Comparison of phenotype and differentiation marker gene expression profiles in human dental pulp and bone marrow mesenchymal stem cells

OBJECTIVE: Bone marrow (BM) is the most utilized and well-studied source of stem cells. Stem cells from dental tissues have provided an alternate source of mesenchymal stem cells (MSCs). Dental pulp stem cells (DPSCs) have been shown to share a similar pattern of protein expression with BMMSCs in vitro. However, differences have been noted between DPSCs and BMMSCs. This study focuses on variation in expression of stem cell and differentiation markers between DPSCs and BMMSCs. MATERIALS AND METHODS: The two stem cells were isolated and compared for clonogenic potential, growth characteristics, multipotency, and stem cell marker expression. Specifically, the fatty acid binding protein 4, perilipin, alkaline phosphatase and osteonectic gene expression was analyzed by real-time polymerase chain reaction to confirm the capacity for adipogenic and osteogenic differentiation. RESULTS: MSCs from these cell sources were similar in their morphology and immune phenotype except for the expression of CD105. Growth curves and colony formation assay revealed proliferation rate of DPSCs was significantly faster than BMMSCs (P < 0.05). DPSCs appeared less able to differentiate into adipogenic lineage, although more able to differentiate into osteogenic lineage. CONCLUSION: Data from the present study indicate how DPSCs are different from BMMSCs though they are a population of MSCs. DPSCs are a novel population of MSCs as observed by their unique expression of differentiation and lineage specific genes. Further microarray analysis could be used to determine, which genes are differentially regulated in BMMSCs and DPSCs to establish uniqueness of each population of MSCs.