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Some people develop allergic reactions to alpha-gal after they’re bitten by lone star ticks.
Alpha-gal syndrome is an emerging condition caused by the bites of certain ticks. The bites spur allergic reactions to a sugar molecule called galactose-α-1,3-galactose, or alpha-gal, found in red meat and other animal products. The sugar is added on to other molecules by many mammals. But humans don’t make alpha-gal, so the immune system may see those molecules as allergens.
Alpha-gal syndrome has been increasing in the U.S. and globally. About 110,000 suspected cases have been identified in the U.S. since 2010. The true number is likely higher, as cases often aren’t identified. Symptoms vary from gastrointestinal problems to life-threatening anaphylaxis. There is currently no specific treatment or prevention for it other than avoiding tick bites, red meat, and related animal products.
Monoclonal antibodies, which are lab-created immune system proteins, hold promise as treatments for specific allergies. They can potentially be used to block other antibodies like IgE from binding to allergens such as specific proteins in pollen, peanuts, and cats.
A research team led by NIH’s Dr. Peter Crompton and Dr. Scott Commins at the University of North Carolina at Chapel Hill set out to identify the benefits of monoclonal antibodies that target alpha-gal. The study was published in the Journal of Clinical Investigation on Sept. 1, 2026.
The scientists first made 42 monoclonal antibodies specific to alpha-gal from people exposed to malaria. They hoped to target alpha-gal in malaria parasites as a potential way to prevent malaria infection. When the antibodies didn’t bind well to the malaria parasite, the team screened the antibodies to see if they might be used to combat alpha-gal syndrome instead.
They found that 13 of the antibodies bound to allergens linked to the condition. Among these, two blocked IgE from patients with alpha-gal syndrome from attaching to certain alpha-gal syndrome allergens. One of the antibodies interfered with the activation of basophils, which are immune cells involved in allergic reactions.
Future studies will be needed to evaluate whether such antibodies could be used to prevent allergic reactions in people with alpha-gal syndrome.
“We are thrilled that this research is helping to advance the development of alpha-gal-specific monoclonal antibodies as a potential intervention for alpha-gal syndrome,” Crompton says. “This discovery is also a remarkable example of how collaborative global health research can lead to breakthroughs that improve the health and well-being of Americans.”
He added that a similar strategy might be used to make additional monoclonal antibodies that work against a wider range of alpha-gal allergens.