Ultraviolet-induced effector molecules in ocular surface diseases: regulation of expression in vitro and in vivo

Pterygium is a common, recurrent, inflammatory, and sight-threatening complication of the human eye. The disease is characterised by a fleshy vascular growth that gradually covers the ocular surface if left untreated. Limbal dysplasia is a less common disease but in some regards this disease behaves much like a pterygium. We have generated considerable laboratory based data that these ocular surface disorders may be triggered by ultraviolet (UV) radiation and this fits well with the extensive epidemiological evidence. To data the only form of treatment is surgical intervention, often with adjunctive topical agents that can cause other more severe complication of the eye. The aim of this investigation is to determine the effectiveness of agents such as retinoic acid and interferons to block or inhibit the down-stream effects of UV radiation. Currently, we have preliminary data that suggests these agents can significantly reduce several molecules that are activated by UV in cultured ocular surface cells. Furthermore, we have clinical evidence that retinoic acid and interferon can resolve both pterygia and conjunctival dysplasia in a small group of patients. If successful, these agents may replace costly and time-consuming surgical approach to treatment.