SHED repair critical-size calvarial defects in mice

OBJECTIVE: Stem cells from human exfoliated deciduous teeth (SHED) are a population of highly proliferative postnatal stem cells capable of differentiating into odontoblasts, adipocytes, neural cells, and osteo-inductive cells. To examine whether SHED-mediated bone regeneration can be utilized for therapeutic purposes, we used SHED to repair critical-size calvarial defects in immunocompromised mice. MATERIALS AND METHODS: We generated calvarial defects and transplanted SHED with hydroxyapatite/tricalcium phosphate as a carrier into the defect areas. RESULTS: SHED were able to repair the defects with substantial bone formation. Interestingly, SHED-mediated osteogenesis failed to recruit hematopoietic marrow elements that are commonly seen in bone marrow mesenchymal stem cell-generated bone. Furthermore, SHED were found to co-express mesenchymal stem cell marker, CC9/MUC18/CD146, with an array of growth factor receptors such as transforming growth factor beta receptor I and II, fibroblast growth factor receptor I and III, and vascular endothelial growth factor receptor I, implying their comprehensive differentiation potential. CONCLUSIONS: Our data indicate that SHED, derived from neural crest cells, may select unique mechanisms to exert osteogenesis. SHED might be a suitable resource for orofacial bone regeneration.