IN-VITRO EVALUATION OF DONOR LIVER PRESERVATION FLUIDS ON HUMAN HEPATOCYTE FUNCTION

Successful liver transplantation depends on adequate preservation of c ellular function. We therefore tested the effects of two currently use d liver preservation fluids, Euro-Collins (EC) solution and University of Wisconsin (UW) solution, on the viability and some functional acti vities of hepatocytes isolated from human livers. Cells in primary cul ture were maintained under hypoxic (95% N-2/5% CO2) and hypothermic (4 degrees C) conditions for 24 h, either in EC or UW solution. This tre atment did not result in significant hepatocyte damage, as judged by p hase contrast microscopy, intracellular LDH release, and the MTT mitoc hondrial test. However, neutral red uptake indicated that lysosomal fu nctions were slightly affected (35% decrease) when compared to control conditions. At the end of the hypoxia/hypothermia period, hepatocyte monolayers were incubated at 37 degrees C under normoxic conditions fo r 24 h, in order to simulate the reperfusion of a transplanted liver. Three drugs - midazolam, diazepam, zidovudine - were used as diagnosti c substrates to check the metabolic abilities of human hepatocytes rep laced in normal conditions. Both phase I (hydroxylation, demethylation ) and phase II (glucuronidation) metabolic reactions were affected by the hypoxia/hypothermia shock. Indeed, a 30%-50% decrease in these act ivities was observed as compared to values obtained in control hepatoc ytes. No difference could, however, be found at the cellular level reg arding the solution used for cold storage. These results suggest that the superiority of UW over EC solution, already reported in clinical p ractice after transplantation of preserved human livers, was not due t o a better preservation of the hepatocytes.