Dental Pulp Stem Cells: an Alternative Source of Mesenchymal Stem Cells with Potential Osteogenic Regenerative Capacities

Abstract Background: Bone innate ability to repair without scaring is surpassed by major bone damage. Current gold-standard strategies do not achieve a full recovery of the bone biomechanical properties. To bypass these limitations, tissue engineering techniques based on hybrid materials made up of osteoprogenitor cells, like mesenchymal stem cells (MSCs), and bioactive ceramic scaffolds, like calcium phosphate-based (CaPs), are promising. Biological properties of the MSCs, including osteogenic potential, are influenced by the tissue source. The aim of this study is to define the MSC source and construct (MSC and scaffold combination) most interesting for its clinical application in the context of bone regeneration. Methods: MSCs of 9 healthy donors were isolated from adipose tissue, bone marrow and dental pulp. MSCs were cultured both on plastic surface and on CaPs (hydroxyapatite and β-tricalcium phosphate) to compare their biological features: proliferation rate, osteogenic potential, cell viability and activity, ability to colonize the CaPs and ALP activity. Results: iTRAQ results generated the hypothesis that anatomical proximity to bone has a direct effect on MSC phenotype. On plastic, MSCs isolated from dental pulp (DPSCs) were the MSCs with the highest proliferation capacity and the greatest osteogenic potential. On both CaPs, DPSCs are the MSCs with the greatest capacity to colonize bioceramics. Furthermore, results show a trend for DPSCs are the MSCs with the most robust increase in the ALP activity. Conclusion: Based in our results, we propose DPSCs as a suitable MSCs for bone/dental regeneration cell-based strategies.