Human Omental Mesothelial Cells Exhibit a Corneal Endothelial-Like Cell Phenotype for Tissue Engineering of a Corneal Endothelium Biomimetic.

Purpose: To evaluate whether cultured human omental mesothelial cells (OMC) exhibit phenotypic and functional similarities to human corneal endothelial cells (CEC) and whether they can adhere to the corneal stroma and form a biomimetic corneal endothelium when grown on a human anterior lens capsule (HALC).

Methods: Human OMC were isolated from the greater omentum. Human B4G12 CEC were used as a reference for native and functional CEC phenotype whereas human mesenchymal stromal cells (MSC) served as a phenotypically distinct control group. OMC, CEC and MSC were compared using flow cytometry, immunofluorescence and qRT-PCR for lineage-specific markers, as well as through a transepithelial permeability assay. The adhesion capacity of OMC was also evaluated on both mouse corneal stroma and a decellularized HALC.

Results: Several cell-surface markers commonly expressed at high levels in MSC (CD13, CD105, CD73 and CD44) were detected at markedly lower levels in OMC and CEC. OMC and CEC, but not MSC, also shared a similar expression profile of key structural markers (pan cytokeratin, ZO-1, β-catenin, N-cadherin, COL4A2, COL8A2) and functional corneal endothelium markers (AQP1, ATP1A1, SLC4A11, CLCN-3). In addition, OMC demonstrated transepithelial permeability values comparable to those of CEC monolayers supporting their barrier-forming capacity. Both CEC and OMC formed cobblestone-like monolayers on mouse corneal stroma and OMC seeded onto HALC generated a bioconstruct that reproduced the key morphological and ultra-structural features of native corneal endothelium.

Conclusions: Overall, our findings show that cultured human OMC exhibit phenotypic and functional similarities to CEC. The ability of OMC to adhere to the corneal stroma and to generate a biomimetic corneal endothelium when combined with HALC highlights their potential use in corneal endothelial regeneration.