Abstract
Abstract: :
Purpose: Corneal transparency recovers following corneal allograft rejection in the rat, possibly due to endothelial proliferation and migration of recipient endothelium and/or proliferation or not of surviving donor endothelium. To further elucidate this we have developed a method of labelling donor corneal endothelial cells that can be used to observe their fate in vivo. Methods: Immersion of tissue in PKH26, an aliphatic fluorescent chromophore, was used to label membranes of corneal endothelial cells in vitro. Staining and concentration protocols were optimised as assessed by confocal microscopy. The fate of labelled endothelial cells was then observed following corneal allo- and iso-transplantation on day 10 (pre-rejection), day 15 (rejection) and day 25 (resolution and re-establishment of corneal clarity) post-transplant. Results: In vitro endothelial cell labelling was maintained for at least 10 days. After corneal transplantation there was a progressive loss of labelled endothelial cells compared to in vitro correlate. By day 10 post-transplant there was no difference in extent or intensity of labelled endothelium between iso- and allografts. Cell labelling was observed up to day 25 post-transplant and the intensity and extent of labelling was more in isografts. Where labelling persisted in allografts it was observed in less than 5% of cells. Conclusions: The technique describes a modified in vitro labelling of donor endothelial cells, which can be used successfully to observe their fate following surgery.
Keywords: cornea: endothelium • microscopy: confocal/tunneling • microscopy: light/fluorescence/immunohistochem