Novel Source for Tooth Regeneration: Human induced Pluripotent Stem Cells derived Odontogenic Mesenchymal Stem Cells

Abstract Backgroud: Research on tooth regeneration using human-induced pluripotent stem cells (hiPSCs) is valuable for autologous dental recovery. Acquiring mesenchymal and epithelial cells as a resource for dental regeneration is necessary because mesenchyme-epithelium interactions play an essential role in dental development. However, the generation of dental mesenchyme from hiPSCs has not yet been reported. Objectives: This study attempts to establish hiPSC-derived mesenchymal stem cells (MSCs) with odontogenic potential. Since most dental MSCs are derived from the neural crest, hiPSCs were induced to differentiate into MSCs through neural crest formation to acquire the properties of dental MSCs. Methods: To differentiate into the neural crest, established human iPSCs were cultured and differentiated on PA6 stromal cells, and differentiated hiPSCs formed neurospheres on ultralow attachment plates. Neurospheres were cultured in serum-supplemented medium and differentiated into MSCs. The properties of neural crest-mediated MSCs (NC-MSCs) were verified by characterization of MSC markers and coculture with Hertwig's epithelial root sheath/epithelial cell rests of Malassez (HERS/ERM). Results: The results showed that NC-MSCs continuously expressed MSC markers for 15 passages. NC-MSCs and HERS/ERM cocultured under odontogenic induction conditions expressed odontogenic/osteogenic-related genes and DSPP proteins and yielded calcium deposits. Under in vivo conditions, NC-MSCs cocultured with HERS/ERM expressed DSPP proteins and formed dentin-like structures after 12 weeks. Conclusion: These results indicated that NC-MSCs established from hiPSCs are a novel cell source for dental recovery.