Bioengineered corneal epithelial cell sheet from mesenchymal stem cells-A functional alternative to limbal stem cells for ocular surface reconstruction.

Limbal stem cell deficiency (LSCD) is the loss of limbal stem cells that reside in the corneoscleral junction resulting in vision loss or blindness. Bilateral LSCD is usually treated by allogeneic corneal transplantation, with instances of tissue rejection or failure in long-term follow-up. This study aims to use adipose mesenchymal stem cells (ASC) as an alternative autologous cell source for treating bilateral limbal deficiency conditions. ASCs derived from rabbit fat tissue were differentiated into corneal epithelial lineage using limbal explant condition media. Apart from transdifferentiation, ASC sheets were developed to facilitate effective delivery of these cells to the damage site. A thermoresponsive polymer N-isopropylacrylamide-co-glycidylmethacrylate (NGMA) was synthesized and characterized to demonstrate ASC sheet formation. Transdifferentiated ASCs showed positive expression of corneal epithelial marker CK3/12 on immunostaining, supported by gene expression studies. in vivo studies by transplanting cell sheet in rabbit models of corneal injury showed clear and smooth cornea in comparison to the sham models. Histology revealed a sheet of cells aligned and integrated on to the injured corneal surface, 1 month posttransplantation. Identifying ASCs as an alternative cell source along with cell sheet technology will be a novel step in the field of corneal surface therapies.