A SIMPLE ORGAN-CULTURE MODEL FOR ASSESSING THE EFFECTS OF GROWTH-FACTORS ON CORNEAL REEPITHILIALIZATION

The effects of growth factors on re-epithelialization of wounded human and bovine corneas were studied in a simple organ culture system. Exc isional trephine and epithelial scrape wounds were created on bovine a nd human corneo-scleral rings in which the endothelial corneal concavi ty was then filled with an agar-collagen mixture. Organ culture was un dertaken at 37 degrees C in a humidified 5% CO2 incubator with serum-f ree Medium 199 maintained at the level of the conjunctival epithelium. Rates of reepithelialization in response to addition of exogenous epi dermal growth factor (EGF), basic fibroblast growth factor (bFGF) and transforming growth factor type beta(1) (TGF-beta(1)) were assessed by image analysis. Corneal cultures could be maintained for up to 3 week s without significant stromal oedema or keratocyte deterioration and w ith little loss of epithelial architecture. Following wounding the cor nea reepithelialized in a similar fashion to that observed in vivo i.e . a lag phase followed by migration/proliferation and the reformation of an intact multilayered epithelium. EGF accelerated, basic FGF had n o effect on, and TGF-beta(1) inhibited the rate of corneal re-epitheli alization. Our organ culture model maintains corneal integrity and pro vides a practical system in which to study factors that modulate corne al reepithelialization following wounding. (C) 1996 Academic Press Lim ited