Effect of Rho-associated kinase inhibitor on human corneal endothelial cell apoptosis

PURPOSE: To evaluate whether exposure to Rho-associated protein kinase (ROCK) inhibitor will promote human-cultured corneal endothelial cells (CECs) survival in a commercial storage medium. SETTING: Edith Wolfson Medical Center, Holon, and Sheba Medical Center, Tel Hashomer, Israel. DESIGN: Experimental study. METHODS: Fragments of human donor corneolimbal rings were stored in commercial storage media for 1 week, half with the addition of 10 μM ROCK inhibitor (Y-27632). Evaluation of CECs for early and late apoptosis rates was performed using anti-human CD166 antibody and flow cytometric double staining analysis of propidium iodide and Annexin V. RESULTS: CECs of 6 corneolimbal rings demonstrated a reduced early apoptosis rate (4.35% ± 1.07% vs 12.18% ± 5.5%, P = .026) and a reduced late apoptosis rate (5.5% ± 2.39% vs 9.43% ± 2.61%, P = .004) compared with control. Subsequently, the rate of apoptotic CECs expressing ROCK was significantly lower in cells exposed to ROCK inhibitor compared with cells that were not (19.01% ± 4.17 vs 30.42% ± 4.27, P < .001). CONCLUSIONS: ROCK inhibitor reduced endothelial cell loss in vitro and might be used to limit or slow CEC loss in donor corneal tissue during eye banking. This might be a promising new method for promoting future graft survival.