The ultimate objective of our proposed research is to assess the role of complement in external diseases of the eye. Functional complement activity in guinea pig corneas and human corneas and aqueous humor will be determined using 50% hemolysis (CH50) of sensitized sheep red blood cells. Hemolytic complement activity in normal human and guinea pig corneas will be compared with pathological specimens to determine if complement levels fluctuate in corneal diseases. In addition, hemolytic activity in human primary aqueous will be compared with hemolytic complement in secondary aqueous humor to determine if complement levels are altered with various types and degrees of intraocular inflammation. Chemotaxis under agarose is a new and simple method that we propose to use for studying chemotactic relationships in the cornea in vitro. The migration of neutrophils to corneal eluate and corneal eluate mixed with various activators and inhibitors of the classical and alternative complement pathways can be assessed using corneal tissue and neutrophils from rabbits or human. We will determine if corneal fibroblasts have the capacity to produce Clq and C3 like other fibroblast cell lines and if they are a possible source of these complement components. The media from corneal fibroblasts in tissue culture will be collected and reacted against antisera to human C3 and Clq in gel double diffusion experiments and will be assayed for C3 hemolytic complement activity. Langerhans cells of the epidermis have been shown to carry Fc and C3 receptors and have been theorized to represent the most peripheral outpost of the afferent limb of the immune system. Langerhans-like cells have been described in the corneal epithelium and conjunctival epithelium at the limbus and will be investigated for the presence of these Fc and C3 receptors by rosette formation with sheep red blood cells coated with IgG or complement. We will continue our direct immunofluorescent studies of immunoglobulin and complement deposition in human corneal tissue obtained at keratoplasty and in the rabbit model that we have developed for the catarrhal and phlyctenular lesions of the human cornea related to staphylococci.