RGD-Modified Alginate Scaffold Supplemented with BMP2 Supports Osteogenic Differentiation of Periodontal Ligament Derived Stem Cells (PDLSCs)

Nova Southeastern University, Davie, Florida, USA

Objective: To develop in vitro injectable cell-growth factor-scaffold system and to assess osteogenic differentiation of (PDLSCs). Background: Multipotent stem cells derived from human periodontal ligament stem cells (PDLSCs) are able to promote the formation of bone tissue making this cells interesting candidate for craniofacial bone tissue engineering. RGD-coupled alginate is considered as promising scaffold for the capacity to mimic many functions of the extracellular matrices. Bone Morphogenic Protein-2 (BMP-2) is a potent growth factor, plays an essential role in osteogenic induction. Our hypothesis is that, the combination of BMP-2 to cells embedded within alginate beads scaffold, accelerates the osteogenic differentiation. Methods: Human PDLSCs was isolated and cultured using standard culture conditions. The cells were encapsulated in the alginate gels and their proliferation was measured. The PDLSCs in alginate beads were supplemented with 50, 100, and 200ng/ml of BMP-2. The activity of alkaline phosphatase was measured through a pNPP assay. The osteogenic differentiation of ALP, RUNX2 and COL1 gene expression was measured using quantitative PCR. Results: The WST demonstrated that PDLSCs were viable at all concentrations. Furthermore, the cells were viable until day7. The quantitative PCR results reported upregulation expressions in the ALP, and COL1 genes at all BMP2 concentrations with peak at 200ng/ml. Conclusions: BMP2 enhances the osteogenic differentiation. RGD modified alginate- BMP2- PDLSCs- system represents a promising source for bone tissue engineering. Grants: This study was funded by Florida Blue foundation grant # 333248.