The world has been buzzing with the news of the first successful transplant of a porcine (pig) heart into an adult human.

Throughout decades, the idea of Xenotransplantation (the transplantation, implantation into a human recipient of live cells, tissues, or organs from a nonhuman animal source) has not only mesmerised the medical science enthusiasts, it has also found its place in myths, legends and novels( Icarus and his wings or Lord Ganesha's head).

The apparent success can not only end the sad tale of people dying due to lack of a healthy organ but also open up countless fronts in a new world of possibilities.

What do we say to the God of death- Not today

Maryland resident David Bennett (57) created history on January 7 by dodging death as he became the first person in the world to get a pig's heart.

The highly experimental surgery was performed on him at the University of Maryland Medicine (UMM) only after doctors ruled out any other ways to keep the man alive,

It was either die or do this transplant. I want to live. I know it's a shot in the dark, but it's my last choice," he is reported to have said a day before the surgery," Bernett reportedly said to his family and medical team a day before the surgery.

The University of Maryland School of Medicine (UMSOM), whose faculty conducted the surgery, said in a press statement on January 10, "This organ transplant demonstrated for the first time that a genetically-modified animal heart can function like a human heart without immediate rejection by the body,"

Race to recovery

Although it is too early to call, doctors said things are so far so good as Bennett was responding well to the transplant.

He had spent several months on a heart-lung bypass machine prior to the operation, but doctors said he is now able to breathe on his own although he is still connected to the device so as to not put pressure on his transplanted heart.

"We are proceeding cautiously but are "optimistic that this first-in-the-world surgery will provide an important new option for patients in the future," said Bartley P Griffith to local media.

He is the main man behind the historic surgery.

The promises

Mohiuddin, who is the UMSOM xenotransplantation programme's scientific director and is regarded as being one of the "world's foremost experts on transplanting animal organs", said that the surgery on Bennett was "the culmination of years of highly complicated research to hone this technique in animals with survival times that have reached beyond nine months".

More than 6,000 patients die each year in the US alone waiting for an organ transplant, UMSOM pointed out, with Griffith noting that this "breakthrough surgery... brings us one step closer to solving the organ shortage crisis" as there are "simply not enough donor human hearts available to meet the long list of potential recipients".

The situation has particularly worsened worldwide due to Covid-19 pandemic.

A multinational study published in the Lancet Public Health journal observed 31% drop in the number of solid organ transplants performed during the first wave of the pandemic compared with the previous year.

This decline, according to study estimates, resulted in approximately 48,000 years of patient life lost.

The process

The transplanted heart was harvested from a pig that had undergone genetic editing as scientists removed three genes "that would have led to rejection of pig organs by humans" along with one that would have led to excessive growth of pig heart tissue.

Further, six human genes that would have facilitated the organ's acceptance by the human body were inserted into the pig genome, meaning that a total of 10 unique gene edits were carried out in the pig by the US biotech firm Revivicor.

Reports said that on the day of the surgery, the team at UMM removed the pig's heart and placed it in a perfusion device designed to keep it in readiness for the surgery. Apart from the genetic changes effected in the donor pig, Bennett himself received an experimental anti-rejection drug made by another US-based firm, Kiniksa Pharmaceuticals.

Safety and ethical concerns

Xenotransplants were largely abandoned after the 1984 case involving Stephanie Fae Beauclair, better known as Baby Fae, in California.

Born with a fatal heart condition, the infant had received a baboon heart transplant but died within a month of the procedure due to the immune system's rejection of the foreign heart.

In the 1960s, 12 out of 13 people who received kidneys from chimpanzees died within weeks, while the sole survivor went on to live for an additional nine months.

In the 1990s, scientists halted working on donor pigs when they realised that retroviruses lurking in the animals' DNA could potentially infect human cells.

Research has been under way to overcome the problem, by taking genome editing to another level. After tweaking pig DNA to remove molecules that trigger immune rejection, scientists have made precision alterations that remove dozens of retroviruses from pig tissues in the hope the organs will be safer when they are eventually transplanted.

Animal rights

Amidst all the attention the news is getting, concerns of animal rights activist are falling to deaf ears as usual.

People for the Ethical Treatment of Animals (PETA) has condemned Mr Bennett's pig heart transplant as "unethical, dangerous, and a tremendous waste of resources".

"Animals aren't tool-sheds to be raided but complex, intelligent beings," the organisation said.

The moral dilemma is obvious- How is it not cruel to modify the genes of animals to make them more like humans?

To emphasis on the issue, the scribe wants to mention again how scientists altered 10 genes in the pig whose heart was used for Mr Bennett's transplant so it would not be rejected by his body.

On the morning of the operation, the pig had its heart removed.

Animal Aid, a UK-based animal rights group was cited by the BBC saying," ''Animals have a right to live their lives, without being genetically manipulated with all the pain and trauma this entails, only to be killed and their organs harvested."

There are also concerns over long-term effects of genetic modification on the animal's health which undergo such a gruelling process.

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