Physiological pressure enhances the formation of tight junctions in engineered and native corneal endothelium.

Cells and tissues are influenced by environmental conditions. In vivo, the corneal endothelium is subjected to hydrostatic intraocular pressure (IOP) and to the hydrokinetic pressure of the moving aqueous humor in the anterior chamber. In this paper, we used a corneal bioreactor to recreate the IOP condition and investigated the effect of the in vivo hydrodynamic environment of corneal endothelial cells on the formation of tight junctions. Native ex vivo corneas and engineered corneal endothelia subjected to pressure showed an increase in ZO-1 expression at the cell periphery. Pressure also improved the corneal transparency of engineered and native corneas. Corneal thickness was accordingly reduced from 926 ± 70 μm to 651 ± 70 μm for the engineered corneal endothelium and from 847 ± 27 μm to 571 ± 23 μm for the native endothelium. These results suggest that the hydrodynamic pressure of the anterior chamber is important for the cell junction integrity of the corneal endothelium.