Amniotic Membrane Epithelial Cells Can Be Used as Substitute for Corneal Endothelial Cells

Abstract

Purpose: : To investigate gene profile expressed in human corneal endothelial cells (HCECs) and amniotic membrane epithelial cells (AMECs), and to determine the feasibility of corneal reconstruction utilizing AMECs sheets in a rabbit model.

Methods: : The histology of AMEC and HCEC was investigated by scanning electron microscope and transmission electron microscope. Gene expression of vimentin, ABCG2, N-cadherin, VE-cadherin, E-cadherin, ZO-1, Connexin 43, Na⁺/K⁺ ATPase alpha1 and beta 1 in AMECs and HCECs were detected using RT-PCR and immunostaining. AMEC sheets were separated from fresh placenta by Dispase II digestion, and the cell viability was detected by Live/Dead assay. AMEC sheets were mounted on endothelium and Descemet membrane-denuded rabbit corneal and transplanted into recipient rabbit eyes, corneal thickness and transparency before and after surgery were examined by ultrasonic sound and slit-lamp microscope, respectively.

Results: : AMECs and HCECs showed similar density, compact cell-cell contact, and inerratic cell shape in vivo. AMECs showed pentagonal shape with abundant microvilli on the apical side, while HCECs showed hexagonal shape without microvilli. RT-PCR showed that vimentin, ABCG2, N-cadherin, ZO-1, Connexin 43, Na⁺/K⁺ ATPase alpha1 and beta 1 genes were expressed in both AMECs and HCECs. VE-cadherin was preferentially expressed in HCECs, while E-cadherin was only expressed in AMECs. Immuno-fluorescent staining showed the same pattern. AMECs sheets were successfully separated from fresh placenta with high viability. Rabbit cornea with AMECs maintained high transparency and normal thickness for at least two weeks after transplantation.

Conclusions: : AMECs have similar shape and function as HCECs, they can be used as substitute for corneal endothelial cells.

Keywords: cornea: endothelium • cornea: basic science