Formation of Tooth Crown Using Epithelial and Mesenchymal Stem Cells

Objective: The study was determined to assess the ability of combination of adult dental epithelial and mesenchymal stem cells to regenerate tooth crown. Methods: Proven to be in existence previously, the dental epithelial stem cells in apical bud(ABSCs) and dental pulp stem cells(DPSCs) in adult rodent incisors were isolated and co-cultured. Von Kossa staining, alkaline phosphatase(ALP) activity, immunocytochemical and RT-PCR analyses were used to investigate the influence of epithelial inductive signals on DPSCs. ABSCs and DPSCs pellets were loaded into one piece of prefabricated absorbable gelatin sponges to build recombined DPSC-ABC explants for 2-week subrenal incubation, followed by morphologic observation. Result: Co-cultured DPSC-ABCs in vitro showed active odontogenic differentiation ability as indicated by the accelerated matrix mineralization, up-regulated ALP activity, cell cycle modification and expression of tooth-specific proteins and genes. Recombined DPSC-ABC pellets formed typical tooth-shaped tissues with balanced amelogenesis and dentinogenesis in vivo. Conclusions: The recombination of dental epithelial and mesenchymal stem cells in adult tissue can reexhibit tooth crown formation, thus implying a practical way of regenerating biological tooth utilizing available cell sources.