Ocular Immunology

Allergic eye disease, in some form, affects greater than 20 million people in the United States. To date, no systematic investigation has been undertaken to understand the molecular signaling events on the ocular surface of patients undergoing allergic reactions, or to explain the mechanism of cellular infiltration in allergic eye disease patients.

Research by Dr. Neil Barney is designed to determine if activated human conjunctival mast cells will supply sufficient cytokines and other mediators to initiate and direct a well-orchestrated trafficking of eosinophils and other inflammatory cells to the ocular surface, facilitate their adhesion, and cause their release of potent effectors of ocular surface damage.

Dr. Barney's lab also hopes to determine the differences in molecular signaling in patients undergoing seasonal allergic conjunctivitis compared to those with sight threatening disease, such as atopic keratoconjunctivitis.

They use methods that include activation with anti-IgE or secretagogue of human conjunctival mast cells. Evaluation of the levels of cytokines released is by ELISA, micro bead assay, or by examining the RNA by RT-PCR. Following treatment with activated supernatants from conjunctival mast cells, human conjunctival and corneal epithelial cells are then evaluated by FACS, RT-PCR, and ELISA for production of cell adhesion molecules and eosinophil-attracting chemokines. Eosinophil adhesion to these stimulated epithelial cells will be measured by eosinophil peroxidase adhesion assays. Eosinophils, following attachment to these epithelial cells, will be evaluated for activation by evaluation of oxidative burst, and release of potent effectors of epithelial cell damage, such as eosinophil cationic protein.

These in-vitro results guide in-vivo evaluation of ocular surface cells, which are obtained by impression cytology from patients undergoing an allergic reactions induced by topical provocation with allergen.