Differential chemotactic effect of cementum attachment protein on periodontal cells

Selective re-population of the root surface by periodontal ligament cells is considered a key factor in periodontal regeneration. A recently isolated cementum attachment protein (CAP) has been shown to enhance fibroblast attachment. In the present study the potential of CAP to selectively attract periodontal ligament cells (PLC) was studied in vitro in a micro-chemotaxis system. Human periodontal ligament cells and gingival fibroblasts (GF) were compared for their chemotactic response to either cementum attachment protein or to fibronectin. Murine dermal fibroblasts (MDF) served as control, irrelevant to the periodontium. The chemotactic response of PLC to fibronectin at 10(-8) M was of a similar magnitude as that of GF (16 +/- 5 and 11 +/- 3 cells/field, respectively), but both were significantly lower than the response of MDF (28 +/- 3 cells/field). The chemotactic response of periodontal ligament cells to the cementum attachment protein at 10(-7) M was higher (36 +/- 5 cells/field) than that of gingival fibroblasts or murine dermal fibroblasts (14 +/- 2 and 16 +/- 2 cells/field, respectively). These results suggest that cementum attachment protein can influence the selective re-population of root surfaces by periodontal ligament cells.