Proliferative response of cultured human tenon's capsule fibroblasts to platelet-derived growth factor isoforms

Background: Although platelet-derived growth factor (PDGF) has been thought to be critical in the wound-healing response of Tenon's capsule fibroblasts after glaucoma filtration surgery, no information is currently available concerning the proliferative effect of PDGF isoforms on this cell type. The aim of the present study was to evaluate the proliferative effect of PDGF-AB heterodimer and PDGF-AA and -BB homodimers on cultured human Tenon's capsule fibroblasts. Methods: Human Tenon's capsule fibroblasts, cultured under serum-free conditions, were stimulated with PDGF-AA, -AB and -BB isoforms in concentrations ranging from 1 to 100 ng/ml. Cell numbers were determined on days 1, 3, 5 and 7, using a cell counter. Results: Addition of PDGF-AB and -BB led to a dosedependent increase in cell proliferation. A maximal response (79.9% over control) was obtained after 7 days with 30 ng/ml of PDGF-BB, with an EC₅₀ of 8.9 ng/ml. The maximal increase in cell proliferation caused by PDGF-AB (30 ng/ml) was 54.9%, with an EC₅₀ of 12.5 ng/ml. Stimulation with PDGF-AA revealed a significant effect only with concentrations higher than 30 ng/ml. Conclusion: Our results indicate that PDGF-AB and -BB isoforms are potent stimulators of proliferation of human Tenon's capsule fibroblasts, suggesting that PDGF-AB and -BB isoforms play an important role in the wound-healing response after glaucoma filtration surgery.Presented in part at the annual meeting of the Deutsche Ophthalmologische Gesellschaft, Mannheim, September 1996