Bioengineered Teeth from Cultured Ectomesenchymal Stem Cells

Objectives:The aim of the present study was to evaluate the role of ectomesenchymal stem cells (EMSCs) in producing of a bioengineering tooth recombining with odontogenic epithelium. Methods: The biological behaviors of EMSCs, isolated from the first branchial arch of E12.5 SD rats, including growth proliferation characteristics, cell phenotype, differentiation abilities in vivo and in vitro were analyzed. The odontogenic ability of EMSC was investigated in a two and three dimensional culture system respectively in the presence of bFGF, IGF-1 or TGF-â1 and tooth germ cell conditioned medium (TGC-CM). The induced EMSCs were covered with dental epithelium from E12.5 SD rats to form recombinant explants and implanted subcutaneously into nude mice. 14~18 wks later, implants were excised for histological and immunohistochemical analyses. Results: The morphological and biological characteristics of EMSCs were similar to that of the other adult stem cells, like BMSCs. The results indicate that EMSCs are capable of responding to show some characteristics of odontoblast-like cells. Histological analysis revealed that tooth-like structures including enamel-like tissue and dentin-pulp complex were generated within implants of experimental groups but not of control groups. Immunohistochemical analysis of implants demonstrated that ameloblastin was expressed in newly-formed enamel-like tissues and DSP was expressed in dentin-like tissues. It was demonstrated that EMSC could be induced into functional differentiated odontoblast-like cell. Conclusions: EMSC might be the original cells of forming the most of the adult stem cells remaining in the orofacial region. the results of above work indicated that it is possible to induce an odontogenesis and engineer a tooth using EMSC recombining with dental epithelial cells. EMSC is proved to be a competent tooth forming cells, and the cells derived from EMSC, besides the DPSC, could be a potential candidate cells for engineering of tooth. Acknowledgement: This work was supported by NSFC (30572046).