An Experimental Investigation Of The Function Of Basic Fibroblast Growth Factor(bFGF) On Corneas In The Mid-Term Preserved Medium In Vitrio

Objective We investigated the function of bFGF on corneas in the mid-term preserved medium in vitro, in order to provide theoretical basis for improving the medium of corneal mid-term preservation. Methods We prepared the modified McCarey-Kaufman medium (mM-K) which contained minimum essential medium (MEM) , dextran (40000) , HEPES , and so on . Corneas of New Zealand's white rabbits were preserved in mM-K medium and mM-K medium with bFGF (10ng/ml) at 30~34℃ (Celsius degree) for 16~18 hours , after that transmited them to 4℃ to be preserved . Viability study of corneal endothelial cells (CEC) was performed by trypan blue-alizarin red staining under light microscope. Morphological study was performed by light microscpe, scanning electron microscope and transmission electron microscope on the occurrences of apoptosis and proliferation at 3, 5, 7 days after the corneas had been preserved in the two kinds of media. Quantitative study was also performed on the occurrences of apoptosis by TUNEL under immunofluroscent microscope and proliferating cells by PCNA under light microscope at different time . Results Edema , folds of preserved corneas are slight in bFGF group . The corneas, transparency, cell s, shape and the cell s, viability of corneas preserved in mM-K medium with bFGF are better than that in mM-K medium . The characteristic apoptotic cells were observed by immunofluroscent microscope and electron microscope in corneal epithelium , stroma and endothelium when corneas were preserved in two kinds of media after 3 ,5 ,7 days .TUNEL-positive cells increased evidently when prolonged the time of corneal preservation in two kinds of media (p <0.01) . TUNEL-positive cells of corneas in mM-K medium were singnificantly higher than that in bFGF medium ( p<0.01) ; PCNA-positive cells in bFGF medium were significantly higher than that in mM-K medium ( p<0.01) .Conclusions The results indicated that apoptosis occurred in mid-term preservation and apoptosis influences the integrity and the function of the preserved corneas . mM-K medium with added bFGF has significant difference in inhibiting the apoptosis and stimulating cells proliferation in mid-term preserved corneas . We can apply bFGF to corneal mid-term preservation .