Haemaphysalis longicornis tick bites are a possible cause of red meat allergy in Japan

Recent studies revealed that Amblyomma or Ixodes tick bites may cause red meat allergy, in which galactose-alpha-1,3-galactose (alpha-Gal) is a major IgE-binding epitope. The incidence of red meat allergy is high in Shimane Prefecture, as is tick-transmitted Japanese spotted fever. Therefore, we speculated that tick bites may cause these meat allergies. The carbohydrate alpha-Gal was detected in the salivary gland protein of Haemaphysalis longicornis (H. longicornis), the vector for Japanese spotted fever, by immunoblotting using anti-alpha-Gal antibody. H. longicornis salivary gland protein-specific IgE was detected in the sera of 24 of 30 patients with red meat allergies. Sensitization to tick salivary gland protein containing alpha-Gal is possibly a major etiology of red meat allergy; the carbohydrate plays a crucial role in its allergenicity. These results further indicate that the alpha-Gal epitope is present not only in Amblyomma or Ixodes, but also in Haemaphysalis.