At the First International Meeting on Ischemia Reperfusion Injuries in Transplantation (IMIRT) held in Poitiers, France from May 3–4, Organ Recovery Systems was delighted to sponsor an educational symposium titled: Functional mechanisms of hypothermic machine perfusion.
Chairing the symposium was Professor Benoît Barrou of the Pitié Salpétriêre Hospital, Paris, France, who opened the meeting by introducing data from the landmark Machine Preservation Trial,1 the results of the 3-year follow-up study2 and data from the ECD subset.3
Dr Mike Taylor, Vice President at Cell and Tissue Systems, Inc., Adjunct Professor of Mechanical Engineering at Carnegie Mellon University, Pittsburgh, USA and Adjunct Professor of Surgery at Drexel University, Pittsburgh, USA, followed this presentation by providing a review of the evolution of and key principles underpinning hypothermic organ preservation. Dr Taylor reported on how the proven protective properties of hypothermia are being used for organ preservation today and how the potential benefits might be harnessed for future preservation modalities.4 He illustrated this point by citing the recent clinical study using hypothermic machine perfusion in liver transplantation and by discussing how protection might be given to the use of marginal organs through adding protective agents to perfusate. Whilst controlling the environment of the cell and selecting the optimum solution design are critical, Dr Taylor also concluded that there is a need to standardize and control the technical parameters impacting organ viability to minimize ischemic change induced by hypothermia. For example, with the use of machine perfusion it is important to be able to deliver perfusate without barotrauma or microvascular stress.
Dr Stefan G. Tullius, Chief of Transplant Surgery at Brigham and Women's Hospital and Associate Professor of Surgery at Harvard Medical School, Boston, USA, presented on potential mechanisms of endothelial protection resulting from machine perfusion in a transplant organ. Amongst these proposed mechanisms of endothelial protection, Dr Tullius highlighted the potential role played by KLF2, a novel transcriptional regulator of endothelial activation, noting that KLF2 expression in the endothelium is rapidly lost upon the cessation of flow, therefore leading to potential endothelial damage in its absence. His work suggests that machine perfusion simulates physiological conditions which maintain endothelial integrity, thus preventing endothelial damage and subsequent inflammatory responses.
In a stimulating final presentation, Professor Diethard Monbaliu, from University Hospitals Leuven, Belgium, presented on the physics underpinning renal resistance values and their potential prognostic application. His presentation spanned the history of machine perfusion, along with an overview of the prognostic potential of renal resistance as applied to the Machine Preservation Trial.5 Professor Monbaliu concluded that renal resistance is an important additional and objective tool for graft quality assessment, although it should not be used alone to decide whether or not to discard a donor kidney.
1. Moers C, et al. Machine Perfusion or Cold Storage in Deceased-Donor Kidney Transplantation.
N Engl J Med 2009;360:7–19.
2. Moers C, et al. Machine Perfusion or Cold Storage in Deceased-Donor Kidney Transplantation.
N Engl J Med 2012;366:770–1.
3. Treckmann J, et al. Machine perfusion versus cold storage for preservation of kidneys from expanded criteria donors after brain death. Transpl Int 2011;24:548–54.
4. Taylor MJ, et al. Current state of hypothermic machine perfusion preservation of organs: The clinical perspective. Cryobiology. 2010;60:S20–35.
5. Jochmans I, et al. The prognostic value of renal resistance during hypothermic machine perfusion of deceased donor kidneys. Am J Transplant 2011;11:2214–20.