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Objective To study the effect of topical cyclosporine on lymphocyte activation within the conjunctiva of patients with moderate to severe dry eye syndrome (Sjogren and non-Sjogren). Methods Biopsy specimens were obtained at baseline and after 6 months of cyclosporine treatment from eyes of 32 patients with moderate to severe dry eye syndrome; 19 were cyclosporine treated (0.05% cyclosporine, n = 13; 0.1% cyclosporine, n = 6) and 13 were vehicle treated. Within this group there were 12 with Sjogren syndrome and 20 with non–Sjogren syndrome. Biopsy tissue was analyzed using immunohistochemical localization of binding of monoclonal antibodies to lymphocytic markers CD3, CD4, and CD8 as well as lymphocyte activation markers CD11a and HLA-DR. Results In cyclosporine-treated eyes, biopsy results of conjunctivae showed decreases in the number of cells positive for CD3, CD4, and CD8, while in vehicle-treated eyes, results showed increases in these markers, although these differences were not statistically significant. Following treatment with 0.05% cyclosporine, there was a significant decrease in the number of cells expressing the lymphocyte activation markers CD11a (P Conclusion Treatment of dry eye syndrome with topical cyclosporine significantly reduced the numbers of activated lymphocytes within the conjunctiva.

Morphologic alterations of the extracellular matrix in diabetes include thickening of the basement membrane and, as evidenced in the corneal epithelium, a decrease in the area of the basal cell membrane occupied by hemidesmosomes. To determine if the abnormal basement membrane in diabetes has altered epithelial recognition of sites for hemidesmosome formation and if diabetic epithelium can recognize sites for hemidesmosome formation on normal basement membrane, we recombined epithelial sheets and corneal stromas with denuded basement membranes in vitro using diabetic and control corneas. In recombinations of diabetic epithelium on normal stromas, the area of the basal cell membrane occupied by hemidesmosomes was 10.7%, significantly less than control recombinations (19.5%). Similarly, in recombinations of normal epithelium on diabetic stromas, the value (8.6%) was significantly decreased from control. These data may indicate altered cell-extracellular matrix interactions in diabetes.

From the perspective of an epithelial cell biologist, I have several concerns regarding healing of the epithelium after excimer laser ablation for change of corneal refraction. One concern is the hyperplastic response of the epithelium when a wound is made in the stroma. The preexisting curvature of the cornea is restored in such wounds by increased layers of epithelial cells. 1-3 If such a response occurs after ablation, the optical effect of the surgery would be unstable and would regress. Anecdotal statements by some investigators using laser ablation as a technique of refractive surgery indicate that if the edge of the area tapers gradually toward the deepest ablation zone, the hyperplastic response does not occur. Such preliminary observations need to be documented by careful animal studies. A second concern is that ablation of the anterior stroma removes the basement membrane and the anchoring fibril network, structures that are needed for