Dental Pulp Derived Stem Cells: Optimizing Collection and Cryopreservation

DESCRIPTION (provided by applicant): The overall goal of this application is to develop an understanding of the collection, processing and cryobiological characteristics of stem/progenitor cells recovered from extracted teeth with the ultimate culmination of these data to allow for a cryobank of Dental pulp derived stem cells (DPSCs) for research and/or potential transplant or other clinical utilization as a human cell product processed under current good tissue practice (cGTP) as described under 21 CFR 127 1. Recent studies investigating this exciting source of post-natal stem cells have identified a population of clonogenic and highly proliferative cells derived from enzymatically digested Dental pulp tissue (Gronthos, et al., 2000). Results from these stud ies have indicated that these cells may have the potential to be utilized in stem cell mediated therapies and tissue engineering applications (Seo, et al., 2005). To allow further study and potential therapeutic use of these cells, investigators have just begun to evaluate the ability of these cells and their respective tissues of origin to survive cryopreservation processing. Ideally, the optimum cryopreservation process will be straight forward and effective when applied to the tissue as a whole, with the idea that stem cells could be extracted post-thaw. The rationale for this would be to preserve clinical samples for subsequent stem cell recovery as it is reasonable to speculate that cryopreservation of tissues in the clinic will be more practical than d irect primary isolation of stem cells, which would require additional equipment and personnel (Seo et al., 2005). A cryobank of these cells would add great flexibility to their use by allowing, among other things, shipment of cells to investigators and/or clinicians and adequate time for donor characterization and/or potential testing. To achieve this overall goal, we propose to begin with the following Specific Aims: (I) Optimization of collection, transportation and processing of extracted teeth; (II) Opt imization of cryopreservation of tooth derived stem cells; and (III) Final development of optimized, cGTP protocols for development of a tooth stem cell bank for distribution and use. Ultimate feasibility of developing a cryobank of DPSCs will be considere d achieved if e90% functional recovery of these cells is retained using the most sensitive assay available when compared to their unfrozen counterparts. Public Health Significance: Stem cells can develop into different tissues types in the body. Post-nata l, or adult stem cells offer an alternative to obtaining stem cells from embryos. Such stem cells exist in human teeth, but more research is required before these cells can have direct clinical use. A bank of frozen stem cells from teeth would be ideal to facilitate this research. This proposed project would optimize methods for processing and freezing these cells for ease of distribution for research, testing, and eventually clinical use.