The liver has the greatest regenerative capacity of any
organ in the body. However, when the liver is injured beyond its ability to
regenerate itself, and a transplant is not readily available, there are few
options for patients.
Led by Scott
Nyberg, M.D., Ph.D., researchers are refining their own version of a
bioartificial liver, known as the Spheroid Reservoir Bioartificial Liver (SRBAL).
This device contains pig liver cell (hepatocyte) spheroids, which replace a
patient’s liver function.
artificial liver would bridge the gap until a donor liver becomes available or
if it could help the patient avoid the need for a transplant altogether,” says
While the artificial liver device has been successfully
demonstrated on pigs with acute liver failure, the ultimate goal is the bedside
treatment of patients in liver failure. With a research grant from Regenerative Medicine Minnesota, Dr.
Nyberg and his team are continuing to study whether the artificial liver could
function similar to a kidney
dialysis machine. The patient would be connected to the device, and much like
dialysis, the artificial organ would, perform critical bodily functions
while the liver heals and regenerates.
“The results of our third large animal study were published in
2019,” says Dr. Nyberg. “Pigs were chosen for the early studies because
their metabolism is similar to ours and because they could provide an abundant
supply of liver cells.”
In the treatment group, all of the animals survived the
therapy and were up walking around with recovered livers at the end of the
study. The results have paved the way for future clinical trials.
the SRBAL is similar to kidney dialysis, the liver is more complicated. It does
metabolic activities, detoxifies wastes, and synthesizes proteins. Because of
this, the SRBAL incorporates living cells– in this case, from pig livers – to
carry out such vital functions for a patient.
“We’re ready for to move into Phase I trials in humans,”
says Dr. Nyberg. “However, funding a medical device trial using living cells in
humans is quite expensive, and we’ll need to build a new clinically acceptable
SRBAL suitable for human use.”
Once funding is established and the new device developed,
the first study in humans would be a Phase I safety study to make sure the
machine is safe for use on people. Second is a dosing study to determine the
efficient dose of liver cells to put in the bioreactor to repair the liver.
Once the Phase I and Phase II studies are complete and encouraging, a Phase III,
multicenter randomized study would follow.
is an exciting time for transplant surgery,” says Charles Rosen, M.D., director of the William J. von
Liebig Center for Transplantation and Clinic Regeneration at Mayo Clinic. “The
need for organ donation is high, and this research couldn’t come at a better
SRBAL would be most appropriate for patients who have acute
liver failure and are awaiting transplant, experience an overdose of
medication, or those who aren’t candidates for liver transplant.
“There’s a lot of work to be done, but this is a promising
solution to the donor organ shortage in some cases” says Dr. Nyberg. “Many acute
liver failure patients would have the opportunity to recover, if only they had
time for their liver to regenerate and heal.”