Exciting breakthroughs in the realm of transplanting pig kidneys into humans were unveiled on Wednesday by two distinct groups of researchers. These remarkable strides mark important advancements in the developing field known as xenotransplantation.
Xenotransplantation involves employing organs or tissues from non-human sources to address medical conditions in people.
A team of experts from the University of Alabama at Birmingham’s Heersink School of Medicine has made noteworthy headway. They’ve discovered that transplanted pig kidneys generate urine and deliver the kidney’s essential function — filtering out waste from the body. Their findings have been documented in a research letter featured in JAMA Surgery.
Findings of the research
During a recent press conference centered around an ongoing study, a group of researchers from New York University Langone Health shed light on their encouraging findings. These findings underscore the extended effectiveness of a transplant procedure in the long run.
In a significant stride towards medical advancement, both research teams have employed genetically modified pig kidneys in their experiments. These kidneys were transplanted into individuals who had experienced brain death, marking a pre-clinical stage of the human-focused investigation.
The kidneys’ vital role lies in filtering out a waste substance known as creatinine from the bloodstream. Assessing the levels of creatinine in the blood provides insight into the efficiency of this filtration process.
Previous studies have shown that filtration can occur when pig kidneys are transplanted into non-human primates. However, it’s crucial to note that creatinine originates from a substance that fuels muscle activity.
The quantity of creatinine can differ based on muscle mass, and given that average adult humans possess greater muscle mass compared to other primates, this fact adds a layer of complexity to the process.
Study on a 52-year-old man
At the University of Alabama at Birmingham (UAB), an insightful study took place involving a 52-year-old man. This individual was dealing with hypertension along with stage 2 chronic kidney disease.
Before the kidney transplant occurred, the levels of serum creatinine in his blood were significantly higher than the accepted norm. However, within a mere twenty-four hours after the transplant procedure, these levels were reduced by half.
Remarkably, within forty-eight hours, they had returned to a standard range, and this healthy level was maintained throughout the study’s duration—a span of seven days from start to finish.
According to Locke, when it comes to human-to-human kidney transplants, kidneys sourced from living donors demonstrate superior and swifter performance compared to those from deceased donors. The remarkable observation is that pig kidneys exhibited behavior more akin to kidneys from live donors.
Locke elaborated, “What that means is, these are great kidneys, and they’re going to provide really great function for living persons, hopefully in the not-too-distant future.”
Pig kidney transplant findings
In the ongoing research led by the NYU Langone team, detailed findings have not yet been published, but recent updates have been disclosed. The team’s focus has been on monitoring pig kidney transplants in a person who was brain-deceased – Maurice Miller, affectionately known as Mo.
Mo’s passing was attributed to a brain tumor, and his condition was used for this study for nearly two months. A combination of immunosuppressive drugs was utilized alongside the transplantation of the pig’s thymus to safeguard the kidneys against potential attacks by the human immune system.
Dr. Robert Montgomery, head of the NYU Langone Transplant Institute and chair of the surgery department, conveyed that they have not observed any signs of rejection.
Surgeons transplanted a pig’s kidney into a brain-dead man and for over a month, it’s worked normally. It’s a critical step in an operation this medical team hopes to eventually try in living patients. pic.twitter.com/UyhfJsAiM7
— The Associated Press (@AP) August 17, 2023
The kidney from the pig has demonstrated normal renal function and has effectively cleared toxins. Essentially, the pig kidney seems to have taken on all the critical roles a human kidney manages.
Need for further investigation
Although further investigation is warranted, including trials involving living human recipients, the prospect of pig kidney transplants as therapy for individuals with end-stage kidney disease is optimistic. The trajectory of progress being achieved in this field is encouraging for researchers.
Dr. Adam Griesemer, the surgical director of the NYU Langone Pediatric Liver Transplant Program and the Living Donor Transplant Program, emphasized during Wednesday’s press conference, “We’re gaining critical evidence about how well pig kidneys work in the human environment.”
“Over the last 20 years, we’ve gained a lot of information about how pig kidneys work to replace the functions in primates,” he further elaborated. “But the critical question – ‘Will those data be translated exactly to the human recipients?’ – was unknown. And for the first time, we’re…able to supply that information. So hopefully this also gives some assurance to the FDA regarding the safety of initiating phase one clinical trials.”
The pressing need for organ transplants, predominantly kidneys, is pronounced. A staggering eighty-nine thousand individuals are presently awaiting organ transplants, based on figures sourced from the Organ Procurement and Transplantation Network within the US Department of Health and Human Services.