Characterization of chemotactic migration and growth kinetics of canine knee ligament fibroblasts

Migration and proliferation of ligament fibroblasts are essential for the h ealing of ligament injuries. This study was designed to evaluate the migrat ion of intraarticular (anterior and posterior cruciate) and extraarticular (medial and lateral collateral) Ligament fibroblasts in response to cytokin es and to determine the effect of cell passage on cell proliferation. Recom binant human platelet-derived growth factor, hepatocyte growth factor/scatt er factor, and bone morphogenic protein-2 stimulated the migration of all l igament cells in a dose-dependent manner, with optimal migration at 10 ng/m l. Recombinant human epithelial growth factor preferentially stimulated the migration of intraarticular ligament fibroblasts, whereas recombinant huma n interleukin-l was more effective with extraarticular ligament fibroblasts . Recombinant human insulin-like growth factor-1, insulin-like growth facto r-2, transforming growth factor-beta, and fibroblast growth factor-had no s ignificant effect on the migration of ligament-derived fibroblasts. These d ata suggest that specific cytokines stimulate the migration of knee Ligamen t fibroblasts and provide a rationale for possible therapeutic approaches t o optimize ligament healing. Fibroblasts derived from the anterior cruciate ligament have been shown to proliferate at a slower rate than those derive d from the medial collateral ligament. We have extended these observations and have demonstrated that fibroblasts from both the posterior and anterior cruciate ligaments proliferate at a slower rate than lateral and medial co llateral ligament-derived fibroblasts. The differences between the growth r ates of intraarticular and extraarticular fibroblasts become insignificant with serial passaging of the cells.