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Abstract
Stem cells are cells that can proliferate that most unlimited potential, maintaining a pool of growing and dividing cells, with the added abilities that some cells can differentiated into specific cell types. Stem cells are present in all self reviewing tissue and have unique characteristics that enable them to control cell replacement during homeostasis and tissue repair.
The ocular surface is made up of two distinct types of epithelial cells, constituting the conjunctival and corneal epithelial. These epithelial are stratified squamous and none keratinized. Although anatomical continous with each other at the corneoscleral limbus
Limbal stem cells have been localized to the palisades of Vagot in the corneal limbus .The microenvironment of the limbus is considered to be important in maintaining stemness of stem cell. The also act as barrier to conjunctival epithelial cells and prevent the from migrating on to the corneal surface.
In certain pathological conditions, the limbal stem cells may be destroyed partial or completely resulting in varying degree of stem cell deficiency with its characteristics clinical feature. These include conjunctivalization of the cornea with vascularization, appearance of goblet and irregular and unstable epithelium