Abstract
The cornea of the eye provides a privileged transparency and unique refractive properties that enable light to enter the inner ocular environment and reach the posteriorly located retina for the achievement of vision. The preservation of corneal physiological functionality greatly depends on maintaining a delicate equilibrium between a vast array of defensive immunological mechanisms designed to combat pathologic insult and injury to the cornea. The corneal epithelium serves as ground zero for an amalgamation of immunoregulatory pathways that efficiently modulate the ocular surface mucosal microenvironment in conjunction with neighboring structures such as the conjunctiva and lacrimal glands. This article reviews the most recent findings in corneal surface immunity and its regulation by the corneal epithelium. Understanding the manifestations of immunoregulation by the corneal epithelium is critical to developing more specific and efficient treatment protocols that can prevent acute patients from developing chronic and autoimmune disease. Moreover, the ocular surface mucosal microenvironment shares numerous common immune pathways with mucosal-associated, gut-associated, and bronchial-associated lymphoid tissue. Therefore, further basic and translational research on corneal surface immunoregulation can offer promising therapeutic applications to similar mucosal tissues throughout the body and benefit numerous patients that suffer from disease catalyzed by failure of immunoregulation.
Keywords: Corneal epithelium, toll-like receptors, inflammation, antigen-presenting cells, immunoregulation, autoimmune disease, Ocular Immune Responses, cornea, MALT, chronic corneal inflammation, Sjogren's Syndrome
16