Sunil Kim1, Sukjoon Lee2, Han-Sung Jung3, Sun-Young Kim4, Su-Jung Shin5, Mo K Kang6, Euiseong Kim7. 1. Microscope Center, Department of Conservative Dentistry and Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, South Korea. 2. BK21 PLUS Project, Yonsei University College of Dentistry, Seoul, South Korea. 3. Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 PLUS Project, College of Dentistry, Yonsei University, Seoul, South Korea. 4. Department of Conservative Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea. 5. Department of Conservative Dentistry, Gangnam Severance Dental Hospital, Yonsei University College of Dentistry, Seoul, South Korea. 6. Section of Endodontics, Division of Constitutive and Regenerative Sciences, UCLA School of Dentistry, Los Angeles, California. 7. Microscope Center, Department of Conservative Dentistry and Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, South Korea. Electronic address: andyendo@yuhs.ac.
Abstract
INTRODUCTION: Several studies have attempted to use human dental pulp stem cells (hDPSCs) for pulp-dentin complex regeneration in vitro. However, the safety of such applications should be first evaluated in vivo before their use in clinical trials. The purpose of this study was to investigate the in vivo fate of intrapulpally transplanted hDPSCs. METHODS: hDPSCs were isolated and cultured from impacted third molars. In vivo experiments were performed using 7-week-old male BALB/c nude mice. Under deep anesthesia, 1 × 105 hDPSCs were transplanted in mice via the tail vein for intravenous injection or into the pulp chamber for intrapulpal transplantation. A total of 56 mice, 28 per group, were used. Mice were sacrificed at different time points, and the numbers of hDPSCs in the organs were analyzed quantitatively. In addition, qualitative analysis was performed to detect intrapulpally transplanted hDPSCs. RESULTS: Intravenously injected hDPSCs were mostly distributed to the lungs and rarely detected in other organs at all observed time points. The hDPSCs transplanted into the pulp chamber rarely migrated to other organs over time. CONCLUSIONS: These data indicate a differential distribution of transplanted hDPSCs between the intravenous and intrapulpal route and show the safety of pulpal transplantation of hDPSCs.
INTRODUCTION: Several studies have attempted to use human dental pulp stem cells (hDPSCs) for pulp-dentin complex regeneration in vitro. However, the safety of such applications should be first evaluated in vivo before their use in clinical trials. The purpose of this study was to investigate the in vivo fate of intrapulpally transplanted hDPSCs. METHODS: hDPSCs were isolated and cultured from impacted third molars. In vivo experiments were performed using 7-week-old male BALB/c nude mice. Under deep anesthesia, 1 × 105 hDPSCs were transplanted in mice via the tail vein for intravenous injection or into the pulp chamber for intrapulpal transplantation. A total of 56 mice, 28 per group, were used. Mice were sacrificed at different time points, and the numbers of hDPSCs in the organs were analyzed quantitatively. In addition, qualitative analysis was performed to detect intrapulpally transplanted hDPSCs. RESULTS: Intravenously injected hDPSCs were mostly distributed to the lungs and rarely detected in other organs at all observed time points. The hDPSCs transplanted into the pulp chamber rarely migrated to other organs over time. CONCLUSIONS: These data indicate a differential distribution of transplanted hDPSCs between the intravenous and intrapulpal route and show the safety of pulpal transplantation of hDPSCs.