Review
Not long ago, the first patient in human history to transplant a pig heart died because of a postoperative reaction after surviving for more than two months, which once again cast a bleak shadow on the clinical practice of organ transplantation.
In fact, there are many precedents for similar surgeries in modern times, but so far they have not survived, such as 38 years ago, doctors transplanted the heart of a chimpanzee to a little girl.
It may sound more convincing than a pig's heart, but the end result still did not work out, why is the development of organ transplant technology so difficult, and what will be its future prospects? Let's explore it together today.
Chimpanzee heart transplant
In the case of a chimpanzee heart transplant, the recipient of the transplant was a baby girl who was born with congenital heart disease, which led to atrial development defects, which caused great obstacles to blood circulation, and if this condition was not improved in time, it would soon die of heart failure.
The baby girl named Stephanie was lucky in a way, because it was already the 1980s, medical technology had made great progress compared to before, clinical heart transplantation was already very mature, and if there was a suitable heart, stephanie could survive by changing her heart.
But the problem was that there was no heart that could be used at that time, and passively waiting for the miracle to happen would only exacerbate the deterioration of the disease day by day, and because she was still a baby, Stephanie's body was very weak and could not bear the burden of heart failure on the body.
Seeing that the situation is gradually critical, the doctors have proposed a new plan, that is, to replace the human heart with the heart of the animal, the so-called dead horse as a live horse doctor, if you do it, Stephanie still has a glimmer of life, if you don't do it, she only has to die, so the child's family also agreed to the doctor's advice.
According to the doctor's vision, even if it is the heart of an animal, it will take a while for the human body to produce a rejection reaction.
During this time, you can continue to wait for the right heart to appear, as long as it appears, you can immediately re-transplant, although it is a relatively large physical damage for Stephanie, but at least save your life first.
In this way, the doctor transplanted a chimpanzee heart into Stephanie's body, and she also woke up smoothly, and for three weeks, the girl's body did not appear new abnormalities, and her state was much better than before.
But on the 21st day, Stephanie had a violent rejection reaction, and in a very short time she completely failed and died.
The reason why the rejection reaction was so drastic that experts at the time may have been mainly due to blood type discrepancies, because Stephanie's blood type was O and chimpanzees' blood type was AB, but to find a chimpanzee with O blood under natural conditions was almost a needle in a haystack, and it can only be said that the doctor has done his best.
Of course, a young life is gone, and the hospital and the doctors involved in this operation are bound to be criticized a lot, such as why they did this operation in the first place, whether the whole process is compliant, whether the parents of the baby girl are fully aware of the possible consequences, etc., which have become the key to public doubt.
At the same time, the discussion on xenotransplantation is also very intense, and the ethical, legal, and technical issues have not been debated until today.
Failure of xenografting
So why do heterogeneous organ transplants fail? In fact, whether it is the same species or different species, as long as it is a transplant between two individuals, there may be a situation like Stephanie, which is the so-called rejection reaction, which is also the root cause of the death of most transplant patients.
What is rejection? In essence, this is a defense mechanism of the human body against external substances that do not belong to itself, from organs to tissues and even cells, as long as they enter the immune system, they will be recognized by our bodies and judged as invading harmful substances, and then rise up to resist and produce a strong stress response.
For example, in babies like Stephanie, if you choose individuals with different blood types for organ transplantation, it will be prone to rejection.
Because their bodies are still in the development stage, although incompatible blood types are acceptable at first, it is likely that a series of problems will arise because there is no hemagglutinin, and they can only rely on drugs to maintain life, and once rejection begins, the consequences are unimaginable.
In the case of pig heart transplantation, the selection of the heart is more rigorous, to be precise, the pig heart has been genetically modified at the same time from the beginning of breeding, and the purpose of this is to make it more suitable for the human immune system.
The reason why pig hearts are chosen instead of chimpanzees' hearts that are more closely related to humans is because pigs are a better medical breeding object than chimpanzees, with higher yields, more experimental data, and more controllable for clinical practice, so it has also become a priority choice in xenotransplantation now.
Although the first transplant patient did not survive, the time of more than two months has been significantly better than previous cases, and we are grateful to these patients who are willing and willing to participate in this experiment.
Although their lives have not been saved, as medicine continues to advance, xenotransplantation will gain new developments, and when this technology really succeeds, it will change the trajectory of the entire human medicine and save more lives.
epilogue
Of course, once the xenotransplantation is successful, a series of problems must also be solved, from ethics to law are possible places of dispute, how the society at that time will deal with the potential contradictions, we need to be institutionally and culturally prepared in advance.