International Sicca Award

- Edition 2005 -

Future Research Projects Germany

Dr. med. Focke Ziemssen, MD
University Eye Hospital, Department l, Tubingen

Sicca-prophylaxis: increase in blinking activity by visual animation signals during visual display terminal work (biofeedback for blinking and therapy with lubricants)

Abstract
Growing impact of computer work has lead to a marked increase in complaints associated with dry eye disease. Significant reduction of blinking during activity with attention- or concentration-demanding character, e. g. during visual display terminal (VDT) work, is a main reason resulting in evaporation of the anterior eye environment. All previous approaches did not take into account these mechanic factors of tear-film reconstitution and individual differences of complex blinking behaviour.
Development of a mobile and non-invasive analysis system for detection of lid movements enables the assessment of the blinking activity during VDT work. Standardized measurement of other objective parameters (Schirmer-test, Jones-test, break-up time, staining with fluorescein and rose bengal dye, video-topography) and subjective complaints (questionnaire) makes it possible to define an individual risk profile.
Influencing of blinking by individually adjusted reinforcement (biofeedback) was tested in over 50 computer workers. So far, we could show that animation does make blinking more frequent and can result in homogeneous and more regular blinking patterns. Questions about the individual frequency to be aimed at, the optimal application rhythm and the acceptance in longer use still have to be answered. Although the therapeutic benefit is not proven in a blinded and controlled field study yet, there are good reasons to assume that an increase in the windshield- and lubricant-effect of blinking will also improve the surface protection.

The external signals could also be used to remind the additional application of viscoelastic agents or lubricants by a personal computer and promise a comprehensive change in the perception and awareness of the persons with dry eye disease.

Dr. rer. nat. Kristin Recker, Prof. Dr. Friedrich Paulsen
Faculty of Medicine, Department of Anatomy and Cell Biology, Halle (Saale)

The role of the yMransporter in the pathogenesis of keratoconjunctivitis sicca

Abstract
Keratoconjunctivitis sicca is a chronic, bilateral desiccation of the conjunctiva and cornea due to inadequate tear volume or to excessive loss of tears due to accelerated evaporation because of poor tear quality. The symptoms induce damage of the eye surface and indisposition.
Nearly all of 5 patients are affected, who goes to an ophthalmologist. Although the aetiology and pathology are investigated, many questions are unanswered. The following experiments should analysed the most important cationic amino acid transporter in the mammalian cells, the y*-system, in tissue of the eye surface. The y*-system transport the substrate of the nitric oxide syntha-se (NOS), l-arginine. The NOS and her product NO play an important role in many inflammatory processes. Referring to this no results are given for the eye surface.

Dr. med. Heinrich Heimann, K. Hohne1, S. E. Coupland

Characterisation of immune competent cells in the conjunctiva of patients with diabetes mellitus

Abstract
Background: Patients with diabetes mellitus have an increased frequency of dry-eye symptoms. The morphological changes of "diabetic conjunctiva" include squa-mous metaplasia and goblet cell loss; these alterations are reported to correlate with the blood-sugar levels and the severity of peripheral polyneuropathy. Furthermore, changes of the conjunctival microcirculation of diabetic patients have been described. Latest reports suggest that the pathogenesis of the above-mentioned alterations is an immunomodulatory inflammatory one, possibly initiated by autoantigens, which are localized in the lacrimal gland or in the layers of the ocular surface.
Methods: In the proposed research project, conjunctival biopsies of patients with diabetes mellitus will be compared with a non-diabetic control group. These biopsies will be obtained on opening of the conjunctiva during standard pars plana vitrectomies. These specimens will be fixed in formalin, and examined using both conventional histological and immunohistological methods. These investigations will aim at characterizing the lymphocytic populations (CD4 versus CDS), possibly with demonstration of the transcription factor T-bet in the T- and/or B-cell populations. Further the expression of the B-cell antigen BAFF in the cellular infiltrates will be analysed. The aim of the examinations is determine if there is any correlation between the density of the in-flammtion, and the presence of- and degree of dry eye symptoms in diabetic patients.

Dr. med. Sonja Werwitzke, PhD Dr. med. Torsten Witte
Department of Clinical Immunology, Medical School, Hannover

CMV replication in Sjogren's syndrome

Abstract
Sjogren's syndrome is a common autoimmune disorder of unknown etiology. Family and twin studies have revealed a contribution of genetic risk factors to its etiology. Furthermore, chronic viral infections, such as cytomegalovirus (CMV) infection, may trigger the disease. The immune response against cytomegalovirus is genetically determined. Peptides encoded by CMV are presented by infected cells on the receptor MIC-A and are recognized by T and NK cells via the receptor NKG2D. As a consequence, those cells get activated and lyse the infected cells.
In prior studies supported by the "Arbeitsgruppe Trockenes Auge" an association of Sjogren's syndrome with alleles of the receptors MIC-A and NKG2D was revealed. Both alleles are associated with a reduction of recognition of CMV infected cells by T cells.
In the project proposed now we want to study, whether replication of CMV in peripheral blood of patient may trigger Sjogren's syndrome. Therefore, we want to compare replication of CMV in blood of patients with Sjogren's syndrome in remission and in active disease and of blood donors using a sensitive quantitative PCR.

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