Purpose
The purpose of this study was to investigate the effect of recombinant pigment epithelium derived factor (rPEDF), secreted by ARPE-19 cells transfected with the human PEDF gene and transplanted subconjunctivally in healthy rabbits and in rabbits in which corneal neovascularization was elicited by a chemical burn.
Methods
Sixteen grey Chinchilla Bastard rabbits were randomly assigned to 3 groups; neovascularization was induced in groups A and B by alkali cauterization. After seven days, non-transfected cells were implanted subconjunctivally in group A and PEDF-transfected cells were implanted subconjunctivally in group B and C (non-cauterized). In vivo rPEDF secretion was analyzed by immunoblotting of conjunctival tissue biopsies taken at different time points. Digital photographs acquired on days 7, 14, and 21 after cauterization were evaluated for lead vessel length, vascular invasion area, and overall neovascularization rate.
Results
At days 14 and 21 after cauterization significant differences were observed between groups A and B in lead vessel length (day 21: 5.11 ± 1.22, 3.79 ± 0.59 mm, respectively), vascular invasion area (day 21: 34.86 ± 4.92, 19.2 ± 5.03 mm2, respectively), and rate of corneal neovascularization. Compared to group A neovascularization in group B was reduced by 39.1% on day 14 and 44.9% on day 21. Analysis of conjunctival tissue showed that rPEDF was secreted by the transplanted PEDF-transfected cells.
Conclusions
Subconjunctivally transplanted, PEDF-transfected ARPE-19 cells secrete rPEDF, which effectively inhibits the corneal neovascularization elicited by alkali cauterization.
Keywords: 480 cornea: basic science •
609 neovascularization •
538 gene transfer/gene therapy