Yale scientists restore cell and organ function in pigs after death

Organ perfusion and cell recovery with OrganEx technology

Illustration of organ perfusion and cell recovery with OrganEx technology. The cell-saving blood analog is delivered to vital organs within an hour of death. Credit: Marin Balaic

The Yale-developed technology restores cell and organ function in pigs after death, a potential advance in organ transplantation.

Within minutes of the heart’s last beat, a cascade of biochemical events triggered by a lack of blood flow, nutrients, and oxygen begins to destroy the body’s cells and organs. However, a team of researchers from[{” attribute=””>Yale University has discovered that massive and permanent cellular failure doesn’t have to happen so quickly.

Using a new technology the scientists developed that delivers a specially designed cell-protective fluid to organs and tissues, the team restored blood circulation and other cellular functions in pigs a full hour after their deaths. They report their findings in the August 3 edition of the journal Nature.

Their results may help extend the health of human organs during surgery and expand the availability of donor organs, the authors said.

All cells do not die immediately, there is a more protracted series of events,” said David Andrijevic, associate research scientist in neuroscience at Yale School of Medicine and co-lead author of the study. “It is a process in which you can intervene, stop, and restore some cellular function.”

The research builds upon an earlier Yale-led project that restored circulation and certain cellular functions in the brain of a dead pig with technology dubbed BrainEx. Published in 2019, that study and the new one were led by the lab of Yale’s Nenad Sestan, the Harvey and Kate Cushing Professor of Neuroscience and professor of comparative medicine, genetics, and psychiatry. The new study involved senior author Sestan and colleagues Andrijevic, Zvonimir Vrselja, Taras Lysyy, and Shupei Zhang, all from Yale.

If we were able to restore certain cellular functions in the dead brain, an organ known to be most susceptible to ischemia [inadequate blood supply]we hypothesized that something similar could be achieved in other vital transplantable organs as well,” Sestan said.

In the new study, the scientists applied a modified version of BrainEx called OrganEx to the entire pig. The technology consists of a perfusion device similar to cardiopulmonary bypass machines, which do the work of the heart and lungs during surgery, and an experimental fluid containing compounds that can promote cellular health and suppress inflammation throughout the body. of the pig. Cardiac arrest was induced in anesthetized pigs, which were treated with OrganEx one hour after death.

Six hours after OrganEx treatment, the researchers found that certain key cellular functions were active in many areas of the pigs’ bodies, including the heart, liver and kidneys. In addition, some organ functions had been restored. For example, they found evidence of electrical activity in the heart, which retained the ability to contract.

We were also able to restore circulation throughout the body, which amazed us,” said Sestan.

Normally, when the heart stops beating, the organs begin to swell, collapsing blood vessels and blocking circulation, he said. However, circulation was restored and the organs of the deceased pigs that received the OrganEx treatment appeared functional at the cell and tissue level.

Under the microscope, it was difficult to differentiate between a healthy organ and one that had been treated with OrganEx technology after death,” said Vrselja.

As in the 2019 experiment, the scientists also found that cellular activity in some areas of the brain had been restored. However, no organized electrical activity indicating consciousness was detected during any part of the experiment.

The team was especially surprised to observe spontaneous and involuntary muscle movements in the head and neck areas when they tested the treated animals, which remained anesthetized throughout the six-hour experiment. These movements indicate the preservation of some motor functions, Sestan said.

Additional studies are needed to understand the apparently restored motor functions in the animals, the researchers stressed. They also called for rigorous ethical review by other scientists and bioethicists.

The experimental protocols for the latest study were approved by the Yale Institutional Animal Care and Use Committee and guided by an external advisory and ethics committee.

The OrganEx technology could eventually have several potential applications, the researchers said. For example, it could extend the lifespan of organs in human patients and expand the availability of donor organs for transplantation. It might also help treat organs or tissues damaged by ischemia during heart attacks or strokes.

There are numerous potential applications of this exciting new technology,” said Stephen Latham, director of the Yale Interdisciplinary Center for Bioethics. “However, we must maintain careful oversight of all future studies, particularly any involving brain perfusion.”

Reference: “Cellular Recovery After Prolonged Warm Ischemia of the Whole Body” by David Andrijevic, Zvonimir Vrselja, Taras Lysyy, Shupei Zhang, Mario Skarica, Ana Spajic, David Dellal, Stephanie L. Thorn, Robert B. Duckrow, Shaojie Ma , Phan Q. Duy, Atagun U. Isiktas, Dan Liang, Mingfeng Li, Suel-Kee Kim, Stefano G. Daniele, Khadija Banu, Sudhir Perincheri, Madhav C. Menon, Anita Huttner, Kevin N. Sheth, Kevin T. Gobeske , Gregory T. Tietjen, Hitten P. Zaveri, Stephen R. Latham, Albert J. Sinusas, and Nenad Sestan, August 3, 2022, Nature.
DOI: 10.1038/s41586-022-05016-1

The research was funded by the US Department of Health and Human Services, the National Institutes of Health and the National Institute of Mental Health.

This work was supported by NIH BRAIN Initiative grants MH117064, MH117064-01S1, R21DK128662, T32GM136651, F30HD106694, and Schmidt Futures.

Leave a Comment