Published online Jun 26, 2015. doi: 10.4252/wjsc.v7.i5.806
Peer-review started: August 30, 2014
First decision: December 17, 2014
Revised: January 5, 2015
Accepted: April 16, 2015
Article in press: April 20, 2015
Published online: June 26, 2015
Processing time: 305 Days and 5.4 Hours
Major advances are currently being made in regenerative medicine for cornea. Stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there are many challenges ahead given the singularities of each cellular layer of the cornea. This review recapitulates the current data on corneal epithelial stem cells, corneal stromal stem cells and corneal endothelial cell progenitors. Corneal limbal autografts containing epithelial stem cells have been transplanted in humans for more than 20 years with great successful rates, and researchers now focus on ex vivo cultures and other cell lineages to transplant to the ocular surface. A small population of cells in the corneal endothelium was recently reported to have self-renewal capacity, although they do not proliferate in vivo. Two main obstacles have hindered endothelial cell transplantation to date: culture protocols and cell delivery methods to the posterior cornea in vivo. Human corneal stromal stem cells have been identified shortly after the recognition of precursors of endothelial cells. Stromal stem cells may have the potential to provide a direct cell-based therapeutic approach when injected to corneal scars. Furthermore, they exhibit the ability to deposit organized connective tissue in vitro and may be useful in corneal stroma engineering in the future. Recent advances and future perspectives in the field are discussed.
Core tip: Corneal stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there are many challenges ahead given the singularities of each cellular layer of the cornea. To date, the most widespread clinical approach to regenerative medicine in the eye has been the utilization of limbal stem cells for ocular surface diseases. New therapeutic strategies are under development due to the recent identification of corneal stromal stem cells and corneal endothelial cell progenitors. This review recapitulates the current advances and discusses future perspectives in the field.