Objective: The aim of the present study is to isolate and characterize human dental pulp stem cells (DPSCs).Surface markers expression utilizing surface markers for flow cytometry. The odontogenic differentiation of DPSCs was assessed.
Material and methods: dental pulp tissuses were collected from impacted third molars. samples were treated with collagenase before centrifugation to allow release of the cells. Cells were cultured in complete culture medium for 12-14 days. After reaching confluence, the isolated cells were characterized by flow cytometry using CD105 and CD45. The cells were induced for odontogenic differentiation by placing the cells in odontogenic induction media for 14 days. Odontogenic differentiation was evaluated by Alizarin Red stain and by the expressions of dentine sialo phospho protein (DSPP), dentin matrix protein-1 (DMP-1) and alkaline phosphatase (ALP) activity, which were assessed by RT-PCR.
Results: The results showed that successful isolation of stem cells from human dental pulp was achieved. Cells were successfully sub-cultured and expanded up to the third passage. A flow cytometric analysis was done after stem cells isolation. Isolated DPSCs were identified by positive expression of CD105 and negative expression of hematopoietic marker C. The results showed that differentiatiationed odontoblastic like cells from DPSCs induced by odontogenic medium were stained by Alizarin Red at days 7 and 14. RT-PCR results indicated that all cultured cells efficiently differentiate into dentin forming cells and expressed specific DSPP, DMP1 and ALP genes at days 7 and 14.
Conclusion: DPSCs can be a possible source of stable differentiated odontoblastic cells. Their ability of inducing hard tissue formation offer an alternative method to save teeth with compromised structural integrity.