We propose to prepare transparent, polymeric membranes, primarily of collagen and/or glycosaminoglycans, and to evaluate these materials with regard to the following in vitro properties: (a) their ability to support surface cell growth and adhesion, (b) their strength and elasticity, and (c) their optical properties (i.e., transparency). The overall objective of this project is the production of a biopolymeric material suitable for use as a perforating keratoprosthesis. To this end, we will evaluate promising materials in vivo in experimental animals with regard to (a) the degree to which they induce corneal inflammation, (b) their ability to support the ingrowth of fibroblasts (i.e., heal) and the regeneration of surface epithelium, (c) their ability to resist enzymatic degradation, (d) their ability to resist the stresses to which they would be subjected in the anterior segment of the eye, and (c) their ability to remain transparent for an extended period while functioning as a penetrating corneal graft. Successful completion of our experimental goals will result in the production of a prosthetic membrane, composed largely of biopolymeric materials, that would be suitable for use as a replacement for an opaque cornea. This would have considerable impact on the clinical treatment of corneal disease, the world's leading cause of blindness.