Recombinant allergens: biological, immunological and practical aspects.

Molecular and biochemical characterization of atopic allergens has made considerable progress since the application of cDNA cloning techniques. A number of mite allergens, a hornet venom allergen (Dol V), tree pollen allergens, grass pollen allergens and allergens from ragweed were cDNA cloned and sequenced. For the mite allergens Der p I and Der f I, a thiol protease activity can be assumed on the basis of sequence similarities with plant thiol proteases. The major birch pollen allergen, Bet v I, is highly homologous to a group of plant pathogenesis related proteins, suggesting a similar function of the pollen allergen for the birch tree. Finally, the minor birch pollen allergen, Bet v II was shown by sequence comparison and biochemical properties to represent the actin-binding protein profilin, a protein found in all eukaryotic cells.