The Wyss Zurich team connects the donor liver to the perfusion machine in the clean room. Credit: Wyss Zurich
In 2020, after five years of work, Swiss researchers lengthened the amount of time a donor liver could remain outside a body from barely one day to an entire week. That advancement alone is significant enough to save many lives, but now, the team has taken it a step further—accomplishing something that has never been done before in medicine.
In research published today in Nature Biotechnology, the same team successfully treated an originally damaged human liver in a machine for three days outside a body and then implanted the recovered organ into a dying cancer patient. One year later, the patient is thriving.
In 2015, researchers launched the Liver4Life project under the umbrella of the Wyss Zurich Translational Center out of the University of Zurich and ETH Zurich. The project brings together highly specialized researchers from a diverse range of disciplines to solve biomedical challenges. Their first challenge? Keep a liver alive outside the body for a week.
The team accomplished this in January 2020 with the debut of a newly developed perfusion machine. The machine imitates the human body as closely as possible—a pump serves as a heart replacement, an oxygenator replaces the lungs and a dialysis unit replaces the kidneys. In addition, numerous hormone and nutrient infusions take over the functions of the intestine and pancreas. Like the diaphragm in the human body, the machine also moves the liver to the rhythm of human breathing.
The perfusion machine extended the survival time of a donor liver to seven days and, most importantly, opened it to the possibility of treatments, like liver regeneration and oncological therapies.
The treated human liver approach was tested in May 2021 as part of an approved individual treatment program for a cancer patient on the Swiss transplant waiting list. The patient had little chance of receiving a liver from the list as his tumor was rapidly progressing. So, he was approved for an alternative approach.
The researchers used a liver that was deemed too poor quality for transplantation and prepared it in the machine using a cocktail of drugs over three days. According to the team, the multi-day perfusion enables antibiotic and hormonal therapies, as well as the optimization of liver metabolism.
Following the patient’s consent, the treated liver was transplanted in May 2021. He left the hospital a few days after the surgery and, one year later, is still doing well.
“Our therapy shows that by treating livers in the perfusion machine, it is possible to alleviate the lack of functioning human organs and save lives,” said Pierre-Alain Clavien, director of the Department of Visceral Surgery and Transplantation at University Hospital Zurich.
Although the U.S. is performing more organ transplants than ever before, there are still more than 100,000 people awaiting a life-saving transplant. Every 9 minutes someone is added to the national organ transplant waiting list. Of the patients waiting, roughly 85% are in need of a kidney, while 11% are in need of a liver transplant. The more organs that can be treated from poor quality to good, the more lives that can be saved.
“The interdisciplinary approach to solving complex biomedical challenges embodied in this project is the future of medicine,” said Mark Tibbitt, professor of macromolecular engineering at ETH Zurich. “This will allow us to use new findings even more quickly for treating patients.”
The next step for the Liver4Life project is to review the procedure on other patients and demonstrate its efficacy and safety in the form of a multicenter study. Its success would ensure a future in which a liver transplantation, which is an emergency procedure currently, becomes a plannable elective procedure. The Liver4Life research team says they are also working a next-generation of biomedical machines.