Pigs for organ transplants… An unexpected gift for patients with ‘this syndrome’?

Genetically modified pigs bred and raised for organ transplants are unexpectedly becoming a source of joy. They are providing people allergic to red meat from mammals with a chance to taste meat again, medical media outlet Medical Express reported on the 21st (local time).

Alpha-gal syndrome (AGS) is an allergic reaction to products made from the red meat of almost all mammals. The syndrome, which was first reported in the academic world in 2002, is caused by the bite of the ‘lone star tick’, which has a single white spot on its back and is found in the southeastern United States.

Symptoms appear minutes to hours after eating beef, pork, and other red meats, or certain mammalian products such as milk or gelatin. Symptoms include hives, itchy or flaky skin, runny nose, headache, difficulty breathing, abdominal pain, diarrhea, nausea, vomiting, and swelling of body parts such as the lips, face, tongue, and throat, and can be fatal.

Alpha-gal syndrome is named after the glycoprotein alpha-gal (galactose-alpha-1,3-galactose), which is present in the tissues of almost all mammals except humans and their primate cousins. If pig organs are to be transplanted into humans, this glycoprotein must first be removed. The gene that produces alpha-gal is the first gene to be removed from pigs produced by Revivicor, a subsidiary of the U.S. biotechnology company United Therapeutics Corporation, for organ transplants.

Although xenografts are still experimental, Livivicor’s GalSafe pigs received FDA approval in 2020 to be used as a food source and potential source of human therapeutics. No detectable levels of alpha-gal have been found in these pigs over multiple generations.

Livivicor is a company that researches xenotransplantation, not a food company. However, people with alpha-gal syndrome have been asking for GalSafe pork. Since no food company has shown interest in selling GalSafe pork, they started providing free pork to patients with alpha-gal syndrome several years ago.

“We’ve got hundreds of orders coming in,” said David Ayares, CEO of Revivicor, as he opened a freezer full of pork patties, ham, ribs and pork chops. “These are FDA-approved research pigs, so we think it makes sense to provide them to patients,” he said.

Livivicor’s GalSafe pigs are raised on a farm in Iowa and are regularly processed at USDA-certified slaughterhouses to ensure their numbers are in check. Livivicor mails the frozen meat to Alpha-Gal patients who sign up for the program. A bulletin board near the freezer in Livivicor’s corporate office is lined with thank-you notes expressing the joy of eating bacon again.

Pigs with various genetic modifications for xenograft research are housed separately in Virginia, USA.
They are raised on the Revivikor farm. The GalSafe pigs that provided the kidneys for the recent experimental kidney transplant at NYU Langone Health were also raised here.

There is also a question about whether pigs with transplantable organs removed can be eaten as meat. They cannot be used. The strong anesthetics used to ensure that the animals do not feel any pain during the organ removal process do not meet the USDA’s drug-free food standards, explained Dewey Steadman, a spokesman for United Therapeutics.