Artificial kidney is a success in pigs, what about humans?

Scientists successfully test an artificial implantable kidney in pigs. This device might reduce the gap between kidney donors and recipients and free thousands of kidney patients from dialysis
Rupendra Brahambhatt
Bioartificial kidney prototype.
Bioartificial kidney prototype.

University of California San Francisco 

There is a severe shortage of kidney donors in the US. About 92,000 patients on the national transplant waiting list seek a kidney, and due to kidney failure, more than half a million patients have to undergo dialysis many times a week. 

Out of these patients, only about 20,000 can secure kidneys from donors in a year. The situation is even worse in many underdeveloped countries. 

To solve such challenges related to kidney transplants, two scientists,, Dr. Shuvo Roy, a bioengineering expert from the University of California, San Francisco (UCSF), and Dr. William Fissell, a nephrologist at Vanderbilt University Medical Center, launched an initiative known as 'The Kidney Project' in the year 1998.

The project is still ongoing, and its goal is to develop a surgically implantable bioartificial kidney for humans who are living with kidney failure and are not able to find a donor. 

In their latest study, Dr. Roy and his team demonstrated a device known as the bioreactor that works like an actual kidney when planted in pigs. “For the first time, kidney cells housed in an implantable device called a bioreactor can survive inside the body of a pig and mimic several important kidney functions,” the researchers note.

How does the artificial kidney work in pigs?

The bioreactor comprises proximal tubule cells that can be directly linked to a pig's veins and blood vessels. In a real kidney, these cells are responsible for maintaining the pH balance of body fluids and reabsorbing water, amino acids, glucose, and various other biomolecules. 

The researchers surgically implanted the device in some pigs such that the cells inside the bioreactor could reabsorb and regulate the flow of nutrients just like a transplanted kidney.

What’s more interesting is that the immune cells of the pigs, which are supposed to act against any foreign cells, couldn’t attack the proximal tubule cells because a protective silicone membrane covered them.

The trial lasted seven days, during which the bioreactor performed well, and the animals didn’t experience any complications or immune reactions. Like a pacemaker, the device worked in the background without causing any disturbance.

“We needed to prove that a functional bioreactor will not require immunosuppressant drugs, and we did,” said Dr. Roy.

Artificial kidney has immense potential

The researchers will now conduct month-long trials in animals, and if successful, they will go for human trials, which is the ultimate goal. 

A report from the American Society of Nephrology estimates that the US Healthcare system spends a whopping $32 billion annually for treating kidney failure. Still, many patients never get cured because of the high treatment cost and shortage of donors.   

They believe that their device has the potential to free kidney patients from both the physical and financial burden of dialysis. Plus, it could save the healthcare system money and resources.

“The bioartificial kidney will give kidney failure patients new hope beyond the short-term solution of renal dialysis and the longer-term, but impermanent, solution of a living kidney transplant for which donor organs are limited,” the Kidney Project team notes.