Conjunctival structural and functional reconstruction using acellular bovine pericardium graft (Normal GEN®) in rabbits.

Abstract

To evaluate the effectiveness of acellular bovine pericardium grafts (Normal GEN®) used as scaffolds for conjunctival reconstruction. The acellular bovine pericardium graft and the amnion graft were implanted into the bulbar conjunctival defects of adult rabbits. Conjunctival samples of implanted materials and blank defect controls were observed at day 3, 7, 14, 21, 28, and 56 postoperatively. Histological examination was observed at day 14, 28, and 56 of surgery, including hematoxylin-eosin staining, periodic acid-Schiff staining, and Masson's trichrome staining, while immunofluorescent microscopy was observed at 14days and 28days after surgery. Results were compared among the Normal GEN®, amnion, and blank defect controls. All three groups showed complete conjunctival reconstruction. Wounds that were not grafted closed by formation of conjunctival scar characterized by a linear array of densely packed collagen fibers in Tenon's capsule. Subepithelial tissue in the grafted groups comprised a loosely organized network of randomly oriented collagen that resembled that of the normal bulbar conjunctiva. However, there was a dense layer of aligned collagen between the conjunctival Tenon's capsule and the sclera in the NormalGEN® group, about 250μm in thickness. Implantation of the NormalGEN® graft promoted the formation of conjunctiva as a kind of scaffold both in structure and in function. It had more advantageous mechanical properties than the amnion, strong and elastic, during the period of conjunctival reconstruction.