Johns Hopkins researchers found a new way to transplant kidney organs from any donor – regardless of compatibility, and they say it’s saving more lives
than the conventional alternative of long-term dialysis while waiting for the right match.
Every year, about 600,00 Americans are afflicted with end-stage kidney disease. Kidney transplantation is a potent fix, but there just aren’t enough donated kidneys to go around. In addition to the organ shortage, donors and recipients have to be matched for blood type and antigens combinations – another bottleneck that prevents many transplants from happening. Of the 101,189 patients that currently await a kidney transplant, only about 16% of them will receive the organ while about 4.4% die waiting for the operation.
To increase the organ supply available to patients on the transplant list, some researchers have turned to other animals as potential organ donors. Notably, the CRISPR/cas9 gene editing system has renewed xenotransplantation hopes
for organs from pigs. However, this technology is still years away from the bedside for many patients.
With the same goal to increase the available organ supply, Johns Hopkins researchers took a different approach. Fifteen years ago, they started to develop a technique to quiet the recipient’s immune system so that any donor organ can become a match, regardless of HLA type. Now, an eight-year study evaluating this technique in 1,025 recipients finds higher survival benefit compared to those who remained on the waiting list.
The technique is known as desensitization, and involves external filtration of antibodies out of a patient’s blood. After the patient’s immune system regenerates new antibodies, doctors found this set of regenerated antibodies are less likely to attack the transplant organ. The exact mechanism behind this is still unknown, but it seems to work at saving lives.
In 1,025 adult incompatible live donor kidney transplant recipients from 22 centers across the U.S., researchers found consistently higher survival rates in comparison with the control groups, who remained on the waiting list. At the eight-year mark, 76.5 percent of those who had received the incompatible transplant were still alive, compared to 43.9 percent of those patients who were still on the waiting list.
“For the first time, we have definitively shown that incompatible live donor kidney transplantation provides almost twice the survival of a patient’s next best option,” said Dorry Segev, professor of surgery at Johns Hopkins and lead author of the paper. "This is great news for patients who have healthy, willing live donors but who have been relegated to the waiting list because of HLA incompatibilities. Through this study, we now know that those donors can donate today, those transplants can happen and those lives can be saved.”
The estimated cost of desensitization is $30,000 and the transplant operation itself is about $100,000. Still, doctors say this upfront cost is cheaper than long-term dialysis, which costs about $70,000 each year.
Saving more lives at lower costs to the patients is arguable ultimate goal for medicine. And this is why many experts are calling this technique revolutionary. Already, desensitization is being explored for other organ transplants, like liver and lung.
Additional source: Johns Hopkins press release