When ophthalmologists perform eye surgery, they often scrape off some human corneal epithelium and discard it. The CAAT-sponsored researchers have grown these epithelial cells in culture dishes and are refining their culture technique so the cells can be grown in quantities large enough for experimentation. Availability of cultured human corneal epithelium would allow scientists to develop human cell tests from in vitro methods currently under study in animal cell cultures. The researchers have one such method in mind, which they developed to study wound healing in rabbit corneal epithelium. When the surface of a rabbit or human eye receives a minor injury, healthy epithelial cells migrate over the wound and proliferate to heal it.
Toxic chemicals slow the healing response.
To measure this effect, the investigators wound normal and toxicant-treated rabbit corneal epithelium in vitro. They stain the wounds and use time-lapse photography to measure the rate of wound healing. The degree to which a substance slows the response is a measure of the substance's toxicity. The investigators have discovered that when exposed to certain chemicals, the human cells in vitro show a change in the rate of wound healing similar to that seen in rabbit eye cells, suggesting that the methods developed for the rabbit cell cultures can be applied to the study of toxicity in humans. Another potential benefit of this research is the possibility that scientists may find chemicals that increase the rate of wound healing, leading to drugs that can speed healing in patients with eye injuries.