Osteogenic differentiation of bone marrow mesenchymal stem cells during in vitro culture

Objective:To observe the characteristic of in vitro culture and osteogenic differentiation of bone marrow mesenchymal stem cells(MSC).Methods:The human bone marrow MSCs were acquired through density gradient centrifugation,then expanded and cultured in vitro,and induced to differentiate into osteoblasts.The calcified nodules were determined by alizarin red staining(ARS),and the alkaline phosphatase(ALP)was detected by the calcium cobalt method.Results:The bone marrow MSCs actively proliferated from day 1to day 3,fused into monolayer cells after culture of 3to 5days.Then the gradual accumulation of cells and the precipitation of mineral salt formed mineral node with the extending culture and induction time.After incubation for 14and 21days,the formation ratesof mineral nodes reached(70.5 ±3.5)%and(87.5±3.5)%respectively,and the positive rates of ALP staining were(41.5±1.5)%and(85.2±1.7)%respectively.Conclusion:Under the in vitro culture condition,the bone marrow MSCs can be induced to differentiate into the ALP positive osteoblasts containing mineral nodes.