Objective: To investigate the feasibility of using amniotic membrane (AM) as a carrier for cultured corneal endothelial cells transplantation.
Methods: Rabbit corneal endothelial cells were cultivated, passaged, and labeled with the fluorescent tracker CM-DiI, then transplanted onto denuded AM. The cell density, morphology, histology and ultrastructure of the cultured cells on AM were examined by light microscope, fluorescent microscopy and scanning electron microscope. To determine whether these composite endothelial sheets were functional in vivo, the sheets were transplanted onto rabbit corneas whose deep lamellar with Descemet's membrane and endothelial cells had been completely removed. The deep layer excised rabbit corneas without any transplantation or with transplantation of denuded AM were treated as controls. After transplantation, the corneal appearance and corneal thickness were examined. The grafts were examined for cell density, morphology and histology 4 weeks after the surgery.
Results: A monolayer of endothelial cells were confluent on the AM 5 - 7 days after seeding. The density of the endothelial cells was (3202.84 +/- 347.77)/mm(2). Morphologically, the sheets consisted of a fairly continuous layer of flat polygonal endothelial cells that appeared uniform in size with tight junctions. The labeled cells were red in color under fluorescent microscopy. After transplantation, the corneas that received cultured endothelial cells had little edema and retained their thinness and transparency, while the corneas of controls showed prominent edema and opacity, indicating that these cells were transplanted cells rather than the cells migrated from peripheral cornea. Four weeks after surgery, the labeled endothelial cells were still found in the cornea with red fluorescence.
Conclusions: AM maintains cultured endothelial cells' morphology and function both in vitro and in vivo. AM could serve as a carrier for corneal endothelial cells transplantation. These results provide a promising method for the treatment of diseases caused by corneal endothelial disorders.