Artificial livers coming soon
Washington, February 7: Treatment for liver damage may soon reach a new level with the development of a system made up of human liver cells, designed to mimic the function of the organ.
The decades-long quest for a suitable replacement of a dying liver recently saw a sudden boost as scientists began testing on the world’s first artificial liver.
The device, called Extracorporeal Liver Assist Device (ELAD), is a 4-inch plastic disk filled with "immortalized" lab-cultured human liver cells to perform the complicated functions of a the master organ.
The cells are grown around a series of hollow fibers and the patients' plasmadefine is passed through them. Toxins in the plasma are filtered through the fiber membrane, and they get metabolized by the liver cells.
The cells are also made to synthesize essential proteins, enzymes, blood-clotting factors, all of which are sent back into the plasma. The cellular components of blood are added to this filtered plasma and it is returned to the patient.
Liver, unlike other vital organs of the body, has a remarkable capability to regenerate if allowed enough recovery time. Transplant is only carried out when the damage is beyond the liver’s capacity to regenerate.
ELAD helps buy time for the liver to recover on its own and consequently helps delay, or avoid, the transplant.
“If we could buy some time while the liver is recovering, that potentially would be a great advance," says Dr. Lena Napolitano of the University of Michigan, who is among the team of scientists testing the ELAD.
Clearly, the device cannot replace the liver but it "comes closer to replacing the amount of liver" people need, said Dr. Robert Brown of New York-Presbyterian Hospital and Columbia University.
People with progressive hepatitis or cirrhosis may benefit the most from the device.
Previous attempts in this direction had also met with early success but they had to be discarded eventually.
This is still a very early stage; a lot needs to be explored in the field to combat the liver failures effectively. Nearly 28,000 people die from liver disease in the United States each year, and fewer than 6,000 get liver transplants.
The FDA wants to know if three to 10 days of ELAD liver support improves 30-day survival over the patients who receive the standard supportive care available today.
Vital Therapies Inc., the manufacturer of the device, claims that 85 percent of the first 49 patients studied in China, had better short-term survival compared with half of patients given regular care.
The device carried a $30,000 price tag; the doctors also need to evaluate if the benefits of ELAD make up for the huge cost.