Conjunctival transplantation. Autologous and homologous grafts

Autologous conjunctival transplants have been used successfully for restoration of damaged ocular surfaces. Homologous (allogeneic) conjunctival grafts have been explored less systematically. We developed a nonhuman primate model for comparison of autologous and homologous conjunctival transplantation in order to assess the clinical viability and immunopathologic characteristics of these grafts. Autologous or homologous grafts were performed in nine adult rhesus monkeys. Both autologous and homologous grafts were compared for clinical viability and immunopathologic change. Clinical results suggest that, although homologous grafts incited a greater inflammatory and scarring response, there was minimal graft shrinkage and a normal surface epithelium. Immunopathologic studies using laminin, bullous pemphigoid antigen, and fibronectin indicate that, despite the increased inflammatory response seen in homografts, the epithelial surface is normal. With our increasing ability to modulate the immune response, conjunctival homografts may play a role in restoration of the ocular surface.