By Dr. Louis M. Profeta
If you need a kidney transplant tomorrow, chances are you will wait around three years. Even before you get transplanted, assuming you live, you will most likely spend years on dialysis. Right now there are more than 100,000 people in the US waiting for kidney transplants. Every year nearly 5,000 people will die just waiting for one.
On the horizon though, is a potential source of donors that may revolutionize kidney transplantation as we know it. Best of all, it may be that we only have to go to a local farm to get one.
In 1984 at Loma Linda University Medical Center an infant girl known as ” Baby Fae” received the first xenotransplant, also known as non-human to human transplant. In this case, Baby Fae received a Baboon heart in a last ditch effort to save her life. Sadly, Baby Fae died 21 days later.
The roadblock to success with this kind of therapy in transplantation has always been how best to keep you from rejecting your new organ. This is the cornerstone of the science whose goal is to best match your gift and to protect it for the remainder of what we hope will be your long life. This is essentially the same science that determines blood types and why we need to match blood donors with blood recipients.
You see, your body is able to recognize an unmatched transplanted organ such as a heart, kidney or liver, as not being your own. This recognition of the unmatched organs is triggered when certain proteins on their cells cause a cascade of biological processes in which your body mounts an attack on your newly transplanted organ. This leads to organ rejection and possibly even your death.
The ability to successfully transplant an organ is a product of two fundamental therapies. First we have find an organ from a donor whose proteins most closely look like yours, and second we have to protect that organ with medications meant to keep your immune system from attacking your new transplant. Even then the organ is often rejected, an incredible loss not only for you but for the family of the deceased or living donor who graciously tried to save your life.
The trouble with the Baby Fae case is that the heart of the baboon, while similar in size and structure to her own heart, simply did not look like her human heart on the cellular level. Fae’s own immune system attacked the baboon heart and she died.
Over the years since the early 80’s there has been a resurgence in research the focus of which is to alter the cells of non-human species and ultimately make those cells resemble those of a human being.
Scientists have started to make huge inroads through cloning. The model that seems the most promising is not a primate such as a monkey, or chimp. Instead the animal that holds the most promise of all potential animal donors is of all things…the pig. Incredibly scientists have succeeded in removing those proteins from pig cells that are most responsible for rejection. In the simplest of explanations, these pig kidneys, on the cellular level are coming close to being indistinguishable from humans. They are so close in fact that they may not even need to be matched. You can essentially put the same kidney into…well anybody.
Transplant surgeon Dr. Joseph Tector, and his laboratory at the University of Alabama at Birmingham, is on the forefront of this scientific advancement. They are very close. So close in fact that I predict, for the coming year, that Dr. Tector will put the first pig kidney into a human being, possibly as early as the end of 2017, or the very beginning of 2018. I also predict this will work and change the way we think of organ transplantation forever.
Down the line I envision huge cloning farms, producing the same pig over and over. Essentially a continuous and unlimited source of kidneys, so many in fact that we will probably need hospitals solely meant for kidney transplantation. In time I predict this process will eventually translate to livers, hearts, even intestines but for now the focus is on kidneys. I am excited to see what will happen in the near future and where we are headed. We just may be on the verge of one of the most significant advancements in medicine in the last fifty years. One that few even knew was within our grasp.
Perhaps George Orwell was right, at least when it comes to the kidney, in the very near future we may not be able to tell which is which.
Dr. Louis M. Profeta is an emergency physician practicing in Indianapolis. He is the author of the critically acclaimed book, The Patient in Room Nine Says He’s God.
