Nanoscale Microscopic Analysis Human Dental Stem Cells on Biopolymer Surfaces

Tissue engineering approaches rely on the widespread use of biodegradable biopolymer scaffolds for cell delivery and transplantation. We are investigating the use of dental stem cell (DSC) seeded polyester scaffolds to regenerate biological tooth substitutes for treatment of partial or total tooth loss. Our published reports demonstrate the validity of this technique using cultured rat tooth bud cells (Duailibi et al., 2004; Duailibi et al.,2006). Here we characterize the interactions of human DSCs with biodegradable PGA/PLGA scaffolds with atomic force microscopy (AFM), specifically using the tapping mode (intermittent contact mode) by NanoScope IIIA (Veeco, USA), to identify surface characteristics and cellular response. Objective: To characterize the hDSC – PGA biopolymer surface interface at the nanoscale level. Methods: hDSCs were obtained from patients scheduled for routine third molar extraction, in accordance approved protocols (CONEP-13083). Isolated human tooth cells were plated at 2.5 x 105cells/ml, and expanded in standard tissue culture conditions. At confluence, cultured hDSCs were harvested by trypsinization, split into equal portions, and statically seeded onto PGA scaffolds with and without Collagen coating for 12 hr prior to analysis using AFM and low vacuum scanning electron microscopy. Results: Both types of microscopic analyses revealed lack of hDSC adhesion on biopolymer scaffolds without collagen treatment. Conclusion: Our nanomicroscopic analyses reveal the importance of collagen coating of biopolymer scaffolds for tooth tissues engineering strategies, to facilitate hDSC adhesion. These studies were supported by the University Federal São Paulo, São Paulo Brazil, CNPq,FAPESP 07/51227-4, Tufts University, Boston, MA, The Center for the Integration of Medicine and Innovative Technology (CIMIT), and NIH/NIDCR grants TW007665 and DE016132 (PCY).