Characterisation and evaluation of the impact of microfabricated pockets on the performance of limbal epithelial stem cells in biodegradable PLGA membranes for corneal regeneration

Abstract

Scarring of the cornea affects thousands of people every year, significantly reducing the quality of life and potentially leading to corneal blindness. Although cultured limbal epithelial cells have been used to regenerate scarred corneas for more than 15 years, the culture strategies do not deliver cells under the physiological conditions they experience in vivo. One of the main characteristics of stem cells is their ability to self-renew to maintain a tissue for a lifetime. Stem cells’ unique characteristics are thought to be at least partially due to their location within enclosed protective microenvironments or niches. For corneal stem cells these are located in intricate microenvironments or niches situated within areas of the limbal region known as the Palisades of Vogt. These are located in the limbus which is the area between the cornea and sclera. In this study we introduced micropockets into biodegradable microfabricated membranes and explored the potential contribution of these structures to limbal cell migration and their ability to deliver cells to a 3D cornea model. Membranes with micropockets were characterized using SEM, OCT, light microscopy and nanoindentation. Results indicate that the micropockets enhance the migration of cells from limbal explants and cells transfer readily from the membranes to the ex vivo cornea model.