My ultimate goal for the mentored clinical scientist development award is to acquire expertise in the field of innate immunity. Specifically, I will investigate the role of Fas Ligand (FasL) in regulating neutrophil-mediated (innate immunity) inflammation in the cornea. The combination of this training with my previous research experience in adaptive immunity will give me the opportunity to develop a comprehensive research program to study corneal immunology. The Cole Eye Institute and the Immunology Department at the Cleveland Clinic Foundation provide the clinical and basic science support necessary to allow the development of clinical scientists and the unique opportunity to practice translational medicine. Overall, the training environment, at this institution will provide me with both the technical and intellectual tools necessary to become a successful investigator in vision research. My long-term career goal is to establish a comprehensive and independent research program dedicated to dissect the regulatory immune mechanism used by the cornea to control inflammation. Scientific findings generated form this research will be used to development target-specific immunotherapies for the treatment of destructive inflammatory diseases of the cornea. The objective of this project is to test the novel hypothesis that the forms of FasL expressed in the cornea are a key factor in the differential regulation of inflammation: soluble FasL blocks and membrane FasL induces keratitis. Preliminary data demonstrate that soluble FasL is anti-inflammatory by inhibiting neutrophil activation, while membrane FasL activates them and is pro-inflammatory. The proposed studies will implement a novel method of in vivo transfection of corneal stromal cells using adenoviral vectors to express soluble and membrane FasL in the cornea and determine the biological regulation of neutrophil activation in corneal tissue. In vitro experiments using isolated neutrophils and cells lines transfected with membrane and soluble FasL will complement these studies and will facilitate the dissection of cellular and molecular signals differentially regulated by these molecules. Moreover, we will use the in vivo transfection technique to determine the role of soluble Fas L in the down-regulation and prevention of neutrophil-mediated ocular damage in a model of lipopolysaccharide induced keratitis that has clinical implications. We anticipate that these studies will yield new information about the regulation of ocular inflammation by FasL and lead to the development of new treatments using soluble FasL to treat and prevent neutrophil-mediated ocular damage.