Phenotype of Dental Follicle Cells in Developing Mouse Mandibular First Molars

Objectives:Dental follicle is the fibrous tissue that surrounds the developing tooth germ, and it has been implicated to contain progenitors for cementoblasts, periodontal ligament cells and osteoblasts. The present study is to characterize the phenotype of the cultured cells obtained from the dental follicle of neonatal mouse mandibular first molars. Methods:Dental follicle cells obtained from tooth germs of 5,7,9-day-old Balb/c mice by 1% trysin were cultured in DMEM containing 15% fetal bovine serum and antibiotics. After 15-25 days, cells grew to confluence and subcultured. Results:Immunohistological staining for anti-vimentin showed that all the cells were stained positively while negative for anti-cytokeratin, which demonstrated that all the cells were originated from mesenchyme. The isolated cells were apparently polymephic and there were two types of cells, some were cuboidal and their cytoplasm were filled with abundant granules, the other were spindle-shaped, fibroblast-like cells with processes. Type ¢ñand ¢ó collagen were expressed cytochemically. When cultured in conditioned mineralising media, the cells formed mineralised nodules. Conclusions:Thus, based on all the above characteristics, the cultured cells appeared to be undifferentiated mesenchymal cells from the dental follicle and had the potential to differentiate into bone-forming and collagen-forming cells. Supported by National Natural Scientific Foundation of China.