• This study discusses the idea of using amniotic membrane as a niche environment for culturing limbal stem cells.

    The authors say that an animal model of limbal stem cell deficiency and transplantation might not only replace limbal stem cells by providing new healthy corneal epithelial cells but also restore the lost niche of the limbal stromal layer, causing the regression of vessels and rearrangement of the corneal stromal lamellae.

    They explain that several mechanisms have been proposed for regulation and maintenance of stem cells in the limbus of the cornea. They say the preferred hypothesis is that their niche, which is a special microenvironment, regulates adult stem cells, including the limbal stromal cells and their underlying basement membrane, maintaining limbal stem cells in an undifferentiated state.

    The purpose of the author’s ex-vivo expansion technique is to develop a method that will enable the culture of a small number of stem cells that could be expanded in a defined cultured system while preserving the original characteristics and properties of the stem cells.

    Studies have been conducted of cases with pre-existing central corneal stromal opacity treated by transplantation of limbal stem cells followed by penetrating keratoplasty. They say the results indicate that amniotic membrane can provide the niche environment for cultured limbal stem cells and maintain the limbal-like environment for the transplanted area of the cornea.