The cornea demonstrates a form of immune privilege different from that observed in the anterior uvea. Immune privilege of the cornea is multifactorial. Normal limbal physiology is a major component, especially the maintenance of avascularity and lack of APCs in the mid- and central cornea. The absence of APCs and lymphatic channels partially inhibits afferent recognition in the central cornea. The absence of postcapillary venules centrally can limit the efficiency of effector recruitment, although effector cells and molecules can infiltrate even avascular cornea. Another factor is the presence of intact immuno-regulatory systems of the anterior chamber to which the corneal endothelium is exposed. Finally, effector blockade likely provides relative immune privilege to the cornea. (See Clinical Example 3-1.)
Figure 3-1 Endothelial graft rejection with stromal and epithelial edema on the trailing aspect of the migrating Khodadoust line (inset).
Excerpted from BCSC 2020-2021 series: Section 9 - Uveitis and Ocular Inflammation. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.