Ex-Situ Normothermic Split Liver Machine Perfusion: Protocol for Robust
Comparative Controls in Liver Function Assessment suitable for the
evaluation of novel therapeutic interventions in the pre-clinical
setting.
Abstract
Background: Ex-situ donor liver machine perfusion is a promising tool to
assess organ viability prior to transplantation and a platform to
investigate novel therapeutic interventions. However, the wide
variability in donor and graft characteristics between individual donor
livers limits the comparability of results. We investigated the
hypothesis that the development of a split liver ex-situ machine
perfusion protocol provides the ideal comparative controls in the
investigation of machine perfusion techniques and therapeutic
interventions, thus leading to more comparable results. Methods: Four
discarded human donor livers were surgically split following
identification and separation of right and left inflow and outflow
vessels. Each lobe, on separate perfusion machines, was subjected to
normothermic perfusion using an artificial haemoglobin-based oxygen
carrier solution for six hours. Metabolic parameters as well as hepatic
artery and portal vein perfusion parameters monitored. Results: Trends
in hepatic and portal vein flows showed a general increase in both lobes
throughout each perfusion experiment, even when normalised for tissue
weight. Progressive decreases in perfusate lactate and glucose levels
exhibited comparable trends in between lobes. Conclusion: Our results
demonstrate comparability between right and left lobes when
simultaneously subjected to normothermic machine perfusion. In the
pre-clinical setting, this model provides the ideal comparative controls
in the investigation of therapeutic interventions for GMP cellular
therapies.