Effects of platelet-derived growth factor on endothelial wound healing of human corneas

To investigate the effects of platelet-derived growth factor (PDGF) on endothelial wound healing of organ-cultured human corneas.

The endothelia of paired human donor corneas (age, 71 +/- 11 years; total 84 pairs) were mechanically wounded (area, 5.6 +/- 0.8 mm2). Of each pair, one cornea was treated with 10 ng/ml human recombinant PDGF-BB while its mate served as control. The endothelial wound closure time was assessed by daily staining of the corneas with trypan blue. Morphometric data (endothelial cell density, shape, coefficient of variations) were obtained in the wound area after alizarin red staining. DNA synthesis was assessed using 3H-thymidine autoradiography.

Although significant, the time of complete wound closure shortened only marginally on addition of PDGF to the culture medium. In the closed wound center (between 4 and 9 days), all corneas exposed to PDGF had significantly higher endothelial cell densities (737 +/- 126 cells/mm2) than the control corneas (515 +/- 89 cells/mm2). Fifteen days after wounding, the mean endothelial cell density averaged 526 +/- 93 and 708 +/- 135 cells/mm2 in the control and PDGF-treated groups, respectively. PDGF did not affect the final cell shape within the closed wounds. DNA synthesis was significantly but only marginally enhanced in PDGF-treated corneas.

In organ-cultured human corneas, PDGF-BB promotes endothelial wound healing predominantly by cell migration, at least in corneas from senior donors.