The Osteogenic Differentiation of Mesenchymal Stem Cells Derived From Dental Pulp in Modular Alginate-gelatin/nano-hydroxyapatite Microcapsules

Abstract Background Microcapsule is considered as a promising 3D microenvironment for Bone Tissue Engineering (BTE) applications. Microencapsulation of cells in an appropriate scaffold not only protects cells against excess stress but also promotes cell proliferation and differentiation. ResultsThe SEM results revealed that Alg/Gel microcapsules containing nHA showed a rough and more compact surface morphology in comparison with the Alg/Gel microcapsules. Moreover, microencapsulation by Alg/Gel/nHA could improve cell proliferation and induce osteogenic differentiation. The cells cultured in the Alg/Gel and Alg/Gel/nHA microcapsules after 21 days showed 1.4-fold and 1.7-fold more activity of BMP-2 gene expression in comparison with the cells cultured on the polystyrene surface as a control group. These amounts for the BMP-2 gene were 2.5-fold and 4-fold more expression for the Alg/Gel and Alg/Gel/nHA microcapsules after 28 days. The nHA addition to hDPSCs-laden Alg/Gel microcapsule could also up-regulate the bone-related gene expressions of osteocalcin, osteonectin, and RUNX-2 during 21 and 28 days culture period. Calcium deposition and ALP activities of the cells were observed in accordance with the proliferation results as well as the gene expression analysis. ConclusionThe study demonstrated that microencapsulation of hDPSCs inside Alg/Gel/nHA hydrogel can be a potential approach for regenerative dentistry in the near future.