Title: 3408 - A Comparative Analysis of the Osteogenic Differentiation Potential of Intra-subject Dental Mesenchymal Stem Cells
Lewis Winning (Presenter)
Queen's University Belfast
Ikhlas El Karim, Queen's University Belfast
Gerard Linden, Queen's University Belfast
Chris Irwin, Queen's University Belfast
Fionnuala Lundy, Queen's University Belfast
The aim of this study was to compare the in-vitro osteogenic differentiation potential of within-subject mesenchymal stem cells (MSCs) derived from the dental pulp of permanent teeth (dental pulp stem cells – DPSCs), the dental pulp of deciduous teeth (pulp of human exfoliated deciduous teeth - SHEDs), and the periodontal ligament (periodontal ligament stem cells – PDLSCs).
Subjects were identified that required concurrent removal of both deciduous and permanent teeth for orthodontic purposes. Primary, mixed population cells from dental pulp, deciduous dental pulp, and periodontal ligament were obtained by the tissue out-growth method. Isolation of Stro-1 +ve cells from the primary cell cultures was achieved by immunomagnetic separation. Cultures were analysed for stem cell markers using flow cytometry. Cells were induced with an osteogenic cocktail of 5mM β-glycerophosphate, 100nM dexamethasone and 50 mg/mL–1 ascorbic acid for up to 21 days. Osteogenic responses were assessed functionally by an alkaline phosphatase (ALP) activity assay and an alizarin red staining assay. Expression of the early osteogenic associated genes ALPL, RUNX2, COL1A1, SPP1 (normalised to the house keeping genes GUSB, and B2M) were compared by qPCR at days 1, 4 and 7 of differentiation.
Functional analysis revealed there were significant differences in intracellular ALP on days 7, 10 & 14 with PDLSCs > SHEDs > DPSCs. Quantification of alizarin red staining, showed significantly more mineralisation for PDLSCs by day 21. Gene expression analysis showed significant early up-regulations of the osteogenic markers ALPL and COL1A1 for PDLSCs over DPSCs and SHEDs. SHEDs showed significantly higher up regulation of ALPL over DPSCs.
Conclusions: PDLSCs showed a significantly higher osteogenic differentiation potential than both DPSCs and SHEDs evidenced by functional studies and gene expression. This may be of significance for the use of dentally derived MSCs in bone tissue engineering applications.
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE