected to be as bone tissue engineering seed cells for the treatment of bone defects.

Key words: Bone marrow mesenchymal stem cells, Human umbilical cord mesenchymal stem cells, Human placental mesenchymal stem cells, Bone tissue engineering, Osteogenic differentiation