Today, while cruising my Facebook feed, I encountered a truly incredible story. Science ran with the provocative title “In a first, pig lung survives and functions—briefly—in a person.” This covered the most recent study from Nature Medicine by the surgeon Jianxing He and his colleagues. The patient, was 39 year old male who had suffered an intracranial hemorrhage which had resulted in brain death.

In short, a genetically engineered pig lung, designed to survive in humans, was transplanted into this brain-dead patient. Instead of dying in hours these genetic modifications allowed the patient to stay alive with functioning lungs for 9 days. The patient was seen to be delivering oxygen and clearing CO₂. Eventually, after a problematic immune response, the lungs were removed for further study. The man was ultimately taken off life support in accordance with his families wishes.

The comment section on these articles is a true range of emotions. On the one hand, one has to consider what is in the best interest of the recipient, given the low likelihood of success. On the flip, context matters. This patient’s likelihood of recovery is near zero, and what we learned from this study has the opportunity to move the field of transplant forward. It offers the potential for a new source of organs which could be a major benefit to society.

The current shortage of organs like lungs makes it slim pickings for patients in need. A part of me recognizes the argument that this research is “a building block that is required for the field to incrementally advance.” However, another part of me is left wondering about alternatives.

Past Transplants Make This a Familiar Story

Using animal organs for transplant is far from new phenomenon: weather we are talking about a transplant of rabbit kidneys into a child in 1905 or lamb kidneys in 1923 a true menagerie of animal organs were used in the early 20th century. These early attempts were rapid failures due to organ rejection by the immune system.

The kidney was the first successful solid-organ transplant in 1954. This first attempt used identical twins which meant immune suppression wasn’t needed, but also made this an edge case. Kidney transplants beyond twins had to wait until 1961, when immunosuppressive agents such as corticosteroids and azathioprine were needed to stave of organ rejection.

Early transplant cases focused heavily on kidneys. Heart transplants, pioneered by South African heart surgeon Christiaan Barnard, with support from his brother Marius Barnard, share some similarities with a recent case in Nature Medicine. In many ways, the challenges overlap.

In December 3, 1967, Denise Darvall, a 25-year-old who was brain dead due to a car accident, had her heart transplanted into a 53-year-old suffering from heart failure at Groote Schuur Hospital in South Africa. This is recognized as the first successful human transplant. The patient survived only for 18 days after surgery and ultimately succumbed to pneumonia. While this may seem like modest progress, Barnard’s track record improved over time. The second recipient remained active 18 months post surgery. By the 6th patient, Barnard was on a roll, and the patient lived for 24 years. This process of iteration and improvement one would hope is the same path we are looking at with these early xenotransplantation studies with genetically engineered pig lungs.

This doesn’t mean there wasn’t friction. South Africa was ahead of the curve in terms of heart transplant. Some in the US were more reluctant to take chances with heart transplant concerned with the legal and ethical implications of such procedures. A month after Barnard’s early pioneering work, Norman Shumway attempted to conduct the first heart transplant in the US. During the surgery Shumway’s chief resident is reported to have asked “Do you think this is really legal?” to which Shumway replied “I guess we’ll see.”

This early work, had to balance the considerations of both donor and recipient making it a delicate balancing act. This is part of what makes the use of genetically engineered pig organs so attractive. It offers the ability to overcome the current human organ shortage, while allowing us to put greater focus on the needs of the recipient. This ultimately assumes we can extend life expectancy beyond days using these new technologies for xenotransplantation.

Even more important than the aforementioned technological innovation, is the need for organ donors. Until xenotransplantation is refined, becoming an organ donor is the best way to address the current global shortage. In the US, for example, 13 people die everyday waiting for an organ transplant.

Additionally, no matter your moral character, your organs still offer hope after death. Take for example the hypothetical case of Coleman Sweeney:

So what do you think? Are these xenotransplantation studies with pig lungs the best option for the future? Is there an alternative in transplant I’m missing? Feel free to tell us in the comments.

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Organ donation saves lives. Whether you’re in Australia, Canada, the US, the UK, South Africa or somewhere else entirely. Someone can use your organs when you’re done with them. Consider becoming a donor today.