Morphological changes of human pulmonary-artery endothelial cells after 12-hours hypothermic storage in organ-preservation solutions

Pulmonary endothelial cells are known to be fundamental for lung preservation and one of the most serious limiting factors observed during transplantation is the stress to which these cells are subjected. On this premise, strenuous efforts should be made to select and employ the preservation solution best able to prolong ischemia time and thus prevent cytotoxic effects. The aim of this study was to identify the solution with minimum toxicity on endothelial cells. For this purpose, we analysed the noxious effect of solutions such as Euro Collins (ECS), Belzer (UWS) and Low-potassium Dextran (LPD) on endothelial cells after 12 hours of incubation at 10°C. For each solution, we examined the modifications produced on the nuclei, mitochondria and cellular wall of human pulmonary-artery endothelial cells by transmission electron microscopy and recorded the results on an ultrastructural grading scale. As regards morphological alterations incompatible with cell life, the most cytotoxic solution proved to be ECS. UWS and LPD, on the contrary, appeared to preserve cells relatively well, and no perceptible difference was observed between the two solutions. In conclusion, it is interesting to note that although ECS is widely used for lung preservation, the results of our study indicate that a 12 hours at 10°C in this solution may exert adverse effect on pulmonary endothelial cells.