Analysis of the antibody repertoire in tears of dry-eye patients

Purpose: It has recently been suggested that dry-eye disease has an underlying autoimmune mechanism. This hypothesis is further supported by the successful treatment of the disease with immunomodulatory drugs such as cyclosporin A. Although it is known that tears contain antibodies, very little is known about the antibody repertoires in tears. It was the aim of this study to analyze the IgA antibody repertoire against ocular antigens in the tears of patients suffering from dry-eye disease and compare it to those of healthy volunteers. Methods. Two groups were examined: 20 healthy volunteers (controls) and 28 patients suffering from dry-eye disease. The patients were grouped according to the results of the basic secretory test. Patients with values less than or equal to 10 and subjective symptoms were classified as dry-eye patients. All tears were tested against Western blots of ocular antigens. For each Western blot, a densitograph was built by digital image analysis, and subsequently a multivariate discriminate analysis was performed. Results: A complex staining pattern was found in the tears of both dry-eye patients and healthy controls. However, the number of peaks was statistically significantly increased (p < 0.05) in the tears of dry-eye patients. The discriminant analysis found a statistically significant difference between the antibody repertoires of both groups (Wilks' lambda = 0.11; p < 0.001). Conclusions: In this study, it could be shown that the complex antibody repertoires in the tears of patients suffering from dry-eye disease are different from those found in the tears of healthy volunteers. Thus, our findings support the hypothesis that the dry eye disease has an autoimmune mechanism. Copyright (C) 2001 S. Karger AG, Basel.