Potential Characteristics of Stem Cells from Human Exfoliated Deciduous Teeth Compared with Bone Marrow-derived Mesenchymal Stem Cells for Mineralized Tissue-forming Cell Biology

Introduction: Tissue engineering and regenerative medicine using stem cell biology has been a promising field for treatment of local and systemic intractable diseases. Recently, stem cells from human exfoliated deciduous teeth (SHED) have been identified as a novel population of stem cells. This study focused on the characterization of SHED as compared with bone marrow derived mesenchymal stem cells (BMMSCs). Methods: We investigated potential characteristics of SHED by using DNA microarray, real-time reverse transcriptase polymerase chain reaction, and immunofluorescence analysis. Results: Multiple gene expression profiles indicated that the expression of 2753 genes in SHED had changed by >= 2.0-fold as compared with that in BMMSCs. One of the most significant pathways that accelerated in SHED was that of bone morphogenetic protein (BMP) receptor signaling, which contains several cascades such as PKA, JNK, and ASK1. When the BMP signaling pathway was stimulated by BMP-2, the expression of BMP-2, BMP-4, Runx2, and DSPP was up-regulated significantly in SHED than that in BMMSCs. Furthermore, the BMP-4 protein was expressed much higher in SHED but not in BMMSCs, as confirmed by immunofluorescence. Conclusions: By using the gene expression profiles, this study indicates that SHED is involved in the BMP signaling pathway and suggests that BM P-4 might play a crucial role in this. These results might be useful for effective cell-based tissue regeneration, including that of bone, pulp, and dentin, by applying the characteristics of SHED. (J Endod 2011;37:1647-1652)