Engineered Basement Membranes for Regenerating the Corneal Endothelium.

Basement membranes are protein-rich extracellular matrices (ECM) that are essential for epithelial and endothelial tissue structure and function. Aging and disease cause changes in the physical properties and ECM composition of basement membranes, which has spurred research to develop methods to repair and/or regenerate these tissues. An area of critical clinical need is the cornea, where failure of the endothelium leads to stromal edema and vision loss. Here, an engineered basement membrane (EBM) is developed that consists of a dense layer of collagen IV and/or laminin ≈5-10 nm thick, created using surface-initiated assembly, conformally attached to a collagen I film. These EBMs are used to engineer a corneal endothelium (CE) that mimics the structure of Descemet's membrane with a thin stromal layer, toward use as a graft for lamellar keratoplasty. Results show that bovine and human CE cells form confluent monolayers on the EBM, express ZO-1 at the cell-cell borders, and achieve a density of ≈1600 cells mm-2 for 28 and 14 d, respectively. These results demonstrate that the technique is capable of fabricating EBMs with structural and compositional properties that mimic native basement membranes and that EBM may be a suitable carrier for engineering transplant quality CE grafts.