NIH finds antibodies blocking alpha-gal allergen binding in lab

A tick bite can turn a familiar food into a medical hazard. Alpha-gal syndrome, or AGS, can cause reactions to alpha-gal, a molecule found in red meat and other products from mammals; symptoms range from gastrointestinal problems to life-threatening anaphylaxis. NIH researchers have now identified rare antibodies that acted as a biological shield in laboratory tests, blocking allergic antibodies from binding to alpha-gal allergens.

The candidates emerged from an unexpected detour. Researchers at the National Institute of Allergy and Infectious Diseases initially isolated 42 antibodies targeting alpha-gal from people exposed to malaria, hoping to study protection against the parasite. Those antibodies did not bind well to malaria, but a follow-up screen found that 13 could bind allergens associated with AGS.

Two of the antibodies blocked IgE—the antibody involved in triggering many allergic reactions—from attaching to certain AGS allergens. A third interfered with the activation of basophils, immune cells involved in allergic responses. The experiments were conducted in the laboratory, not in people.

The need is growing. NIH says tick-associated AGS cases are increasing in the United States and globally, while approximately 110,000 suspected U.S. cases have been identified since 2010. Because cases are often not recognized, the actual number is likely higher. For now, avoiding red meat remains the only specific treatment or prevention described by NIH.

And so, concretely? The discovery gives researchers defined antibody candidates to test in future studies aimed at preventing allergic reactions or developing a targeted therapy for people with AGS. It does not yet change what patients can eat or offer a proven medicine: the results, published in the Journal of Clinical Investigation, are an early laboratory step toward that goal.