[Experimental study on corneal organ culture preservation and its application]

Abstract

Objective: To develop a optimal method of corneal organ culture preservation, to evaluate the characteristics of organ cultured cornea and to examine the feasibility of application of organ cultured corneas.

Methods: Thirty-six adult New Zealand rabbit corneas were stored in the closed storage system consisting of fetal calf serum and were transferred to a hyperosmosis dextran-containing medium for 48 hours' deswelling for further experiment after storage for 1, 2, 3 and 4 weeks. The measurement of corneal endothelium density and central thickness was performed prior to and after the storage. The morphology and the contamination of preserved cornea, as well as allogenic grafts' conditions within 7 days after corneal transplantation were also observed. The class II MHC antigen immunofluorescence marker was performed for the examination of corneal dendritic cells by confocal microscopy.

Results: The corneal organ culture preservation was successfully established. The contamination rate was approximately 8.3%. All of the rabbit corneas stored within 4 weeks remained transparent. There were little folds in peripheral descemet's membrane when the storage time was up to 3 weeks and the whole descemet's membrane folds was seen when the corneas had been preserved for 4 weeks. The density of corneal endothelium decreased when the preservation time was extended. The loss of corneal endothelium preserved up to 4 weeks was 15.7%. Correlation existed between the thickness of center cornea and the preservation time. The average central thickness of the cornea was 0.7 mm after 4 weeks. The light micrographs showed that the endothelium layer still covered the descemet's membrane completely after 4 weeks. The dendritic cells resided in the limbus epithelium and they were lost after stored for 3 weeks. After allogenic corneal transplantation, the grafts retained transparency within 7 days postoperatively, which indicated that there was no primary failure of grafts.

Conclusion: Corneal organ culture preservation can ensure the normal function of cultured cornea within a certain preservation time and offer some advantages, e.g. the decrease of corneal immunogenicity.