BOVINE CEMENTUM EXTRACT INFLUENCES MURINE DENTAL FOLLICLE CELLS IN-VITRO

This study evaluated the attachment, chemo-attractive, proliferative a nd mineralization inductive potential of a bovine cementum extract (CP E) on newborn murine dental follicle cells (MDFC) in vitro. Cementum e xtract was partially purified by DEAE-cellulose chromatography. A band representing an M-r of 55,000 was excised from the gel and the protei n(s) were electroeluted. Attachment assays revealed that CPE (1.0 mu g /ml) promoted MDFC attachment by 96% in comparison with collagen type I (5 mu g/ml), and was five-fold greater compared with serum-free medi a (SFM), (P < 0.05). Between 1 and 5 days CPE at 1.0 mu g/ml and colla gen type I at 5 mu g/ml sustained more than 75% attachment and spreadi ng of MDFC when compared to SFM (P < 0.05). Contrary to other reports, fibronectin (0.5 mu g/ml) was more potent than CPE in promoting MDFC chemoattraction (P < 0.05). MDFC proliferation was stimulated by CPE ( 0.125 mu g/ml); but this response was elicited only when CPE was used together with 10% FBS (37.3%) or 0.2% FBS (76%) (P < 0.05). Alkaline p hosphatase expression by MDFC was increased by CPE (1.0 mu g/ml), in c omparison to the control. Calcium deposits were detected by von Kossa staining in 14-day MDFC cultures treated with CPE. Nodule formation an d its mineralization in long-term MDFC cultures were induced by CPE (1 .0 mu g/ml). Molecule(s) contained in CPE appear to regulate various b iological activities in MDFC, indicating that CPE could play a key rol e in selecting progenitor cells required for the process of cementogen esis during development.