PRESENCE OF ENDOGENOUS CHEMOTACTIC FACTORS FOR PERIODONTAL-LIGAMENT CELLS IN BOVINE

When bovine cementum and bone were subjected to sequential dissociativ e extraction first with 4 M guanidine HCl ('G' extract) and then with 4M guanidine HCl/0.5 M,EDTA ('E' extract), high chemotactic activities for periodontal ligament cells were detected in the 'G' extracts usin g modified Boyden chambers. The chemotactic activities in both tissue extracts were destroyed by trypsin and heat. However, the activities i n bone extracts were more heat-stable than those in cementum. When bot h tissue extracts were separated into bound and unbound fractions by D EAE-Sephacel ion-exchange chromatography, the chemotactic activities i n cementum were detected in the unbound fractions, and those in bone i n the bound fractions, which were eluted by 1M NaCl. These results sug gest that cementum and bone contain different chemotactic protein fact ors for periodontal ligament cells.