Damaged liver repaired, transplanted after 3 days outside body

The Zurich research team Liver4Life — involving University Hospital Zurich (USZ), ETH Zurich and the University of Zurich (UZH) — has reported the successful treatment of a damaged human liver for three days outside of the body, before implantation of the recovered organ into a cancer patient. One year later, the patient is doing well.

The liver has a unique ability to regenerate after damage, with international scientists recently determining that it replaces its cells equally well in young and old people — so no matter a person’s age, the liver is always on average less than three years old. That said, not every liver will be suitable for transplantation, so the Liver4Life team has spent the last several years working to repair and restore damaged livers in a controlled environment outside of the body.

The team’s so-called perfusion machine, which was developed in-house, mimics the human body as accurately as possible, in order to provide ideal conditions for the human liver. A pump serves as a replacement heart, an oxygenator replaces the lungs and a dialysis unit performs the functions of the kidneys. In addition, numerous hormone and nutrient infusions perform 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. In January 2020, the multidisciplinary team confirmed that perfusion technology makes it possible to store a liver outside the body for several days.

In the case of the recent transplant, the team prepared the liver in the machine with various drugs. In this way, it was possible to transform the liver into a good human organ, even though it was originally not approved for transplantation due to its poor quality.

The multi-day perfusion — ie, the mechanical circulation of the organ — enables antibiotic or hormonal therapies or the optimisation of liver metabolism, for example. In addition, lengthy laboratory or tissue tests can be carried out without time pressure. Under normal circumstances, this is not possible because organs can only be stored for 12 hours if they are stored conventionally on ice and in commercially available perfusion machines.

A cancer patient on the Swisstransplant waiting list, who was in urgent need of a new liver due to a rapidly progressing tumour, was given the choice of using the treated human liver. The organ was transplanted in May 2021, with the patient leaving hospital a few days after the procedure. The transplant was documented in the journal Nature Biotechnology.

The next step in the Liver4Life project is to review the procedure on other patients and to demonstrate its efficacy and safety in the form of a multicentre study. Its success would mean that in the future, a liver transplantation, which usually constitutes an emergency procedure, would be transformed into a plannable elective procedure. At the same time, a next generation of machines is being developed.

Image caption: The Zurich team connects the donor liver to the perfusion machine in the cleanroom. Image credit: USZ.

Please follow us and share on Twitter and Facebook. You can also subscribe for FREE to our weekly newsletters and bimonthly magazine.