Isolation and Differentiation of Dental Pulp Stem Cells into Odontoblastic Lineage

Limited resources for adult stem cells necessitate appropriate methods for isolation, proliferation and differentiation of these cells. Human third molar is an easily available source in this regard that usually remains unused. The aim of this study was to investigate the isolation, culture and odontogenic differentiation of human dental pulp stem cells. In this experimental study, twenty human third molars were used for stem cell isolation. The digested pulp tissue culture approach was used to isolate stem cells. Some markers of stem cells were studied by RT-PCR. Stem cells were then induced towards odontoblast cells by use of BMP-2 and Dexamethasone. Expression of odontoblastic markers was investigated in induced cells by RT-PCR and immunocytochemistry methods. The human dental pulp stem cells were isolated with high efficiency. RT-PCR analysis showed that these cells express some markers of embryonic stem cells. However, the induced cells did not expressed odontoblastic markers such as DSPP, DMP-1, BMP7 and Osteopontin. Also the induced cells did not produce DSPP and DMP-1 proteins. Despite the successful isolation of stem cells, the induced cells failed to differentiate into odontoblasts. This may be due to the differentiation method as well as the passage during induction or monolayer culture.