It’s the summer of 2015. Lee Hall, age 26, lies sedated on the operating table while the medical team prepares everything necessary to transplant a new heart into her body. The surgeons are nervous; the heart they are about to put into Lee’s chest isn’t as cold as the donated organs they receive usually are, but instead it’s warm. And what’s even more amazing is that it’s beating in their hands!
Lee’s operation went well, and all thanks to the Organ Care System (OCS), an invention from a Massachusetts company called Transmedic that revives the donor heart and keeps it at body temperature, nourished and oxygenated, while waiting to be transplanted. The interesting thing about this revolutionary technology, which is included within the techniques known as warm infusion, is that it allows metabolically active organs to be transplanted. This is a more effective strategy than cooling the extracted organ of the donor to 4°C (hypothermia), as has been done until now, which reduces the metabolic rate of the tissues by 90% to gain time until the operation, but which has many limitations, including that the maximum time between removal and transplantation is around six hours. The creators of the new technique believe that, thanks to their innovation, the rate of successful heart transplants has increased by 30%.
But the heart is not the only organ that can be transplanted in action. The OCS has also been used for the transplantation of lungs that were breathing outside the body of the donor. “Lungs are very sensitive organs, which are easily damaged in the donation, and by keeping them active with this technology we can correct any problems before placing them into the recipient,” says Abbas Ardehalia, cardiothoracic surgeon in Los Angeles and head of the medical team that performed the procedure. When in 1954 Joseph Murray performed the first successful organ transplant –a kidney– he could not have imagined how far we would come in developing these surgical techniques.
In recent years, other important milestones have also been reached in this area. As a case in point, in 2014 a Swedish woman became the first to give birth with a transplanted uterus, received from a 61-year-old anonymous donor. Another reproductive organ was the protagonist in the challenge faced by Curtis L. Cetrulo and his team of surgeons at Massachusetts General Hospital (Boston) in early 2016 in which they attempted to transplant a complete penis. The successful operation, which lasted 15 hours, involved the reconstruction of complex vascular and neural structures so that the donor organ would maintain its urinary and sexual functions. Another success was achieved in 2009 when surgeon Daniel S. Alam triumphantly left the operating room at the Cleveland Clinic in Ohio after successfully performing the first full transplant of the face and upper jaw, which allowed his patient, a 46 year old woman, to even regain the ability to speak and the senses of smell and of taste.
Another important page in the history of surgery was written at the University of Texas (USA) in early 2016 after Jesse Creed and his colleagues carried out a multiple transplant of the skull, scalp, kidney and pancreas. This operation involved a combination of many different tissues such as skin, muscle, blood vessels, nerves and bones, but also whole organs.
For the moment, what cannot be transplanted is a whole brain. But that does not mean there is no surgical solution for the diseases that damage brain tissue, such as Alzheimer’s, epilepsy or Parkinson’s. At the University of California (USA) they have shown that the transplantation of embryonic neurons into the cerebral cortex has a cell survival rate so high that it could serve as a therapy to treat all kinds of neurodegenerative diseases. Moreover, in their experiments they demonstrated that after the transplant the brain undergoes a period of plasticity in which the seizures and disruptions of movement associated with Parkinson’s are reduced.
For other organs, cell transplantation is not a bad idea either. In fact, experts believe that the use of stem cells, along with the creation of artificial tissues and organs using 3D printers, provides the most promising line of research in transplant medicine. After all, we must not forget that the demand for organs exceeds the supply, so it seems essential that we find alternatives.
As for the problem of organ rejection, which until now has been addressed by minimizing the activity of the recipient’s immune system –with the associated risk of contracting an illness–, scientists are experimenting with new strategies. One of the most promising was announced a few months ago by a pair of researchers from the University of British Columbia: a gene therapy that programs certain cells to defend the new organ from the attacks of our own immune system, which normally detects that there is a “foreign” element and tries to destroy it. A brilliant idea designed to ensure that the majority of transplants reach a successful conclusion.