Corneal Organ Culture Model for Assessing Epithelial Recovery After Surfactant Exposure

We previously reported the use of an ex vivo model of bovine corneal organ culture for predicting ocular irritation and evaluating acute chemical toxicity. Since the ability to recover after chemical exposure is a key parameter for assessing ocular toxicity of test chemicals, we sought to determine if cultured porcine cornea is able to recover after surfactant exposure and if functional recovery might be used as an ex vivo parameter for an ocular toxicity assay. Corneal chemical injury was created by placing a 7‐mm circular filter paper soaked in different concentrations of sodium dodecyl sulfate (SDS) on the center of porcine corneas for 2 minutes. The corneas exposed to surfactant with mild irritation (1% and 3% SDS, Draize score < 16.9) were able to recover from the initial damage, but no evidence of recovery was observed after exposure to surfactant with severe irritation (15% SDS, Draize score 59.2) as assessed by reestablishment of epithelial barriers. There was a concentration‐dependent increase in fluorescein retention in SDS‐exposed corneas. Furthermore, NF‐κB DNA‐binding activity was greatly altered after exposure to SDS in a concentration‐dependent manner. Our data suggest that functional corneal recovery after surfactant exposure correlates with known toxicity testing in vivo and may serve as a key endpoint for predicting ocular irritation of test chemicals and consumer products.