A novel inhalation allergen present in the working environment of beekeepers.

BACKGROUND Inhalation allergies, caused by allergens from various kinds of pollen, house dust mites, animal epithelium, and mould fungi, are strongly increasing in frequency. In 2.6% of the cases the allergen source remains unidentified. The present paper describes a so far unknown inhalation allergy which was observed in the case of a patient working with hives. METHODS AND RESULTS The allergen was characterized by immunoblotting, enzyme-linked immunosorbent assay inhibition, and isoelectrofocusing, using the serum of the patient. It is present in both the bee bodies and the larvae, has a molecular mass of 13 kDa, and an isoelectric point of 5.85. It is thermolabile and does not cross-react with allergens from birch, mugwort and timothy grass pollen, mould fungi, or bee venom. The N-terminal amino acid sequence of allergen from larvae was determined to be (2)QIEELKTRLHT(12). A similar allergen of 13 kDa was also found in Varroa mite accompanying bee populations. CONCLUSION Honey bees (including the larva stadium) and Varroa mite contain a 13-kDa protein causing an allergic reaction. Presently, there is no evidence whether the case described is a singular phenomenon or whether this allergen is a more common inducer of allergies among subjects exposed to honey bees. However, a bee and Varroa mite allergy has to be considered for beekeepers after exclusion of known inhalation allergies.