Galactose-alpha-1,3-galactose

Galactose-alpha-1,3-galactose, commonly known as alpha gal, is a carbohydrate found in most organisms' cell membranes. It is not found in primates, including humans, whose immune systems recognize it as a foreign body and produce xenoreactive immunoglobulin M antibodies, leading to organ rejection after transplantation. It has also been suggested to play a role in an IgE-specific allergic response to some meats. Recent studies are showing increasing evidence that this allergy may be induced by the bite of the lone star tick (Amblyomma americanum) in North America and the castor bean tick (Ixodes ricincus) in Sweden.