A new preservation system that pumps cooled, oxygen-rich fluid into donor livers not only keeps the organs in excellent condition for as long as nine hours before transplantation, but also leads to dramatically better liver function and increases survival of recipients, according to a series of animal studies by researchers at the University of Pittsburgh School of Medicine and the McGowan Institute for Regenerative Medicine. The system could be tested with transplant patients at UPMC later this year.
The findings, which were published online in the American Journal of Transplantation, suggest that it's possible to use the technique of "machine perfusion" with a newly created cell-free oxygenated solution to expand the number of high-quality livers available for transplant, thereby shortening waiting times and reducing patient mortality.
Currently, 20 to 40 percent of donor livers cannot be transplanted into recipients because oxygen deprivation during storage and transport in conventional containers can make pre-existing tissue damage worse, explained senior investigator Paulo Fontes, M.D., UPMC transplant surgeon, associate professor, Starzl Transplantation Institute, Department of Surgery, Pitt School of Medicine, and a deputy director of the McGowan Institute. If the damage is too extensive, the organ cannot be safely transplanted into a patient.
"Standard practice is to use a method called cold static preservation, which uses tissue cooling to slow down metabolism with the aim of reducing the demand for oxygen and thus protecting cells from death," Dr. Fontes explained. "In our new system, we pump a special fluid designed to deliver oxygen to the liver, creating an environment that supports normal function. The integrity of the cells and vital metabolic activity is sustained for eventual transplantation of the organ."
The research team optimized a machine-perfusion (MP) device that was developed by Organ Assist, a company in the Netherlands, and added a fluid with a hemoglobin-oxygen carrier component to deliver high concentrations of oxygen to the tissue. The liver is immersed in chilled fluid, which is also pumped through tubes inserted into the organ's large blood vessels to effectively oxygenate the tissue.
The team transplanted six pigs with livers that had been kept for nine hours, roughly the average time between recovery of the organ and transplantation into a recipient, in the MP system and another six with organs placed in the standard container.
They found that 100 percent of the pigs who got MP livers survived, compared to 33 percent of those who received conventionally preserved organs. The MP livers functioned better, produced more bile and had higher oxygen levels than their conventional counterparts, and analyses of multiple biomarkers including inflammatory mediators indicated that the MP livers had been better preserved.
Also, "it was immediately obvious to us that the pigs who received MP livers looked much healthier and easily moved around their pens just hours after they woke up from the surgery," Dr. Fontes said. "They didn't look as ill as the animals treated with standard cold preservation. It was amazing."
The data from the studies have been shared with federal regulators, he added, with the aim of launching a clinical trial to test the system at UPMC this year.
"This system has great potential to enhance our current standards for organ preservation, which should translate into more patients getting a life-saving procedure with potentially better outcomes," Dr. Fontes said. "Not only that, we have hopes of a faster recovery because the liver could be less likely to become injured due to a lack of oxygen."
Co-investigators include Roberto Lopez, M.D., Yoram Vodovotz, Ph.D., Marta Minervini, Ph.D., Victor Scott, M.D., Kyle Soltys, M,D., Sruti Shiva, Ph.D., Shirish Paranjpe, Ph.D., David Sadowsky, Derek Barclay, Ruben Zamora, Ph.D., Donna Stolz, Ph.D., Anthony Demetris, M.D., George Michalopoulos, M.D., Ph.D., and James Wallis Marsh, M.D., all of the University of Pittsburgh; and Arjan van der Plaats, Ph.D., of Organ Assist, Groningen, Netherlands.
The study was funded by a charitable gift from Mr. and Mrs. Garcia de Souza, as well as grant DK072146 from the National Institutes of Health.
About the University of Pittsburgh School of Medicine
As one of the nation's leading academic centers for biomedical research, the University of Pittsburgh School of Medicine integrates advanced technology with basic science across a broad range of disciplines in a continuous quest to harness the power of new knowledge and improve the human condition. Driven mainly by the School of Medicine and its affiliates, Pitt has ranked among the top 10 recipients of funding from the National Institutes of Health since 1998. In rankings recently released by the National Science Foundation, Pitt ranked fifth among all American universities in total federal science and engineering research and development support.
Likewise, the School of Medicine is equally committed to advancing the quality and strength of its medical and graduate education programs, for which it is recognized as an innovative leader, and to training highly skilled, compassionate clinicians and creative scientists well-equipped to engage in world-class research. The School of Medicine is the academic partner of UPMC, which has collaborated with the University to raise the standard of medical excellence in Pittsburgh and to position health care as a driving force behind the region's economy. For more information about the School of Medicine, see http://www.
Contact: Anita Srikameswaran
Contact: Jennifer Yates
Anita Srikameswaran | EurekAlert!
Virtual Reality in Medicine: New Opportunities for Diagnostics and Surgical Planning
07.12.2016 | Universität Basel
3-D printed kidney phantoms aid nuclear medicine dosing calibration
06.12.2016 | Society of Nuclear Medicine
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Life Sciences
08.12.2016 | Physics and Astronomy
08.12.2016 | Materials Sciences