Sutures are fibrous joints between two or more cranial and/or facial bones that enable longitudinal growth of the craniofacial complex. Premature osseous fusion of sutures will cause craniofacial anomalies named craniosynostosis. With an ultimate goal to engineer a viable cranial suture for craniosynostosis treatment, it is a prerequisite to characterize the cell phenotype of normal development suture and its associated dura. Objective: the present study is to elucidate cell phenotypes within the suture-dura complex. Our hypothesis is that the dura mater and its associated suture comprise a subpopulation of mesenchymal cells with multiple differentiation potentials. Methods: Cranial suture and its associated dura mater were sterilely removed from neonatal rats' skulls. The dissected tissue was finely minced, washed and digested with collagenase type I. The harvested cells were then plated at a density of 10^6 cells/per 100-mm petri dishes and cultured in basic or differentiation (osteogenic, adipogenic, and chondrogenic) medium respectively. At defined time points specific cell lineage markers were assessed by biochemical and molecular biological techniques. Results: cranial suture and its associated dura mater-derived cells comprise a subpopulation of mesenchymal cells with osteogenic (alkaline phophastase, osteocalcin, calcium, osteopontin), adipogenesis (PPAR-gamma2) and chondrogenesis (aggregan, collagen type II). Conclusion: The present study is the first report to reveal multipotent cells exist in develping cranial suture complex.
Supported by Whitaker Foundation, March of Dimes, Cleft Palate Foundation and Orthodontic Department of UIC.