- Egenesis, a startup that raised $US38 million in March, just successfully used the gene-editing tool CRISPR to knock out a key virus in piglets.
- The virus-free pigs could get us a step closer to transplanting pig organs into humans, something that’s been a challenge in the past.
- Next, the company may have to make some more tweaks to make sure our immune systems don’t reject the pig organs and ultimately test out how safe and effective these organs are in humans.
Egenesis, a startup that’s using the gene-editing tool CRISPR to make pig organs viable for transplants into people, just became the first company to make pigs that don’t transmit a key virus, a move that could get us closer to pig-organ transplants for humans.
The company, which raised $US38 million in March and is cofounded by Harvard geneticist George Church and 31-year old Luhan Yang, wants to knock out certain genes in pigs that could cause diseases or organ rejection in humans, making it possible for those pig organs to be transplanted.
On Thursday, the Egenesis team announced in the journal Science that it had produced 37 piglets that had inactivated Porcine Endogenous Retrovirus, or PERV. The virus, which is part of the pigs’ DNA, has been an issue for human-pig transplants in the past because of concerns that it could infect humans. Inactivating the virus could ease those concerns.
“This is the first publication to report on PERV-free pig production,” Yang, who is chief scientific officer at Egenesis, said in a news release.
Why pig organs could help with transplant shortages
According to the US Health Resources and Services Administration, there are more than 118,000 people in the US who are on the waiting list for organ transplants. In 2016, there were a record-high 33,500 transplants, but an estimated 22 people die each day waiting on a new organ. Getting organs from animals — particularly from pigs, whose organs tend to be close in size and work similarly to human organs — could be the solution to that shortage.
But there are two huge hurdles to getting animal-organ transplants to successfully work in humans — a process known as xenotransplantation. The first, Yang told Business Insider in March, is the virology, or the fact that pigs carry genes encoded with viruses that could transmit disease to humans — that’s the PERV genes that Egenesis is working to deactivate.
The second hurdle, she said, is the immunology. Since the pig organ would be foreign to the body, the person’s immune system might try to kick it out, rejecting the organ. Those proved too challenging for a slew of researchers going after this subject in the 1990s.
Ideally, CRISPR will help tackle those issues “that were insurmountable before,” Yang said. “We think the advancement of gene editing can help us address both of them,” Yang said.
How Egenesis’ process works
- Egenesis wants to build genetically modified pig clones that tackle both the virology and immunology challenges that come with taking a pig organ and putting it in a human.
- To do that, you first genetically modify pig cells. That was the first step Egenesis took back in 2015 when it inactivated 62 virus genes in pig embryos.
- From those cells you can clone pigs that grow up, at which point you can take the organs from them. That’s where today’s news comes in: Yang and her team were able to create 37 piglets, 15 of which have survived and the oldest were 4 months old.
- Now, the company can test the pig to make sure the organs are safe and effective, and eventually move the pig organs into clinical trials.
Egenesis isn’t the only company trying to harness animal organs for use in humans. United Therapeutics is also going after xenotransplantation, while others are taking a different approach of trying to grow human organs in pigs. And the world’s largest pork producer is exploring how to grow tissues and organs that could be used in human transplants. Yang said the number of companies starting to work on this again is good news.
“I think it’s a good sign that the field has been revived,” she told Business Insider.
Business Insider Emails & Alerts
Site highlights each day to your inbox.