ENHANCING EFFECT OF PLATELET-DERIVED GROWTH-FACTORS ON MIGRATION OF CORNEAL ENDOTHELIAL-CELLS

To investigate the role of platelet-derived growth factor (PDGF) in corneal wound healing, we examined the effect of human natural PDGF, recombinant PDGF-BB, and PDGF-AA on the migration of rabbit corneal endothelial cells. In a modified Boyden chamber in fetal bovine serum-free conditions, natural PDGF and PDGF-BB, at a concentration of 1-3 or 10 ng/ml, enhanced the migration of endothelial cells, whereas at a higher concentration (10 or 30 ng/ml), this enhanced migration was suppressed; the optimal concentration range for enhancing migration was 3-10 ng/ml), this enhanced migration was suppressed; the optimal concentration range for enhancing the migration. Natural PDGF and PDGF-BB activity was found for up to 6 h after the beginning of culture, and was completely blocked by anti-PDGF neutralizing antibodies. A checkerboard assay demonstrated that PDGF-BB had a chemotactic effect on the corneal endothelial cell migration. These results suggest that natural PDGF and PDGF-BB, but not PDGF-AA, are involved in corneal wound healing by stimulating the migration of corneal endothelial cells.