Abstract
Abstract: :
Purpose: Aquaporin 5 (AQP5), which is a selective water channel, is highly expressed in lacrimal and salivary glands. The purpose of this study was to evaluate whether the measurement of AQP5 protein content in tear fluid was the optical parameter for Sjogren's Syndrome. Methods: Basal tears were collected from the inferior marginal tear strip of patients with a calibrated capillary tube. The concentration of AQP5 protein was measured by originated human AQP5 ELISA procedure. In this system, human AQP5 was detected by using an affinity-purified antibody to the C-terminus of human AQP5. Results: Quantification of AQP5 protein by ELISA were 38.8 pg/µl in normal controls (n=6), 51.9 pg/µl in non-Sjogren's Syndrome dry eye (n=79), and 116.5 pg/µl in Sjogren's Syndrome patients (n=28). Conclusion: The measurement of AQP5 in tear fluid can be used for diagnosis of Sjogren's Syndrome. These results support the hypothesis that AQP5 protein is leaked into tear fluid when the lacrimal glands are damaged by lymphocytic infiltration in Sjogren's Syndrome.
Keywords: 376 cornea: tears/tear film/dry eye • 324 aqueous • 452 lacrimal gland