Transplanted Bone Marrow derived Cells Differentiated toTooth, Bone and Connective Tissues in Mice

抄録

Teeth are important structures for masticatory and phonetic purposes. Loss of teeth decreases these functions leading to impaired quality of life. Missing teeth replaced by tooth regeneration may be possible with emerging advances in stem cell biology and tissue engineering. Recent investigations have demonstrated that bone marrow derived cells (BMDC) can differentiate into cells other than blood cells. In the present study, the ability of BMDC to differentiate into tooth forming tissues was investigated using bone marrow transplantation model. BMDC from green fluorescent protein (GFP) transgenic mice were transplanted into 8-week old, C57BL/6 immunocompromised mice, which underwent 10-Gy whole body lethal irradiation. Immunohistochemical analysis revealed that bone marrow cells are positive to GFP, confirming successful bone marrow transplantation. Diffusedly GFP-positive cells were observed within the dental pulp of mouse incisor. GFP-positive cells in the dental pulp have arborescent processes resembling dendritic cell-like cells. Some odontoblast-like cells were also positive to GFP. Cells positive to GFP were observed in the cervical loop region and periodontal ligament. Langerhans cells in the oral epithelium, stromal fibroblasts, blood vessels and osteoclasts were also positive to GFP. These results indicate that BMDC have the ability to differentiate into tooth, bone and connective tissues.