Phenotypic study of a case with successful transplantation of ex vivo expanded human limbal epithelium for unilateral total limbal stem cell deficiency

Epithelial stem cells in corneal regeneration and epidermal gene therapy

“…A significant improvement was the use of supporting materials for cell culture, transportation and transplantation onto patients, such as fibrin glue [41][42][43], amniotic membrane [87][88][89][90], polymers [91], collagen sponges or strips, devitalized membranes or polymers (reviewed in [92]). As with culture media, however, the issue of holoclone preservation arises when different substrates are proposed for limbal cell cultivation.…”

“…When the amnion is to be used as a substrate for cultured cells, the amniotic epithelium is usually removed in order to allow their attachment. Amniotic membrane has been used for cell cultivation by numerous investigators, either with or without a 3T3 feeder layer [87][88][89][90]. When limbal keratinocytes cultured on such support were applied to the eye affected by different diseases, the treatment resulted in notable improvement of the ocular surface [93,94].…”

Niche regulation of corneal epithelial stem cells at the limbus

“…Importantly, amniotic membrane transplantation alone is sufficient to restore the normal corneal epithelial phenotype in human corneas with partial limbal SC deficiency [96][97][98], indicating that amniotic membrane helps expand residual limbal epithelial SCs in vivo. The above clinical discovery has led others to successfully transplant such an ex vivo expanded human limbal epithelial tissue to treat human corneas with total limbal SC deficiency [34,99,100]. Because no murine 3T3 fibroblast feeder layer is needed, human amniotic membrane may serve as an ex vivo surrogate niche (for review see [39]).…”

Limbal Stem Cell Transplantation and Corneal Neovascularization

“…Since 1997's landmark report, a variety of culture techniques have been developed to produce contiguous epithelial cell sheets for transplantation. These techniques can be broadly defined as either explant culture in which cells migrate out from limbal tissue attached to a surface (Grueterich et al, 2002b, Koizumi et al, 2001a, Koizumi et al, 2001b, Sangwan et al, 2006 or suspension culture in which cells are released from enzymatically digested extracellular matrix before culture (Daya et al, 2005, Pellegrini et al, 1997. The aforementioned methods have been used in studies to culture limbal epithelial cells successfully, on either a growth-arrested 3T3 fibroblast feeder layer or an amniotic membrane (AM), with varying results (Kim et al, 2004, Zito-Abbad et al, 2006.…”

“…Since then, transplantation of cultivated epithelial (stem) cells has become a treatment of choice for numerous LSCD patients worldwide. While the outcomes are promising, the variability of methodologies used to expand the cells, points to an underlying need for better standardization of ex vivo cultivation-based therapies and their outcome measures , Ti et al, 2004, Grueterich et al, 2002b, Kolli et al, 2010. This chapter provides a general update on LSCD pathogenesis, the key role of stem cells and their niche in maintaining corneal homeostasis and avascularity and a general update on LSCD pathogenesis.…”