Those affected hope for medicines and cosmetics that do not trigger an allergic shock. Her allergy was caused by a tick bite.
Not only organs, but also meat and other parts of genetically modified pigs could be used for medical purposes (an unmodified animal is shown).
“Bite into a burger or a schnitzel like you used to.” What sounds like the sigh of a climate-conscious new vegetarian has a much more dramatic meaning for some meat allergy sufferers: They want food without a life-threatening circulatory collapse. Genetically engineered pigs, originally bred as organ donors, could not only enable people with a special meat allergy to have a relaxed barbecue with friends, but generally lead a more carefree life.
The culprit is a sugar molecule
At least that’s what all patients with the so-called Alpha Gal Syndrome (AGS). These individuals are allergic to a sugar molecule that is not found in humans but is found on a variety of cells in all other mammals. This is the sugar with the complicated name galactose-alpha-1,3-galactose, or alpha-gal for short.
After consuming mammalian meat, dairy products or even cosmetics with animal ingredients, AGS patients develop a whole series of classic allergy symptoms: from thick lips to shortness of breath and itchy skin to circulatory problems and loss of consciousness. Many suffer from abdominal pain, nausea and diarrhea.
“In the case of alpha-gal allergy sufferers, the strength of the reaction varies greatly,” explains Andreas Bircher, an allergist from Basel. “Some get severe symptoms after just a few bites of pork schnitzel. Others, on the other hand, only after they have emptied their plate, drunk alcohol or subsequently been physically active. »
Since the allergic reaction to animal sugar usually occurs three to six hours after eating, many sufferers report months of odysseys through doctor’s offices until alpha-gal is finally recognized as the cause of their allergy attacks. In addition, the classic allergy test usually does not provide any AGS diagnosis. The only therapy is avoidance of foods and products with mammalian ingredients.
Company gives away meat for free
But that’s exactly what the GM pigs could change. Because the so-called GalSafe pigs lack special molecules on the surface of their cells due to genetic engineering, including precisely the alpha-gal sugar to which AGS patients are allergic. Thus, meat and other components of GalSafe pigs should be safe for AGS patients to consume or use.
The GalSafe pigs have recently become media stars. The heart that was implanted in a seriously ill man in the United States in January came from one of them. He only survived a few weeks with it. But the first transplant of an entire animal organ into a human made headlines around the world.
Incidentally, the function as a supplier of replacement organs for humans was the original reason why the GalSafe pigs were developed. The idea behind it: Molecules are genetically eliminated from the animal cells, which our human immune system recognizes as foreign and therefore attacks. However, while the pigs whose organs are intended for transplantation lack several molecules, products without alpha-gal are sufficient for AGS patients.
Now the secondary career of the GalSafe pigs may have begun. At the urging of patient groups, the Revivicor company has been giving away free packages containing bacon, ham, minced meat and some other cuts of meat from GalSafe pigs in the USA since the end of last year. “The bacon sandwich was my Christmas present to myself,” “It tastes good and doesn’t cause any problems at all,” is how those affected rave about the carefree enjoyment of meat in Internet forums after years of abstinence.
However, there is still no official online ordering system, and you will not find GalSafe products in the supermarket. Rather, order forms are circulating in the USA in self-help groups of AGS sufferers.
Revivicor is now reportedly considering breeding GalSafe pigs for consumption with the help of licensees. A farm with up to a thousand such pigs and its own slaughterhouse is to be built in the USA, and the GalSafe meat and other pork parts are then to be marketed commercially.
However, until further notice, consumption of GalSafe meat is at your own risk. Revivicor received one from the US FDA in December 2020 Permit for the GalSafe pigs and their parts for general food consumption and therapeutic purposes. In addition, the breeding of the animals was classified as harmless to nature and in line with animal welfare.
Consume at your own risk
However, it is not clear whether a GalSafe burger is safe for an AGS patient to eat. Because this was also not tested as part of the FDA approval.
The allergist and AGS expert Jörg Fischer from the Klinikum Oldenburg is therefore by no means convinced that GalSafe burgers and schnitzel are more than a marketing gimmick, especially if such products were once sold at high prices. “At best, this solves a luxury problem, because for many AGS patients only the consumption of mammalian meat is medically problematic. However, AGS sufferers could eat chicken and fish. It is still completely unclear who should receive such products.”
However, his colleague Scott Commins from the University of North Carolina at Chapel Hill hopes that many parts of GalSafe pigs will become valuable for medicine in the future. Because some AGS patients are so sensitive to Alpha-Gal that they also show serious to life-threatening allergic reactions to gelatine-containing substances such as some blood substitutes, heparin, vaccines or medicines that came into contact with animal cells during production.
Not only would these people be happy with pork, but other alpha-gal-free medicinal products would be life-saving for them, Commins says. He now wants to start a study to clarify whether and which GalSafe products can be used safely in AGS sufferers.
Sharon Forsythe, who was diagnosed with AGS in 2019, also hopes GalSafe products will be a game changer for AGS sufferers. “We sufferers live in constant fear of many medicines and medical products that contain animal components,” she reports in an interview. “Since I was forced to deal intensively with the matter, I know more and more people who have almost or actually died during operations or other treatments. What if I’m lying unconscious on the operating table, needing the blood thinner heparin, but the medical team doesn’t know I’m extremely allergic to it?”
A bite from the Ixodes ricinus, also known as the common wood beetle, starts the meat allergy.
Tick bite triggers allergy
Incidentally, a banal tick bite caused people to suffer. Because the allergy-triggering sugar molecule is found in the saliva of some species, including the Lone Star Tick, which is widespread in the southwest of the USA, or the tick species Ixodes ricinus, which is dominant in Europe. It is not yet entirely clear whether the ticks produce alpha-gal themselves or whether they ingest this sugar molecule with a blood meal on a mammal.
It is still not possible to explain why not all people bitten by ticks develop an allergy to alpha-gal, nor the fact that not everyone develops an allergy to pollen or peanuts.
According to studies, up to 30 percent of people in tick-heavy regions and people who work a lot outdoors, such as forest workers and hunters, are sensitized to alpha-gal, and an estimated five to ten percent of the general population. In the United States, the Lone Star Tick has been spreading westward for several years, and with it the AGS.
But sensitized does not mean sick. If someone is sensitized, it means that they have special alpha-gal antibodies in their blood, which in principle can trigger an allergy. But it is by no means the case for everyone. It is estimated that up to ten percent of those who are sensitized develop AGS.