Anti-alpha-galactosyl immunoglobulin A antibodies (Anti-α-Gal IgA)

Anti-alpha-galactosyl immunoglobulin A (anti-α-Gal IgA) antibodies are naturally occurring human antibodies that specifically target the carbohydrate epitope galactose-alpha-1,3-galactose (α-Gal). This glycan is found on the cell surfaces of most mammals but is absent in humans and higher primates, leading to the production of these antibodies in response to environmental exposure, particularly from gut microbiota (NIH, 2022). Anti-α-Gal IgA is a major component of the secretory immune system, found in saliva, milk, and colostrum, where it serves a protective role by preventing the adherence of α-Gal-expressing pathogens to mucosal surfaces (PubMed, 1991). These antibodies are clinically significant as part of the broader immune response in Alpha-gal syndrome (AGS), a tick-bite-associated allergy to red meat and mammalian-derived products (CDC, 2024). They also contribute to the immunological barriers in xenotransplantation and can mediate adverse reactions to drugs containing the α-Gal epitope, such as the oncology treatment cetuximab (NIH, 2023). Therapeutic strategies involving these antibodies include their removal via immunoadsorption or neutralization using synthetic α-Gal conjugates like GAS914 to prevent adverse immune reactions (Frontiers in Immunology, 2020). Understanding the levels and specificity of anti-α-Gal IgA is important for managing allergic risks and developing strategies for successful cross-species organ transplantation.

Other names

Anti-Gal IgAAnti-alpha-gal IgAAnti-alpha-1,3-galactosyl IgANatural anti-Gal IgA

Binding to the galactose-alpha-1,3-galactose (α-Gal) carbohydrate epitope; neutralization of α-Gal-expressing pathogens; mediation of hypersensitivity reactions; target for immunoadsorption removal.