The limbal epithelium of the eye--a review of limbal stem cell biology, disease and treatment.

The limbus is a narrow band of tissue that encircles the cornea, the transparent 'window' into the eye. The outermost layer of the cornea is the epithelium, which is necessary for clear vision. The limbus acts as a 'reservoir' for limbal stem cells which maintain and regenerate the corneal epithelium. It also functions as a barrier to the conjunctiva and its blood vessels. Limbal stem cell deficiency is a general term for diseases which are characterised by the impairment of the limbus, limbal stem cells and their ability to replenish the corneal epithelium through proliferation and differentiation. Consequently, sufferers experience chronic pain and progressive blindness. This paper will highlight the salient milestones of limbal stem cell biology and potential future treatments for limbal stem cell deficiency.