Cyclosporin A on human corneal endothelium

Human corneal endothelial cells grown in culture medium were exposed to different concentrations of cyclosporin A in vitro. After 7 days, concentrations of the drug less than 1,000 ng/ml of medium were found nontoxic to the endothelial layer, while greater concentrations killed the cells in 1 hour to 48 hours, depending upon the concentration of the drug. Degenerative cytoplasmic vacuoles were the first sign of toxicity from the drug, leading in higher concentrations to eventual disintegration.