Application of autologous cryopreserved bone marrow mesenchymal stem cells for periodontal regeneration in dogs

Background: Stem cell based therapies have shown great promise in regenerative medicine and continue to generate wide interest in future clinical applications. However, the issue of storage and preservation of stem cells, for future clinical applications, still requires extensive investigation. Objective: The purpose of this study was to evaluate the effect of cryopreservation on the regenerative capacity of bone marrow stem cells in periodontal defects in dogs. Materials and methods: Bone marrow mesenchymal stem cells (BMSCs) were obtained from five Beagle dogs. After cryopreservation for one month the measure of cell viability, surface adherence ability, alkaline phosphatase activity and mineralized nodule formation was assessed. 26 periodontal fenestration defects (5mm×5mm) were created at a location of 5mm apical to the cementoenamel junction in experiment teeth. Cryopreserved BMSCs were transplanted into the defects using a collagen scaffold carrier. Freshly isolated BMSCs and collagen scaffold alone were used as controls. All animals were sacrificed eight weeks after surgery and specimens were evaluated by histomorphometry. Results: Cryopreservation had no discernible negative effect on BMSCs growth and differentiation in vitro. Both freshly isolated and cryopreserved BMSCs transplantations induced significantly better periodontal regeneration with newly formed cementum, alveolar bone and periodontal ligament compared with the application of collagen scaffold alone. Conclusion: Cryopreserved BMSCs showed no altered regenerative capacity compared with freshly isolated BMSCs in the application of periodontal regeneration