[00:00.00]Scientists are raising pigs to produce human organs at a specialized research farm in the American state of Virginia.
[00:12.81]A medical company called Revivicor runs the farm in the rural community of Blacksburg.
[00:22.21]The area is surrounded by the Blue Ridge Mountains.
[00:26.39]Workers at the farm follow intense measures in an effort to prevent infection and disease spread.
[00:37.23]About 300 pigs of different ages live on the research farm.
[00:44.04]Some animals raised there have already provided the first genetically changed pig organs ever transplanted into humans.
[00:55.90]Individuals working at the center must undergo a series of safeguards aimed at preventing infections in the organs grown for people.
[01:09.71]Matthew VonEsch is an executive with United Therapeutics, the parent company of Revivicor.
[01:18.97]He told The Associated Press the research farm was designed with the goal of protecting the pigs "against contamination from the environment and from people."
[01:34.57]David Ayares is the founder and chief scientific officer of Revivicor.
[01:42.31]He described the farmed pigs to the AP as "precious animals" because of their ability to help save human lives.
[01:54.81]The research farm looks very different from a traditional animal farm.
[02:01.14]This is because of the strong security and cleanliness measures needed.
[02:07.54]It was built to meet U.S. Food and Drug Administration (FDA) safety requirements.
[02:17.45]For example, pigs living at the farm only drink water that is highly filtered. All food also gets disinfected.
[02:28.41]Revivicor's farm aims to produce human organs that can be used in scientific experiments or actual transplants.
[02:40.83]There is currently a great need in the U.S. for organ transplants.
[02:47.03]Thousands of people are waiting for a donor organ.
[02:51.89]But experts say there will never be enough human donors to fill that need.
[02:58.50]Using animal-grown organs for human transplants is one possible way to deal with the shortage.
[03:08.58]Scientists use genetic engineering methods to grow organs in animals.
[03:15.46]These organs behave more like human ones than animal ones, which reduces the chances that the body will reject the animal organs.
[03:28.05]Teams have been working for many years to grow more humanlike organs in pigs.
[03:36.45]So far in the United States, four "compassionate use" transplants have happened.
[03:44.52]These cases involved last-minute experiments to transplant pig organs into humans who faced life-threatening conditions.
[03:56.68]Two transplants involved hearts and two involved kidneys.
[04:02.81]Revivicor provided both of the hearts and one of the kidneys.
[04:09.08]All four patients died within a few months. Still, experts say each transplant offered the possibility for valuable, real-life research.
[04:23.61]The goal is to one day attempt to put pig organs into human transplant patients who are not quite as sick.
[04:33.74]Revivicor's Ayares said the company is aiming to produce organs in the pigs that closely meet the size and needs of each patient.
[04:47.81]The idea is that such organs will perform better than human-donated organs because they are younger and free of disease.
[04:59.26]Ayares added that transplant doctors who have received organs from Revivicor's farm say, "Oh my god, that's the most beautiful kidney I've ever seen."
[05:13.62]He said the reaction is the same when they get "a pink healthy happy heart from a young animal."
[05:22.19]Officials at Revivicor say the biggest difficulties they face include overcoming the rejection of pig organs in humans and preventing animals from carrying unknown infection risks.
[05:40.07]Scientists try to deal with the rejection issue by employing different engineering methods to make the pig organs as humanlike as possible.
[05:52.84]Genetic changes are made to the pig eggs that Revivicor receives.
[05:59.64]The engineered eggs are then nurtured in the lab with the hope of producing a healthy embryo.
[06:07.44]The embryos are then taken to the research farm to be put inside living pigs.
[06:15.02]It is expected to take years of experimentation to prove whether animal organ transplants will work long-term in human patients.
[06:28.05]But if the efforts succeed, United Therapeutics plans to open additional research farms to produce up to 2,000 organs a year.
[06:41.94]Ayares said the efforts are currently at a point where several studies have suggested "there's no immediate rejection" of the genetically engineered pig organs.
[06:55.54]He added, "The next two or three years are going to be super exciting."
[07:03.32]I'm Bryan Lynn.
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Words in This Story
transplant - v. to perform a medical operation in which an organ or other part that has been removed from the body of one person is put into the body of another person
contaminate - n. to make something dirty or poisonous
precious - adj. very important or valuable
filter - v. to pass a liquid or gas through a piece of equipment in order to remove solid pieces or other substances
compassionate - adj. showing compassion: a feeling of sympathy for others who are suffering
nurture - v. to care for or encourage the growth of something
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