Alpha-galactose allergy
Alpha-galactose allergy (also known as alpha-gal allergy, alpha-gal syndrome, or mammalian meat allergy (MMA)) is a reaction to the carbohydrate galactose-alpha-1,3-galactose (alpha-gal).[1][2] In alpha-galactose allergy, the body experiences a sharp increase in immunoglobulin E (IgE) upon contact with the meat-derived carbohydrate.[3]
The alpha-gal molecule is found in all mammals except apes, humans, and Old World monkeys.[4] Since humans do not naturally produce this carbohydrate, humans do not have an pre-existing immune tolerance to the carbohydrate. The allergy most often begins when a Lone Star tick bite transmits alpha-gal into the body. In some people, an immune system reaction may later produce mild to severe allergic reactions when red meat is eaten.[5]
The cancer drug cetuximab (trade name Erbitux) contains the alpha-gal carbohydrate, since it is manufactured from mice. Cetuximab can cause a reaction in people who live in regions with a high population of Lone Star ticks, suggesting a link between Lone Star tick bites and an increased vulnerability to alpha-gal syndrome.[5]
Treatment[edit | edit source]
There is no treatment, other than not eating red meat.[5]
Symptoms[edit | edit source]
- Hives, itching, or itchy, scaly skin (eczema)
- Swelling of the lips, face, tongue and throat, or other body parts
- Wheezing or shortness of breath
- A runny nose
- Abdominal pain, diarrhea, nausea or vomiting
- Sneezing
- Headaches
- Anaphylaxis, a severe, potentially deadly allergic reaction that restricts breathing[6]
See also[edit | edit source]
Learn more[edit | edit source]
- Meat Allergy by ACAAI.org
- Jan 18, 2019 Mammalian meat allergy: How tick bites can cause allergic reactions to meat, milk and gelatine ABC AU
- Feb 24, 2019 Likelihood of tick bite to cause red-meat allergy could be higher than previously thought Science Daily
- Dec 6, 2019 Lone star tick a growing threat to humans, pets as populations expand in CT WFSB News
References[edit | edit source]
- ↑ Hilger, Christiane; Fischer, Jörg; Wölbing, Florian; Biedermann, Tilo (2019). "Role and Mechanism of Galactose-Alpha-1,3-Galactose in the Elicitation of Delayed Anaphylactic Reactions to Red Meat". Current Allergy and Asthma Reports. 19 (1). doi:10.1007/s11882-019-0835-9. ISSN 1529-7322. PMC 6344609. PMID 30673913.
- ↑ "The Oligosaccharide Galactose-α-1,3-Galactose and the α-Gal Syndrome: Insights from an Epitope that is Causal in Immunoglobulin E-Mediated Immediate and Delayed Anaphylaxis". European Medical Journal. July 17, 2018. Retrieved December 9, 2019.
- ↑ Commins, Scott P.; Platts-Mills, Thomas A.E. (February 2013). "Delayed Anaphylaxis to Red Meat in Patients with IgE Specific for Galactose alpha-1,3-Galactose (alpha-gal)". Current allergy and asthma reports. 13 (1): 72–77. doi:10.1007/s11882-012-0315-y. ISSN 1529-7322. PMC 3545071. PMID 23054628.
- ↑ Galili, Uri (September 1, 1993). "Evolution and pathophysiology of the human natural anti-α-galactosyl IgG (anti-Gal) antibody". Springer Seminars in Immunopathology. 15 (2): 155–171. doi:10.1007/BF00201098. ISSN 1432-2196.
- ↑ 5.0 5.1 5.2 "Alpha-gal syndrome - Symptoms and causes". Mayo Clinic. Retrieved October 27, 2019.
- ↑ "Omalizumab". Reactions Weekly. 1740 (1): 254–254. February 2019. doi:10.1007/s40278-019-58147-3. ISSN 0114-9954.
